Category — Backmount

Endlich war es soweit, meine erster Kurs mit Landsmaennern und Frauen und dann auch noch eine super Gruppe von der Tauchschule Traunsee. Veronika, Andreas, Ursula und Markus kamen den langen Weg vom kalten Österreich hierher in die Riviera Maya um ihre bereits breite Erfahrung im Tauchen um eine Nische zu erweitern, Hoehlentauchen!!!

Von Anfang an war die positive Motivation und eine entspannte Atmosphäre zu spuehren, die natürlich den anstrengenden Kurs um einiges leichter machte. Die 4 wurden von Andy, einem Australier komplettiert. Da aber nur 3 Schueler pro Tauchlehrer erlaubt sind, teilten sich Nando und ich die Gruppe. Die Theorie erarbeiteten wir  immer gemeinsam und dann im Wasser trainierten Veronika, Ursula und Andy mit Nando; Markus und Andreas mit mir.

Die ersten Tage sind immer die längsten, bis man alles ins Rollen gebracht hat und so begannen wir täglich um 08:30 und unsere Tage endeten mit wenigen Ausnahmen gegen 18:00.Uhr..sorry =)

Tag eins begann mit Papierkram und sich ein bisschen kennen lernen, Hauptregeln und Ablauf des Kurses besprechen und eine kleine Vorschau auf das, was so auf einen zukommt…letzte Chance es sich noch einmal anders zu überlegen!

Nach ein wenig Theorie und einem ausführlichen Ausruestungs Workshop ging es ab zur ersten Cenote, Chikin Ha/Xtabay, wo wir uns um die Hauptfundamente kümmerten, und  zwar Tarierung, Trim und die verschiedenen Flossenschlagtechniken und all das in der neuen Konfiguration mit den Doppelflaschen.
Das Hoehlentauchen ist nicht nur eine körperliche sondern vor allem eine mentale Herausforderung, weil man sich zu jedem Zeitpunkt auf sehr viele Dinge konzentrieren muss, dabei sollte man eine stabile Position unter Wasser haben, ohne sich dazu großartig zu bemühen oder sich bewegen zu müssen.

Am naechsten Tag ging es gleich in der Frueh auf zur Cenote Cristalino. Dort angekommen verbrachten wir erst mal ein paar Stunden zwischen den Baeumen, um Uebungen mit den Leinen zu machen, damit man lernt, die Hoehle in Nullsicht sicher gemeinsam mit seinem Team zu verlassen. Dies war der Beginn vieler Uebungen mit geschlossenen Augen und die Antwort auf die Frage: Wie kann ich mich mit meinen Partnern verstaendigen ohne sie zu hoehren oder zu sehen?
Der gesamte Nachmittag wurde im Wasser verbracht, um das am Land Gelernte unter Wasser zu trainieren. Anfangs noch jeder fuer sich, dann  im Team. Jede Menge Situationen, wie sich im Seil verhaengen, keine Luft mehr haben, Tarierungsprobleme, Fuehrungsleine verlieren und noch viele andere mussten bewaeltigt werden. Und als ob das alles noch nicht genug gewesen wäre, hatten wir dann abends noch eine Lektion in der Theorie.

Am naechsten Tag war es endlich soweit, die ersten Hoehlentauchgaenge standen am Plan. Der erste noch mit dem Instruktor als Fuehrer, der naechste schon alleine als Team, wobei der Tauchlehrer nur alles aus der Dunkelheit ueberwacht und die Uebungen koordiniert. Die Cenote Ponderosa bietet sich hierfuer perfekt an, da es mehrere Leinen zu betauchen gibt. So machten wir 3 Tauchgaenge und begannen bereits mit Nullsichtuebungen, die schon gut gemeistert wurden, dank des ganzen Trainings vom Vortag.
Am spaeten Nachmittag als wir zurueck in Pro Tec waren, machten wir noch ein wenig Theorie und den Plan fuer den naechsten Tag.

Tag vier verbrachten wir in der Cenote Taj Maha mit Konzentration auf die Notfall Situationen mit mehrfachen ohne Luft Notfällen, Nullsicht Situationen und beides gemeinsam durch enge Passagen, die das Team zu mehrfachem Wechsel der Seite auf der Leine zwang. Es ging auch immer weiter in die Hoehle hinein.

Tag fuenf, brachte den Abschluss des Intro to cave Kurses mit den beiden Uebungen: Lost Line und Lost Diver. Zuerst verbrachten wir den Vormittag wieder damit, alles im Trockenen zu ueben um uns mental auf die Uebungen vorzubereiten und alles einmal vorher Schritt fuer Schritt duchzugehen.
Im Wasser haben wir die Uebungen dann auch noch mit „null Sicht“ und „ohne Luft“- Situationen kombiniert um das Training zu intensivieren.
Die Cenote Chac Mool bietet sich hierfür sehr gut an, da der Tunnel sehr dunkel ist und die Halocline das ganze noch um einiges erschwert. 

Endlich im „full cave“ Teil angekommen, ging es zurueck nach Taj Maha, um an den Verengungen zu trainieren und mit Sprüngen auf andere Leinen zu beginnen. Wir starteten, wie fast immer mit Leinenuebungen am Parkplatz und dann gings ab zum ersten 90 min Tauchgang wo eine Uebung die naechste abwechselte und wir uns zum Schluss waehrend einer „ohne Luft Situation“ bei null Sicht durch eine Verengung zwaengen mussten.
Alles lief super gut ab und die beiden tauchten mit einem breiten Lächeln auf!

Tag sieben verbrachten wir in der Cenote Minotauro um einen komplexen Circuit zu planen, vorzubreiten und durchzufuehren und noch mehr die Engstellen zu trainieren. Ein 106 min Tauchgang und ein 78 min Tauchgang waren dazu noetig…was fuer ein Tag und die beiden haben auch eindeutig ihre Lieblingshoehle gefunden.

Am letzten Tag ging es dann nach Tulum, in der Grand Cenote machten wir die letzten zwei Tauchgaenge ohne Uebungen um das Erlernte auszuprobieren. Zwei traumhafte Tauchgaenge durch dieses so wundervoll dekorierte System. Der perfekte Abschluss fuer einen tollen Kurs.

Zurueck in der Tauchbasis haben wir dann noch die Examen gemacht, die alle mit fast 100% bestanden haben und somit war es vollbracht, wir haben vier neue, oesterreichische Hoehlentaucher, und ich koennte nicht stolzer sein.
Ein herzliches Danke an die vier, die sich so tapfer geschlagen haben, auch wenn die Tage lang, die Woche noch laenger und die Uebungen hart waren… oesterreichisches Blut ist eben koa Nudelsuppen.

Ich hoffe euch bald wieder hier zu sehen, um euch ein paar der traumhaften Hoehlen der Riviera Maya zu zeigen…

Sonnige Gruesse aus Playa,
Patrick

The last weeks have been awesome, it started of with a basic Sidemount course, followed by a CCR experience, a multistage course, then Basic Cave DPV, an Intro to Cave course, taking some pictures with Matt and some guided CCR cave diving…I really like to do different things, so a schedule like this is just perfect for me.

First on the list was Tristan who lives and works here in Playa and felt it was time to expand his horizon and move into sidemount diving. First step was to work on a rig and after listing up his different options he decided to go with a basic webbing harness and a modified recreational bcd on top as buoyancy device. We used to first day for theory, talking about equipment, gas management, some history, benefits and dangers of sidemount diving among other things. The afternoon was spend with configuration and some time in the pool to fine tune the rig.

On the next day we went to Cenote Xtabay, to work on buoyancy, trim, fining techniques, equipment familiarity and zero visibility procedures. A very long day with hours in the water but leaving with a streamlined rig that started to be more and more an extension of Tristan’s body.
On the last day we went to Cenote Chac Mool to dive in low ceiling cave to show how easy and fast you can move in a sidemount configuration in passages that would really slow you down diving in backmount.

The very next day, I spent with Arthur who had just finished his cave course with Nando but wanted to try out CCR diving before going back to Poland. For his try out he chose the Classic Kiss . We met in the morning and I started with some basics on ccrs, different types and units, potential hazards and advantages over OC diving. Later we went to Ponderosa where he had the chance after some basic exercises to swim the unit in the open water and make his first bubble free experience underwater.

Right after that the finish invasion started with Lauri who came in from cold Helsinki to further his knowledge and experience in cave diving with a stage multistage course followed by a basic cave dpv course. A really perfect combination since it follows the principal of progressive penetration.
There are many different schools of thought coming from different point of views, environments, agencies and other ideas and so the first step always has to be to analyze and review them and see which one fits best ones believes. These also may change with time and from one environment to the next and so to be open minded and willing to try different things is the key in my opinion.
The main  topics for the two courses definitely should be different rules of gas management, streamlining of gear, team protocols, zero visibility training including pick up and switching, different failures and the response to these failures and then just train, train, train.
We definitely had a cool time and did some super nice long dives where one drill followed the next keeping us busy and alert. Lauri handled everything I was throwing at him from out of gas drills to zero viz having to pick up and switch to stages with his eyes closed while staying in contact with the team retrieving his scooter while lights out then towing and pushing fellow divers with dpv malfunctions and  all of that several thousand feet back in a cave. He mastered the techniques  necessary for long penetrations understanding the risk of these dives and accepting to start slow and never making too big steps. Now it is up to him to stay sharp and to adapt the skills learned in the Mexican caves to  the cold mine diving he is doing back home.

A couple of days later the finish invasion continued with Veli, Mia, Saara and Miksu that all came to do their intro to cave training with Matt and I. Although we had to fight with sickness and cancel sightseeing trips we fought our way through and at the end all four left as certified intro to cave divers.   I also had the chance to take Miksu and Saara on some guided dives afterward where they finally had the chance to try the learned outside the course environment. We went to places like Nohoch and Dos Ojos which are famous for their beautiful decorations.

Having some days off in between Matt and me took the opportunity to go and take some pictures  in Grand Cenote…here a little taste:

Finally I had the great pleasure to take Dr. Mel Clark on some guided ccr cave diving. Having been sick before I wasn´t quiet 100%  but to be around an energetic and fun person like her immediately made me feel better. She was packing her revo ccr and a camera and so we went for some longer dives taking what felt to me like 1000s of pictures. First day we were out at Cenote Pet Cemetery to dive both lines towards the blue abyss and a bit beyond. On the second dive we where joined by Michael another ccr diver with a Megalodon that made our team complete.
The day after we went to Mayan Blue to dive from B tunnel to E and F and finally back over towards A after the T. One of my absolute favorite dives!!!!
Definitely cool  to hang out with her and share experiences and discuss some different ideas, great time!

So that’s it, a short report on what I did the last weeks and maybe it also explains why I didn’t sit down in the evening to write about it, I was a bit exhausted =)

Thank you very much to all the divers that gave me the opportunity to show them a little bit of my world, it was a great to meet and dive with you. Hope to see you all back here soon!!!

Cheers
Patrick

When diving into caves, wrecks or under ice divers are introduced to a number of hazards not associated with open water diving. Some of these are easily managed. Others may be life threatening. General hazards include total darkness, loss of visibility, increased potential for confusion, unexpected currents, cave ins, restrictions, depths, unknown distances, mazes, turbidity / silting, current, sharp surfaces and projections, collapse, debris slides, restrictions minor and major, depth, distance, time.

Darkness

Absolutely no light penetrates most cave systems and one of the first things to realize is that the darkness is total. Not the slightest bit of light penetrates the solid rock ceiling, there are no stars and there is no moon. In caves the prospect of being lost in the dark can have chilling effects. When lost or when loosing ones light stress levels typically climb. Don’t let panic skyrocket. Cave diving requires disciplined self control to function correctly. This discipline must be learned and practiced.

Being Lost

Several common factors, or combinations of factors, contribute to the possibility of a cave diver becoming lost. Becoming lost is a threat on any cave dive. Caves frequently present divers with a number of mazes, dead ends and multiple levels of formation. Accidentally wandering into an unintended passageway can result in dive partners becoming lost. In fact, one of the leading causes of cave fatalities is the failure to follow a continuous guide line and set jump lines that lead all the way back to the surface. Guide lines are the diver’s path back to the entrance, they are a cave divers life line. Guide lines offer life insurance by providing cave divers with a marked path to the surface. It is imperative to keep an eye on these lines at all times. When visibility is good you should swim close to the line at all times so the line can be easily located. It is important not to stray too close to the line neither since the possibility of becoming entangled in it increases. Entanglements can become killers because they can result in broken or loosened lines. When limited visibility conditions occur, one must stay closer to the line. The best technique to stay in touch with the line once visibility has deteriorated is to swim with your thumb and forefinger forming a ring and looped over the line.

Visibility

In explored caves it is common to find permanent lines with arrows pointing toward the nearest route to the surface. Turbidity is caused by stirring up debris on the cave floor due to poor swimming techniques or due to percolation when exhaust bubbles hit the ceiling. It can reduce visibility to zero within seconds. From both a dive safety standpoint and an environmental point of view with cave conservation in mind, it is important for you not to stir up the bottom of a cave. Tannic acid is the color of soil and can be washed into the water by rivers or rain. It has the color of tea or coffee with the same visibility characteristics. A Halocline is the interface of fresh and salt water and when mixed produces zero visibility.

Water Flow

Current in caves can range from none to mild and even to severe. New cave divers are often intimidated by these currents. They tend to overwork and become tired quickly. By carefully employing proven techniques, the work may be reduced to a less demanding level. The best way to beat the current comes with learning to read the cave. Areas where the surface is smooth have been polished by the flowing water. So, you should look for jagged and pitted surfaces. They exist where the current is weakest. Current can also be out flowing or in flowing. Sometimes caves divers may encounter passageways featuring flows differing in direction from the passage currently being explored.

Cave or Wreck Collapse

Cave-ins ( collapses ) are rarely encountered in cave diving. Water pressure acts as a support and stabilizes submerged tunnels. It is only when water levels drop that the possibility of collapse exists. Occasionally, in some caves a small portion of the cave structure will fall in.

Debris

During floods, debris builds up in the down slopes of cave openings and in the runs. When the water table drops, additional debris is blown out of various passageways and is deposited on the cave floor. As these strictures extend toward the surface, more debris builds up in the run. At some point, the volume of these deposits reaches a point where gravity causes it to slide back into the cave. The result, in both cases, is an instantaneous loss of visibility. In fact, on one of these occasions visibility can be so obscured that it would proof impossible to get out if divers hadn’t had the mandatory foresight to install guide lines beginning at the cave opening. In some situations, it is possible that the cave opening actually becomes blocked.

Restrictions

Restrictions are choke points where access is reduced. They can be either minor or major. A minor restriction is a slight narrowing which, although restricted, still allows two divers to pass through it not side by side or on top of each other but in a single file following one another. A major restriction, on the other hand, only allows one diver to pass if the equipment is to be taken off and pushed through the restriction. As a rule of thumb the equipment is never taken off due to potential problems with buoyancy, damage, entanglement and cave conservation. If the need arises to pass through a mayor restriction gear configuration such as sidemount or no-mount have to be implemented. Obviously, the risk associated with a major restriction involves becoming stuck. When entering restricted areas be careful to evaluate the best passage route while also concentrating on relaxed breathing. If stuck, exhale some air and slowly maneuver your body and simply dislodge your self. Do not try to “ power through ” restrictions. You may become severely wedged. We can’t stress it hard enough. Take it very easy when swimming in tight spots. It is very easy to tear a BC bladder or damage your gear. Again, learn to read the cave and avoid abrasive and protruding surfaces.

Depth

Depth in caves can be very deceptive because you have a roof over your head and a floor under your feet. Don’t forget to monitor depth regularly. Depth increases gas consumption, the risk of nitrogen narcosis arises, can cause oxygen toxicity and produces a greater decompression obligation. This is why many cave divers use Normoxic or Hypoxic Trimix mixtures for deep cave exploration.

Distance

When a problem arises we realize it’s a long way back. Distance, in this instance, may produce additional time-pressure stress. In worst case scenarios, your gas supply may be compromised if one team member experiences gas failure. Training and awareness, combined with careful planning, will enable you to deal with the hazard of distance. The ceiling over your head prevents direct access to the surface. This is why highly reliable equipment combined with redundancy is used for cave diving.

Changes in respiratory patterns, such as response to mental and physical stress will also increase gas consumption. When divers slow their pace, gas consumption is reduced. Never forget that your exit speed must match your entrance pace. You must cover the same amount of ground in the same time “coming out” as “going in” to insure you won’t run out of gas.

Air and Team Management

Since dive teams are obviously composed of individuals, a “ team gas management ” rule must be established. This rule incorporates all the factors involving individual considerations with another dimension. This dimension is created by people working together. When diving alone, dive techniques and gas management are different as if diving as a team member of a dive team.

The size of the dive team will dictate effective gas management. Obviously a two person dive team is the most efficient from a dive performance standpoint. It needs less communication and requires less choreography. Both divers know where their partner is. Swim pace is easier to regulate. A small team reduces the level of environmental management needed. For example, silting is just one of many factors that’s easier to anticipate and prevent.

However, there are strong arguments to support the advantages of a three person dive team. The group gas supply can go much further when shared between three people. Two people are usually better able to rescue an individual in trouble. Irregardless, the gas plan to be used must be developed from a swimming based surface rate ( vs. a resting rate ). It must be fine tuned by adjusting anticipated gas consumption against the environmental factors you expect to encounter. Experience has taught us this method is almost always totally accurate for planning dives involving a lot of swimming. To do this right, all dive team members must know their individual RMV’s.

Even with proper gas matching, it is still imperative that all dives remain within normal parameters for these rules to work. When conducting cave diving on your own, or with new team members, it is advisable to add a couple of hundred psig / dozen bars to any turn around point and turn around earlier. This practice should be continued until divers have sufficient experience to develop the discipline to function normally under stress.

Running out of Air

By taking corrective actions with gas supply problems, for example, before things escalate, divers can begin sharing gas before the diver with the problem actually runs out completely. This is good stress management. It allows the distressed diver to use his or her own gas whenever a restricted or hazardous point in the dive is reached and share air in the long, unobstructed passages. Once any member of the dive team is using a back up regulator, the dive should be terminated. All divers should begin their pre-planned exits.

I recently had the great pleasure to hang out and dive with two fellow dive professionals from the other part of the world:

Tom from the Philippines and Kelvin from Truk Lagoon. Both of them came by after they had visited the DEMA trade show. Tom just the day before Hurricane Ida and Kelvin just after. At first we were a bit nervous if Ida would destroy our plans of cave diving the next days but then she passed us far and we only got a day of wind and rain followed by excellent weather.

Tom was in for some guided cave diving to see what the Mexican caves were all about and so we sent him out with one of our guides to give him an overview. Unfortunately he was on a tight schedule planning to do other things besides cave sightseeing and so Santi could only show him the tiny little tip of the iceberg leaving a lot of fantastic sights out of the tour.
On the plus side Tom could use the time to get certified as Basic Sidemount Diver which was a new experience for the PADI Course Director who also happens to be Instructor for Cave and CCR diving.
It is one of the greatest things for me about this sport that even after years of working in this industry and having logged thousands of dives there are always things left to do and new techniques to be learned. It simply never stops, always fields and places left to explore.

It was definitely cool to share stories and experiences with him as well as comparing techniques and protocols. I definitely took a lot from it and am always grateful to encounter open minded people who like to share their experiences and knowledge with others.
I hope to see him back here soon for some more…this time Sidemount cave diving. Or maybe Wreck diving in the Philippines.

Kelvin is running a big technical diving shop in Truck Lagoon which is one of my dream destination since my wreck diving days in Egypt. Just the drives in the car to the Cenotes were super interesting and filled with stories about sunken battle ships and wreck diving techniques in comparison with cave diving techniques. We also have both a passion for mixed gas deep diving, which made for interesting discussions about decompression theory, gas selection and ascent protocols.

Kelvin was thinking since a long time to come to Mexico and start with cave diving but it had never quiet worked out until now. He started his course with Santi who dialed him in on buoyancy, trim and propulsion, as well as giving him his first experiences in the non metal overhead environment. All in all a good start and preparation to the adventures that were yet to come.

Once I came back from Toluca we met in the evening and the next day we were diving the three of us together. Objective of the day was to finish Toms Sidemount course and for Kelvin some more time to get used to fresh water and train the skills he had worked on with Santi.
The next day it was me and Kelvin in Chac Mool working on lost line and lost diver drills. A nice day with lots of discussions about procedures and protocols and eventful dives with multiple emergency drills. We train hard and dive easy!

The next couple of days we were getting into restrictions and navigation and even though we had to fight with equalizing problems on Kelvins part we still managed to finish the course. Kelvin had a great time and did not only learn some new diving skills but also learned some things about himself. Often asked questions about how he would react in certain situations where answered during the course.
I hope to see him back here soon as we did not have any time after the course to go and do some fun diving. There are still sooooooooooo many caves he has to go and look at! I am also looking fwd to meet his wife as she was the star of most of Kelvins stories…although I have to admit I am a bit scared =)

Looking back it was just one of these times where you get the chance to hang out with some good people and share experiences, stories and a lot of laughter . Although we are all from different parts of the world, have a different age and different opinions about a lot of things, we are all still united by the same passion and fascination of the aquatic realm.

Now I stop writing and go diving instead!

Cheers
Patrick

This project has been long time in the making. October 2008 was the first time Leszek and his guys where diving with me, only a couple of days to get back into Mexican cave diving. In February 2009 the team was back with a bunch of brand new Cuda dpvs and ready to scout dos ojos to see how the lines had changed since there last project in 2005. It was also used to train their side mount techniques utilizing multiple scooters and stages.
Now in October 2009 almost exactly 4 years later they had assembled a strong 7 man team to try and push their old distance. The first days where used for scouting as well as establishing procedures and protocols for the team. Leszek also tried different equipment configurations to determine which would work the easiest for his 10h run time. He went from back mount to side mount and even tried a “quad” (4 tanks on the back) but ended up deciding that side mount with additional stages would be the best compromise given that he was diving solo and the passage seize especially downstream of cenote monolito.

In the same time other team members where locating and cutting trails to different cenotes which would be used as possible bail out points. The day after the whole team including 4 Sherpa where taking off to cenote kentucky castle 1.3km in the dense jungle to scout the lines around this area as well as leaving some equipment staged for the big dive.

The day after we decided to take a brake and relax a little, which also gave me the time to prepare some   custom gas blends for the deep dives that followed in the Pit. These deep dives where the last missing puzzle pieces for the declared long distance dive that would start off with a deep drop at the short line right under the cenote.

Everyday passed in a very relaxed atmosphere with plenty of laughter and good spirits. Always with a cooler full of drinks and food and hammocks for the surface support to relax while waiting for the dive teams.

Finally the day had arrived and we started our day early at Cenote The Pit. In the days before we had finished dropping tanks, scooters and lights at predetermined locations through out the cave which would enable Leszek to travel the 17km without ever having to surface.
He started his journey with a drop to 72m before exchanging tanks in the dome and then taking off towards the passage named link. After reaching the end of the line there, he turned around and passed the pit once more on his way to tikin chi and afterwards to Cenote Kentucky Castle. There a team was positioned which informed the rest of us when Leszek was passing by. Then he made his way towards Cenotes M1 and M2 but was forced to turn as a collapse had made the passage too small for him to pass. Now he was on his way downstream and followed the lines up to the end of the LSD area and back. He was making good speed, reaching every waypoint at almost the exact previewed runtime. Half way through he passed the Main Entrance of Dos Ojos and now continued downwards to Cenote Monolito passing several other Cenotes on the way. There he changed his gear to slim down for the restrictions lying ahead. After almost reaching Cenote Hilario he truned back and finally surfaced slightly tired but happy in Cenote Esteban where the team greeted him and took his gear for the final 500m walk back to the cars. It was almost 10 o’clock at night and his Liquivision X1 marked exactly 558min after submerging.

A great achievement and the perfect end for an awesome project that lasted at the end for 12 days. I really had a nice time with genuine people that always smile and joke even after a 90min hike through the jungle with a 30kg backpack and 1.2million mosquitoes chasing them.

The team:
Leszek – dive leader
Remek – main support diver
Cisek – rescue expert and support diver
Mirek – support diver
Bogush – surface support and protection =)
Richard – surface support and equipment expert
Waldek – surface support and equipment expert
Patrick – logistics, transport and diving safety officer
Lucio – Equipment transport at Pit

This will definitely not be the last you heard from this extraordinary team as future projects are already planned.

Stage cylinders are generally used in addition to “back mount” cylinders or in addition to “side mount” cylinders while cave diving.  The reasons that cave divers, wreck divers and technical divers use stage cylinders include but is not limited to increase the total volume of gas during a dive so that penetration distances or dive times can be greater, to hold different gas mixes (for example a decompression mix, a travel gas, or a bottom mix), to hold a volume of gas needed for team planning or as a safety bottle, and to provide an open circuit bailout source during Rebreather diving applications, to provide safety air volumes needed when planning dives using DPV’s and calculating for failures requiring a swim out.  The diver throughout the entire dive may carry these cylinders, depending on the objective and dive plan, or they may as well be placed along a cave or anchor/ascent line to be retrieved during the exit from the dive depending on the environment and conditions they are diving. 

Diving with single and multiple stages in the overhead environment (cave, wreck, or decompression) should only be attempted by divers who have perfected diving skills in their back mount or side mount gear.  These advanced techniques are to be used only once a diver has achieved perfection in the environment they are diving and have a real need and desire to progress greater into the dive.  The reasons divers use stage diving techniques may be enticing but as well with these practices comes a greater responsibility and greater risks for divers to be aware of.  Divers are now entering further into the overhead environment, they may be leaving tanks in water filled caves which may impact the cave, and they are increasing task loading during the dive while making a more complex dive plans.  Divers using the techniques and information in this manual must as well understand and completely accept the risks involved in planning extended penetration dives.  

Stage bottles need to be secured to the divers harness via clips to the d-rings. The preferred clip is a bolt clip made out of stainless steel due to a longer life span and ease of use while brass clips become more difficult to operate with time. The size of the clips is depending of the environment, where cold water divers need larger clips due to the gloves or mittens worn. A carry strap can be attached to the stage bottle with the two clips firmly attached to the strap. The strap is used below water to handle the tank and less for the surface. A stainless steel clamp covered in a tubular webbing makes a perfect tank band to hold the strap in place. The connection from tank to clip should be of a cutable kind, a metal to metal connection is not desirable since it can not be cut in case of a clip failure or entanglement scenario when it becomes important to drop or remove the stage tank to solve the problem.

All stage tanks should be labeled clearly in regards to what breathing media is inside the tanks, the marking of maximum operational depth on the side of the tank in large number does have the advantage of the team members being able to see and verify that the correct breathing mixture is being used ant the correct depth.

Each stage regulator does need its own pressure gauge with a preferable short high pressure hose of about 15 cm length. The gauge is bend upward during use and attached to the first stage via a bungee cord or surgical tubing. During periods of non use the gauge can be released to ease the stress on the hose. During the dive when the stage bottle is not in use the valve is to be maintained close, during descent and at maximum depth the valve should be opened shortly to pressurize the first stage, a prevention of water entering the first stage due to pressure differences.

Safety and Deco

Decompression diving and accelerated decompression schedules are in need of a variety of breathing gases ranging from bottom gases to travel gases and a variety of decompression gases. All these breathing media have to be planned, blended, labeled, analyzed and then used at the appropriate time and depth during and according to the dive plan. Depending on the environment dived and the planned bottom times stage tank size and material are of consideration to the diver, while most divers prefer aluminum stages because of their lesser weight and lift requirements.

In ocean drift diving and wreck diving scenarios the decompression stage bottles are usually carried by and with the diver throughout the whole dive, even if that means that the breathing mixture is carried below safe breathing depth. In cave diving scenarios the decompression stage bottles are clipped to the line in a way that not to much stress is exerted onto the line and left at a depth where the breathing gas can be safely breathed, eliminating the potential danger of breathing the wrong mix at the wrong depth.

Extended Penetration

Stage diving must be well thought out. Staging allows the diver to extend the distance of safe exploration. Due to being further into the system it may also produce additional time pressure stress. Training and gradual build up in penetration distances will help offset this stress. In addition stage diving is similar to flying a airplane in that the diver must think well ahead of their position. By thinking ahead and being familiar with stage techniques the diver avoids delays during stage drops and retrievals and the diver will also avoid sudden changes in buoyancy.

Stage and multi-stage diving are other techniques used to further penetration into the caves or wrecks but allows as well longer bottom times during technical dives. When a diver reaches his turnaround pressure but wishes to further penetrate the cave or wreck then a stage or extra tank becomes a necessity. A stage tank can be worn on either side or all on the left hand side depending on configuration preferences. The dive is generally started on the stage tank and when the pre-established turn pressure is reached the diver switches over to another stage or the primary tanks either back mounted or sidemounted. When turn pressure on the primary tanks is reached the diver will turn around and will find his or her stage that was clipped to the line, then change over to the stage tank and exiting the cave or wreck breathing of the stage tank or tanks. Stage diving has a potential high impact on the cave and wreck environment and damage can be extended far into the cave or wreck. Care should be taken not to harm the cave or wreck. Special training is needed to use stage tanks safely in the cave or wreck environment.

Gas and Stage Switching Procedures

How you and your team will switch between your cylinders during the dive needs to be preplanned and practiced in open water situations prior to attempting them in the overhead environment or in real decompression situations.  There are a few common and ¨accepted¨ ways that this can be accomplished.  However your team decides to accomplish gas switches it needs to be remembered that there are many things that can go wrong when switching gases and going to and from regulators.  The end result of an improper switch can end in loss of gas, loss of a way to deliver gas, hypoxic and hyperoxic situations.  Gas switches no matter how done need to have the entire teams attention at 100%.  This is true if you are doing a switch to a bottom gas, travel gas, or a decompression gas.  In addition to verifying your own gas supply and system you must also verify that the other members of your team have made a proper switch as well.

Entire team switching gas and stages

One way that teams prefer to switch gases is the entire team switching at once.  This means that at one point, after the signal has been given and confirmed by the entire team, every member of the team will initiate and switch gases at the same time.  The sequence for this is:

a.     One team member gives signal to switch gases upon arrival at the correct depth or point of dive

b.     Team confirms the need and place to switch

c.      Every diver locates proper cylinder

d.     Divers read labels and check depth vs. MOD

e.     Everyone turns on the correct stage cylinder

f.       Divers deploy regulator of stage and get it into position to breathe

g.     Purge regulator you are planning to breathe from, confirm it will supply gas

h.     Switch to new regulator and breathe prior to storing previous gas (you may need to go back to it)

i.        Store hose that is no longer needed

j.       Trace regulator back from your mouth to the stage bottle and check mix and MOD vs. your actual depth

k.     Check other team members to verify they are doing switches and to proper tank and breathing gas

l.        Once all team members have switched and confirm okay, continue dive or decompression

This type of switch is best accomplished with all the team members facing each other.  While you are completing each of your steps you are as well going to be keeping up to date with what the rest of the team is doing.  How is their buoyancy, are they at the correct depth, are they switching to the correct tank, is the tank on, is somebody out of gas?  The ability for every member of the team to be able to see each other and the cylinder that each member switches to is critical.  A wrong switch to a wrong tank and breathing gas is a life-threatening event for every member of the team.  Every team member must stay in complete control of the procedures during this time of task loading. 

Individual Gas Switches

The second style of gas switching is very similar to the first in the stops but has a different team strategy.  Some teams prefer to switch with one person always acting as observer.  This means that one person will delay their switch and act as an observer until the rest of the team has confirmed their switch.  Upon confirmation of the gas switch of the rest of the team this diver will then switch gases with the rest of the team observing them.  This second way will take a longer time to get the entire team switched but gives you the added benefit of always having one diver less task loaded and paying attention to confirm the switch of the other team members and can respond in case of any failures.

a.     Team member gives signal to switch gases upon arrival at the correct depth or point of dive

b.     Rest of team confirms the need and place to switch

c.      Rest of team locates proper cylinder (leader does not switch)

d.     Team read labels and check depth vs. mod (leader observes)

e.     Team turns on the correct stage cylinder (leader observes)

f.       Team deploy regulator of stage and get it into position to breath (leader observes)

g.     Team purges planned next regulator, confirming it will supply gas (leader observes)

h.     Switch to new regulator and breath prior to storing previous gas (leader observes)

i.        Store hose that is no longer needed (leader observes)

j.       Team traces regulators back to the stage bottle and check mix and mod vs. actual depth (leader observes)

k.     Team members verify they are done with switch and to proper tank (leader confirms or makes any adjustments needed)

l.        Upon completion and confirmation of the entire teams successful switch the team leader will then start at the top of the list and complete theirs with the rest of the team acting as observers.

Once the team leader has switched and now the entire team is on the new breathing gas and or stage tank the dive will continue or the decompression will start.

Either way that you decide to switch gases team members must be responsible for their own switch while ensuring the safety of the other team members.  Regulators will be coming out of mouths making potential out of air situations more likely.  In situations of reduced and zero visibility extreme caution must be used, especially when you are carrying mixes that have maximum operating depths shallower than any parts of the dive.  A wrong switch has been the end of divers lives on more than one occasion, usually involving switches to high oxygen content tanks at depths over maximum operating depths.

Valves

North American valves have a safety feature called a burst disk. That disk, located behind the outlet is designed to release overpressure inside the tank in case of an fire of the tank being left in intense heat. That safety feature can be a potential problem with failing burst disk releasing all the breathing gas at once, specially if no isolator is used. Some diver plug the burst disk completely or use a higher burst pressure disk in order to avoid that potential problem. Other divers use valves made in Europe, where burst disks are unknown.

Knobs

Valves are the gateway from the high pressure gas inside the tank to the first stage and should be treated as a piece of life support equipment. While most valves come with soft rubber valve knobs some other materials are used such as hard plastic or even metal knobs. The advantage of the softer rubber knobs is that hey do not have the potential of shattering upon impact to a wreck wall or cave ceiling but absorb some of the shock and stay in place. Rubber knobs have a much better grip on almost any surface and with that the potential roll shut of a valve is much higher when diving in overhead environments such as caves or wrecks, and after each contact it is imperative to check the valve and make sure it remains in the fully open position. Metal knobs upon impact can bent and make it impossible to turn the valve and or break off the stem due to the inability to absorb some of the shock. Metal knobs and hard plastic knobs do not have as much grip and somewhat reduce the roll shut scenario but have the other above mentioned potential disadvantages.

K - Valve

The regular K-valve is the simple on – off valve with a single outlet to attach a single first stage to it. While these valves are simple and common around the world they do not offer the option of attaching a second first stage to it, and with it do not have the redundancy of dual outlet valves such as the Y or H-valve. K-valves are no suitable for cold water diving, cavern, cave or wreck diving applications.

H and Y - Valve

The H or Y-valve has two outlets to accommodate two first stages. On either first stage is a second stage attached and both valves are open at all times. If a free flow or complete regulator failure occurs the diver is in the position to self rescue him or herself in order to return safely to the surface. Cold water or ice diving with its potential for regulator freeze up, cavern or cave diving including wreck diving with overhead environments can not be dived without the use of a dual outlet valve for redundancy.

Manifold

The manifold was designed to access two tanks with one regulator two avoid the necessity of changing regulator regularly and the potential of a diver forgetting the change of regulator with the result of the diver having one tank empty and the other full, loosing all his or her redundancy in the breathing gas supply. The first manifold had only one outlet, allowing only one first stage to be attached, not allowing any redundancy in regulators and air supply.

In most double tank dual valve manifold systems, the left valve turns off in the direction of travel (counterclockwise) and in case the valve handle is bumped during the dive against the cave or wreck ceiling it is possible that the forward momentum could shut the gas supply off, leaving the regulator without gas supply. Every contact between any object and the tank valves must be investigated and the fully opened valve position must be assured.

The breathing gas delivery system features a dual outlet valve with two first stages and two second stages. One first stage has to have a 7 foot / 2 meter hose, attached to the right post. One SPG on the left post and one inflator hose on the right post are needed and are divided between the two first stages minimizing a situation both ( SPG and inflator ) are lost at the same time if that regulator had to be shut down. Common sense tells us in event of a emergency requiring a regulator shutdown the dive should be terminated. If the divers are adhering to the rule of thirds, there will be enough gas to return to the surface and an extra pressure gauge is not needed.

200 Bar and 300 Bar threads are in common use the 300 Bar thread is coming from a development in Europe where the trend and tendency is to smaller tanks with a higher pressure while in North America the trend and tendency is to larger, high volume and low pressure tanks which are often over filled. Many diver feel that the longer 300 Bar connection and thread is giving a better seat and connection, which is not necessary until the tanks are filled to 300 Bars.

Isolator or not

The isolator valve, located in the middle of the manifold enables the diver to isolate the two tanks in case of an catastrophic failure such as a burst disk failure or a tank neck / valve o-ring. In case of such an event the isolator valve is to be closed, the dive to be terminated and the diver is to breathe as long as possible form the leaking and depleting air supply, then change over to the isolated remaining tank and if the breathing gas supply is not sufficient ultimately starts sharing breathing gas via the long hose with one of his dive partners. If no isolator manifold is used the complete breathing gas supply will be lost and gas sharing has to be commenced at once, denying the diver self rescue capabilities.

The way an isolator valve can safe our life it can be a potential risk when closed in moment it should be open. During tank filling or breathing gas blending operations the isolator has to be open not to only half fill the double tanks but to avoid the creation of toxic breathing gases when filling oxygen and or helium into only one tank and the air for the blending process into the other. When the pressure is checked a full tank could be the result but breathing could be commenced of the wrong tank with the hypoxic or hyperoxic breathing mixture.

During or before a dive the isolator could be closed involuntarily or just be forgotten to be opened again during the pre-dive valve shut down drill. Such a closed isolator can lead, and had led to deadly accidents. If a diver closed his isolator he will breathe only from his or her right tank. The SPG is not connected to the right post tank but the left post regulator, and will not change its pressure during the dive. This is a very serious situation and the diver should realize that he has not an excellent day on air consumption, but has forgotten to open the isolator and is not using any gas from the left tank. On occasions where divers select to have the SPG connected to the same tank as the breathing regulator the tank pressure may fall to fast, not because the breathing rate is extremely bad this day but because the isolator is closed. Needless to say one must check his SPG often and take the right conclusions and actions from the information collected, and a confirmation of an completely open isolator before entering the water can avoid potential problems.

Regulators

While divers spend a great deal of money, time and commitment to get the best training possible it is amazing to see that there are a lot of dives out there who use inferior regulators and do not see the point of the regulator being life support equipment in a otherwise hostile environment. It is the regulators that deliver our breathing gas to us from our tanks and as we progress from recreational to advanced forms of diving with limited or no access to the surface, or changing diving environments from moderate to cold water diving we must reconsider our choice of regulators.

Regulators fall into a variety of categories ranging from a primary regulator that is our main regulator we are breathing from, to the secondary regulator or backup regulator that is hanging on a bungee around the divers neck, to the stage regulator used on stage tanks to extend cave penetration or extending bottom time to the decompression tank regulator who is used for nitrox mixtures or pure oxygen up to argon regulators used to feed argon from small tanks into our dry suits to enhance thermal comfort.

Each one of these regulators has his own specific requirements regarding balanced or unbalanced first stage or second stage, oxygen clean or not and second stages that can be adjusted or not. Downstream type regulators are preferred over upstream type regulators and all hoses should be interchangeable without any special hose or connector diameter. The use of 90 degree turn pieces is discouraged to prevent restriction in gas flow along with any type of adapter that is going in-between a hose connector and first or second stage.

In an extreme emergency one can breathe from the BCD while inflating the BCD with the power inflator and breathe the gas coming from the right post tank valve. A rare case of closing the left control knob while being in contact with a cave or wreck ceiling and then breaking the valve control know off would still enable us to have access to this last resort while accessing the right post valve and low pressure inflator hose including the ability to inflate the BCD while sharing gas with the long hose.

Balanced versus Non Balanced

First or second stages are either balanced or unbalanced. A balanced regulator is compensated for the environmental pressure and it takes the same effort to take a breath if the tank is either full or empty. Balanced first stages are a must for advanced forms of diving such as wreck, technical or cave diving with a choice of adding the breathing comfort of a balanced second stage. The extra performance and comfort comes with a price and more complexity in the design of balanced first or second stages. The balanced regulators provide ease of breathing with maximum performance while unbalanced regulators are less performing but of a more durable design.

Piston versus Diaphragm

Named after their internal design and working principle the first stages do either have a piston or a diaphragm that is in contact with the ambient pressure and water in order to regulate the intermediate pressure and gas flow to the second stage. Cold water divers prefer diaphragm first stages due to a higher resistance of regulator freeze up while other divers prefer the diaphragm first stage for the ease of gas delivery. While piston regulators have a tendency to freeze up easier in cold water conditions the manufacturers offer anti freeze kits to prevent that problem successfully.

Hoses

Hoses should be of the exact custom length for the individual diver with high quality materials used and providing maximum gas flow. The hoses must be checked regularly and replaced as soon as any wear or tear manifest itself.

The second stage hose of recreational divers is usually 32 ‘’ while many diver find that it is easier to share gas when the donating diver is using a 5-7 foot / 1.5-2 Meter hose instead of the 40‘’ regular octopus hose when using the Hogarthian configuration based on the long hose looping under the waist band or under the primary light if one is used.

If participating in more advanced forms of diving such as wreck, technical or cave diving a 7 foot / 2 Meter long hose is a must when the divers either have to swim or scooter any horizontal distance, are engaged in decompression diving or have to pass through small passages and being forced into single file. Any shorter hose then 7 feet / 2 meters will not allow the divers to facilitate an effective and proficient gas sharing, and exit while passing through restrictions.

The primary regulator has a clip attached with a break away connection, close to the end of the long hose right next to the second stage. If the long hose is not in use during decompression when using another regulator and breathing gas or during an out of gas situation and gas sharing operation the long hose is clipped of to the right chest d-ring to prevent entanglement, regulator and environmental damage.

When diving in double tanks the primary long hose regulator is coming of the right hand post enabling the user to get the full length of the hose out for singe file exits. Of that same right hand post is coming the inflator hose, crossing behind our head to the left and feeding the BCD inflator. The left hand post is accommodating the short hose backup regulator, crossing behind our head to the right and coming over our arm below our chin to be attached to a bungee cord necklace hanging around our neck. The same left hand post is accommodating the pressure gauge hose leading down to  our waist band d-ring.

The advantage of having the long hose on the right post beyond getting the full length out of it is the fact that the right post control knob is rolling open and if breaking off in the open position it will stay open with the long hose enabled. If the left post rolls shut and possibly breaks off when diving close to a ice, wreck or cave ceiling with the long hose is attached to it, the left post will stay close and the long hose will be lost to the team. Gas sharing scenarios where the out of air diver will most likely leading out, passing a restriction there is no way for the out of air diver to signal the donor behind him that he is out of air, and drowning will result.

DIN versus Yoke

There are two ways to connect a first stage the tank valve, one is the DIN ( Deutsche Industrie Norm ) and the second one is the Yoke or A clamp. The Yoke connector is used mainly by recreational divers due to ease of use but has the disadvantage that this connection often leaks gas and is not as streamlined as the DIN connector due to its large clamp surrounding the valve. The o-ring of the Yoke connection is located on the tank valve being subject to much more abuse then the DIN o-ring. The DIN connector is a very streamlined design and construction with the o-ring located inside the first stage stem connector and when assembled is embedded inside the valve for maximum o-ring sealing and protection.

Pressure Gauge

Following the concept of streamlining, keeping it clean, gear and environmental protection the best place for the pressure gauge is for the hose to come down from the left post, having the exact length to connect and be clipped into the left waist d-ring. This configuration provides the cleanest and most protective approach. Some divers prefer to have the pressure gauge coming under the arm and clipping it into the left or right shoulder d-ring to facilitate the reading of the gauge specially with a lot of additional gear and stage tanks. The use of two pressure gauges is over-redundancy and not needed since we will abort the dive inside turn around pressures including reserve volumes. All a second pressure gauge does is creating more failure points in our life support system. Any boot or console increases drag and a greater chance of environmental impact or entanglement.

Часто ученики спрашивают меня, что они могут сделать, чтобы лучше подготовиться для курса и ответ, конечно же, есть. Для большинства, кейв дайвинг вначале это - невероятная работа, связанная с борьбой с основными навыками.
В настоящее время термин «основные навыки» звучит как что-то простое и легкое, что на самом деле не является правдой. 
Когда я говорю «основные навыки» я, как правило, подразумеваю следующие три вещи:

1) Плавучесть
2) Положение в воде
3) Техника движения

В любительском дайвинге мы привыкаем ко многим вещам, которые зачастую приводят к обратным результатам в кейв дайвинге, и поэтому для опытных дайверов прохождение курса иногда оказывается труднее. Во-первых, они уже имеют определенные «плохие» привычки, с точки зрения кейв дайвинга. И, во-вторых, они легче получают разочарование, когда что-то не получается. Зачастую, они более требовательны к себе как к инструктору и в состоянии недовольства их эффективность снижается, что является так называемым порочным кругом.

Итак, давайте посмотрим, что можно сделать, чтобы получить преимущество и как можно больше удовольствия в первую пару дней курса.

Плавучесть:

Обычно в любительских погружениях мы привыкли погружаться на дно, добавляя нужное количество воздуха в жилет до нейтрального уровня, и затем используя наши легкие для конечной правки плавучести. Во время погружения, когда я водил группы в Красном море, как правило, менее опытные дайверы использовали инфлятор намного чаще. В кейв дайвинге это практически противоположно. Пещера диктует нам контуры и профиль погружения и зачастую, здесь, в Кинтана Роо, это пилообразные контуры. Учитывая наш относительный вес со спаркой,  просто не эффективно использовать легкие, а не компенсатор для изменения плавучести. Другим отличием является стиль погружения. Погружения в пещерах зачастую включает в себя погружение на определенное расстояние, в то время как в любительских погружениях мы в основном ограничиваем наши перемещения на небольшие расстояния. Другими словами, одной из наиболее важных частей кейв тренинга является обучение технике погружения наиболее эффективно и экономично. Не для того, что бы поставить рекорд, но например, обеспечить спокойное всплытие после непредвиденного происшествия, с достаточным резервом газа.

Расслабленый и постоянный ритм дыхания, это является ключевым элементом, гарантирующим стабильную плавучесть, снижением потребления газа и минимизированием содержания углекислого газа. Наличие слишком большого количества углекислого газа в крови имеет множество негативных последствий, таких как головная боль, повышенная частота дыхания, так как тело старается избавиться от него, а также повышает риск возникновения токсического синдрома и наркоза посредством инертных газов.
Почему плавучесть так важна? Думаю, если Вы читаете это, уже очень хорошо знаете, но в целом, это должно быть второй привычкой, потому что нам нужно сконцентрироваться на других вещах, например на напарниках, прокладке маршрута, на знании пещеры и так далее. Стабильность в воде является платформой, на которой строится все остальное. В среде, где иногда всего лишь сантиметры отделяют баллоны от крайне изменчивой верхней поверхности пещеры, а грудную клетку от глубоких донных отложений этот навык является абсолютной необходимостью. 
Итак, что Вы можете сделать, чтобы подготовиться? Начните использовать инфлятор чаще, чем легкие, для изменения плавучести и научитесь выпускать воздух без заметного изменения Вашего положения в толще воды. Потренируйтесь неподвижно зависать, без наблюдения Ваших датчиков, только по ориентирам, а также попытайтесь ограничить глубинные колебания ног вверх и вниз. Начните чувствовать скорость Вашего подъема, опять же без показаний датчиков.

Положение в воде:

К сожалению, большинство любительских компенсаторов плавучести совмещенных с грузовым поясом спускает центр тяжести до точки, где невозможно поддерживать горизонтальное положение в воде - оптимальную позицию для любого типа погружения. Итак, что можно сделать? Купите компенсатор стиля крыло, уберите груз с пояса, и попробуйте переместить его выше, так чтобы в неподвижном состоянии получалась прямая линия от плеча до колена, параллельная дну. Заметьте, что Ваша спина должна быть выгнута.
Почему это играет такую важную роль? Во-первых, это уменьшает сопротивление воды, что очень удобно, если Вы хотите продвинуться сразу на три метра вперед всего одним гребком. Это также уменьшает напряжение и увеличивает эффективность, что еще более снижает потребление газа и противостоит удерживанию углекислого газа. Соответствующее горизонтальное положение в воде является обязательным для всех и используется для любой технике передвижения в пещерах, особенно для поворота «вертолетиком», движения «фрогом» и задний ход «фрогом» о которых мы поговорим немного позже.
В пещерах, где очень слабое течение, или его нет, это также помогает избежать заиливания, и за счет отсутствия движения воздуха внутри крыла, Ваша плавучесть будет более стабильной.
Большинство людей не привыкли, чтобы их головы находились так низко по отношению к туловищу, что зачастую дает чувство падения. В результате, это приводит к дискомфорту, что очень плохо, и приводит к другим проблемам. Во время ходьбы наш мозг располагается на верху, и именно поэтому, большинство студентов, практически мгновенно отступая от этого положения, сталкиваются с тяжелой задачей. Для того, чтобы оставаться в таком положении требуется определенная концентрация, и когда мы должны         сконцентрироваться на чем-либо еще, горизонтальное положение мгновенно исчезает.      
Представьте себе картину: из-за нехватки газа дайвер дышит из регулятора напарника, и моментально переходит в вертикальное положения просто от отсутствия привычки. В следствии чего происходит заиливание прохода, ситуация ухудшается, и как мы знаем, большинство несчастных случаев вызваны не одним, а несколькими факторами.
Привычка к этой позиции до начала курса, это посильная помощь, и кроме того, хорошие навыки плавучести, создают прекрасную основу.
Как можно проверить свое горизонтальное положение? Достаточно легко. Просто положив подбородок на грудь, и не переставая находиться в параллельном ко дну положении, Вы должны увидеть пространство за собой. И не беспокойтесь, если плечи теперь немного выше головы, так Вы просто избежите прикосновения ласт с потолком.

 Техника продвижения под водой:

Или как перемещать свое тело и все надетое на нем оборудование под водой. Представьте, что дайвер со спаркой это – автомобиль, у которого вместо плеч и колен четыре колеса.
Для того, чтобы припарковаться на ограниченном пространстве Вы должны уметь поворачиваться  на этом пространстве, двигаться вперед и назад. Нижеследующий текст – только краткое введение, скорее всего Вам также понадобиться сеанс с инструктором для улучшения навыков.
В пещере, что бы двигаться вперед, мы можем использовать три типа движений, в основном «улучшенное движение фрогом». Это движение немного изменено и улучшено тем, что во время подготовки к удару ластами мы раздвигаем ноги, согнутые в коленях, по горизонтали, вместо того чтобы просто опустить колени вниз. Это самой мощный вид движения ластами и имеет преимущество в продвижении вашего тела только вперед, а не вверх (как, например, при ударе ножницами) при этом поток воды от ласт направлен назад, а не вниз или вверх, не тревожа слой осадков. Здесь используется крупнейшая группа мышц, которые наиболее важны при продвижении на длинную дистанцию и правильно сделав это движение, Вы можете преодолеть три метра за одно движение. Движение «фрог» состоит из четырех основных элементов. Позиция номер один, когда мы находимся в неподвижном состоянии горизонтально, колени согнуты; два, когда мы раздвигаем наши ноги и пытаемся развести пятки как можно дальше друг от друга; три, поворачивая ласты так, чтобы создать как можно больше пространства для продвижения воды; и четыре, это наиболее трудное плавное круговое движение, при котором мы направляем воду назад, распрямляя  наши ноги и лодыжки полностью, и одновременно их сдвигая. Теперь, находясь в этом положении, мы скользим сквозь воду, дожидаемся замедления, и потом опять сгибаем коленей на 90 градусов, чтобы повторить движения сначала.
Измененные размашистые движения (modified flutter), работают также как и обычные (flutter kick), за исключением того, что ласты не опускаются ниже тела. Таким образом, я сгибаю колени вверх и вниз, и при этом постоянно держа ласты параллельно нижней поверхности. Основное отличие от движения «фрог» состоит в том, что вместо того чтобы толкать воду ступней, мы делаем это верхней частью ласты, а также движением одной ноги, а не двумя. Это означает, что одна нога нас тормозит, за счет сопротивления воды, а другая толкает. Это движение очень удобно в туннелях каньонного типа, где недостаточно горизонтального пространства, для более эффективного движения «фрог».

И наконец, движение ступней (shuffle kick). Это движение мы используем в тесных и хрупких местах, а также для впереди плывущего дайвера в тесном контакте с напарником, при прохождении ограничений. В основном, это такое же движение, как и размашистое передвижение, только все движения осуществляются лодыжками, оставляя бедра и икры неподвижными. Правильно сделав это движение, можно получить огромную скорость с небольшим усилием и в ограниченном пространстве. Движение очень похоже, например, на постукивание ногой в ритм во время игры на гитаре.
Как упоминалось выше, существует две специальные техники для дайвинга в пещере: «поворот вертолетиком» и задний ход «фрогом», оба как движение в обратном направлении.
«Поворот вертолетиком» осуществляется двумя способами, медленно и быстро. При медленном варианте не нужно делать ничего нового, то же движение «фрогом», только одной ногой, в то время как другая остается на месте и выполняет функцию тормоза. Правила просты, двигаетесь при помощи правой ноги, и поворачиваетесь налево и наоборот. Это похоже на движение в гребной лодке.
При быстром варианте нужно делать движение «фрогом» одной ногой, выполняя возвратное движение другой, опять как в гребной лодке.
Это единственный способ развернуться, не переходя в вертикальное положение, и поэтому так чрезвычайно важно. Так как мы всегда разворачиваемся лицом к ходовой линии, очень важно уметь поворачиваться в обоих направлениях одинаково эффективно.
Задний ход «фрогом» для многих является  черной магией и источником для легенд. Это наверняка самое трудное из всех движений, но при помощи инструктора и тренировок это достижимо для каждого. Как и для всех координационных движений, Вам понадобиться время, для создания мышечной памяти, но по сравнению с обучением игре на музыкальном инструменте, например, это действительно легко. 
Помня четыре шага в движении «фрогом», просто повторите их в обратном направлении. Вместо проталкивания воды в заднем направлении при помощи ступни, вытолкните ее в стороны при помощи верхней части ласт. Важно не опускать колени, а перемещать воду в стороны. Начните с выпрямленными ногами и пятками, сведенными вместе, выверните колени, ногами образовав букву «О». Затем раздвиньте ноги и согните колени, чтобы они были в позиции движения «фрог». Не двигаясь, позвольте движущей силе переместить Вас немного назад, до того как опять осторожно сдвинуть ноги и убедиться, что ласты выровнены в воде и не продвигают Вас вперед.
Почему важно плыть возвратными движениями? В основном, для того, чтобы остановить  движение вперед, что, безусловно, поможет поддерживать контакт с напарниками, в определенные моменты. Также это поможет оставаться на одном месте, а именно рядом с ходовым концом, и напарниками во время выполнения  других задач.

Итак, как можно потренироваться дома. Начните лежа, на плоской поверхности, что помешает Вам изогнуть бедра и опустить колени. Наденьте ласты и практикуйте движения, если есть возможность, то рядом с зеркалом, чтобы видеть движения Ваших ног. Затем, зайдите в бассейн без оборудования, только с ластами, маской и трубкой. Держитесь за край бассейна и потренируйте движения в воде. В воде Вы мгновенно поймете, что у Вас получается, а что нет. Если есть возможность, попросите друзей снять Вас на видео, чтобы Вы могли просмотреть и скорректировать движения самостоятельно. И последнее, тренируйтесь в полном оборудовании и помните, хорошая плавучесть и горизонтальное положение под водой, являются платформой для того, чтобы дать себе возможность сконцентрироваться над движениями ног. Как только у Вас начнет получаться, положите что-нибудь на дно, например катушку, и постарайтесь оставаться в неподвижном положении над ней так долго, как можете, с допустимым небольшим движением.

Наслаждайтесь, тренируясь, и помните, это не получится легко, но как только пойдет, Вы поймете, это как езда на велосипеде.
Если Вы придете на курс уже с этими навыками и в хорошей форме, Вы потратите меньше времени в открытой воде и быстрее получите возможность зайти в пещеру. И Вам нужно будет более подробно заняться вопросами прокладки маршрута, напарниками и т.п. Так же Ваш инструктор сможет потратить больше времени, показывая Вам тонкости пещерного дайвинга, а, не исправляя Вашу плавучесть, положение в воде и техники передвижения.

Если у Вас есть вопросы о том, как подготовиться, или тренироваться, не стесняйтесь и напишите мне. Мне было нелегко все это освоить, поэтому я знаю пару хороших трюков.

Сделайте дайвинг искусством.
Патрик

Tanks

Configurations vary but easy deployment, easy location and identification has to be of paramount importance. Double tanks with isolator manifold are commonly used, however in recreational diving independent tanks are used. A sufficient quantity of gas must be carried by the diver to allow completion of the planned bottom time, utilizing the minimum gas management rule for the type of diving enrolled in. Furthermore, this gas supply must allow for gas matching between divers.

The first item that needs to be addressed in tank selection for a specific dive is the needed gas supply and with it tank size resulting from factors such as body size, gas consumption, planned depth and duration. Experience has taught that the most logical approach to the question of gas supply can be best summed up by the statement in why there is a need for gas supply requirements. The first step in planning a dive involves computing the amount of gas needed for the dive. This includes primary mixes and decompression mixes. Decompression systems should provide a sufficient volume of gas to complete all appropriate stops with a minimum reserve supply. Each decompression gas cylinder must be appropriately marked as to its use, breathing gas and M.O.D. It’s also suggested that regulators be color coded or coded for easy identification. Mouthpieces should be protected to prevent from accidentally being used with the wrong mix during your decompression at the wrong depth.

The choice between tank materials will be dedicated by the environment and thermal considerations. The diver should be balanced in a way that he or she is neutrally buoyant with empty tanks at 10 feet / 3 Meter, comfortable for prolonged periods of time. In order to archive this diver must balance and trim their rig carefully for the environment one is diving in. Ample emergency gas volumes must be carried for the type of diving engaged in plus a redundant buoyancy device such as a dry suit or back up BCD must be worn on deeper dives.

Steel Tanks

While steel tanks are a great choice for cold water, wreck or cave diving due to their larger volume 104 or 121 cft / 15 or 18 ltr where the weight of the tanks is partially offset by the thermal protection due to dry suit sworn by most divers. Helium based breathing gases do affect weight and buoyancy underwater and must be taken into account.

Aluminum Tanks

Warm water, wet suit ocean diving is best done with aluminum 80 cft / 12 ltr tanks due to their lesser weight and with it lesser negative buoyancy at the bottom phase of the dive. If more gas is needed a aluminum stage tank should be added to fulfill breathing gas requirements.

Harness and Backplate / Softpack

While many dive gear manufacturers offering traditional BCD’s for recreational diving most wreck, technical or cave divers prefer the harness and backplate / softpack combination. Most recreational BCD’s can not be adapted for advanced forms of diving such as cave, technical and wreck diving and when a diver is ready to proceed to higher levels of training a new set of gear has to be purchased. Harness and backplate / softpack combinations eliminate that problem since they can be easily adapted for single tank recreational diving or technical and cave diving activities that may lay n the future.

Harness

A harness is used to attach the tanks to the diver sandwiching the wing style BCD between the tanks and the harness. The harness is attached to a backplate or a soft pack, which is then attached to the single or double tanks. A wing style buoyancy compensator has to be worn, attached to it a low pressure power inflator. The webbing attached to the backplate should be of the all through type with no connections, easy clips, rings or fast buckles intersecting the webbing. Such fasteners who make it easier to get into and out of the diving rig are potential failure points with disastrous potential to loose all of the equipment during the dive and in the long run it is more economic to change a basic webbing when it is worn out.

The crotch strap that has to be worn in order to prevent the unit from “riding up” should be without a clip but made from the closed loop type in order to prevent breaking clips during or prior to a dive. Crotch straps can be used as we for gear storage when a d-ring is attached to it at the back, or to attach a scooter to a d-ring in the front. The all one through webbing allows as well the placement of d-rings at any location throughout the harness to accommodate backup lights, stage tanks on the chest d-rings and gauges or reels on the waist d-ring.

Backplate

Backplate’s are made out of ABS plastic, aluminum or stainless steel. The stainless steel backplate is the most popular one since it is a little heavier and compensates for some of the weight a diver may needs to carry when diving with positive tanks or a dry suit.

Soft packs

The softpack harness systems on the market have the advantage of being well adaptable for the type of diving one is involved in ranging from recreational single tank diving to technical, wreck or cave diving to advanced forms of cave diving such as sidemount diving. The potential downside is the fast clips on the chest that could a dive fast out of the rig but could fail before or during a dive and be difficult or impossible to repair.

Buoyancy device

Back mounted wing style wing’s are known for superior trim characteristics in recreational openwater diving and advanced diving while openwater style BCD’s are not recommended due to limited lift capabilities, buoyancy characteristics, tank attachments and d-ring placement specially in advanced forms of diving such as technical, wreck or cave diving. The lift of the wing needed is depending on equipment weight, tank weight full and empty,  scooters and stages if worn. Oversized wings and tight bungeed wings do have a tendency to create more drag in the water resulting in more energy spend and potential exhaustion of divers. All wing inflator and dry suit inflators if used should have the same connector to insure interchangeability of hoses and gas supply.

Wing style BCD

Wings are coming in a variety of lift capacities, styles and some sport a choice of features. The chosen wing should have the right amount of lift for the equipment, tanks and environment dived in. The corrugated hoses should be not as long as to touch the floor when diving close to the bottom and stirring up silt, damaging the environment or entangling the diver. Shorter size corrugated hoses are available to change the log size hose. In demanding environments such as inside wrecks or caves it is a good idea to have the inner bladder protected against puncture. Dump valves in the corrugated hose assembly can fail and present a potential problem. Dump valves on the bottom of the wing should be streamlined by cutting of the plastic knob to prevent entanglement.

Back up wings are recommended in deep dive applications or a dry suit can be used as a back up buoyancy device however dual bagged bladders are potentially creating added drag and degrade performance, this will in the end may slightly increase in gas consumption. The advantage of a dual bladder in the event of a BC failure is that the diver may still function normally and make a safe ascent. Diving with a single bagged bladder provides less drag and maximizes performance. Given a choice, most divers would prefer a configuration that reduces drag. But, if there’s a chance the single bladder could fail and this failure could be life threatening, it makes good sense to sacrifice being streamlined by increasing redundancy. By opting for greater redundancy, divers need to recognize this will increase their gas consumption. They must also realize it’s going to slow them down a little. Keep in mind dry suits can be used as a backup buoyancy control device.

Lift

Depending on fresh water or salt water diving, choice of tanks used, including exposure suit selection the amount of weight can vary greatly. Carrying to much weight should be avoided while conducting buoyancy checks before diving activity striving for a balanced rip that can be use with neither to much weight or to much gas in the lifting device. Drop weights can be used in stable depth caves and left close to the entrance when maximum depth is reached. V-weights can be used for double tanks used in-between double tanks and kept in place by the wing and harness while weight belts should be avoided.