Last week, I flew on a Spanair A320 (actually the newest in the fleet, EC
-IOH, delivered last May) from Munchen to Valencia, and I was sitting in row 4, just next to the RR
-engine. At take-off, the very specific roaring of the engine was very loud, until almost top of climb. Only the RR
powered A-320's (and of course A319's and A-321's) produce this particular sound, which seems to be very specific for just this type of engine, and is totally different from the sound of every other jet engine. This sound is almost like the sound of a propeller. What causes this sound? Is it the fan? It disappears when the engine power is reduced after take-off.
Thanks for your information.