Two PFRF tests resulted in damage to the booster engine thrust chambers, necessitating their replacement, after which 10A was taken down from the pad for a complete overhaul following the findings from 6A's flight.
32.
The E-D 10k nozzle had a chamber pressure of 15.5 bar ( 1.55 MPa ) delivering 10, 000 lbf ( 44.5 kN ), a cooled-thrust chamber and was tested in an altitude simulation facility.
33.
Officials said the engine performed well, though some erosion, in the form of pinholes, was noticed on an inside wall of a thrust chamber, a structure that replaces the bell-shaped nozzles of conventional rocket engines.
34.
After a delay of 1, 3, or 8 seconds, during which time fuel was circulated through the thrust chamber to condition the engine for start, the start tank discharge valve was opened to initiate turbine spin.
35.
The chamber was bell-shaped with a 27.5 : 1 expansion area ratio for efficient operation at altitude, and was manifold, located midway between the thrust chamber throat and the exit, at a pressure of more than.
36.
The major components of a cryogenic rocket engine are the combustion chamber ( thrust chamber ), pyrotechnic initiator, fuel injector, fuel cryopumps, oxidizer cryopumps, gas turbine, cryo valves, regulators, the fuel tanks, and rocket engine nozzle.
37.
While N-18 flew successfully from the Cape on March 21, N-21 suffered another second stage failure after having been delayed several weeks due to another episode of the first stage thrust chambers breaking off prior to launch.
38.
The installed Pintle Injector, unique to TRW designed liquid propulsion systems, provides improved reliability and less costly method of fuel-oxidizer impingement in the thrust chamber than conventional coaxial distributed-element injectors typically used on liquid bipropellant rocket engines.
39.
Some expander cycle engines may use a gas generator of some kind to start the turbine and run the engine until the heat input from the thrust chamber and nozzle skirt increases as the chamber pressure builds up.
40.
Soviet engineering and manufacturing processes never satisfactorily resolved combustion instability in larger RP-1 / LOX engines, so the RD-180 engine used to power the Zenit family still used four smaller thrust chambers fed by a common engine mechanism.
