tdtracer
..... Normal vibration would then allow the T/R to move slightly, the prox sensor would indicate not-stowed and the cycle would repeat. On one of those cycles, when auto-restow opened the isolation valve - for reasons that were never firmly established - the directional control valve changed state to deploy... Whoops
Yes and the critical valve initially could not be found even among the parts being flogged off at the local flea markets. Later I heard that it was found after having been rebuilt in some native's hut.
Your comment about vibration reminded me of the reverser deployment that turned the aircraft over 360 degrees and was only discovered in the data days later with three of us reviewing the DFDR I still remember the remark by one of us as "holy-****" when the roll passed through 180 degrees Again flickering lights. When we tried to duplicate it it wouldn't deploy on the ground during runups (fail safes worked) until somebody gave a rap to the side of the engine with his hand and it deployed (specific vibration floated a fail-safe spring)
lessons learned which I will never forget !!! but now the regs call for three levels of safety .... but it's memories of what we all screwed up that I shall never forget