Protei-5 Russian diver propulsion vehicle
The Protei-5 (Протей-5) is a small Russian one-man diver propulsion vehicle often used by Russian commando frogmen. It is battery electric powered, using six non-sealed lead–acid batteries. It clips on under the diver with a clip over each shoulder and one up between his legs. Its casing is aluminium. It was intended to be clipped onto the outside of a submarine; near the operation site the frogmen would airlock out underwater and unhitch their Protei 5's and ride them to the operation site. It seems to have been intended to be ridden fast and far rather than for complicated maneuvering.
The Russian for "diver-carrying vehicle" is буксировщик buksirovshchik = "tugger".
The rod sticking out of the front end was meant to carry a lamp.
The lever on the left bow is the motor's on/off switch. There is no speed control.
The frogman steers with the diving fins on his feet.
Overall size: 2 feet 2 inches (66 centimetres) wide, 2 feet 3 inches (69 centimetres) high, 5 feet 9 inches (1.75 m) long.
Size of hull: 2 feet 2 inches (66 centimetres) wide, 1 feet 3 inches (38 centimetres) high, 4 feet 9 inches (1.45 m) long.
A frogman with an IDA71 rebreather riding a Protei-7 could pass through a hole 3 feet (0.91 m) square.
Only two Protei-5 have found their way out of the ex-USSR, as far as is known:
- One is in upstate New York, USA; currently (as of March 2008) it is not working because the batteries that came with it are too big for the Protei-5's battery compartment.
- One is fully operational in New Jersey, USA; it  was made in 1970, and its motor is noisy and in a secret attack or reconnaissance operation would likely be easily heard by hydrophones. This example was imported by Mr. David Sutton along with some 150 IDA-59, IDA-64, IDA-71, and AKA-60 rebreathers, all ex-Soviet military combat swimmers systems.
There have been similar designs made in Russia, including a model called Proton.
- Diver Dave's Site, going by information received, said that its batteries were silver–zinc batteries, but on examination they proved to be lead–acid batteries.
- ref YouTube video linked below
- Diver Dave's Site 17 images and a longer description of a Protei-5
- article "Riding on Proton" by Afonchenko (in Russian, with 6 images, about diving with a similar craft called a Proton)
- http://babelfish.altavista.com/babelfish Auto-translator, including from Russian to English
- YouTube videos:
-  (4 minutes 58 seconds long): Protei-5 pool tests; the front handlebar and the repaint were added after it left Russia.
-  (4 minutes 40 seconds long): How this Protei-5 was renovated and got working
-  (5 minutes 34 seconds long): First test at Dutch Springs
-  (3 minutes 11 seconds long): Second test at Dutch Springs: Protei 5 proved faster than a standard Dacor scooter; Protei 5 estimated duration on a batteryful 3 hours 40 minutes
-  (4 minutes 44 seconds long): Underwater speed and battery-endurance contest between a Protei-5 and a Farallon MK-7 scooter