Need help identifying a Limpet Mine

[ordnance]

This recent find has me stumped. It was tentatively identified as a British practice limpet by another member here but I can't find any information on it. It has a small paper label attached indicating it came from the Naval Ordnance facility at Hawthorne, Nevada and there are no broad arrow marking or anything else suggesting British origin.

The magnets on the base are wooden replicas and there are no internal parts. Any help is appreciated.

 

[sgdbdr]

The base part is the U.S. Demolition charge, underwater Mark 26 Mod 0, but I have no idea about the upper part.

 

[Eggburt1969]

The top part looks like a hydrostatic extender used on US naval mines. A hydrostatic extender is used to detonatively arm the mine, i.e. move the detonator into the booster when a certain hydrostatic pressure is reached.

A similar looking model extender (MK 14 MOD 0) can be seen in the diagram below of the MK 27 MOD 0 influence mine. The diagram was taken from the web version of the 1994 USN Bomb Disposal School publication 'Mine Disposal Handbook - Part 2 - US Underwater Ordnance (1944)'.



The website version of the USN publication is available at the link below.

Mine Disposal Handbook

maritime.org

The make markings on the black bit of the upper part seems to be A.W. INC. The mark (MK) and model (MOD) of the extender (if it is one) have been fiddled with, so it's hard to tell what it is? It may be either EX. MK. 16-0, or EX. MK. 14-0. The serial number on the black bit of the upper part seems to be empty.

 

[microplastic]

 

[ordnance]

Great info. The markings actually show up better with the flash of the photo than in person. So it's two different items that don't belong together. Is the U.S. Mk26 limpet a direct copy of the British MkIII as it appears? Does anyone have good photos of the American Mk26 version? Thanks to all for the identification.

 

[weberoed]

The base part is the U.S. Demolition charge, underwater Mark 26 Mod 0, but I have no idea about the upper part.

I have a reasonable library on US limpets, but nothing on a MK26. Fo you have anything on it? Thanks

 

[MINENAZ16]

I have a reasonable library on US limpets, but nothing on a MK26. Fo you have anything on it? Thanks

Mk26 is mentioned in : [S-2-2-2]

 

[Lefa.]

Very interesting.. and confusing.
It seems to me that the body of the mk26 is just used as adhesion method for the upper pressure device, it is empty and holed on the side, the device is connected by those odd long bolts, nothing speaks waterproof down there. It might be for above water use. It might not be a limpet mine altough made with a limpet case. I'll have a look at the upper device.

 

[sgdbdr]

Mk26 is mentioned in : [S-2-2-2]

It is also mentioned once in OP 2212 "Demolition materials"