9V-SPJ From United States of America, joined Dec 2000, 758 posts, RR: 0 Posted (10 years 6 months 4 weeks 8 hours ago) and read 5063 times:
I have one question about the B757-200's climb performance. Would it be able to climb straight to 36000ft without step climbing after taking off at MTOW and sea level?
My next question is: what is the coefficient of rolling friction for a wet runway in the USA? I tried looking for the value on FAA's website, but found nothing.
Rick767 From United Kingdom, joined Jan 2000, 2662 posts, RR: 50
Reply 2, posted (10 years 6 months 4 weeks 3 hours ago) and read 5030 times:
Bear in mind that the 757-200 has an MTOW of up to 115,650kg (255,000lb) for some models, and at this weight the optimum cruise altitude is about 32,000ft (so you really wouldn't want to climb much above that - 33,000ft or 34,000ft maybe).
The 757-200 with Rolls Royce RB211-535E4 engines has a thrust limited maximum operating altitude of 35,400ft at 115,000kg gross weight and additionally the buffet margin is narrow above 105,000kg at this altitude.
But say you took off at 100,000kg (220,500lb), then it should be no problem, but again you would still want to wait to be down in the 90,000kg gross weight region before stepping to this level in view of economy (optimum alt).
I used to love the smell of Jet-A in the morning...
Taguilo From Argentina, joined Aug 2005, 74 posts, RR: 0
Reply 3, posted (10 years 6 months 4 weeks 2 hours ago) and read 5016 times:
Quoting Rick767 (Reply 2): The 757-200 with Rolls Royce RB211-535E4 engines has a thrust limited maximum operating altitude of 35,400ft at 115,000kg gross weight and additionally the buffet margin is narrow above 105,000kg at this altitude.
What would mean if you keep climbing beyond that altitude? Should happen a reduction of power/speed and finally it would become impossible to hold leveled flight; or is it possible to have a flame out/engine stall even before the point where lift can't be sustained?