Title :
Hubble Space Telescope solar array change-out, mission anomalies and returned flight hardware
Author_Institution :
Lockheed Tech. Oper. Co., Greenbelt, MD, USA
fDate :
4/1/1995 12:00:00 AM
Abstract :
During the successful First Servicing Mission on the Hubble Space Telescope the two solar arrays were replaced with new and improved solar arrays. An electrical short and four solar array mechanical system anomalies occurred: (1) the upper outer bistem on the +V2 wing had developed kinks and then failed to retract; (2) additional friction between the solar array latch fitting and the aft latch berthing microswitch guard probably caused the failure of the primary deployment mechanism to deploy the solar array wings; (3) the secondary deployment mechanism retract limit microswitch activation is believed to be a result of the dynamic motion of the wings during the retraction event. Successful retraction took place after five attempts; and (4) additional torques induced during extra vehicular activity, flight support system and orbiter activities caused the wings to move from the latching destination. The physical appearance and durability of the materials on the solar array and the physical position of hardware indicators were investigated at Kennedy Space Center after the flight servicing mission. Evidence of micrometeoroid damage and the darkened silicone coatings were apparent. Isolation and continuity tests confirmed the location of shorts which occurred during the First Servicing Mission
Keywords :
astronomical telescopes; failure (mechanical); failure analysis; maintenance engineering; mechanical testing; photovoltaic power systems; short-circuit currents; solar cell arrays; space vehicle power plants; First Servicing Mission; Hubble Space Telescope solar array; Kennedy Space Center; darkened silicone coatings; durability; dynamic motion; electrical short; failure; flight servicing mission; flight support system; friction; latch fitting; latching destination; micrometeoroid damage; mission anomalies; primary deployment mechanism; retract limit microswitch; returned flight hardware; secondary deployment mechanism; solar array wings; torques; Aerospace materials; Coatings; Friction; Hardware; Mechanical systems; Microswitches; Space missions; Telescopes; Testing; Vehicle dynamics;
Journal_Title :
Aerospace and Electronic Systems Magazine, IEEE