MarkC From United States of America, joined Apr 2006, 259 posts, RR: 0 Posted (8 years 11 months 4 days 5 hours ago) and read 4391 times:
Anyone know why Airbus stopped with the -300? Seems to me they could have gone a little longer and used 777 class thrust engines....plenty of those available. I don't think it was ground clearance. On the PW4000, the 777 engines are only 12 inches larger in diameter.
LTU932 From Germany, joined Jan 2006, 14095 posts, RR: 47
Reply 1, posted (8 years 11 months 4 days 4 hours ago) and read 4380 times:
Good question, which leads me to this what if: what if Airbus decided to stretch the A330 to the dimensions of the A340-500 and -600 and not the A340? Or simply put (apart from the 4 engines 4 longhaul thing): why didn't they go with the twin platform for the stretch instead of the quad?
Starlionblue From Greenland, joined Feb 2004, 17381 posts, RR: 66
Reply 2, posted (8 years 11 months 4 days 4 hours ago) and read 4373 times:
< speculation >
Probably because the wing can't really handle that. The 345/346 wing is heavily modified compared to the 332/333/342/343 wing. My guess it requires the outboard engines in place to mitigate wing bending moment. Making it a twin would either require wing reinforcement (the 332/333 wing is already reinforced compared to the 342/343 wing for this exact reason) or moving the engines outboard. Moving the engines outboard would have required pretty much a new wing so that was out.
Furthermore, for the mission (very long haul), it is by no means a given that fuel consumption for a "335/336" would be less than for the 345/346. As I understand it, on long routes the 340 is more efficient than the equivalent 330. This is all before engine maintenance costs of course.
< /speculation >
"There are no stupid questions, but there are a lot of inquisitive idiots."