Hi,
When I read the posts above, I am confused. Both B 777 and B 737 NG are fitted with ECC, yet you get full rated thrust for B 777 and derated thrust for B 737 NG when you firewall the thrust levers (according to some posts above)?
If I am not mistaken I read a certain Airbus article (smartcockpit website) that states: pilot cannot recover TOGO. Don’t quote me because I don’t know the exact context where this note was mentioned, all I know is the subject deals with derated engine.
I don’t know the veracity of the following quote but here a link:
Assumed Temperature Thrust Reduction
A de-rate is a semi-permanent engine fix, used to reduce the maximum thrust available; for instance down to 20k from 22k on -3/700's. It is also used to equalise the thrust where B2 & C1 engines are mixed on the same airframe. When an engine is de-rated, the full (un-de-rated) thrust is no longer available because this would require changes to the EEC, HMU, fuel pump, engine ID plug and the loadable software; non of which can be done by the pilot in-flight.
A temporary form of de-rating known as a "T/O de-rate" is accessible through the FMC on TAKEOFF REF 2/2 or N1 LIMIT (NG's) but this is prohibited by some operators. The T/O de-rates (TO-1 & TO-2) can be 10 to 20%. It follows that an engine may be de-rated and also be using reduced thrust in which case you could be taking off at Full power -20% -25% = 60% of the full power of the engine - scary thought! Note that a T/O de-rate can overridden by firewalling the thrust levers
Feedback appreciated
Regards