Another Acceleration Hangup on a B777.
This may be a blessing in disguise!!
Remarkable and let's hope 'they' can identify the cause. Presumably the fuel system and FADEC is standard to whatever engine leaving only the engine driven High Pressure fuel pump/s as a variation.
What doesn't seem to have been covered so far on this thread are the ACUs - Acceleration Control Units. Are these part of the FADEC and hence computer controlled and are there variable compressor guide vanes and compressor bleeds in the engines also being controlled by the ACUs?
Remember the RR Avons and the gubbonry necessary to have them accelerate cleanly what with guide vanes and bleed valves inter related. Was it 18 or 28 seconds from idle to max following a throttle slam? Once had one of these in an F-86 Sabre maladjusted under investigation hicoughing around a circuit with some of the surges putting out the fires. Saved from deadsticking with easy HOT relights.
For the uninitiated a HOT Relight is defined as one that can often reliably be achieved within 10 seconds of a flame out.