trex8 From United States of America, joined Nov 2002, 4264 posts, RR: 14 Reply 1, posted (2 years 7 months 2 weeks 5 days 6 hours ago) and read 2321 times:
I think the issue is that the Trent 700 was designed for twins, so TO power (one engine out requirement) is substantially higher than cruise requirements for a similar aircraft of same weight but with more than two engines.
Bongodog1964 From United Kingdom, joined Oct 2006, 3329 posts, RR: 3 Reply 3, posted (2 years 7 months 2 weeks 4 days 12 hours ago) and read 1992 times:
The Trent 772 has around 72,000lb of thrust, the 556 around 56,000lb. Thus it has far more available power than required. i would imagine that the 772 is also heavier, and the wing might not be able to take the weight.
AA777223 From United States of America, joined Feb 2006, 1181 posts, RR: 7 Reply 4, posted (2 years 7 months 2 weeks 4 days 11 hours ago) and read 1936 times:
Quoting SASMD82 (Reply 2): If so, Airbus would have choosen to select the Trent 700s for the A345 and A346. I think this would have created the same 'problem' as with the A343: an underpowered aircraft.
I think the opposite problem would have occurred. The 776 generates 20K more lbs of thrust, per engine than the 556. This would be an OVERpowered aircraft... way overpowered.
trex8 From United States of America, joined Nov 2002, 4264 posts, RR: 14 Reply 6, posted (2 years 7 months 2 weeks 4 days 7 hours ago) and read 1731 times:
Quoting Speedbird128 (Reply 5): Quoting SASMD82 (Reply 2):
I think this would have created the same 'problem' as with the A343: an underpowered aircraft.
A340 is not underpowered. It has sufficient thrust provisions for its missions.
Sure it doesn't climb to A.nut requirements, but none have crashed because it was "underpowered".
As people who actually fly the A340 and 744 have said time and time again the A343 actually reaches cruise altitude quicker than a 744. If I understand them correctly to use a car analogy the 747s 0-30 acceleration may be faster but the A343's time to 60 is faster and speed at a quarter mile is higher.
Correction: I mean, the take off roll of A343 is loooooong and it climbs out slowly. The A345 and A346 climb out much faster. You are right, I meant an overpowered airplane.
Trex8, I agree: A fully loaded A772 (don't know about the 77W) for a mission such as AMS-LIM/EZE, it stays at 31,000 ft for a long time. After 6 or 7 hours, it climbs to a higher altitude. A fully loaded A343 (ICN-MUC) climbs to flight level 370 directly.