A question has come up in preparation for a Block exam. what are the two turning tendencies that occur during steep turn? If you know this may you please explain to me, why these tendencies occur. Cheers !

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    $\begingroup$ "The two turning tendencies"? During a steep turn, the aircraft's track tends to rotate into the turn, the heading tends to rotate along with the track but lag behind it, the pitch tends to decrease (which is to say, the nose tends to go down), and the bank angle tends to get steeper. All four of those tendencies involve a kind of "turning", so I can only guess which two of the four are "the two turning tendencies". $\endgroup$ – Terran Swett Sep 18 '18 at 13:48
  • $\begingroup$ Thank you for your reply $\endgroup$ – Scott Pearce Sep 19 '18 at 3:56

One of the turning tendencies that occurs during a steep turn is the tendency to over-bank. This is generally due to the outer wing (wing-up) moving faster thru the air and creating a bit more lift that has to be counter-acted. A second turning tendency is due to adverse yaw (requiring a bit more rudder during a right hand steep turn).

Here is a link that will help you understand:

aerodynamics of a steep turn

  • $\begingroup$ This type of overbanking tendency is characteristic of medium rather than steep turns. In a very steep turn, the outer wing does almost the same circle as the inner one. The adverse yaw effect is symmetric with respect to left/right; it is due to the drag associated with ailerons. The left turning tendency (on most aircraft) is associated with the engine and has little to do with turns. $\endgroup$ – Zeus Oct 9 '18 at 5:24
  • $\begingroup$ @Zeus- Sorry to disagree, but I have done a lot (probably thousands) of steep (and medium) turns with students in many different types of aircraft. The over-banking tendency varies in magnitude depending on the a/c but it exists and often requires a bit of opposite aileron to counteract. Yaw problem is definitely a characteristic of prop driven aircraft (again more noticeable in certain types). Of course, the same yaw issue is not present in jets, but there are unique handling characteristics in steep turns for all a/c types that are definable if you do a lot of training. Just my 2 cents... $\endgroup$ – 757toga Oct 9 '18 at 14:18
  • $\begingroup$ You probably did 50-60° bank turns. For GA, this is 'steep', but I meant steep as steeper than 60°. With these angles, this kind of overbanking gets smaller. Generally, this effect is rather exaggerated in pilots' minds; even a small un-balance (slip) will have a greater effect in most airplanes. 'Yaw problem' is (at least) two-fold: 'adverse yaw' is due to ailerons and is present even in jets and is not left/right specific; the prop reaction is characteristic of any stage of flight and not specifically a turn; and besides, OP didn't specify GA, which implies the answer should be generic. $\endgroup$ – Zeus Oct 10 '18 at 0:26
  • $\begingroup$ @Zeus - Jets, with perhaps minor exceptions, and some turboprops all have yaw dampers to resolve adverse yaw issues from the pilot perspective during normal ops. My experience in Boeing Jets and Lears vs light prop a/c has made me understand that adverse yaw is an important pilot-feel topic for light prop a/c and not so much for jets with a yaw damper. I did assume that the OP was talking about GA and was probably not being tested on banks exceeding 60 degrees. Could be I was wrong. I appreciate your comments and perspective. $\endgroup$ – 757toga Oct 10 '18 at 0:56

There are two: the overbankong tendency as a result of the outboard wing moving faster through the air and generating more lift than the inboard wing. The second is the left turning tendency as a result of P-factor, engine torque and spiral slipstream effects on the tailboom and vertical fin, requiring more right rudder to maintain a coordinated turn to the right than to the left.

  • $\begingroup$ This second effect has nothing to do with turns. It demands more right rudder (on most aircraft) even in a straight flight. The effect may marginally increase during the turn due to higher AoA and RPM, but it's still the same effect. $\endgroup$ – Zeus Oct 9 '18 at 5:30
  • $\begingroup$ Actually at high angles of attack it will be very noticeable. You will require considerably more right rudder to coordinate a steep turn. $\endgroup$ – Carlo Felicione Oct 9 '18 at 7:01
  • $\begingroup$ For most propeller driven aircraft designs the propeller shaft is parallel with the direction of flight eliminating (or nearly so) P-factor. Only a poorly engineered aircraft would require rudder deflection (and resultant useless drag) in level flight. $\endgroup$ – 757toga Oct 9 '18 at 14:37
  • $\begingroup$ @757toga That is incorrect. The engine crankshaft is permanently oriented relative to the longitudinal axis of the airplane. The angle between this and the relative wind varies with angle of attack. Consequently P factor varies as well. P factor is going to be a function of propeller angle of attack and engine power settings, and not whether the airplane is in level flight or not. $\endgroup$ – Carlo Felicione Oct 9 '18 at 15:13
  • $\begingroup$ @Carlo Felicione - a clarification is needed. Of course the the crankshaft is permanently orientated along the long axis, and the AOA will drive the magnitude of P-factor. My point is that when the a/c is flying S/L the crankshaft alignment is designed to virtually eliminate unnecessary yaw that needs to be offset by rudder deflection. As the a/c slows or any other pitch change resulting in increase of AOA, P-factor will be present. In S/L flight, at cruise AOA, properly trimmed a/c, no rudder deflection to offset P-factor is necessary. It's considered in the design of the A/C. $\endgroup$ – 757toga Oct 9 '18 at 15:51

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