The duration of Thrust reverse deployment is indeed dependant on forward speed and power settings not any time limits. Idle TR is often used on long descending slope taxiways to save cooking the brake units. I know early Tornado had a re-ingest warning but not sure if it was continued in later life.
There should be no possibility of assymetric deployment as if the either engines buckets don't deploy within 0.25 seconds and be fully deployed within 1.25, they both cancel and illuminate a CWP warning. The system can be overidden to restore braking but obviously the Driver Airframe would then be ready and waiting for any yaw. This was especially important if the pilot had pre-selected Lift Dump before landing. This system deployed the TR and the spoilers, and also trimmed the taileron fully nose down as soon as the WOW switches made.
There used to be a problem at high speed of the venturi effect sucking the buckets off the stowed microswich which would illuminate a thrust reverse deployed warning in the cockpit; which according to one test pilot I spoke to concentrated his mind somewhat during a low and fast Terrain Following sortie. It was cured by increasing the 'throw' on the microswitch and pre loading the drive system from the TR motor to the buckets.
All the above is based on knowledge dragged from the depths of my memory and may have mellowed with time!
Last edited by country calls; 11th Aug 2009 at 12:34.
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