There is confusion here between the datum/low switch which is:
1. Wire locked
2. Increases temperature and therefore thrust in dry power
3. Only very rarely used as the engineers/sooties get grumpy
4. Don't know if it gives extra on top of combat pwr (I spy a good staneval question!)??
Combat power is:
1. A detent post max reheat
2. Gives a bit more thrust
2. Can be used whenever you like (5 mins yadayadayada)
3. Rarely needed as the Tornado has so much thrust and great aerodynamics.
Hope that helps.
Please note that one of the above statements is a lie. If you can't work out which one, you should log off PPRuNe Mil forum immediately. zero/zero I fear this may apply to you!
So the Datum/low switch is similar to the Vmax switch which is also wired guarded. The exception is that Vmax only comes into effect when in Max AB and supersonic.
Judging by its name, Combat power I guess would only be needed when evading defences and during heavy take-offs, so I assume the restrictions are ok.
I wonder, has the triple spool layout of the RB199 been a factor in allowing the aircraft to have a Combat setting?
BTW Combat power point 3 is the most
accurate statement
