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Papers by John Albright

Research paper thumbnail of Performance of the Space Shuttle Orbiter RCS primary thruster when equipped with direct acting valves

30th Joint Propulsion Conference and Exhibit, 1994

Research paper thumbnail of Lessons Learned from the Design, Certification, and Operation of the Space Shuttle Integrated Main Propulsion System (IMPS)

47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 2011

The Space Shuttle Integrated Main Propulsion System (IMPS) consists of the External Tank (ET), Or... more The Space Shuttle Integrated Main Propulsion System (IMPS) consists of the External Tank (ET), Orbiter Main Propulsion System (MPS), and Space Shuttle Main Engines (SSMEs). The IMPS is tasked with the storage, conditioning, distribution, and combustion of cryogenic liquid hydrogen (LH2) and liquid oxygen (LO2) propellants to provide first and second stage thrust for achieving orbital velocity. The design, certification, and operation of the associated IMPS hardware have produced many lessons learned over the course of the Space Shuttle Program (SSP). A subset of these items will be discussed in this paper for consideration when designing, building, and operating future spacecraft propulsion systems. This paper will focus on lessons learned related to Orbiter MPS and is the first of a planned series to address the subject matter.

Research paper thumbnail of Development and Implementation of Electromechanical Actuators for the X-38 Atmospheric Test Vehicles

AIAA Atmospheric Flight Mechanics Conference and Exhibit, 2008

Research paper thumbnail of Lessons Learned from the Space Shuttle Engine Hydrogen Flow Control Valve Poppet Breakage

47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 2011

During ascent of OV-105 during the STS-126 mission, a Main Propulsion System (MPS) engine hydroge... more During ascent of OV-105 during the STS-126 mission, a Main Propulsion System (MPS) engine hydrogen flow control valve (FCV) appeared to transition from the low towards the high flow position without being commanded. The other two valves compensated for the additional flow as expected, and there was no impact to the mission. After landing, an x-ray on the vehicle indicated the cause was a broken poppet. The valve was removed from the system and sent to the vendor for teardown and evaluation. Both the vehicle pressurization system and the valve piece parts were inspected for clues as to the breakage, but no out of print condition, material non-conformance, or evidence of particle impact were found. Structural breakage of metal components is very rare in the MPS, especially during flight. A high speed particle impact causing the poppet to liberate a fragment had already been ruled out, so it was initially believed that the cause would be a defect in the poppet's material (440A steel) or an irregularity in its manufacturing. However, the poppet flange sees no impact load or mechanical stress in service since the high flow and low flow stops are located elsewhere along the poppet and seal. Three FCVs, one per engine, provide Gaseous Hydrogen (GH2) pressurant to the External Tank (ET) hydrogen tank in flight in order to maintain tank pressure as the liquid is consumed. Each valve is commanded on or off by its corresponding ullage pressure signal conditioner. The inlet to each FCV is 3,300 psi hydrogen gas supplied by its corresponding engine. The three outlet flows join via a manifold and are routed to the top of the ET liquid hydrogen (LH2) tank.

Research paper thumbnail of Lessons learned during fabrication of a PTFE seal in a redesigned PRCS thruster valve

36th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 2000

ABSTRACT

Research paper thumbnail of Factors contributing to pilot valve fuel seal extrusion in orbiter PRCS thrusters

36th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 2000

Research paper thumbnail of Lessons Learned During Redesign of Shuttle Reaction Control Thruster Pilot Seat Assembly

Journal of Spacecraft and Rockets, 2005

ABSTRACT

Research paper thumbnail of Performance of the Space Shuttle Orbiter RCS primary thruster when equipped with direct acting valves

30th Joint Propulsion Conference and Exhibit, 1994

Research paper thumbnail of Lessons Learned from the Design, Certification, and Operation of the Space Shuttle Integrated Main Propulsion System (IMPS)

47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 2011

The Space Shuttle Integrated Main Propulsion System (IMPS) consists of the External Tank (ET), Or... more The Space Shuttle Integrated Main Propulsion System (IMPS) consists of the External Tank (ET), Orbiter Main Propulsion System (MPS), and Space Shuttle Main Engines (SSMEs). The IMPS is tasked with the storage, conditioning, distribution, and combustion of cryogenic liquid hydrogen (LH2) and liquid oxygen (LO2) propellants to provide first and second stage thrust for achieving orbital velocity. The design, certification, and operation of the associated IMPS hardware have produced many lessons learned over the course of the Space Shuttle Program (SSP). A subset of these items will be discussed in this paper for consideration when designing, building, and operating future spacecraft propulsion systems. This paper will focus on lessons learned related to Orbiter MPS and is the first of a planned series to address the subject matter.

Research paper thumbnail of Development and Implementation of Electromechanical Actuators for the X-38 Atmospheric Test Vehicles

AIAA Atmospheric Flight Mechanics Conference and Exhibit, 2008

Research paper thumbnail of Lessons Learned from the Space Shuttle Engine Hydrogen Flow Control Valve Poppet Breakage

47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 2011

During ascent of OV-105 during the STS-126 mission, a Main Propulsion System (MPS) engine hydroge... more During ascent of OV-105 during the STS-126 mission, a Main Propulsion System (MPS) engine hydrogen flow control valve (FCV) appeared to transition from the low towards the high flow position without being commanded. The other two valves compensated for the additional flow as expected, and there was no impact to the mission. After landing, an x-ray on the vehicle indicated the cause was a broken poppet. The valve was removed from the system and sent to the vendor for teardown and evaluation. Both the vehicle pressurization system and the valve piece parts were inspected for clues as to the breakage, but no out of print condition, material non-conformance, or evidence of particle impact were found. Structural breakage of metal components is very rare in the MPS, especially during flight. A high speed particle impact causing the poppet to liberate a fragment had already been ruled out, so it was initially believed that the cause would be a defect in the poppet's material (440A steel) or an irregularity in its manufacturing. However, the poppet flange sees no impact load or mechanical stress in service since the high flow and low flow stops are located elsewhere along the poppet and seal. Three FCVs, one per engine, provide Gaseous Hydrogen (GH2) pressurant to the External Tank (ET) hydrogen tank in flight in order to maintain tank pressure as the liquid is consumed. Each valve is commanded on or off by its corresponding ullage pressure signal conditioner. The inlet to each FCV is 3,300 psi hydrogen gas supplied by its corresponding engine. The three outlet flows join via a manifold and are routed to the top of the ET liquid hydrogen (LH2) tank.

Research paper thumbnail of Lessons learned during fabrication of a PTFE seal in a redesigned PRCS thruster valve

36th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 2000

ABSTRACT

Research paper thumbnail of Factors contributing to pilot valve fuel seal extrusion in orbiter PRCS thrusters

36th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, 2000

Research paper thumbnail of Lessons Learned During Redesign of Shuttle Reaction Control Thruster Pilot Seat Assembly

Journal of Spacecraft and Rockets, 2005

ABSTRACT

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