Thunderball - classic CosMoS SDV in classic Bond movie

The orange midget sub in Thunderball is actually a real SDV (Swimmer Delivery Vehicle). I recently watched back-to-back Bond classics on a transatlantic flight which reminded me. The horrific jetlag was well worth it. The underwater battle scenes in Thunderball are timeless, and are relevant to SDV history in a couple of ways.
James Bond SDV midget Submarine from Thunderball made by CosMoS
SPOILER ALERT: In the movie, the villain Largos manages to steal an armed Vulcan V-Bomber and crash land it in a place where only a midget sub can get to its nuclear payload. He steals the nuclear bombs and holds the world to random. Bond catches up with him and an epic underwater battle ensues. The battle itself is completely unrealistic, and the vehicles shown are film props and civilian toys. But there is one SDV is used to transport the nuclear bombs between the Vulcan and a secret underwater cave, and then to Largo’s clever hydrofoil yacht.

The SDV is not immediately recognizable. The manta ray cowling is just for the film, but the canopy and rear fuselage give it away. It is an Italian made Cos.Mo.S Seahorse-II two-man SDV.
James Bond SDV midget Submarine from Thunderball made by CosMoS

THE book on Special Forces subs Covert Shores 2nd Edition. A world history of naval Special Forces, their missions and their specialist vehicles. SEALs, SBS, COMSUBIN, Sh-13, Spetsnaz, Kampfschwimmers, Commando Hubert, 4RR and many more.
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UPDATE: new photos
Since publishing the original post, a good friend has provided these cool behind-the-scenes photos of the modified Seahorse-II. He confirmed that my identification was correct, although I got the 'Flipper' sub slightly wrong (see bottom of page). Many thanks!

1. Cos.Mo.S Seahorse-II SDV in US Navy service
The Seahorse-II was operated by the US Navy's elite UDT (Underwater Demolition Team) frogmen and SEALs from the late 1950s through to the late 1960s. At the time it was relatively secret, and there are credible rumors that some related craft were supplied by the CIA to anti-Castro Cuban forces. Initially they were called SPUs (Swimmer Propulsion Unit) but by the time Thunderball was released the term ‘SDV’ had been coined and was in use by UDT/SEALs and the British SBS.
James Bond SDV midget Submarine from Thunderball made by CosMoS
From SEAL TWO . ORG ► great website with vintage photos andinfo of SEALs / UDT

Not all of the Seahorse-IIs had canopies and there were many sub-versions and modifications. The canopy shown in Thunderball is a standard factory supplied type which was fitted to at least one USN SDV. A Flickr stream with great photos of a surviving US Navy Seahorse-II with the same canopy type: Marty4650's Flickr stream.

James Bond SDV midget Submarine from Thunderball made by CosMoS
Note that the canopy has been fixed halfway back (it ordinarily hinged sideways) with the Perspex removed so that the rear passenger can get in and out safely.
James Bond SDV midget Submarine from Thunderball made by CosMoS

2. The Thunderball effect
Author Ian Fleming was a real-life Naval Intelligence Officer in WW2. As part of an inner circle of Allied intelligence staff and spies Fleming undoubtedly knew a great deal about the many cunning gadgets used by SOE (Secret Operations Executive). This world overlapped with Special Forces (e.g. SBS, RMBPD, COPP, Charioteers) and it seems highly likely that Fleming knew of the various midget subs and wet subs used by SOE and other units within Combined Operations, probably first hand.

But the underwater battle in Thunderball is completely unrealistic. Quite aside from the fact that masses of frogmen do not fight underwater (it has never happened, read the Covert Shores book), but it had to take place in daylight for filming reasons. The breathing apparatus used was open-circuit air SCUBA kit which while popular with some units at the time for safety reasons (notably the US Navy’s UDT), was not suitable for covert missions due to the bubbles it releases. The knife fighting was also unrealistic (try cutting a hose with a knife) and the spear guns are something which has been tried and abandoned several times.

Don’t get me wrong, it is a great fight scene, but it is nothing like what I’ve learnt researching Special Forces combat swimming. HOWEVER, non-divers of the time did not know (or want to know) that. I have been told in interviews with retired Special Forces swimmers that the lack of realism of Thunderball was completely lost on a segment of senior officers within the Armed Forces. Suddenly Special Forces were expected to conduct wholly unrealistic operations and the science of combat swimming was rendered easy and straightforward. And that was a problem for Special Forces officers who found themselves having to say "no" a lot.

A related 'fake' TV midget submarine
The 1960s US TV show Flipper starred a dolphin, but it also involved the original Cos.Mo.S Seahorse-I (not Seahorse-II) modified with electric propulsoion (the original configuration was a combustion engine!) and with the canopy covered to look like a dry midget submarine.
James Bond SDV midget Submarine from Thunderball made by CosMoS
Photo from Coral Key Park
More photos on Flickr

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