Originally Posted by
404GA
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
In general, 10 minute takeoff is needed when there are more distant obstacles to clear (e.g. more than 5 minutes but less than 10 minutes at engine-out speed, or a relatively tight turn is required that would be challenging with an engine out).