tsands

My Feedback: (3)

Is there a way to set the incidence on a pete n poke without having a meter. It is suppose to have on + degree of incidence in the wing. THANKS

Campy

My Feedback: (1)

You can do with a calibrated level.

Block the plane up and insure the horizontal stab is level. The place the calibrated level on the wing (you will probably need to use the underside of the wing since it is flat ) and see what the incidence is, then adjust as needed.

MinnFlyer

My Feedback: (4)

I don't know what the incidence is SUPPOSED to be, but you could make a home-made incidence meter to check it.

tsands

My Feedback: (3)

The incidence is supposed to be positive 1 degree. The sad part is, I dont even know what that means. I leveled the stab and that is as far as I got.[]

Would positive 1 degree put the front higher or lower?? Sorry for my incompetence on this subject[:@]

Countryboy

My Feedback: (25)

tsands,

Here are a few pics showing the process for checking incidence on a Bi-Wing using a Robart incidence meter.. Positive incidence means the leading edge would be higher than the trailing edge...and negative for the opposite. As you can see from the pics, my Pitts has 1 degree positve in the H-stab, 0 degree on the bottom wing, and 1 degree positive on the top wing.

khodges

My Feedback: (1)

tsands, to explain incidence a bit further, if you draw a line from the tip of the spinner through the end of the tail (think of the plane in profile) the incidence of the wing would be the angle relative to that line, of another line drawn through the wing from middle of leading edge through trailing edge (chord line of wing).

A flat-bottom wing with zero incidence would have its chord line parallel to the line down the plane's long axis, positive incidence would have the leading edge a bit higher, negative a bit lower. Many full size planes have different incidences for the right and left wing, maybe only a 1/2 degree or so, to help counter engine torque's tendency to roll the airplane. The greater incidence in one wing creates a little more lift on that side.

Countryboy's Pitts has different incidences in the wings so the top wing will stall before the bottom wing, which will cause the plane's nose to drop when it stalls; if the bottom wing stalled first, the plane would tend to pitch up, aggravating the stall condition.

tsands

My Feedback: (3)

What would happen if the incidence is off on a Pete n Poke? I may have screwed up. The front of the wing is a bit low. I can shim it up if need be. Obviously I'll need to since I have negative in it now. Man I may have really screwed up. Hopefully shims work. This wing if flat bottom with about 14 inch chord. Any suggestions are greatly appreciated.

BillS

You shouldn’t get carried away with exactness until your flying skills can tell the difference. Even large mistakes can be trim corrected.

If your patience is good you can measure and calculate the incidence. Some trig required. Set the horizontal stabilizer level. Measure the leading and trailing edge of the wing and calculate the angle. With an incidence meter it is a little easier but not necessary.

If your flying skills are good you can shim and test. Many pilots cannot tell the difference in one degree of incidence.

All three ways work and the experience is educational.

Bill

Daryl_y

the sine of 1 deg is .017 so for every inch 1 a degre angle rises or falls .017" What I would do is set the horizontal stab level and measure the length of the flat part of the bottom of your wing and multiply that by .017 so if the flat part of your wing is 10 inches long they would have to measure .170" or 11/64 different to be at 1 deg. Having a good scale that measures in decmil inches would make this a little easier.

Daryl_y

doh!! double post just deleted it

tsands

My Feedback: (3)

Thanks for all the replies guys. I went ahead and epoxied the struts level with the hor stab level so incidence should be zero??? AGAIN, THANKS