Flown Space Shuttle Orbiter Aft Fuselage Gas Sampling System (OAFGSS) bottle assembly, measuring 10″ x 3.5″ x 2″, stamped on the main cylinder, "NO1 Right," and labeled, "SED331051-301, P/N 1515-3, S/N 1026, Reprocessed FLT-3." The refurbished unit now also bears a "Class III, Not for Flight" label. Includes its JSC tag and part bag.
The OAFGSS system is designed to determine if and at what levels explosive exhaust gasses were being collected in the Orbiter Aft Fuselage during ascent of the Space Shuttle. For this purpose, several gas transfer assemblies were developed and flown on the Orbiter. Each of the assemblies were programmed to sample exhaust gasses at several locations and altitudes along the Orbiter ascent trajectory. After a mission, these assemblies were downloaded and taken to a laboratory for gas analysis.
The Orbiter Aft Fuselage Gas Sampler System is comprised of two self contained subsystems, right and left. Each subsystem has three sample bottles, six pyrotechnics, and one electronics and control unit that contains a battery, a control unit, and associated hardware. Each subsystem is acoustically activated at liftoff (135 dbfor 6 seconds) and proceeds sequentially to activate the bottle fire-open pyrotechnics in bottle 1 right side (+60 seconds), bottle 2 right side (+74 seconds), and bottle 3 right side (+116 seconds). Each bottle fire-closed pyrotechnic is activated 2 seconds after the open command. The respective bottle fire-open times for the left side are +74 seconds, +82 seconds, and +104 seconds.
