EEC in Alt mode

[SRS]

With one EEC U/S all engines need to be selected to ALT mode. No auto- throttles, fine but why is there a HUGE weight penalty? Do the engines, which are manually set at full EPR ( P&W) produce so much less thrust?

Any answers?

Thanks.

[Piltdown Man]

I'll guess: Following an engine failure, the power setting of the functioning engine may not be correct.

PM

[de facto]

In the EEC alternate mode,the thrust schedule will provide equal or more thrust for the same lever position.
The accepted method is to reduce the performance limit weight and therefore the thrust lever position(lower N1) to avoid overshoot of the max rated thrust at a less than full forward position.(no thrust limit protection with the EEC alternate mode).
The v speeds will be increased according to a given table.