Company
Information
as of 12/21/11
Current DESCO, CBE, & Viking price lists.
Current
Products
as of 01/27/12
Product
Support
Technical Information
Product warnings and
cautionary notes
Historical Information
How DESCO started
Those who built DESCO
General product history
Photo Galleries
DESCO company
photos and photos
from our archives
Commercial Diving Photos supplied by customers
Classic equipment &
hobby diving photos
Photos of helmets from
other manufacturers
Photos of equipment on display in museums and private collections
Photos from some of
our repair projects
DESCO U.S. Navy Helium Diving Helmet
Cat. No. 29019
Single Exhaust Helium Helmet
Double Exhaust Helium Helmet
This is the standard U.S. Navy Helium/Oxygen Mixed Gas Helmet based on the standard Mark V Helmet. The main feature of this helmet is the canister mounted on the rear of the helmet and a venturi system allowing for recirculation of breathing gas to conserve Helium. The canister was filled with a scrubbing agent to remove Carbon Dioxide from the breathing mix.
The breastplate is the same as a normal Mark V except the lock assembly is located in front in place of the spitcock. All other parts are the same as a standard Mark V except for the omission of the spitcock valve, and the addition of a extra communications elbow which the Navy used to connect electrically heated underwear to a power source.
The canister can be removed and with the canister elbows capped the helmet can function as a normal Mark V. Standard finish is Tin plate but the helmet is also available polished. Shipping weight with canister approximately 93 lbs.
The U.S. Navy Mark V Helium Helmet is available in two versions. DESCO can produce either style of this helmet.
Single exhaust Valve (The Early Version)
The early version has the exhaust tube extending to the back of the helmet.
Double Exhaust Valve (The Later Version)
The newer style incorporates a Double Exhaust Valve on top of the helmet. It was
found that when salt water leaked back through the exhaust valve and got into
the scrubbing agent Chlorine gas formed. This would result in serious injury or
death to the diver. A secondary exhaust valve was fitted to stop leak back. This
change was made in the early 1950's. Also added is a top lifting ring due to the
extra weight of this rig. Original single exhaust Helium helmets did not have a
lifting eye (as shown in the drawings below). We offer the lifting eye as an
option on both styles of USN Helium Helmets.
A Special Helium Helmet
HDS Limited Edition DESCO U.S. Navy Mark V Helium Helmets
DESCO was commissioned by the Historical Diving Society USA to produce 26 U.S. Navy Mark V Helium Helmets to commemorate the successful salvage of the USS Squalus. This operation was the first practical use of Helium Oxygen diving, and was the culmination of years of research by the US Navy and civilian experimenters. The 26 helmets also commemorate the 24 crewmen and 2 civilians who were lost when USS Squalus sank during a training dive May 23, 1939.
These helmets are the third commemorative series produced for the HDS. Each helmet in the issue will bear a special USS Squalus Commemoration tag, and will be numbered 1-26 to 26-26.
All twenty six helmets were sold to HDS members. A 27th helmet resides with DESCO as the prototype. It was built for our collection from parts deemed unusable for the production helmets. It has the prototype Silver tag bearing the serial number 00/26. We are dedicating this helmet to the divers, tenders, ships crews, and engineers who made the rescue and recovery possible.
