EasyJet Flight: Rattling Gas Turbine (V2500)

[bill nye scienceguy!]

I was on an easyjet flight this morning and noticed a distinct and pronounced rattling, clicking noise coming from one of the engines. Not being a very good flier at the best of times (despite working in the aerospace sector) I was pretty worried. When the engines spooled up I was also sure I could feel a throbbing kind of vibration I wouldn't normally expect.

Clearly the engine didn't fail as I'm writing this now, but what could be the cause of the noise? Is there a genuine problem with the engine or is it a normal phenomenon I haven't encountered before? The airframe was an a320 and the engine I'm pretty sure was a v2500.

 

[xxChrisxx]

If it was anything catastrophic, the engine would have just torn itsself to bits. The words rattle, vibration and high speed rotation just don't go together.

The rattle and vibration could have been anything and your mind was playing tricks on you. It's the tendency of people who aren't good fliers to think the worst about a situation.

 

[JaredJames]

Are you sure the noise came from the engine itself?

There are a lot of things that could cause a rattling noise.

EDIT: Beaten by Chris

 

[c.smith10]

was the engine running or just rotating due to wind acting on the fan blades?

 

[JaredJames]

was the engine running or just rotating due to wind acting on the fan blades?

Well given the flight took place, I'd hope it was running.

 

[c.smith10]

You say in your original post that the rattling was heard before the engine spooled up which is why i asked if the engine was running or not, if was running I am not sure what the noise was, if it wasn't running i would have a fair idea,

 

[JaredJames]

You say in your original post that the rattling was heard before the engine spooled up which is why i asked if the engine was running or not, if was running I am not sure what the noise was, if it wasn't running i would have a fair idea,

The noise during spool up was a separate issue.

However, the rattling was during the flight.

At least that's how it reads.

 

[AlephZero]

If tha fan was being turned round slowly by the wind while you were walking up the steps to board the aircraft, a "rattling" noise is perfectly normal. The fan blades are slightly loose in the disk, and they "topple over" with a click when they pass the 12-o-clock position as they rotate.

This doesn't happen when the engine is running, because the radial accelerations on the blades are (literally) thousands of times the force of gravity and that holds the blades fixed.

Most likely the "throbbing" noise was caused by the engines not running at exactly the same speed. There is an electronic link between the two engine control systems that synchronizes the speeds to prevent this happening all the time, but it is often switched off until the engines are properly warmed up after a cold start, and also during takeoff and landing (because if one engine slows down because of some failure condition, you don't want the other engine to automatically do the same!)