Originally Posted by
stiknruda
Just to be bloody pedantic:-
symmetrical wings in the Pitts family are not truly symmetrical - they are far closer to being symmetrical than the flat bottomed (M6) aerofoil but they are actually designed to fly similarly either way up - the nose attitude S&L inverted is still slightly higher than erect S&L.
Symmetrical ailerons in the same family are to all intents perfectly symmetrical!
I know that this doesn't really help much but it is a fuller picture!
Stik
I haven't seen a diagram of the Pitts S-1S wings to know but they could be perfectly symmetrical and still have a different attitude erect from inverted, depending on how they're mounted on the airframe, an angle known as "the angle of incidence".
Most wings are mounted to an airframe to produce sufficient lift to maintain S&L at a specified aircraft weight, airspeed and altitude but still have the hull of the aircraft level. For most light airplanes, this angle is usually only about 2 or 3 degrees, but that means that, to get the same amount of lift inverted, you have have the aircraft 2 or 3 degrees "wing" above the horizon, which will look like 4 or 8 degrees "nose above the horizon".
An extreme example of this is the B-52. It was designed to fly at 40,000 feet at 500,000 lbs but to be perfectly level and stable at that altitude to drop bombs accurately. Its wing is mounted to the fuselage at 17 degrees which means, when the aircraft attitude is straight and level, the wing is at an angle of attack of 17 degrees.
A few of the photos on this page show the wing mounting angle. You can see that near the leading edge of the wing, it intersects the upper part of the fuselage and they almost meet in the center. But the trailing edge of the wing hits the fuselage about midway down.
http://www.globalsecurity.org/wmd/systems/b-52-pics.htm
This also accounts for the fact that the B-52 climbs out from take-off in a distinct nose-down attitude because, in the denser air of low level, it doesn't need such a high angle of attack to maintain a climb. (couldn't find a good video for that)
Just to add further aerodynamic confusion!
Pitts2112
about the only thing my aero degree is actually useful for...