These were the experimental small submarines for use with the Walter turbine power. The unacceptably high fuel consumption of the very fast Walter turbines made this impractical. These two boats were U-792 and U-793 as seen in KTB #115.

Displacement 313/343 tons
Length 124.75 feet
Beam unknown
Draft .unknown
Machinery in U-792 twin-shaft Walter geared turbine
Machinery in U-793 single-shaft Walter geared turbine
Machinery in both 8 cyl Dietz diesel/electric
Power (Walter on U-792) 5,000shp
Power (Walter on U-793) 2,500shp
Power (diesel on either) 210shp
Power (electric on either) 77shp
Speed (Walter on U-792) 26 knots
Speed (Walter on U-793) 21 knots
Speed (diesel on either) 9 knots
Speed (electric on either) 5 knots
Bunkers (AUROL for Walter drive) ..40 tons
Bunkers (diesel fuel) 17 tons
Range (on Walter drive) 80 miles @ 26 knots
Range (on diesel) 1,840 miles @ 9 knots
Range (on electric) 76 miles @ 2 knots
Tubes (fwd) two 21 inch (carried 4 torpedoes) (aft): none
Guns none
AA Guns ..none
Depth of dive unknown
Crew 12

There will be additional information on the TYPE XVIIA boats made under the sub-TYPE Wk.202