Using a reef hook with a Travel BCD

[james_bond_007]

Main reason at looking at the Air Travel is Lift is #36 vs Travelight's #20.

Aside from the extra lift, it implies, at least to me, that if the Air Travel is rated 80% more buoyant, it can lift/buoy a heavier load. Thus it might be built a bit sturdier, as well. (...but I'm reading into things a bit)

PS
I promise to look into all the other BCD suggestions, but I still want to get this answered.
DAN_T has given me the best info so far, but for a similar Cressi product.

 

[james_bond_007]

If you want a tougher travel BC look at the Scubapro Lighthawk. Leisurepro.com has the 2013 model for $249. It has 4 metal d-rings.

From Leisure Pro:

"Two movable accessory pockets for storage and strategically placed plastic D-rings for attachment points allow you to bring all the extras that make diving comfortable and fun."
​

But from the ScubaPro site

", and four aluminum D-rings provide convenient clip-on points for additional gear."​

..seems to be a pattern here

 

[Tippytoes12]

I have used reef hooks with mine in Raja Apat and inches Maldives twice without any issue. The only time I have felt that a backplate would be useful was in Dardalus in the Southern. Red Sea where there is a longish dingy ride to the top of the reef.....I felt that a back plate would have been better.

With a travel. BCD , regulator , fins , wetsuit etc. etc my gear weighs just about the 20 kg weight limit for anyfor any airlines.

 

[diversteve]

From Leisure Pro:

"Two movable accessory pockets for storage and strategically placed plastic D-rings for attachment points allow you to bring all the extras that make diving comfortable and fun."
​

But from the ScubaPro site

", and four aluminum D-rings provide convenient clip-on points for additional gear."​

That might be my mistake, the 2013 model has plastic d-rings but the newer version now being sold by Scubapro has aluminum d-rings.

One thing you could do is fabricate a 3 point harness and clip two of them to the d-rings on either side of the bc. Most of the reef hooks a quick google search brings up show a rope with a snaphook of some sort so splitting that between the two connect points might distribute the weight more uniformly.

I really do think you're overthinking it though - the function of a reef hook is more to hold the diver securely in place w/o the need to wedge fins in the coral or grab it with gloved hands than it is to keep one from being blown away. Outside of Blue Corner I don't know of another dive site where one is even required.

 

[james_bond_007]

I really do think you're overthinking it though - the function of a reef hook is more to hold the diver securely in place w/o the need to wedge fins in the coral or grab it with gloved hands than it is to keep one from being blown away. Outside of Blue Corner I don't know of another dive site where one is even required.

I'm planing on going to Cozumel. I'm told (it maybe just BS), but for taking pictures, reef hooks are recommended.
If the community has input on this, I would appreciate your opinions.

One thing you could do is fabricate a 3 point harness and clip two of them to the d-rings on either side of the bc. Most of the reef hooks a quick google search brings up show a rope with a snaphook of some sort so splitting that between the two connect points might distribute the weight more uniformly.

With the diver hooked on by the BCD, the current causes a force to be applied to both the D-rings and the webbing to which they are attached. The bigger the diver, the more force on the ring/webbing.
Seems like a diver in a current would apply much more force on these points than just a flashlight clipped to the D-Ring.

My concern is for safety and is twofold:
1) will plastic D rings be sufficient to not break under this force ?
2) will the webbing be sufficient to not break, rip, etc. under this force ?

So the question still is "Did the manufacturer design the Travel BCDs D-rings to sustain the force of a diver in a current or just the weight of a flashlight clipped on ?"

I have a question out to the mfgs.

 

[james_bond_007]

LeisurePro says there is a mistake on their website.
The Air Travel has SS D-rings (consistent with the Cressi site).

 

[Cali_diver]

I'm planing on going to Cozumel. I'm told (it maybe just BS), but for taking pictures, reef hooks are recommended.
If the community has input on this, I would appreciate your opinions.

I have been to Cozumel many times and have never used a reef hook. Not even sure they would be permitted within the park. That being said, we have had a Zuma in the family for at least 5 years and it has performed nicely. All D rings still strong.

 

[beaverdivers]

Reef hooks are not allowed to be used within the park in Cozumel. I have used reef hooks with both the GO & Litehawk travel B.C. without a problem in other parts of the world. However, I don't use the D-rings. I attach the reef hook to the chest strap. I feel it gives me a better center for lift & control.

 

[gr8jab]

With the diver hooked on by the BCD, the current causes a force to be applied to both the D-rings and the webbing to which they are attached. The bigger the diver, the more force on the ring/webbing.

bigger = volume or mass?

I ask kindly with a contemplative look on my face...

If you meant volume, probably correct, since that implies the diver is less streamline.
If you meant mass, probably incorrect, see below.

A neutrally buoyant diver on a reef hook would exert force based on the water that is hitting him. His mass is moot. The more streamline the diver, the less force on the D-rings.

F=ma, where:

m = mass of the water hitting the diver
a = acceleration (deceleration) of the water as it hits the diver
F = force on the D-rings.​

_____________________________________________

Contrarily:

Now, if he is moving with the current, sets the hook, and comes to an immediate stop, the transient force on the d-rings is proportional to his speed and his mass. Of course, it also depends on how elastic the rope is...

F=ma, where

m = mass of the diver
a = acceleration (deceleration) of the diver
F= force on the d-rings​

Since acceleration is 'change in velocity per unit time':

• Higher velocity (current) means higher acceleration, and higher force
• A more elastic rope means longer time to change speed, and lower acceleration, and lower force.

Oh, and you can always use the term 'accelerate' when talking about the physics. Deceleration is just negate acceleration.

 

[james_bond_007]

Reef hooks are not allowed to be used within the park in Cozumel. I have used reef hooks with both the GO & Litehawk travel B.C. without a problem in other parts of the world. However, I don't use the D-rings. I attach the reef hook to the chest strap. I feel it gives me a better center for lift & control.

I knew about the National Park (no gloves, no knifes, no reef hooks etc.) . I was told (again, I appreciate the comments from people here that have Been There and Done That) that there are some areas outside the park where hooks are used.

If this is not true, then I have no worries. I just won't use one there, anywhere.