Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!att!cbnews!military From: pvo3366@sapphire.oce.orst.edu (Paul O'Neill) Newsgroups: sci.military Subject: Re: Rotary engine airplane troubles Summary: combat use of torque Message-ID: <11069@cbnews.ATT.COM> Date: 3 Nov 89 04:19:57 GMT References: <10577@cbnews.ATT.COM> Sender: military@cbnews.ATT.COM Organization: Coastal Imaging Lab, Oregon State University, Corvallis, OR Lines: 54 Approved: military@att.att.com From: pvo3366@sapphire.oce.orst.edu (Paul O'Neill) In article <10577@cbnews.ATT.COM> entropy@pawl.rpi.edu (Speaker for the Clams) writes: > >................................. The result was that >these planes could execute very fast right turns but could >only turn left very slowly. > Does anyone know for sure if this is true? ...... >From _Fighter Combat Tactics and Maneuvering_ by Robert L. Shaw: ---------- Torque may also have an effect on turn performance, particularly with high-powered prop fighters at slow speed. The effects of engine torque must generally be offset by rudder power to maintain balanced flight. Normally under these conditions considerable right rudder will be required to balance the torque of a prop turning clockwise (when viewed from behind), and vice versa. Another consideration here is called "P-factor," which is the tendency of a propeller to produce more thrust from one side of its disc than from the other. P-factor usually affects the aircraft in the same manner as torque, and it is exacerbated by slow speeds and hard turning. Since even more rudder is usually required in the direction of a turn to maintain balanced flight, there may be conditions under which sufficient rudder power is just not available. The resulting unbalanced flight (slip) may cause loss of aircraft control. Generally the high wing (i.e., the outside wing in a turn) will stall, causing the aircraft to "depart" controlled flight with a rapid roll toward the stalled wing. This phenomenon has been used to good effect in combat, since it is more pronounced in some fighters than in others, and because prop-rotation direction may be reversed between combatants. The following World War II combat example to this tactic involves the P-38J Lightning versus the German Fw 190. The P-38 is a twin-engine fighter with counter-rotating props and essentially no net torque or P-factor. My flight of four P-38's was bounced by twenty-five to thirty FW-190's of the yellow-nose variety from Abbeville. A string of six or more of them got in behind me before I noticed them, and just as No. 1 began to fire, I rolled into a right climbing turn and went to war emergency of 60 inches manifold pressure. As we went round and round in our corkscrew climb, I could see over my right shoulder the various FW-190 pilots booting right rudder attempting to control their torque at 150 mph and full throttle, but one by one they flipped over to the left and spun out. ---------- Paul O'Neill pvo@oce.orst.edu Coastal Imaging Lab OSU--Oceanography Corvallis, OR 97331 503-754-3251