N229NW From United States of America, joined Sep 2004, 1972 posts, RR: 31 Posted (10 years 3 months 3 weeks 1 day 12 hours ago) and read 5456 times:
Please forgive me if this has been answered (I couldn't find it from a search of this forum), or if it is a stupid question...
Are there certain aircraft, weather or load conditions in which the flaps are not set on takeoff? Many years ago I was on an Air France A300 Paris to LHR, sitting over the wings, and I noticed that we took off with no visible flap deployment. I was actually scared at the time, since this was just after the NW MD-80 crash in Detroit caused by flaps in wrong position on takeoff....
Anyway, we took off fine. And this never happened to me again on any other flight I can remember... till about 13 years later, I took a Lufthansa A300 from Berlin to Frankfurt. Once again, no visible flap on takeoff.
Both times this was an A300, with a full pax load, but a very low fuel load (short flights). Anyone have an explanation for me?
Saleem From Pakistan, joined Mar 2000, 197 posts, RR: 0
Reply 4, posted (10 years 3 months 3 weeks 1 day 1 hour ago) and read 5305 times:
This was also my questions and answered by an A300 Pilot, that A300 uses no flaps on takeoff. Further, one thing, for which I need confirmation that the Airbus A300 is the plane which does not have flexibility in its wings. So, A300's wings do not bend on Takeoff, so you cannot see wing flex on A300. Is it so??
SlamClick From United States of America, joined Nov 2003, 10062 posts, RR: 68
Reply 6, posted (10 years 3 months 3 weeks 1 day ago) and read 5288 times:
Think I remember seeing "NO-FLAP TAKEOFF OK" stencilled on the upper side of the wing, so that it could be read out the passenger windows. Could this have been on an F-100? I assumed that it was to keep people from ringing the f/a calls or jumping up when takeoff started without flaps down.
Happiness is not seeing another trite Ste. Maarten photo all week long.
Starlionblue From Greenland, joined Feb 2004, 17185 posts, RR: 66
Reply 8, posted (10 years 3 months 3 weeks 21 hours ago) and read 5223 times:
The A300 used an early supercritical airfoil. This was so much more efficient than predicted that several flap settings were deleted before entry into service.
My guess is that the F100 airfoil was bult so as not to need flaps on takeoff. IIRC it doesn't have slats either.
I would speculate that the fact that the 767-200 can and the -300 cannot do a no flaps takeoff depends on the relative weights of the airframe. Since the wing can support the -300 (and with a mod the -400) it can lift the -200 with relatively more ease, thus the no flaps takeoffs.
"There are no stupid questions, but there are a lot of inquisitive idiots."
Manburkert From China, joined Sep 2004, 19 posts, RR: 0
Reply 14, posted (10 years 3 months 2 weeks 6 hours ago) and read 4763 times:
Extending of flaps has a similar affect as increasing pitch by the cost of higher drag. For an efficient flight its mandatory to keep the drag as low as possible.
The other factor is the speed during t/o. When the Aircraft can reach the needed speed on the runway then every plane can start without extracted flaps.
But that means the limitation is the runway length, and also the tires are limited in their maximum speed.