Company information

General Aquadyne Inc. from Santa Barbara California produced a series of helmets and masks. These days the concept is taken over by Divex from England.


The Aquadyne masks had similar features as the Kirby Morgan masks. The first one came on the market in 1974 and was called the (Dive Mask) DM-4. DM-5 followed in 1970 and DM-6 in 1975. The masks can be worn with just the spider, with a hood and the spider or in combination with a hard helmet shell. They can be used with tanks or an umbilical, as demand or free flow mask with air or mixed gas.


Photos courtesy of Kees van Hooff

The DM-5 came on the market in 1970. In this case you see a mask complete with the shell.


Above is a photo of Buzz Marcus in 1977 using a DM5 General Aquadyne band mask. At this time Buzz was involved in the Geoduck (pronounced gooeyduck) giant clam fishery in Washington State, U.S.A. The divers spent an average of 5-6 hours per day underwater using water pressure from a fire hose to jet the large clams out of the bottom Ö. They weighed up to 4 pounds each. The Divers never exceeded the 70 foot table and did in water decompression.

In addition to the Aquadyne they wore long underwear beneath dry suits with coveralls over the top. Buzz used 48 pounds of lead on a Miller belt to keep him on the bottom, and rubber boots were worn to protect his feet. Fighting the strong current was a never ending battle, and on many occasions he would have to leave the bottom to wait out the strong tidal forces aboard their 34 foot dive boat. They worked with two divers in the water and only one tender on the surface.

Buzz tallied 5,000 plus hours of bottom time over 2 Ĺ years in that fishery. Upon leaving the fishery he attended the Diverís Institute of Technology in Seattle, and went on to become a harbour diver for Crowley Maritime. After leaving Crowley due to a lack of work, Buzz returned to Mollusc harvesting in the abalone fishery in S.E. Alaska where he logged another 2000+ hours of bottom time. Buzz now lives in the dry half of Oregon State, far from the ocean but still recalls his life underwater with great fondness and pride.


The DM-6 came on the market in 1975. In this case you see a mask with spider and hood.

Special DM versions

In 1974 General Aquadyne combined the Observer II underwater television system with the DM-5 mask, thus creating the DM-5TV. Who has pictures of these masks ?



The Aquadyne Air helmet came on the market in 1969. It is a bit smaller than the Advanced helmet but has about the same features. Air supply and exhaust valve are located on the right side of the helmet. The neck lock consists of a bayonet lock and a split ring clamp.

When putting it on the divers head, first the helmet is attached to the neck ring and then the neck ring is closed. over a continuous flange around the bottom of the helmet..

The AH-2 is positively buoyant. For this reason a jockstrap has to be used. The divers head is free to turn inside the helmet. When he wants to look to the side he has to move both head and shoulders.

photos courtesy of Kees van Hooff Standaard duikploeg DTY Holland DTY.NL

Special AH-2 versions

The following versions are very interesting as well:

Who has pictures of these hats ??

AH2 TV Helmet with integrated Observer 2 television system

Photos courtesy of Kees van Hooff

Earlier style Advanced 200 Mixed Gas helmet on a breastplate

Front and rear views of the Mixed gas helmet on a commercial 12 bolt breastplate. The locking mechanism will connect the helmet to both the breastplate and the neck dam as itís a universal fitting. The rear view shows how wide the breastplate is relative to the bonnet. There are telephone binding posts and an addition Marsh Marine cable for the underwater telephone.
Side views show the air control valve and the exhaust outlet and 2 extra ports to connect the mixed gas breather unit. The brass brales on the breastplate clamp the suit to the breastplate in the same way a Standard Dress corselet does.


On the job: Salvage diver Stig Hermansson from Sweden with his General Aquadyne AH-3  

Both the AH-2 and AH-3 can be used with a commercial breastplate and a neck ring assembly

AH-3 on a commercial breastplate. This hat is brand-new. Courtesy of our Slovenian buddy Zarko.


Have a look at this well known demand helmet. The General Aquadyne DMC-7. These hats were first made in 1974 based on the DM-5 bandmask. The helmet shell was simply added to the bandmask with 12 screws and it became a "helmet" again. On more recent models the helmet shell and the mask were integrated again, creating the DMC-7 helmet.

Photos courtesy of and thanks to Kees van Hooff Standaard duikploeg DTY Holland DTY.NL

Pictures contributed by professional diver Magnus Lundbeck from Sweden. The knob on the left is to adjust the inner linear 
(neck cushion).

Professional diver Peter Smit from The Netherlands uses his DM-7 every day.

Our buddy Mick Bacon from Australia on the job in the 1970-ies with his DM-7 equipment.