Acoustic Resonance on a321's ?

[7gcbc]

Only ever noticed this on the 321's as pax, never heard it on the 74,77, or 73, however the last two/three flights as a pax on the 321's out of Eire I have definitely experienced resonance at low/sub/taxi power, infact it became uncomfortable after a minute or so, so much infact I was glad of the spool up to the TO run.

Is there a known rpm range to avoid for the powerplants on a321's ?

[barit1]

Which powerplant is involved - V2500 or CFM56-5? It sounds like a combustor resonance a la RB211.

[7gcbc]

Hi Barit1,

CFM56-5B3's the type I was on was badged a 321 although they also have the 5B4's on their 320's.