OEI 5 min TO ppwer vs 10 min TO power
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OEI 5 min TO ppwer vs 10 min TO power
I'm trying to understand the performance differences between a business jet who is certified for One Engine Inoperative (OEI) take off power of 5 minutes vs the same model whose engines are certified for OEI TO power of 10 minutes. If a SID departure requires a climb gradient of 400 feet per NM, shouldn't either aircraft have the same weight limits? From what I've seen in the performance charts, the 10 minute aircraft can go with a slightly higher weight. This just doesn't make sense to me so I must be missing something. Thank you.
t
t
I'm trying to understand the performance differences between a business jet who is certified for One Engine Inoperative (OEI) take off power of 5 minutes vs the same model whose engines are certified for OEI TO power of 10 minutes. If a SID departure requires a climb gradient of 400 feet per NM, shouldn't either aircraft have the same weight limits? From what I've seen in the performance charts, the 10 minute aircraft can go with a slightly higher weight. This just doesn't make sense to me so I must be missing something. Thank you.
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Used to fly the same type which had both 5 and 10 minutes on the fleet. Some frames were 5 minutes, others 10. As the engines all got swapped around, it was all pretty much nonsense and was driven by the tail number rather than anything to do with the engines.
The airframer also has to make some changes to EICAS (or the equivalent) as the takeoff EGT (and sometimes rotor speed limits) are higher for TO than Max Con, so the exceedance logic needs to reflect that.