A320 slow spool-up
Good morning,
I had a strage engine behaviour the other day, and i can't find reference in any manual. It's not the first time it happens, but i cannot replicate it if i wanted
Start situation
-CFM engines
-8000ft SPEED/ALT/NAV
-IAS 255kts approx, with spd selected 250
-N1 approx 40 to 50%
I have been cleared to FL 200 so, selected and pull
-FMA THR CLB/OP CLB/NAV
Still the engine stayed at the same N1 (i am not sure, but i believe the actually even spooled down a bit)
After few -very long- seconds, engines spooled up to CLB THR and everything started working normally again
I am aware of the FCB9 "THRUST ACCELERATION IN A/THR MODES", but this is not the case (as the engine where no spooling up at all)
I looked for references in the FCOM, but i can't find any to explain this behaviour
Any thoughts?
Thanks in advance