P factor and pitching moment?

necoflyer

Well-Known Member
We have all heard that P-factor makes the plane turn to the left and is caused by the downward travelling blade having a greater angle of attack blah blah blah.

My thought is, there must be P-factor working on the horizontal plane of the prop. Would only happen in uncordinated condition, such as slip to land. Example: landing in a left crosswind, holding right rudder, dipping the left wing causes the relative wind to be from the left of the nose. The blade on the bottom of the prop, travelling to the left, would have a greater angle of attack than the blade on top, moving to the right. This would cause a pitch up moment. Likewise, in a right crosswind, with the relative wind comding from the right, the blade coming over the top has the greater AOA, thus causing a pitch down moment.

So am I correct in this thinking, or out in left field? How much of a pitching moment is there, and would these be noticable to the pilot, or would they be so minor they go unnoticed?
 
We have all heard that P-factor makes the plane turn to the left and is caused by the downward travelling blade having a greater angle of attack blah blah blah.

My thought is, there must be P-factor working on the horizontal plane of the prop. Would only happen in uncordinated condition, such as slip to land. Example: landing in a left crosswind, holding right rudder, dipping the left wing causes the relative wind to be from the left of the nose. The blade on the bottom of the prop, travelling to the left, would have a greater angle of attack than the blade on top, moving to the right. This would cause a pitch up moment. Likewise, in a right crosswind, with the relative wind comding from the right, the blade coming over the top has the greater AOA, thus causing a pitch down moment.

So am I correct in this thinking, or out in left field? How much of a pitching moment is there, and would these be noticable to the pilot, or would they be so minor they go unnoticed?


In the situations you described I think there would definitely be a P factor working on the aircraft. There is some kind of P factor working on the plane anytime a change in velocity, acceleration, occurs. However usually when you are in a slip whether it be a forward slip to lose altitude or a side slip to land in a crosswind you are usually at a very low pawer setting if not at idle. I think the effects would be negligible
 
We have all heard that P-factor makes the plane turn to the left and is caused by the downward travelling blade having a greater angle of attack blah blah blah.

My thought is, there must be P-factor working on the horizontal plane of the prop. Would only happen in uncordinated condition, such as slip to land. Example: landing in a left crosswind, holding right rudder, dipping the left wing causes the relative wind to be from the left of the nose. The blade on the bottom of the prop, travelling to the left, would have a greater angle of attack than the blade on top, moving to the right. This would cause a pitch up moment. Likewise, in a right crosswind, with the relative wind comding from the right, the blade coming over the top has the greater AOA, thus causing a pitch down moment.

So am I correct in this thinking, or out in left field? How much of a pitching moment is there, and would these be noticable to the pilot, or would they be so minor they go unnoticed?

Very interesting observation, I think you just explained why the nose initially pitches up when also practicing the forward slip to a landing. I have been doin some primary instructing lately (first time in a while) and have almost forgotten aobut this phenomenon that I witnessed again just the other night. Just so happened to be that both were performing a forward slip with left wing down. Student mashes the rudder to the floor, corrects appropriately with aileron, and the nose rises sharply for a couple of seconds, requiring a fair amount of nose down elevator! Good job!
 
Very interesting observation, I think you just explained why the nose initially pitches up when also practicing the forward slip to a landing. I have been doin some primary instructing lately (first time in a while) and have almost forgotten aobut this phenomenon that I witnessed again just the other night. Just so happened to be that both were performing a forward slip with left wing down. Student mashes the rudder to the floor, corrects appropriately with aileron, and the nose rises sharply for a couple of seconds, requiring a fair amount of nose down elevator! Good job!

However, now that I think about my own post here, p-factor is also relative to the power setting, if one is at a low or idle power setting, p-factor should actually be un-noticable!

Things that make you go ....hmmm....
 
In the situations you described I think there would definitely be a P factor working on the aircraft. There is some kind of P factor working on the plane anytime a change in velocity, acceleration, occurs. However usually when you are in a slip whether it be a forward slip to lose altitude or a side slip to land in a crosswind you are usually at a very low pawer setting if not at idle. I think the effects would be negligible

read your post after my own...I catch on eventually!!
 
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