[fingpilot]

Typical test flight routine will be to stay well within a safe engineering parameter. As the time aloft and the data numbers start to accumulate, each parameter will be slowly expanded, eventually going somewhere around 115% to 130% of limit.

I did several years of production test flying for Gulfstream in Savannah. I never worried about being out on the line in service ever again after that. Having seen what is done to every greenie prior to delivery.

Wing flex? Sit over the wings in a 747-400, gross weight takeoff. Taxiing out, the winglets, with droop, are below line of sight. Airbourne, the line of sight is mid-wing. Tops of winglets are almost tough to see sitting next to window. I believe I heard 17 feet of flex from droop to top of stable flex. More in turbulence.

My standard line to squeemish passengers was that the plane was stressed for far more G's that the human body.

Design parameters? Human being? 6-ish MPH. 1 G. 15 foot fall. 14.7 psi nominal. 45 to 100F. Anything else requires a mod to avoid death. I would usually remember these parameters on the bike when trail braking into a corner a little too fast. Also on takeoff at gross passing EFCA (engine failure cleanup altitude), calling for slat/flap retraction. Would always look over my shoulder at the outboard nacelle, straining at the pylon, condensate filling the inlet.

A lifetime of mental pictures, impossible to duplicate, except thru writing about them.