Aseem From India, joined Feb 2005, 2046 posts, RR: 9 Posted (9 years 11 months 2 weeks 5 days 22 hours ago) and read 2761 times:
the climb rate of A343 is not news to anybody, but one does not come across discussion about A333s. That leads one to believe that climb rate is not an issue with the latter. Considering there isn't much difference between the size of both, then why does A343 climb slower than A333 in spite of having two more engines.
UAL747 From , joined Dec 1969, posts, RR:
Reply 1, posted (9 years 11 months 2 weeks 5 days 22 hours ago) and read 2742 times:
Most likely it is due to the fact that the A330 has a higher thrust to weight ratio than the A343. When the A340 was designed, it was designed for optimal effeciency of that era's modern technology. Lower thrust, smaller engines, more fuel savings. The A330 was not originally designed to be a long-haul aircraft, even though nowadays, it is. That's just in layman's terms. You can find better information from others.
Trex8 From United States of America, joined Nov 2002, 5533 posts, RR: 14
Reply 2, posted (9 years 11 months 2 weeks 5 days 21 hours ago) and read 2610 times:
this has been discussed by others far more knowledgeable than myself but in a nutshell, a twin engined plane needs sufficient thrust from one engine to continue a take off when one engine is out, while a quad only needs enough thrust from 3 engines, or looked at another way, a twin must have engines capable of twice the thrust it needs to take of, while a quad only needs 33% more, the result is a twin is always "overpowered" relative to a comparably sized quad.
Antares From Australia, joined Jun 2004, 1402 posts, RR: 38
Reply 3, posted (9 years 11 months 2 weeks 5 days 21 hours ago) and read 2610 times:
From reasonably frequent observation flying CX out of Sydney, the A330 climbs faster than the A343. For example, we usually seem to go straight to either 36,000 feet or 38,000 feet on departing Sydney on the former but in the low 30s for the latter, although it usually seems to reach 39,000 feet or more, I'm fairly certain I've seen 41,000 feet toward the end of the stage either way more than once.
The A346 is sometimes on the route. It went again to 36,000 or 38,000 feet straight off.
I've now flown the A345 with EK several times to Auckland (before it was replaced by the 773) and to Dubai. The Tasman stage seemed to be at 40,000 feet both ways, certainly higher than is usual on the smaller jets. Going to Dubai out of both Melbourne and Sydney late at night we went straight to the mid 30s, I think 35,000 or 36,000 feet. However I haven't flown the route in reverse so I can't comment on departures from Dubai, other than to say going to Europe the 777s and A330s both went to the low 30s and stayed there, perhaps as much to do with ATC requirements as anything else, since you do notice a bit of traffic in that part of the world.
The highest altitude I've ever noticed on a commercial jet other than Concorde was something above 43,000 feet on a Qantas SP a few hours out from Sydney coming in from the US.
However back in the days of Comet IV services for BOAC out of Essendon Airport in Melbourne we'd get to 40,000 feet on the stage to Darwin routinely.
I think the windows on the old Comets will actually prove to have been bigger than anything we will see on a 787, but nowhere as interesting of course.
ManchesterMAN From United Kingdom, joined Sep 2003, 1257 posts, RR: 1
Reply 4, posted (9 years 11 months 2 weeks 5 days 21 hours ago) and read 2590 times:
I was thinking about this just last week when sitting in the loune at PHL overlooking the runway. A LH A343 took off and very slowly climbed (I love this "feature" of the A343 BTW) and shortly afterwards a US A333 departed like a rocket in comparison. So yes the A333 does climb faster than an A343 in typical operation
Bomber996 From United States of America, joined Aug 2005, 462 posts, RR: 0
Reply 5, posted (9 years 11 months 2 weeks 5 days 20 hours ago) and read 2553 times:
Could also have to do with the MTOW. Remember the A330 and A340 share the same basic wing. basic logic will tell you when you have the same lifting body, but lower weights on one, the lower weight will have the optimal performance. Look at the A319 vs. the A320, DC9-15 vs. DC9-20, etc. Also the A330 has more available thrust than the A340 as explained above. Here are the stats:
Ap305 From India, joined Jan 2000, 886 posts, RR: 0
Reply 7, posted (9 years 11 months 2 weeks 5 days 16 hours ago) and read 2309 times:
As Bomber996 says its probably down to the wing loading as much as it is to the thrust/weight ratio. The a330 is one of the few aircraft that climb straight to fl360-370 straight after departure. The "climb rate" does tend to be somewhat slow on occasions as a climb de-rate is used a lot of times in addition to the flex-thrust on takeoff.