Engine 11D68 detail Credit - © Mark Wade

Other Designations: Block DM; D-1-e. Class: Tug. Nation: Russia.

Upper stage / space tug - out of production. Launched by Proton. Also known as Block DM; article number 11S86. With guidance unit, designed for insertion of military spacecraft into geosynchronous/ medium earth orbit.

Used from 1974 to 1990. Succeeded by 11S861.

Unit Cost $: 4.000 million. Length: 7.10 m (23.20 ft). Basic Diameter: 3.70 m (12.10 ft). Span: 3.70 m (12.10 ft). Mass: 17,550 kg (38,690 lb). Main Engine: RD-58M. Main Engine: 230 kg (500 lb). Main Engine Thrust: 85.020 kN (19,113 lbf). Main Engine Propellants: Lox/Kerosene. Main Engine Propellants: 15,250 kg (33,620 lb). Main Engine Isp: 352 sec.