Clunky engine noise on 737 ??
Whilst waiting on the spectators balcony at LPMA recently, I watched an Easyjet 737 arrive. As the engines spun down I could hear this god awful clunk with each revolution of the starboard engine. The ground crew didn't seem concerned, neither did the captain when he did a walkaround and gave the fan a spin with his hand (and the clunk was there as he did it).
I've never heard this before.
Any ideas on what it might be, and why nobody seemed concerned ?