Originally Posted by KiloAlpha
I am well aware that you know more than me TP, so dont take this the wrong way. I dont believe your climb gradients are correct.
The 2.4, 2.7, 3.0 are for single engine climb with gear retracted 25.121
And when the aircraft reaches 400' agl, the climb gradient may not be less than 1.2, 1.5, 1.7 percent 25.111
I may be wrong though, please correct me if I am. This is a question I have also been trying to get answered... I am so confused
I think we agree on the second segment gradients. Just a little confusion on where second segment ends and third segment begins. I think your numbers on final segment are correct, I took the ones I used from a book I have on performance from the UK so they could be UK CAA numbers versus FAR numbers.
Here is some more info I found:
First Segment: begins at lift off and ends when the landing gear is fully retracted. The climb requirement in first segment is a positive gradient, out of ground effect, for two engine aircraft and 0.3% for three engine aircraft. The rotation speed, Vr, must be selected so that V2 is achieved by the time the aircraft reaches 35 feet in the air.
Second Segment: begins at the end of first segment and is continued to not less than 400 feet above the airport elevation. The climb requirement in second segment is 2.4% gradient for two engine aircraft and 2.7% for three engine aircraft. Second segment is usually, but not always the most limiting of the segments within the takeoff flight path.
Third Segment: begins at the end of second segment and ends when the aircraft reaches the speed for final segment.
While third segment is usually flown in level flight, the available gradient must be at least equal to that required in final segment. During third segment the high lift devices are retracted.
Final Segment: begins when the aircraft reaches the final segment speed and ends when the aircraft reaches 1500 feet above the airport elevation. The climb requirement in final segment is 1.2% gradient for two engine aircraft and 1.5% for three engine aircraft. At the beginning of final segment, the power is reduced to maximum continuous. Each segment must be flown at a constant power setting and the end of the acceleration segment is often coincident with the end of the five minute limitation on Takeoff thrust.
These numbers pertain only to turbojet/turbofan aircraft not recip/turboprop aircraft.
TP