The Waco DSO,originally known as the Model 10H, was a development of the Model 10 fitted with the higher powered Hispano-Suiza. Seven are known to be extant with at least one remaining airworthy. Other variants of the Model 10H which are known to be airworthy are the Model CSO which was the Model ASO powered by a 225hp(167kW) Wright, the Model CTO Taper-Wing powered by a 225hp(167kW) Wright and the Model BSO (35 built) which was first flown in 1929 powered by a 165hp(123kW) Wright and with a maximum take-off weight of 2485lb(1128kg). A Waco CTO is shown below.

NC657N                    c/n 3166                       USA

3 seat biplane first flown in 1927

Engine: 150hp(112kW) Hispano-Suiza A                                                                                        Length: 23’6"(7.16m)                                                                                            Height: 9’2"(2.79m)Wingspan: 30’7"(9.32m)                                                                                                  No.built: 45 Range: 600miles(965km)                                                                Cruising speed: 100mph(160kmh) Empty weight: 1508lb(684kg)                                                Maximum take-off weight: 2404lb(1091kg)

A Waco DSO is illustrated below.