Question About MK V

ive been reading up alot on historical diving, and the MK V.. or Mark 5 has been quite the topic.

But i do have a question i couldnt find an answer to. I notice that when they do a water entry in full suit, helmet, etc. They usually do a giant stride entry, and with 200+ lb's of weight on, they sink right to the bottom.

What about changing pressure and the ears? Or do they just deal with the pain till they get to the bottom.

Ingolf:

ive been reading up alot on historical diving, and the MK V.. or Mark 5 has been quite the topic.

But i do have a question i couldnt find an answer to. I notice that when they do a water entry in full suit, helmet, etc. They usually do a giant stride entry, and with 200+ lb's of weight on, they sink right to the bottom.

What about changing pressure and the ears? Or do they just deal with the pain till they get to the bottom.

Click to expand...

First off the giant stride was/is used but not all that often but if you can you use the ladder. It doesn’t matter how you enter the water you’re not going straight to the bottom. That unit is extremely buoyant.

One problem that must be over come in the MK5 is not blowing up. It is very easy to lose control of the suit and blow to the surface. It’s a rare occurrence but can and has happened.

Clearing is not a problem. If you're one that has to pinch your nose you just smash your nose against the side of the hat and blow. Outside of training you can chew gum or do something else.

If you just put up with the pain on the way down having a com system would be useless because you’d blow your drums if it was very deep at all.

By the way, the MK5 is still being used today so it isn’t quite the relic some think it is. It is a very good heavy unit that is very comfortable on the bottom. Much more so than all the newer units.

Hat 56-66 pounds
Suit 18
Boots 35
Weight belt 84
Plus what ever goodies you take with you.

The air unit is much lighter than the HEO2 unit which is around 100# heavier and has a hoist lifting ring on the top of the hat.

Gary D.

Expanding on what Gary said, the suit and helmet are mated together through the breast plate. There is no neck seal, the diver can manipulate the amount of air coming in and the amount being exhausted inflating the suit.

When entering the water it is similar to entering with out burping any air from a drysuit, the water pressure once you enter helps to force the air up into the helmet and out of the suit.

If you have a full helmet wouldn’t equalizing the pressure be easier if not required since you are in an air environment like flying? I thought that was the concept behind the masks with the ear cover things that connect to the mask to provide and air pocket.

Berdman:

If you have a full helmet wouldn’t equalizing the pressure be easier if not required since you are in an air environment like flying? I thought that was the concept behind the masks with the ear cover things that connect to the mask to provide and air pocket.

Click to expand...

No, just because your ears are covered doesn't eliminate equalizing. You’re exposed to the same pressure as your surroundings just like in SCUBA. The MK5 is a soft but thick fabric suit.

In order to be a one atmosphere suit it has to be a hard suit like a submarine, Jim Suit, Newt Suit or something on that order.

Gary D.

Ingolf:

They usually do a giant stride entry, and with 200+ lb's of weight on, they sink right to the bottom.
.

Click to expand...

Most will use a lader or a divers stage to get into the water. A stage might take you down to about 30' when you step off and start your decent. The decents are slow so that you can add air to the suit as you drop. One of the major dangers is an uncontroled drop where you do not have time to adjust your suit. The resulting suit squeze can put you into the helment as mush.

Then the tender has to wash your jelly out of it.

Gilldiver:

Most will use a lader or a divers stage to get into the water. A stage might take you down to about 30' when you step off and start your decent. The decents are slow so that you can add air to the suit as you drop. One of the major dangers is an uncontroled drop where you do not have time to adjust your suit. The resulting suit squeze can put you into the helment as mush.

Then the tender has to wash your jelly out of it.

Click to expand...

Let's not forget that when you hit the water your tender will snug your line and that will keep you from descending until you request some slack.

What’s interesting with the MK5 is when you blow a glove off. If you're using the three finger mittens (not open hand seals) they are glued on right around the elbow area, depending on how tall you are. When the glove blows off, the suit floods rather quickly.

How many of you know what happens from that point? Forget the boys going south for the winter and the pucker factor going to Saturn, those are a given.

Ref. getting squeezed into the hat, that can happen. BUT, the depth has to be so great that the occupant would be dead long before that would ever happen and you would have run out of hose and com line a long time before that.

Gary D.

The college dive program I teach for justhad a MK V complete with manual pump compressor donated. I am salivating at the prospect of diving with it.

Trtldvr
Dive A.L.I.V.E.

trtldvr:

The college dive program I teach for justhad a MK V complete with manual pump compressor donated. I am salivating at the prospect of diving with it.

Trtldvr
Dive A.L.I.V.E.

Click to expand...

Don't just jump in and start playing with it. It can be a great dive or a real hand full if you’re not careful even in a pool, especially with an old hand pump. Should the pump fail you should and I emphasize should have 5 to 10 minutes of air before a color change.

Not only does the diver need to be trained but the tenders (at least 2) need to be trained as well.

My best dives were in the MK5. It is in a world all its own.

If it came with a 110 volt com box DO NOT USE IT! A small mistake can kill everyone close to it. If it has a 12 volt talk all you want to.

Enjoy

Gary D.