What exactly do “attempt” and “cycle” mean in these starter duty limitations?
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What exactly do “attempt” and “cycle” mean in these starter duty limitations?
Hello Professional Pilots and Engineers Seasons Greetings.
Can someone please explain me this... A320 Starter Duty Limitation in simple terms?
E.g. for the CFM56 Starter:
Then 20 Seconds gap.
Then Next Cycle and so on and then say after 4 unsuccessful cycles I got to wait for 15 min.
But things get confusing between words Cycle and attempt.
Since for another type of Engine it says
I am newly released Commerical Pilot pursuing A320 Type Rating. Help from experienced A320 Pilots and Engineers is highly appreciated.
Can someone please explain me this... A320 Starter Duty Limitation in simple terms?
E.g. for the CFM56 Starter:
No running engagement when N2>20% 4 cycles of max 2 mins
Pause between start attempts . . . . . . . . . . . . . . . . . .. . . . . . . . . 20 sec
Cooling period after 4 attempts . . . . . . . . . . . . . . . . . . . . . . . . . 15min
Does it mean the moment I put Engine Master to ON till Automatic abort by FADEC in case of Automatic Start or Manual abort by turning the engine master and man start button off (limiting it to 2 mins) in case of Manual start = 1 Cycle.Pause between start attempts . . . . . . . . . . . . . . . . . .. . . . . . . . . 20 sec
Cooling period after 4 attempts . . . . . . . . . . . . . . . . . . . . . . . . . 15min
Then 20 Seconds gap.
Then Next Cycle and so on and then say after 4 unsuccessful cycles I got to wait for 15 min.
But things get confusing between words Cycle and attempt.
Since for another type of Engine it says
Auto start with up to 3 start attempts is 1 cycle.
Between successive cycles – 20 seconds pause (for auto or manual ground starts).
After 4 failed cycles – 15 min cooling period.
What is attempt and what is cycle? I hope someone explains it in real simple terminology.I am newly released Commerical Pilot pursuing A320 Type Rating. Help from experienced A320 Pilots and Engineers is highly appreciated.
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Hello,
Attempt is the process that FADEC follows to start an engine . So when the pilot turns the MASTER switch on, the FADEC initiates a start attempt.
In case the engine doesn't start, FADEC can perform another attempt automatically ( the pilot does not have to do anything to the master switch).
If the engine still doesnt start , the crew turns the master switch off.
The action of turning the switch back on is a new cycle. This new cycle will include single or upto 3 start attempts by the FADEC depending whether the engine starts or not .
So, understanding the limitation with steps involved
1. Pilot turns the master switch on ( first cycle ) , the FADEC initiates the process of engine start giving 3 attempts ( 2nd and 3rd attempt if engine doesn't start the first attempt . this is automatic )
2. Engine fails to start , pilot turns the master switch off
3. Pilot waits for 20 seconds
4. pilot turns the master switch on - this becomes the second cycle .
Therefor :
Pilot action of turning the master switch off and then on is a cycle
FADEC internal procedure of starting the engine is called attempt .
hope this helps
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COM_A320
Attempt is the process that FADEC follows to start an engine . So when the pilot turns the MASTER switch on, the FADEC initiates a start attempt.
In case the engine doesn't start, FADEC can perform another attempt automatically ( the pilot does not have to do anything to the master switch).
If the engine still doesnt start , the crew turns the master switch off.
The action of turning the switch back on is a new cycle. This new cycle will include single or upto 3 start attempts by the FADEC depending whether the engine starts or not .
So, understanding the limitation with steps involved
1. Pilot turns the master switch on ( first cycle ) , the FADEC initiates the process of engine start giving 3 attempts ( 2nd and 3rd attempt if engine doesn't start the first attempt . this is automatic )
2. Engine fails to start , pilot turns the master switch off
3. Pilot waits for 20 seconds
4. pilot turns the master switch on - this becomes the second cycle .
Therefor :
Pilot action of turning the master switch off and then on is a cycle
FADEC internal procedure of starting the engine is called attempt .
hope this helps
For interesting content on A320 technical ( quiz, posts) , do check us out
Instagram : Childrenofmagenta_a320
Website : www.compilottraining.com and click on pilot resources
Happy learning,
COM_A320
I have always thought that an attempt is the period during which the air starter is powered, and a cycle is a start attempt followed by a cooling period?
I am confused by what is quoted for "another type of engine" with three start attempts being one cycle??
The timing starts when the air starter bleed air valve opens.
I am confused by what is quoted for "another type of engine" with three start attempts being one cycle??
The timing starts when the air starter bleed air valve opens.
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In the CF6, for example, Autostart wil retry a start without intervention if it does not get lightoff in a certain time. In many cases it turns off the fuel without disengaging the starter, keeping the engine motoring. Then fuel and ignition are re-introduced. These 3 attempts without manual intervention would be 1 cycle.
