Space Shuttle Payload Retention Latch Actuator (PRLA)

On this page:    Front View     Back View     Socket Detail     Mission View

  • Latch for securing payloads in the payload bay until ready for release.
  • Also known as a Standard Weight Longeron Latch.
  • 3.250” diameter pin on the payload fits into a socket on the latch.
  • Motor/gear train claw opens a two-piece spherical bearing socket to release the payload.
  • Very heavy construction using Inconel for high strength and low thermal expansion.
  • Mounts on a Longeron Bridge Fitting along the payload bay edge.
  • Four latches of this type used for securing some payloads (two of this design on one side of the payload bay, mirror design on the other side). An additional Active Keel Actuator at the bottom of the payload bay completes this retention system.

110 lbs. (49 kg)

STS41-C astronauts George  Nelson, left, and James van Hoften work on the Solar Maximum Mission satellite in the Challenger payload bay on April 11, 1984. Earlier in the mission astronauts had deployed the Long Duration Exposure Facility (LDEF). The LDEF had been secured in the payload bay using four latches similar to this type of latch (shown with yellow arrow). A fifth latch on the floor of the payload bay completed the LDEF payload retention system. (NASA photo STS41C-38-1852)

 © 1998-2015 Historic Space Systems at

[Home] [Other Parts]