News
Being Horizontal… ‘Cave Trim’ – the elusive goal
Watch a group of well-trained divers in the water — especially cave divers or technical divers — and you’ll notice they look a little different to most casual sport divers.
How different?
Well, the cave/technical/well-trained sport divers will be lying on the water (usually horizontal) rather than standing in it. Here’s what I mean:
A typical cave diver in trim… lying on the water
Photo: Tom St George
And here’s a picture of a group with a different in-water attitude:
A diver enjoying the water but working hard…
Photo: Dean McConnachie
So, let’s assume you’re not looking at those pictures and saying to yourself: “What’s the big deal?” Or “I can’t see any difference.”
Given that, let’s also assume you are interested in finding out why cave trim is preferred over the other. It’s not that anything other than horizontal is wrong. It’s just there’s something easier and better. (For the record, horizontal trim is not always exactly horizontal — occasionally the correct attitude in the water is head or feet down at varying angles for short periods — but it is the default.
Reason one to be horizontal: moving through the water is easier. You are streamlined and therefore water resistance moving ahead and backwards is at a minimum. Even with extra gear (more bottles, pockets full of tools and spanners, a pouch with backup mask, spare dive computer, lights, bits of string and a chicken sandwich), moving through the water in any direction is easier compared to swimming at it full-frontal. When a diver is streamlined, the thrust from each and every fin kick is translated into graceful movement. Progress from point A to point B and back again is more efficient, less work, uses less energy, uses less gas.
Reason two: when a diver’s flat in the water, she meets maximum water resistance going up or down. This helps her maintain position in the water column. Of course, this is a small effect compared to having buoyancy dialled in, but it’s nevertheless a factor.
One salient point when comparing cave trim to fins down orientation, is that being horizontal teaches good habits regarding buoyancy control. There is no temptation to kick to stay in place as there is with fins-down orientation. (For example, although the group picture above isn’t a video, I’d lay dollars to donuts that the two divers on the left and the one on the right are all working hard to maintain their position in the water column while the picture is being taken. They seem to have poor buoyancy control, and staying in place is an effort for them.
The cave diver pictured above is motionless, and literally hanging in the water waiting for the photographer — Tom St. George — to signal “okay. Got it!”)
Reason three: a diver in horizontal trim is much less likely to stir up silt and mud or damage whatever is below them. In fact, when using the correct propulsion technique (frog kick generally) and by keeping the knees bent and thighs parallel to her lateral line, a diver can be a hand’s breadth from the bottom and move without disturbing anything at all. This diagram may help illustrate the point.
When in horizontal trim, arch the back slightly by clenching your butt cheeks… think “Flamenco Dancer Skydiving.”
Illustration courtesy of Andy Davis, Scuba Tech Philippines
Okay, so how does one attain horizontal trim?
In a word: practice.
In more detail: commitment and practice!
Practice needs little explanation. Be patient, spend the time. A great approach is to dedicate a few dives to nothing but working on trim.
For an in-water exercise, get to a pool or shallow, calm waters, and dive with a buddy who has an underwater video camera to track your progress. Start by resting prone on a flat ledge or the pool bottom and gradually add a little lift to your buoyancy cell.
Critical to mastery is sticking to it (that’s the commitment), that and understanding the relationship between four things: gravity, buoyancy, you, your gear.
Essentially, you need to balance each of these things to come up with a perfect result. Luckily, two of them are constants and pull in exactly opposite directions. Gravity pulls you deeper, buoyancy pulls you towards the surface.
Simple… well, almost. What complicates matters are the other two things: you and the gear you are wearing.
Now let’s just say for brevity, you have reached the point where you have gravity and buoyancy perfectly balanced. Something called neutral buoyancy. You are not overweighted. You are not under-weighted. And in shallow water you are able to hover without moving your hands and feet.
At this point — hovering — you’re off to a great start. But now you need to get horizontal and stay there without moving your hands or feet (don’t scull, don’t swim, just hang in the water). Try it. If you’re lucky, it will work. Most likely though you’ll either tilt head down or feet down.
Let’s think about that situation for a minute.
As a for instance, say you need two kilos of ballast (lead weight) to achieve neutrality. These weights are over and above the ballast that’s a result of your scuba cylinders, lights, reels, and all the other crap we carry with us on a dive.
Now, divers usually carry lead ballast around their waist, so let’s says yours is about your mid-point. Now consider what would happen if we were to move that weight to the ends of your fins. Your feet would naturally swing down pulling you, your body, your kit, into a straight up and down orientation. Kind of similar to what happens when a “robust” child get on one end of a teeter-totter (a see-saw) and the “runt of the litter” is sitting on the opposite end.
Okay, so what would happen if you were silly enough to put the weights on your mask strap. Well, to begin with you’d orient head down and then your mask would most likely fall off. Goodbye mask. But if we think about the see-saw situation, same deal except now runt’s pet elephant is sitting on his lap and Robusto is up in the air.
You get the point. You are dealing with a lever. To achieve balance, either the weights on both ends have to be similar, or the distance from the balance point — the fulcrum — has to compensate for any difference. That’s to say, moving stuff that sinks in the water — weights in this instance, but also all the other bits and pieces of kit — is going to have a direct effect on in-water orientation.
Weights sink, so do scuba cylinders, lights, cameras, and a whole lot more including the gas we breathe (more than 2.5 kilos of “air” in a standard aluminium 11-litre tank for example). Understanding that moving each of these things away from your balance point has the potential to influence trim is key.
To achieve cave trim you want balance. Moving things around — even swapping light fins for heavier ones — can make that happen… or not.
But before that, you perhaps should consider things that have an effect on buoyancy: lungs, buoyancy cell (BCD, wing, etc.), drysuit, thick wetsuit. And each of these is a variable.
Also — and this is where things get interesting — things that are buoyant supply lift and the location of that lift can have an influence on trim as well. (Ask a new drysuit diver about their experience with floaty feet.)
You can experience something similar by moving a cylinder up and down in its retaining straps on a standard BCD.
All this serves to show us that the see-saw analogy used earlier may actually be an over simplification. It would be better to think of a fully kitted diver as a beam with a variable balance point rather than a simple lever with a fixed fulcrum.
Hang on. This has started to get a little over-the-top and way too complicated to explain without using Venn diagrams and video. No worries. Let’s stop now while we’re ahead because in truth, the take-away is essentially unchanged. You have the basics. Now let’s get in the water and practice.
Steve Lewis’s new book, Death in Number Two Shaft: the underwater exploration of Newfoundland’s Bell Island Mine, is available now on Steve’s website or from Amazon UK.
Find out more about Steve at www.techdivertraining.org.
Ho Ho Ho! Vobster Quay’s recording-breaking charity Santa diving event returns on Sunday 15th December 2024 for another round of festive fundraising frivolities. Run in aid of the Royal National Lifeboat Institution (RNLI) and Help For Heroes, this ever-popular annual fundraising event aims to raise sack-loads of cash for these two very deserving charities.
Divers of all levels are invited to grab their Santa outfits – and as much festive cheer as they can muster – and head down to Vobster Quay near Mells, Somerset for a mass sponsored Santa dive in aid of charity. In previous years, the event has attracted divers from the far corners of the UK to join in the festive merriment for a final festive dive before the Christmas and New Year break. Back in 2015, the event smashed the world record for the most Santa divers with 188 divers taking to the waters donning their festive finery – a record that remains unbeaten to this day!
Vobster Santas isn’t just about setting records – it’s also about raising some serious cash for charity. Vobster Quay encourages all divers to get into the spirit of the season to raise much-needed funds for two very deserving charities – the Royal National Lifeboat Institution (RNLI) and Help For Heroes.
Through individual sponsorship and online donations, divers can invite their friends, family and work colleagues to sponsor them to plunge into the balmy waters of Vobster Quay dressed in full festive finery. Since the very first Santa dive in 2007, the event has raised over £52,000 for charity. “It’s been over 17 years since the very first charity Santa dive took place at Vobster Quay and every year the event just keeps getting bigger and better” enthused Vobster Quay owner, Amy Stanton.
“Vobster Santas is a great way for divers to say a massive thank you to the both the RNLI and Help For Heroes – two very deserving charities close to our hearts. We’re immensely proud of all that Vobster Santas has achieved and hope that even more divers will join this year’s event on Sunday 15th December. I’m confident that we can make Vobster Santas 2024 the biggest yet!”.
Divers wishing to participate can get involved by simply registering their attendance at
www.vobster.com/event-vobstersantas.php.
Blogs
Dive into Adventure at Hideaway Beach Resort & Spa: The Ultimate Diving Destination in the Maldives
Tucked away in the remote northern Haa Alifu Atoll, Hideaway Beach Resort & Spa is a premier destination for anyone seeking an unforgettable underwater experience. With over 30 dive sites to explore, divers of all levels can witness the unique and mesmerising beauty of the underwater world. Whether you’re a seasoned diver or new to the sport, Hideaway offers an exceptional diving adventure that is not to be missed.
Explore the Beauty Beneath the Surface
Hideaway is perfectly situated near some of the most spectacular dive sites in the Maldives. The dive school and team at Hideaway offer a very personalised experience to ensure each diver gets an interactive, immersive experience.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
Unique dive spots such as Theefaridhoo Thila (Heaven and Hell) as one of the 50 best dive sites in the whole of the Maldives, known for its beautiful soft coral gardens.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
As the resort is located next to a channel which gives guests surprise visits from eagle rays, manta rays, guitar sharks and more.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
One of the standout features of diving in the Haa Alifu Atoll is the abundance of rare and exotic marine species. The area is known for sightings of whale sharks, manta rays, turtles, and a variety of colorful reef fish. Diving at Hideaway Beach Resort & Spa offers a rare opportunity to encounter these creatures in their natural habitat, creating lifelong memories for guests.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
Whether you’re exploring deep coral gardens, dramatic overhangs, or vibrant reef walls, each dive offers something new and exciting. The visibility in the Maldives is exceptional, often exceeding 30 meters, making it ideal for both underwater photography and general exploration.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
Diving for All Levels
At Hideaway, we believe that everyone should have the opportunity to experience the thrill of diving. That’s why we cater to divers of all levels, from beginners to experienced professionals. Our professional dive center, led by expert instructors, offers a range of courses and guided dives. If you’re new to diving, you can start with an introductory course that will teach you the basics of scuba diving in a safe and controlled environment.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
For more experienced divers, we offer advanced dive courses and guided excursions to some of the more challenging dive sites. Our instructors are knowledgeable and passionate about the local marine life, ensuring that every dive is not only safe but also informative and enjoyable.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
Exclusive Diving Offer
To make your stay even more unforgettable, Hideaway is offering an exclusive diving package designed to enhance your experience both above and below the water. When you book a minimum 7-night stay, you’ll receive:
- 35% discount on room rates.
- Complimentary diving: 3 dives per person for 2 guests, allowing you to experience the beauty of the Maldives underwater world.
- Free meal plan upgrade: enjoy a complimentary upgrade from Bed & Breakfast to Half Board, or from Half Board to Full Board. Guests who prefer the White Platinum Plan (WPP) can avail it at a discounted rate.
This incredible offer provides the perfect opportunity to experience world-class diving while enjoying all the luxury and comfort that Hideaway Beach Resort & Spa is known for.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
Combinable Offers for Even More Value
This diving offer can also be combined with our Anniversary and Honeymoon offers, allowing you to create the perfect celebration package. Whether you’re celebrating a milestone or simply seeking a romantic getaway, this offer ensures that you can enjoy the best of both worlds – luxurious accommodations and unforgettable diving adventures.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
Terms & Conditions
- This offer is available exclusively for bookings made through the official Hideaway Beach Resort & Spa website using a specific booking code.
- The offer cannot be combined with other promotions available on the website or through other channels, nor can it be redeemed for cash.
- All dives are subject to weather conditions, ensuring the safety and enjoyment of all guests.
- Black-out dates: This offer is not available from 24th December 2024 to 9th January 2025.
To book this exquisite offer, use the Promo Code: SCUBA24FD
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
Hideaway is not just a resort; it’s a sanctuary for those seeking peace, adventure, and luxury. With spacious villas, private pools, and world-class dining options, the resort offers everything you need for a perfect holiday. From tennis, golf, gym, cycling to the exquisite underwater activities, unique dining options, Hideaway has something for everyone. And for diving enthusiasts, it provides an unparalleled opportunity to explore some of the most beautiful dive sites in the world.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
Our dive center is fully equipped with state-of-the-art gear, ensuring that every dive is safe, comfortable, and enjoyable. Our instructors are passionate about the underwater world and are eager to share their knowledge with you, whether it’s your first dive or your 100th.
Email: reservations@hideawaybeachmaldives.com / Call: +960 650-1515 / Website: www.hideawaybeachmaldives.com
The Ultimate Dive Adventure Awaits
If you’re looking for an unforgettable diving holiday in the Maldives, look no further than Hideaway Beach Resort & Spa. With over 30 dive sites, unique marine life, and exclusive offers, we provide the ultimate underwater experience. Whether you’re celebrating a special occasion or simply seeking adventure, our diving package offers exceptional value and incredible memories.
Book now through our official website to take advantage of this exclusive offer and prepare for the dive adventure of a lifetime.
Email: reservations@hideawaybeachmaldives.com
Call: +960 650-1515
Website: www.hideawaybeachmaldives.com
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