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aristoclis
29th Nov 2009, 21:14
Hello everybody,
Considering engine starter cycles and limitations:
During aborted manual start, tailpipe fire and in general manually aborted start, we have to shutdown engine and perform a manual crank.
As stated in the FCOM “The start valve automatically reopens, when N2 is below 10%.” So this limitation is automatically taken care of. What about the 15 seconds limitation between two cycles? Is the time for N2 speed drop below 10% always sufficient to reengage the starter?
Thanks.

Tinwacker
30th Nov 2009, 10:45
Your time between cycles would be taken when N2 rotor is at zero, but of course if you experience a tail pipe fire then re-engage ASAP so in your case 10% N2. Time limitation of the starter during an emergency is ignored as cheaper to replace the starter than the engine.

TW

aristoclis
30th Nov 2009, 11:21
Thanks for your reply.

My opinion was that you start counting the 15 seconds as soon the start valve closes (eng master to off). Guess I am wrong?

I can understand that during a tailpipe fire priority is to crank the engine disregarding the 15 seconds limitation. But the exact same note is stated in the FCOM 3.02.70 page 7 in the ENG 1(2) START FAULT when manual start is aborted. This note makes no sense when counting 15 seconds after N2 reads zero.

Regards.

Jim Croche
2nd Dec 2009, 10:51
Aristoclis,

Get used to the Toulouse g*ts and their warped sense of logic. They're the same bunch who tell you to switch off the starter (MAN start Pb OFF) before shutting down the engine during a Manual Start if you get a problem like a Hot Start. My boss would fire me if I saved the stfrter and burned the engine and I reckon he's right! Gallic Logic, they tell me .... and they refer to Boeing as the "B company" !!

TyroPicard
4th Dec 2009, 16:26
Jim

It does seem the wrong way round - I suspect most pilots would move the Engine Master to OFF if it looked like exceeding the EGT limit, as unlike during an automatic start the hand would remain on the appropriate switch.

There may be some Gallic logic - on the CFM the FADEC will cancel a Hot Start (up to 50%N2) on its own on a Manual Start.
Do you get that excited during abnormals in the aircraft?? - and why would your boss fire you for doing it by the book and following ECAM?

jmig29
11th Dec 2009, 00:04
Something I did not understand:

You were auto starting the engine and it showed fire on the tailpipe?

Because if this is the case, you should complete the start in order to stop that fire and lower the EGT...:confused:

TyroPicard
11th Dec 2009, 09:29
jmig29
you should complete the start in order to stop that fire and lower the EGTNot true..
For a tailpipe fire FCOM calls for Eng Master OFF in all cases.

aristoclis
11th Dec 2009, 15:46
jmig29,

although I did not understand what you did not understand, subject here is not how to deal with the tailpipe fire. Procedure is clear.

Question was about the starter limitations and how to comply (if prudent) while applying the abnormal procedures (manually aborting an auto or manual start). Thanks.

jmig29
12th Dec 2009, 00:36
Ok, I get it now, thanks for clarifying.

Will try to get some supported (as in official) info.

Regards

aristoclis
25th Feb 2011, 17:15
Hi to all,

I would appreciate your opinion to the following matter:

Suppose you do a manual start. For whatever reason you have to abort the start, let's say approx. 50 seconds after MAN START pushbutton selection. Then you will perform a 30 second cranking according to procedure.
After these actions, how many cycles do you count for the starter. One or two?

Thanks.

Microburst2002
26th Feb 2011, 17:29
It is in the limitations.

for CFM engines, starter time limitation is 2 minute (open).
Pause between start attempts, 20 sec.
Don't engage starter when N2 is above 20%

But an engine tailpipe fire is not an Emergency, is it?
So no hurry. Beacon light should be ON. The engine is built to have some fire in it. turn the Master OFF, call for the QRH procedure.

aristoclis
26th Feb 2011, 18:36
Hello Microburst 2002,

Although we have IAE engines, I would be interested to know for CFM engines as well as for IAE:
After the completion of the 30" manual crank following a manually aborted start (for any reason), how many cycles do you count for the starter, one or two?