[g zero]

Anyone ever put a level on the upper longerons in flight ? Just curious .
Tom

 

[Yen]

A level would not necessarily read true, it works just the same as your ball, so it could read the same all the way round a loop.

 

[BlackhawkSP]

Level in flight

So you're saying that when the nose is pointed straight up in the beginning of the loop that the bubble would stay in the center of a glass vial on a level ? I don't think that's correct. A level that's aligned with the longitudinal axis of the aircraft will show nose up/down excursions from level I would think. I think I'll take my smart level up next time and see if the 1G pull up will fool the digital portion of the level, but I'm pretty sure the bubble will go to the top of the vial.

 

[rzbill]

I think the OP is wondering whether the longerons are level longitudinally (pitch) when in straight and level 1G flight.

Of course in this case, the bubble position will change with velocity. Maximum out of level at stall of course, so the question must be qualified with a speed. Assumption is the question is at 75% cruise. It will be an indication of the designers choice on wing incidence since incidence influences fuselage position relative to wing chord line and its angle of attack.

In regards to the bubble moving during positive G aerobatics, have you never seen the video of Hoover pouring tea from pitcher to glass in a roll? He obviously has the lift vector by the ()s and is not letting it move one whit.