Friday, March 27, 2015

TBU/TBY Wing Fold

Somebody asked for details on the TBU/TBY wing fold area because it isn't covered in detail in Steve Ginter's monograph. Note that there are two hinge points, one on the main spar and one on the forward spar, and a large bellcrank that is driven by two actuators, one in the inboard wing and the other in the outer.

There was one confusing element, an oval panel with pointed ends on the upper surface of the wing over the wing-fold area. The panel was necessary to provide an opening for the outer wing to fold past vertical.

I initially assumed that the panel was metal and part of the outer wing but I couldn't figure out how it didn't interfer with the hinge on the main spar. I finally realized that it was something like canvas (perhaps a rubberized fabric) and simply folded in on itself.

Here the cover appears to be bulging upward from aerodynamic pressure in flight.

This illustration shows the location of the main spar hinge relative to the forward hinge point and the cover

This was the only other picture that I could find of the fold area. It shows the lower half of the wing-fold actuator bellcrank and the inboard actuator.

Monday, March 9, 2015

F8U Underwing Details

There isn't much to be seen under the wing of an F8U when it is raised, even the underside of the wing itself.

Note that there was only one actuator to raise and lower the wing (the F8U-3 had two).

The top of the fuselage can barely be seen although this is what it looks like with the wing removed, looking forward from the pivot point.
There's a lot of white overspray on this derelict fuselage. The forward bulkhead should be red. The duct on the right side is covered with a silver insulation. Some of the piping was green zinc chromate. There is also a red fuel filter or something along the right forward side.

Tom Weinel has done some research and concluded that the area was green up through the early 1960s (e.g. F-8Es) and then painted white during Navy overhaul at some point or when the F-8s were rebuilt by Vought.