I was hoping someone could quote me the correct/up to date answer from the CARS or AIM for the IATRA study topic discussing climb gradients for multi-engined airplanes. I have seen two different answers, and have not been able to find anything super recent.
One source says:
2.4 degree gradient for two engines
2.7 degree gradient for three engines
3.0 degree gradient for four engines
Then an advisory circle says 1.2, 1.5, 1.7 degrees for two, three and four engines respectively.
Any help would be appreciated!
IATRA Question: Req’d climb gradient
Moderators: sky's the limit, sepia, Sulako, Right Seat Captain, lilfssister, North Shore
Re: IATRA Question: Req’d climb gradient
Could the advisory be talking about performance with an engine out?
As an AvCanada discussion grows longer:
-the probability of 'entitlement' being mentioned, approaches 1
-one will be accused of using bad airmanship
-the probability of 'entitlement' being mentioned, approaches 1
-one will be accused of using bad airmanship
- Col. Panic
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Re: IATRA Question: Req’d climb gradient
You’re mixing up units. It’s 2.4/2.7/3.0 % (percent), which roughly equates to the 1.2/1.5/1.7 degrees. Remember a 100% slope is 45 degrees (rise 1 foot for every foot of run), so the degree value is about half the percent value.
And these values must be maintained in the second segment climb, following an engine failure at V1.
And these values must be maintained in the second segment climb, following an engine failure at V1.
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Re: IATRA Question: Req’d climb gradient
2.4% gradient is the certified climb limit for two engine aircraft in the 2nd segment, which must be achievable in whatever takeoff conditions irrespective of terrain.
The 1.2% gradient is the required 3rd segment climb capability as the aircraft accelerates from takeoff to clean configuration.
The 1.2% gradient is the required 3rd segment climb capability as the aircraft accelerates from takeoff to clean configuration.