Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 8/21/84; site idi.UUCP Path: utzoo!utcs!lsuc!pesnta!idi!kiessig From: kiessig@idi.UUCP (Rick Kiessig) Newsgroups: net.aviation Subject: Re: To Flap or Not To Flap... Message-ID: <277@idi.UUCP> Date: Sun, 17-Feb-85 18:38:18 EST Article-I.D.: idi.277 Posted: Sun Feb 17 18:38:18 1985 Date-Received: Sun, 17-Feb-85 21:41:30 EST References: <3393@alice.UUCP> <3394@alice.UUCP> Organization: Intelligent Decisions, Inc., Saratoga, CA Lines: 95 Getting back for a moment to the question at hand about high/low power/no power, here is some refresher info (paraphrased from VFR Flight Review by Avram Goldstein): 1. When abeam the numbers, reduce power from (say) 2300rpm to 1700rpm. Carb heat. 10 deg flaps, opposing nose-up tendancy with some forward yoke. You should slow from (say) 90 kts to 80 kts, and have dropped about 200 feet by the time you're ready to turn base. 2. As you turn base, add another 10 deg of flaps, again opposing the nose-up tendancy with some forward yoke. The additional drag will slow you another 10 kts - say to 70. Now you start to control your decent carefully with throttle - more if you're too low, less if you're too high. Trim if needed. 3. Apply full flaps as you turn from base to final. Try to lead this turn neatly, so taking the wind into account, so you roll out exactly in line with the runway. Many stall-spin accidents happen during this turn. If you never exceed 20 deg bank and keep the nose down at all time, it is virtually impossible to stall the airplane at approach airspeeds. But you could be distracted, then if you're not well-trimmed for a nose-down attitude, as soon as you relax pressure on the yoke, the nose goes up, the airspeed falls off, and if you are in a speep bank, you are suddenly in trouble! If you do things right, you apply full flaps as you turn final, you keep the nose down, you trim for nose-down, and you use whatever power is needed to control the decent. Your right hand should be on the throttle continuously from the moment you turn final until you taxi off the active. Your eyes should be looking over the nose the whole time. If you can't see the ground over the nose, you're in big trouble because your nose is too high and your airspeed is too low. You should glance at the airspeed indicator occasionally out of the corner of your eye. The extra drag of full flaps should slow you to (say) 65 kts on long final, and you'll lift the nose slightly on short final to 60 kts, ready for the flare. 4. At all phases of the final approach, you should concentrate on keeping the airspeed constant with a constant pitch attitude, and control your decent with power. Reducing to idle power, with full flaps, results in a very efficient decent, and if needed the decent can be increased further by slipping without a change in airspeed. My teaching has been slightly different than the book recommends: I was taught to always do one thing at a time - therefore don't apply 20 deg 1laps until you've rolled out on base. And where I fly, the downwind leg can be VERY long, resulting in a very long final (3mi or more). Therefore, I was also taught not to apply full flaps until short final, rather than on long final as the book suggests. I have always been told that putting on full flaps on base or before is VERY bad news. As the book says, many pilots get killed stalling and spinning on the turn from base to final. Bad news. Not to mention the problems of engine failure. Much better to wait until almost the last minute before putting on full flaps. This solves problems of tire/landing gear wear while at the same time keeping you safe. Suggestions of making a 180 deg turn from downwind to base or of making sharp 90 deg turns with full flaps - COME ON! If you can't make a nice-looking 90 deg turn without full flaps, or if you can't make a nice square base leg without them, watching for traffic like you should, then you shouldn't be flying! A short approach is one thing; a well- flown pattern is another. I suggest that all pilots periodically fly the pattern with no flaps. Use slips and engine control instead - which is of course what you have to do on aircraft that don't have flaps (yes, some planes don't have them!), or what you would have to do if your flaps were broken. -- Rick Kiessig {decvax, ucbvax}!sun!idi!kiessig {akgua, allegra, amd, burl, cbosgd, decwrl, dual, ihnp4}!idi!kiessig Phone: 408-996-2399