FOD'd Conway

[Za150]

Came across a couple of photos while sorting out my computer, i think this Conway has seen better days.....





Might have posted there before, but thet are circa 1980ish

[Mayfly]

Ouch!!!!

not seen them before - any idea what caused it?

[Jigsaw]

Ouch!!!!

not seen them before - any idea what caused it?

FOD

Seriously though, I would like to know too

[RLN]

Bugger

[Sooty655]

Hard to be sure from the fairly lo-res images, but it looks like the compressor damage is mostly on the trailing edges. This often means that something has let go within the compressor causing it to surge, The pressure ratio and failing airflow will then cause a lot of the bits to cough out of the front. The rest of the debris is carried through the combustion system, cooked, and splattered through the turbines as seen in the second picture.

[RLN]

As you say, hard to see. I guess jet engines don't have surge protection as such. Please correct me, as I'm interested, 'cos our machines have Blow-offs that open at certain rpm etc.They also open for emergency conditions, depending on the pressure diffs.

[Dan4th]

I love it when you talk dirty, Martyn.....

D.

[RLN]

Marvellous. I try to be serious, and then someone reminds me not to be such a prat. Great Thanks D. Talk dirty



Sooty et al. It was a serious question.

[Dan4th]

RLN, that was the best laff I've had all day!

Hope you didn't mind, but it was just too
good to pass up!

I am REALLY looking forward to getting
plastered in your august presence, sir!

Yours, etc.,

Dan4th

[RLN]

Sir, I cannot wait for you to set foot on these shores. I'm sure we'll drink some establishment dry.

[Dan4th]

Apprehended, more like it......

D.

[RLN]

That's OK. All you have to do is demand to speak to the American Embassy, and the local plod will let us go.

[Dan4th]

Sounds like a plan to ME!

D.

[Sooty655]

As you say, hard to see. I guess jet engines don't have surge protection as such. Please correct me, as I'm interested, 'cos our machines have Blow-offs that open at certain rpm etc.They also open for emergency conditions, depending on the pressure diffs.

Some jet engines do have surge protection for expected surges, such as during acceleration from start up to normal running speeds. For example, the Avon had/has blow off valves at two compressor stages which are open at low speed and close as the speed increases. Variable inlet guide vanes (and sometimes several variable stator stages) are also used for the same purpose. Multi-shaft engines (Olympus, Conway, etc) generally require less provision for start-up surges.

However, if a compressor stage suffers a mechanical failure, you have a situation where a pressure ratio has already been generated which now can't be sustained. In that case, the compressor will surge (and cough some or all of the bits out of the front) whatever protection is fitted.

[RLN]

Thanks Sooty. Much the same as our Gas Turbines.

[Mackrick]

Hail storms don't do them much good either .....

[Sooty655]

Hail storms don't do them much good either .....

... and Rolls Royce went bust in 1970 trying to make Hyfil fan blades on the RB211 stand up to the rain.

[Jigsaw]

[Za150]

all i know it was some sort of FOD that caused the damage, as the photos are part of a FOD presentation that was pasted to me.

I dare say that it was a smaill piece of FOD that caused that engine to sugre and spit its guts out both ends!!

[Saracenman]

let's just hope it was a CAT!

sm

[Jigsaw]

let's just hope it was a CAT!

sm

What purrs and travels at 150mph?

[Checkflaps]

let's just hope it was a CAT!

sm

What purrs and travels at 150mph?

A cat being sucked into a jet engine. Oh come on - it had to be done.

G