Those wonderful turbine reversers on the -100 were operated by push-pull cables. A reverser drive unit was mounted on the engine gearbox. When reverse was selected it actually clutched into the engine gearbox and drove a ball-nut jackscrew. This pushed back four thick cables which were enclosed in sleeves. These were routed aft and spread to four points on the periphery of the reverser sleeve and shoved it aft. Linkages picked up the blocker doors.
Push-pull cables that are routed around a hot tailpipe tend to seize as did the tracks for the sleeve and the linkages. However the jackscrew on the engine gearbox did have the considerable power of a JT9D to drive it. On many occasions, troubleshooting a reverser failure the techies would open the lower cowling doors and be greeted with hunks of jackscrew casing and a shower of ball bearings. The jackscrew assembly had literally burst with the effort.
Locking the turbine reverser out required the sleeve be pushed forward. For this, the trusty beltloaders used for loose-baggage loading were a God-send. The thick rubber bumper at the top of the belt prevented damaging the sleeve and the engine on the unit gave the push. Much better than beating on it with heavy wooden balks although we did that too on occasion.
Eventually Boeing or maybe Pratt gave up on the turbine reverser. Then I went to Palmdale for L-1011 school and found Lockheed insisted that their "Hot Stream Spoiler" was necessary. They used two jackscrews back on the tailpipe to push the sleeve back and they were driven by very high rev flex shafts. The flex shafts and jackscrews did not like being in the company of a hot tailpipe either. They often failed and eventually, Lockheed gave up on them too. Never had anything to do with the DC-10 and I wonder if they went down the same path?
Last edited by tonytales; 18th Apr 2018 at 07:57.
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