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777X test
Source: Boeing 777X Takeoff for its First Flight

Is this from a low payload and the configuration of flaps? Or perhaps a pilot pushing the yoke forward while the plane wants to lift?

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    $\begingroup$ Answer here: What main landing gear actuator does the Boeing 777-300ER have? Though I'm not sure if it qualifies as a duplicate. $\endgroup$
    – ymb1
    Jan 25 '20 at 22:41
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    $\begingroup$ This is an optical illusion, as the nose gear aligns with the edge of the runway. It is actually at least 3-5 feet off the runway when the right gear lifts off. The nose gear lies midway between the left and right mains in the roll plane. In order for it to be in contact with the runway when the right main lifted, the plane would have to pitch down. That is not what happened here. $\endgroup$ Jan 27 '20 at 0:03
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    $\begingroup$ I gotta say, at this time stamp the right MLG is definitely off the ground, but there still appears to be a plume of spray behind the nose wheel. If you watch full screen on a large monitor, it very much seems to be there. It's not until here that I can see the nose wheel lift. $\endgroup$
    – FreeMan
    Jan 28 '20 at 22:40
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Correct on both guesses to some extent I would say. The airplane is pretty light, and with flaps down the flapped area of the wing is operating at a positive AOA (remember that the chord line is from the LE of the slat to the TE of the flap, so with flap down there is positive AOA even while 3 point).

Also as it's an initial test flight I wouldn't be surprised if the pilot delayed rotation past normal Vr 5 or 10 kts just to have some extra energy margin if something went amiss, so not necessarily holding the nose down, but delaying pulling it up.

Added together, maybe helped by a bit of crosswind coming from that side, you get the truck starting to come off before rotation.

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    $\begingroup$ The long 777s' MLG being semi-levered (designed to force an early actuation TE down) is a big factor too. A 777-200's MLG would have tilted the other way (remaining flat to the runway). $\endgroup$
    – ymb1
    Jan 25 '20 at 23:18
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    $\begingroup$ and maybe he tried to keep it down for the cameras as well, give the press and marketing guys a few extra seconds to get their photos of the first takeoff. $\endgroup$
    – jwenting
    Jan 27 '20 at 6:39

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