A German Type UB II submarine, UB-29 had a displacement of 265 tonnes (261 long tons) when at the surface and 291 tonnes (286 long tons) while submerged. She had a total length of 36.13m (118ft 6in), a beam of 4.36m (14ft 4in), and a draught of 3.66m (12ft). The submarine was powered by two Benz six-cylinder diesel engines producing a total 267 metric horsepower (263shp; 196kW), two Siemens-Schuckert electric motors producing 280 metric horsepower (210kW; 280shp), and one propeller shaft. She was capable of operating at depths of up to 50 metres (160ft).