A320 difference inflight- auto or manual start?

[IFLY_INDIGO]

In case of engine relight inflight - Is the procedure given in QRH for automatic start or manual start? proecdure never uses the MAN START pb. so is it autostart? but FADEC doesn't abort the start in case of any abnormality. so is it a manual start?

what is the important of the alt vs speed graph given in this procedure?

[ok45]

Its an autostart. But the fadec will not abort for you. The graph shows you how the start will be done by the FADEC, and make sure the engine is within the start envelope.

[vilas]

I FLY
Why would you do a manual start? In the air FADEC uses both igniters and leaves the decision to abort to you. That's all is achieved by manual start on ground. Whether to do a wind milling start or starter assisted is shown by the envelope.

[TyroPicard]

FADEC decides whether to use windmilling or starter-assisted relight. It cannot abort the start, in the interests of survival.... the decision is left to the pilot.
If for some (unknown) reason the start valve does not open when you expect a starter-assist, then the MAN START pb should open it. FCOM DSC refers.

[vilas]

Tyro
You are mistaking manual start with start valve manual operation. On ground when the start valve doesn't open you don't use manual start button but use supplementary procedure START VALVE MANUAL OPERATION in which the ground crew opens the valve from outside. This cannot be done in the air unless someone can go outside.

[IFLY_INDIGO]

If the start valve fails to open automatically in air in case of starter-assisted engine relight, it means that the only option left with the pilot is to speed up and hope for windmill relight.

[vilas]

That is correct and that is why MEL permits only one start valve inoperative.

[TyroPicard]

I am not talking about Manual Start Valve Operation.

FCOM DSC section under MANUAL STARTING..... the bottom line says...

In flight, the FADEC always commands a starter-assisted air start.

[vilas]

Tyro
I am talking about your following sentence:
If for some (unknown) reason the start valve does not open when you expect a starter-assist, then the MAN START pb should open it.
This is not correct. Failed start valve cannot be opened in flight. Even in dual engine flame out you only attempt auto starts.

[TyroPicard]

If for some (unknown) reason the start valve does not open
I did not say the start valve failed.....
I was merely pointing out that according to FCOM it is possible to do a manual start- assisted relight.

[vilas]

Tyro
Yes I would agree that it may be possible to use manual start in air although nowhere you find it is recommended.

[ok45]

If the start valve is faulty and wont open, the man start procedure is useless both in ground or in flight. FCOM PRO-ABN-70 P 29/68.
But like tyro said, it is possible to do man start in-flight. But why would that be the case?

[TyroPicard]

Maybe a scenario where you really, really need that relight but the Auto does not work correctly.... just as on the ground you might elect to try a Manual Start?

[vilas]

Just as I said in my first post auto start in air gives you exactly what manual start does on ground. Actually manual start is meant for use on ground but remains available in the air that's all, because in dual engine flame out even with repeated failure s to light up ECAM/QRH does not mention anything about manual start.

[IFLY_INDIGO]

auto or manual start [from the ovhd panel], FADEC only opens the start valve.

if start valve fails to open in flight, even manual start from ovhd panel is useless.

[Shatwa07]

whats the difference between auto start and manual start , when the pilot uses manual start.

[pineteam]

whats the difference between auto start and manual start , when the pilot uses manual start.

An Auto start will just do a normal robotic start: For IAE engines: Engine master ON: 30 seconds cranking and then one ignition comes alive and fuel will ignite ( unless ignition failure) regardless of the N1/N2 speed and EGT which can lead to start fault in some cases ( strong tailwind, very hot conditions.. etc)

Manual start you control the cranking time with the ENG man start p/b and control when to ignite the engines and send fuel ( With ENG Master sw to ON) and both igniters will be ON increasing your chance of a successful engine start.
For IAE engines, manual Start is recommended when:
**Tailwind greater than 10 kt.
** After aborting a start because of engine EGT over limit or low start air pressure or no N1 rotation or hung start.
** When expecting a start abort because of degraded bleed performance due to hot conditions or high altitude airports.
**Marginal performance or the external pneumatic power.
During manual start, the crew must pay attention to the starter limitations and since the FADEC has limited control, the crew must monitor the engine acceleration and be ready to abord the start if required as the FADEC has no authority to abort the start.

[Shatwa07]

Thanks 🙏 sir very helpful , appreciated .