U.S. Navy Mark V
Diving Helmet Page
SAFETY WARNING
NEVER, EVER DIVE A HELMET UNLESS YOU ARE ABSOLUTELY SURE IT IS
GENUINE AND IN PROPER WORKING CONDITION. Replica helmets are not designed or
built for actual use. Attempting to dive a replica helmet could result in
serious injury or death. Only dive after you have received the proper training.
Notice to potential helmet purchasers
Many replica Mark V helmets are currently on the market. These helmets often have authentic looking tags with the names of legitimate manufacturers on them. The most common replica has a "Morse" Diving nametag, and there is a replica around with a "Diving Equipment & Supply" nametag. The most blatant fake is one bearing a nametag which says "Brooklyn Navy Yard 1911". The Mark V didn't even enter service till 1916. People have purchased replica helmets believing they are genuine. When considering the purchase of any diving helmet do some research before you commit.
Some things to look for are the telephone cup set back on the helmet top. Copper sheet used to make exhaust banana tube instead of the real cast brass tube. The top window set too far up on the top. Window frames held in with screws. No ductwork inside the helmet. The top and breastplate held together by set screws instead of interrupted threads. Two piece air and communication elbows. A front door pin which is not removable. A "stove pipe' appearance to the breastplate instead of the rounded appearance of a genuine Mark V breastplate. The Spitcock stem is held in with a large round nut instead of a washer and hex nut.
"Morse" Replica Mark V "Diving Equipment" Replica Mark V
Here are some close up photos of the reproduction Mark V helmet we used to sell.
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Click on the picture to enlarge. Use your back button to return.
What is a U.S. Navy Mark V Diving Helmet?
Below are some things to look for in a genuine Mark V Helmet.
History
At the turn of the 20th century the U.S. Navy didn't have a standardized system for diving. The inventory of diving equipment in the U.S. Navy was a hodgepodge of various helmets, suits, pumps, and hoses by several manufacturers. Often as not pieces would not work together, making even simple assignments difficult. In 1912 U.S. Navy gunner G. D. Stillson submitted a report criticizing the way the Navy conducted its diving program. The Navy agreed and a group was formed in 1914 to standardize equipment and procedures. The original concept drawing is shown above. The Spitcock and Exhaust Valve are on the same side. The breastplate resembles a Commercial breastplate in the shape of the collar strap. In the 1916 U.S. Navy Diving Manual the Mark V Helmet first appears in its adopted form. The breastplate shape is unique to the Mark V being narrow across the shoulders and with a deep drop front and back. Some features remained from the concept helmet above with the exhaust valve on the right, a hinged front door, and air and communications elbows. The spitcock was moved to the left of the door, and guards specific to the Mark V were added.
All U.S. Navy Mark V helmets conform to a standard set of plans issued by the Bureau of Ships. Helmet shell, breastplate, all fittings and attachments are designed so regardless of the manufacturer all equipment would be compatible. Some small variances do occur between manufacturers but do not effect interchangeability.
Typical features of the Mark V Helmet are as follows:
Click on the picture to enlarge. Use your back button to return.
Click on the picture to enlarge. Use your back button to return.
1. The helmet shell tapers to the neck ring.
(Note: This rule is not hard and fast as some Mark V helmets were produced with
a "bubble shell". Do not discount the authenticity of a helmet on this point
alone.)
2. The front door is hinged and closure is with a toggle bolt. The hinge has a
removable pin to remove the door, or attach a welding shield.
3. The Mark V helmet is fitted with round side windows and an oval top window.
4. The helmet has a air inlet elbow with a separate non return valve. Both the
air and communications elbows are one piece castings, riveted and soldered in place with
backing washers inside of the helmet. You normally cannot see the air inlet
backing washer due to the ductwork inside the helmet.
5. The helmet has a communications elbow fitted to accept a standard U.S. Navy
Communications/Lifeline (1.715-11 thread).
6. The helmet is fitted with a telephone cup and transceiver. The telephone cup has
a shape specific to the Mark V with a bump out pointed towards the top center of
the shell. The placement of the telephone cup is symmetrical between the top,
left side window, and front door.
7. The Mark V helmet has a double spring adjustable exhaust valve with a exhaust
tube extending under and behind the right side window. The exhaust body (known
as a banana exhaust because of the shape) is a one piece brass casting its
entire length. The exhaust can be activated from the inside by the diver with
his chin. The bulb on the end of the exhaust is drilled with vent holes. The
pattern of these holes varies some by manufacturer.
8. The helmet is fitted with a ball lever lock assembly. The ball lever pivots
down from the top into a lockstop on the breastplate neck ring. The lock is
closed with a latch which is secured with a cotter pin on a chain. Some Schrader
helmets were fitted with a latch made from a piece of flat sheet stock. The
lockstop was also slightly different from USN specifications.
9. The Mark V Breastplate has a unique shape. It is narrow across the shoulders,
and deep on the chest and back. The front and back are nearly symmetrical.
10. The top and breastplate are joined by interrupted thread neck rings. The
shell makes a 1/8 turn clockwise to seal the connection.
11. The Mark V Helmet uses its own style wingnuts. The four wingnuts at the
brail joints are flanged.
12. The Mark V helmet is fitted with 2 loops on the front of the breastplate.
13. Most war years Mark V Helmets used a exhaust valve made by the Batteryless
Telephone Equipment Company. BTE will be stamped on the flat area of the
exhaust handle (star wheel). Later DESCO helmets uses our own 4 point exhaust handle which is
rounder than the BTE.
14. A Mark V has a standard finish of tin plating (silver color) specified by
BuShips . Many Mark V helmets have been polished by the owners or specially
ordered as polished from the factory.