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Old 1st Dec 2016, 17:56
  #17 (permalink)  
Wetstart Dryrun
 
Join Date: Jun 2013
Location: Squalor
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Please excuse defective memory banks.

Maybe, Short Lift Dry was 103%, 715Deg C for 10 seconds

Possibly, Short Lift Wet was 107% 745Deg C, also for 10 seconds.

The reality was 10 gallons used on a wet take off, leaving 40 gals for recovery to VL. Sometimes the water injection would slow the engine accel, possibly giving a water stagnation at about 95%. The fix was to select water on as the motor hit full power.

You only need wet Thrust (107%) on short TO or VTO and the TGT sort of caught up later as you turned it off. Hovering for a VL was temp constrained to avoid cooking the engine. 670C dry or 695c wet. ...but not quite that simple because you were burning 400lb/min petrol and 400lbs of water in the same minute - so all a lot lighter, all a bit easier.

The equation was only spoiled by gentle yellow lights as you approached limits and more unpleasant red flashes as you porked it. Resultant hypertension would lead to a bit overc0ntrolling which increased TGT as engine bleed to the puffers put in a bit more fuel.

Only feel sorry for the poor QFI in the bargelike T4 that was nearly always water dependent as the FNG hovered over the field site. 'You blew down all the soddin tents,Sir! You had to weave to do that.'
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