CFM Engine Blade Sound
 

Hi all,

Just a question out of curiousity here. On my company's (Orange and White planes) A320's the engines clank like crazy in high winds when shut down an parked. I know this is because there is a small amount of lateral play allowed between each LP Turbine blade. However on the competitor's (Blue and Yellow planes) 737-800's parked next door in those same high winds don't make nearly as much noise and just make a quiet wooshing sounds. They're both variations of CFM 56 engines so why the difference?

Different fans. The A320 uses the older CFM56-5 which has still 38 (or was it 36?) fan blades while the 737 uses the newer CFM56-7 with only 24 widechord fan blades. The CFM56-7 apparently has "platforms" installed between the fan blades near the root that prevent the clanking sound.

Thanks for that :ok:. Curiousity always gets the better of me.