"normal" takeoff requires familiarity with the aircraft
Quote:
Originally Posted by
raytoews
I watched the new video of the Subsonex test flight. Really neat view from the pilots perspective. I noticed during the takeoff roll he seemed to pull the stick full back and as the nose came off he lowered the nose to takeoff attitude.
I know from watching videos that is the way carriers planes do it but they are being assisted rather strenuously.
I would think this would introduce drag from full up elevator deflection the same reason I don't lower flaps until just at rotation.
Is this a technique others use, is it unique to jets or to just this pilot.
Always something new,,,eh?
ray
As any commercial or twin pilot will tell you, the "normal" takeoff requires familiarity with the aircraft.
You (the pilot) are expected to reach VR and know what back pressure is needed for the aircraft to rotate to a natural climb attitude. Of course all bets are off for other than "normal" takeoffs. The point of this is that a "professional" pilot with a familiar aircraft would not normally make very much adjustment after VR. One explanation for the video you cited was an early test flight might have warranted the pilot to hold the aircraft on the ground a little bit longer for a safety margin then "pop" the aircraft into ground effect until VY is reached. Gusting winds or a crosswind would have also warranted the pilot to do as you noted.
A normal takeoff (for me personally) in a single engine aircraft is to rotate at VR (just before or 1-2mph over VS) and lift off at VS +10%, accelerate to VX and then when prudent lower the nose to VY. The reason for this is to put the aircraft in VX as soon as possible which is also coincidentally the best L/D speed, so the aircraft is immediately in the emergency configuration during the upwind leg of the pattern. If something goes wrong no adjustment is needed to the airspeed.
There is no comparison to turbines and reciprocating engines because jets have an enormous amount of reserve /excess power - for example commercial airliners do not use a "normal" VR because they take into account a phenomenon known as inertial acceleration (due to excess power) and their VR is substantially lower than the VS stall speed.