Kolb-List Digest Archive

Thu 04/29/10


Total Messages Posted: 13



Today's Message Index:
----------------------
 
     1. 01:21 AM - Re: Angle of Bank vs Stall Speed (Dana Hague)
     2. 03:25 AM - Re: Angle of Bank vs Stall Speed (robert bean)
     3. 03:50 AM - Re: Angle of Bank vs Stall Speed (Jack B. Hart)
     4. 05:50 AM - Re: 180 turn back to the runway video (Thom Riddle)
     5. 05:56 AM - Re: 180 turn back to the runway video (Thom Riddle)
     6. 07:43 AM - Re: 180 turn back to the runway video (Jason Omelchuck)
     7. 09:55 AM - Re: Re: BNC bulkhead connector (Jmmy Hankinson)
     8. 10:49 AM - Angle of Bank vs Stall Speed (The Kuffels)
     9. 01:21 PM - Re: 180 turn bact to the runway video (Arksey@aol.com)
    10. 02:56 PM - Re: Angle of Bank vs Stall Speed (Jack B. Hart)
    11. 05:00 PM - Re: Re: 180 turn back to the runway video (b young)
    12. 09:30 PM - Re: Angle of Bank vs Stall Speed (The Kuffels)
    13. 10:08 PM - Re: Angle of Bank vs Stall Speed/Approach Technique (The Kuffels)
 
 
 


Message 1


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    Time: 01:21:37 AM PST US
    From: Dana Hague <d-m-hague@comcast.net>
    Subject: Re: Angle of Bank vs Stall Speed
    At 04:39 PM 4/28/2010, The Kuffels wrote: >For more details as to why this is true review my messages in the thread >linked by Jason: > >http://forums.matronics.com/viewtopic.php?t=38477&highlight=descending+turn+stall I did. I stand by what I said there, as well as in this thread. ><< In a coordinated turn, the stall speed increases as a function of the >bank angle >> Correct. >true *if you maintain (approximately) a >constant vertical component for your lift vector.* The only way to do this >is to increase your total lift, in other words maintain constant altitude, >in other words increase your load factor. Correct. Note that if you don't maintain "a constant vertical vertical component for your lift vector", you will accelerate downward (or upward, as the case may be, though that's not what we're talking about). >...This is the case of a constant >airspeed in a turn. Some of the lift is now used to make the turn and less >lift is available to oppose gravity and you will *start* to descend faster. >But since the total lift is unchanged so is the stall speed. In other >words, stall speed increases with load factor, not angle of bank. Correct. "You will *start* to descend faster." And if you maintain 1G in a banked turn, you will *continue* to accelerate downward. ><< Take a 45 degree bank, for example. In a normal, coordinated, level >turn, you pull 1.41G. If you put your aircraft into a 45 degree bank and >hold 1G, the vertical component of lift will be only 0.707g; thus you'll >have a downward acceleration of 0.3g, or 9.4 ft/s/s, or 566 fpm/s. This >means that after one second, your rate of descent will have increased by 566 >fpm. After four seconds, you're descending at 2264 fpm, which is a pretty >steep dive, and you WILL pull more than one g pulling out of it. >> > >The math here is wrong. After one second you are descending at 9 feet/sec, >2 seconds you are now at 19 ft/sec, 3 seconds = 28 ft/sec, 4 sec = 38 ft/sec >or so. In addition it ignores the vertical component of drag which is >significant. What math do you say is wrong? Sounds like you're agreeing with me, as I said after one second you're descending at 9.4 ft/s, etc. You rounded the numbers off but they're approximately the same as mine (after four seconds, 38 ft/s is 2280 fpm). The vertical component of drag is zero at the start, and then yes, it becomes significant. However, it doesn't affect the math, because regardless of the drag, you _have_ to accelerate downward as described above or you won't maintain 1G. >...Half way through the turn they see they are >overshooting the runway. What they should do is increase their angle of >bank to 45 degrees or even briefly 60 degrees at constant airspeed to finish >the turn. Instead, because "increased angle of bank means increased stall >speed" (in a different context) has been fixated in their minds they try to >fudge the situation with rudder and/or tightening up (pulling on the stick) >instead... Both are the wrong thing to do. Increase the bank angle in coordinated turn and you risk an acelerated stall; add rudder for a skidding turn and you risk stalling the inside wing. >What we must fixate instead is >"constant airspeed = constant load factor = constant stall speed". Constant load factor = constant stall speed, yes. Constant airspeed has nothing to do with it. Don't get me wrong; i understand (or I think I understand) the technique you're advocating: steepen the turn but don't pull back, instead letting the airplane fall off into a descent. But saying that you're OK if you maintain a constant airspeed is fixating on one aspect of the problem, and can get a pilot into trouble. Fly at 1.3Vs and enter a 60 degree coordinated turn and you either get an accelerated stall, or end up in a dive which also requires more than 1G to pull out. "But don't believe me," do the math yourself. -Dana P.S. A conventional pitot tube airspeed indicator is only accurate when the pitot tube is aligned with the airflow. At high AOA, the airspeed indicator will read less than the actual airspeed, i.e. you're actually going faster than you think you are... which may explain why you're not stalling even when the indicated airspeed is less than the stall speed corresponding to the load factor corresponding to the bank angle. "But don't believe me," do the math yourself. -- Life is a sexually transmitted disease.


    Message 2


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    Time: 03:25:19 AM PST US
    From: robert bean <slyck@frontiernet.net>
    Subject: Re: Angle of Bank vs Stall Speed
    Good stuff Tom. Can't say I've studiously done exactly what you describe but sounds 100%. In my younger and bolder days, on occasion I used a method to bleed altitude that I would not recommend: not S turning, not slipping, not the Kolb dive... I would, on a high final, deliberately stall the old crate, or pretty close to it. Sure would lose a lot of altitude and the wings would stay nice and level. Then I'd toss a touch of throttle at it and squeak it on nice and short. Obviously this would be solo. Gusty conditions would be a no no, as would hedgerows or any extraneous turbulizers. Very exhilarating. Last time I did it for funsies was on a near zero day in a field near where a neighbor was operating a McCulloch J2 gyrocopter. I siloed it a touch too aggressively and bent a few tubes and cracked the windshield. It needed a new one anyway. Only landing I did that short after that was with a power failure in a neighbor's champ on take off with nothing good ahead. (wires and houses) Silo descent to plowed ground aside the runway. Zero roll out. No damage. Old neighbor never asked me to fly his areoplane again though. I wouldn't try it in my Kolb. Too old. Back might break. BB On 28, Apr 2010, at 4:39 PM, The Kuffels wrote: > Sent this two hours ago. So far it hasn't appeared on the list. My paranoid side says there must be censorship of my ideas somewhere. > > ----------------------------------------------------------------- > > Sigh. My conscience won't let me ignore this. > > pj, boyd, Dana: > > Dang it, ignore what I say, fly the maneuver and see for yourself. Go to > altitude, reduce power if you wish, enter a 30 degree bank and hold > absolutely constant airspeed for 180 degrees and then roll level. Repeat at > 5 miles/knots slower. Repeat again until you are as close to Vso as your > ability to hold a constant airspeed allows. You will not stall. > > For more details as to why this is true review my messages in the thread > linked by Jason: > > http://forums.matronics.com/viewtopic.php?t=38477&highlight=descending +turn+stall > > Now: > > << If the turns are less than 30 deg and the g load less than 1.5,, you > may be ok. if the turn is 60 or more deg bank and g load 2 or above >> > > << In a coordinated turn, the stall speed increases as a function of the > bank angle >> > > These out of context statements are exactly the misconception which kills > pilots every year. I know, it almost killed me during my primary training. > I know, base to final turn accidents are a major source of aircraft > fatalities every year. They are true *if you maintain (approximately) a > constant vertical component for your lift vector.* The only way to do this > is to increase your total lift, in other words maintain constant altitude, > in other words increase your load factor. > > But don't believe me, go out and fly the maneuver yourself at altitude. > > Look at the AIM diagram we have all had drummed into our subconscious. As > the angle of bank increases, the total lift increases to keep the vertical > component the same. Now with your hands block out all but the first > airplane. Rotate the entire manual. This is the case of a constant > airspeed in a turn. Some of the lift is now used to make the turn and less > lift is available to oppose gravity and you will *start* to descend faster. > But since the total lift is unchanged so is the stall speed. In other > words, stall speed increases with load factor, not angle of bank. > > But don't believe me, go out and fly the maneuver yourself at altitude. > > << Take a 45 degree bank, for example. In a normal, coordinated, level > turn, you pull 1.41G. If you put your aircraft into a 45 degree bank and > hold 1G, the vertical component of lift will be only 0.707g; thus you'll > have a downward acceleration of 0.3g, or 9.4 ft/s/s, or 566 fpm/s. This > means that after one second, your rate of descent will have increased by 566 > fpm. After four seconds, you're descending at 2264 fpm, which is a pretty > steep dive, and you WILL pull more than one g pulling out of it. >> > > The math here is wrong. After one second you are descending at 9 feet/sec, > 2 seconds you are now at 19 ft/sec, 3 seconds = 28 ft/sec, 4 sec = 38 ft/sec > or so. In addition it ignores the vertical component of drag which is > significant. > > But don't believe me, go out and fly the maneuver yourself at altitude. > > The above statements as well as the "death spiral" of Boyd's CFI are the > result of misunderstanding the context of what I and others are trying to > fix. The problem is the turn from base to final. Most pilots initiate a > bank of about 30 degrees. Half way through the turn they see they are > overshooting the runway. What they should do is increase their angle of > bank to 45 degrees or even briefly 60 degrees at constant airspeed to finish > the turn. Instead, because "increased angle of bank means increased stall > speed" (in a different context) has been fixated in their minds they try to > fudge the situation with rudder and/or tightening up (pulling on the stick) > instead. This brings them to experience the other four fundamentals of > flight: stall, spin, crash and burn. What we must fixate instead is > "constant airspeed = constant load factor = constant stall speed". > > But don't believe me, go out and fly the maneuver yourself at altitude. > > Now just because I have an evil nature let me mention one more context > besides turns at low altitude for landing. This should start another thread > in the Seafoam mode. The concept of constant airspeed control is also > paramount in mountain search and rescue reversing turns and box canyon > escapes. What I teach is no change in power, smoothly increase your climb > rate and bank until you reach your desired bank and airspeed, say Vs1 + 10. > Maintain this bank and airspeed until you have reversed direction. You will > now be in a decent but at a higher altitude, smoothly pullout and you are > now going in the opposite direction at roughly your starting altitude and > airspeed. This method allows the pilot to concentrate on airspeed control > and situational awareness without the distraction of power control. The > reduced airspeed during the turn also creates a very small radius of turn. > > But don't believe me, go out and fly the maneuver yourself at altitude. > > Let me finish with an irrelevant appeal to authority. Every, and I mean > every, CFI with whom I've had the above discussion and then taken flying has > adopted my emphasis on constant airspeed control for maneuvering close to > the ground. > > But don't believe me, go out and fly the maneuver yourself at altitude. > > Good luck and have fun, > > Tom Kuffel, CFI > EAA Flight Advisor > > > >


    Message 3


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    Time: 03:50:58 AM PST US
    From: "Jack B. Hart" <jbhart@onlyinternet.net>
    Subject: Re: Angle of Bank vs Stall Speed
    From: "The Kuffels" <kuffel@cyberport.net> > Sigh. My conscience won't let me ignore this. ......... > Tom, Sounds like you are advocating flying a powered aircraft much like flying a glider or sailplane. Sailplane instructors emphasize coordinated turns and constant speed and never mention constant altitude. When I started flying sailplanes, one of the things I had to unlearn was the desire to maintain altitude through out a turn, and learn to fly at constant speed. You are correct in that I never fell into a spin while thermalling while flying at constant speed no matter how steep the bank or the speed. With an engine as the energy source, one can easily recover any altitude lost after a constant speed turn. I believe it is a less stressful way to fly on both the pilot and the machine, since one does not have make power changes during a turn to maintain constant altitude. Thanks. Jack B. Hart FF004 Winchester, IN


    Message 4


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    Time: 05:50:14 AM PST US
    Subject: Re: 180 turn back to the runway video
    From: "Thom Riddle" <riddletr@gmail.com>
    ....Here is a very good video about the "Impossible Turn" as performed by two guys in a C172. http://www.aerobats.com/seminar_02-07.html Richard Pike MKIII N420P (420ldPoops)..... Richard, Thanks for posting the "impossible turn" video. Very good indeed. It was missing only two things to complete the picture. An AOA gauge and and G-meter. -------- Thom Riddle Buffalo, NY Kolb Slingshot SS-021 Jabiru 2200A #1574 Tennessee Prop 64x32 An ounce of action is worth a ton of theory. - Friedrich Engels Read this topic online here: http://forums.matronics.com/viewtopic.php?p=296119#296119


    Message 5


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    Time: 05:56:36 AM PST US
    Subject: Re: 180 turn back to the runway video
    From: "Thom Riddle" <riddletr@gmail.com>
    Ooops! Actually there is a third thing missing in this video. The engine was running at idle power. With idle power the relative effects of various degrees of bank on turn time and altitude loss are correct but what is missing is the effect of stopped prop. But still a very good informative video.... just not complete. -------- Thom Riddle Buffalo, NY Kolb Slingshot SS-021 Jabiru 2200A #1574 Tennessee Prop 64x32 An ounce of action is worth a ton of theory. - Friedrich Engels Read this topic online here: http://forums.matronics.com/viewtopic.php?p=296126#296126


    Message 6


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    Time: 07:43:42 AM PST US
    Subject: Re: 180 turn back to the runway video
    From: "Jason Omelchuck" <jason@trek-tech.com>
    Hello Tom, I have a clutch on my engine so the prop windmills (and my airplane behaves) with the engine at idle just like it would with the engine stopped. Regards Jason Thom Riddle wrote: > Ooops! > > Actually there is a third thing missing in this video. The engine was running at idle power. With idle power the relative effects of various degrees of bank on turn time and altitude loss are correct but what is missing is the effect of stopped prop. But still a very good informative video.... just not complete. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=296141#296141


    Message 7


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    Time: 09:55:15 AM PST US
    From: "Jmmy Hankinson" <jhankin@planters.net>
    Subject: Re: BNC bulkhead connector
    Thanks for the reply's on the BNC connector I was looking for. The one I wanted was the one that went through the floor of my Firefly to attach a external antenna to my radio. Only use my radio to listen to air traffic. Do not have a tower airport near me. Ones near me are Savannah and Augusta Georgia. I am halfway between each one. Sixty miles each way. Thanks again for the help. Do Nor Archive Jimmy Hankinson Firefly N6007L Georgia


    Message 8


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    Time: 10:49:03 AM PST US
    From: "The Kuffels" <kuffel@cyberport.net>
    Subject: Angle of Bank vs Stall Speed
    Sigh. My conscience won't let me ignore this. pj, boyd, Dana: Dang it, ignore what I say, fly the maneuver and see for yourself. Go to altitude, reduce power if you wish, enter a 30 degree bank and hold absolutely constant airspeed for 180 degrees and then roll level. Repeat at 5 miles/knots slower. Repeat again until you are as close to Vso as your ability to hold a constant airspeed allows. You will not stall. For more details as to why this is true review my messages in the thread linked by Jason: http://forums.matronics.com/viewtopic.php?t=38477&highlight=descending+turn+stall Now: << If the turns are less than 30 deg and the g load less than 1.5,, you may be ok. if the turn is 60 or more deg bank and g load 2 or above >> << In a coordinated turn, the stall speed increases as a function of the bank angle >> These out of context statements are exactly the misconception which kills pilots every year. I know, it almost killed me during my primary training. I know, base to final turn accidents are a major source of aircraft fatalities every year. They are true *if you maintain (approximately) a constant vertical component for your lift vector.* The only way to do this is to increase your total lift, in other words maintain constant altitude, in other words increase your load factor. But don't believe me, go out and fly the maneuver yourself at altitude. Look at the AIM diagram we have all had drummed into our subconscious. As the angle of bank increases, the total lift increases to keep the vertical component the same. Now with your hands block out all but the first airplane. Rotate the entire manual. This is the case of a constant airspeed in a turn. Some of the lift is now used to make the turn and less lift is available to oppose gravity and you will *start* to descend faster. But since the total lift is unchanged so is the stall speed. In other words, stall speed increases with load factor, not angle of bank. But don't believe me, go out and fly the maneuver yourself at altitude. << Take a 45 degree bank, for example. In a normal, coordinated, level turn, you pull 1.41G. If you put your aircraft into a 45 degree bank and hold 1G, the vertical component of lift will be only 0.707g; thus you'll have a downward acceleration of 0.3g, or 9.4 ft/s/s, or 566 fpm/s. This means that after one second, your rate of descent will have increased by 566 fpm. After four seconds, you're descending at 2264 fpm, which is a pretty steep dive, and you WILL pull more than one g pulling out of it. >> The math here is wrong. After one second you are descending at 9 feet/sec, 2 seconds you are now at 19 ft/sec, 3 seconds = 28 ft/sec, 4 sec = 38 ft/sec or so. In addition it ignores the vertical component of drag which is significant. But don't believe me, go out and fly the maneuver yourself at altitude. The above statements as well as the "death spiral" of Boyd's CFI are the result of misunderstanding the context of what I and others are trying to fix. The problem is the turn from base to final. Most pilots initiate a bank of about 30 degrees. Half way through the turn they see they are overshooting the runway. What they should do is increase their angle of bank to 45 degrees or even briefly 60 degrees at constant airspeed to finish the turn. Instead, because "increased angle of bank means increased stall speed" (in a different context) has been fixated in their minds they try to fudge the situation with rudder and/or tightening up (pulling on the stick) instead. This brings them to experience the other four fundamentals of flight: stall, spin, crash and burn. What we must fixate instead is "constant airspeed = constant load factor = constant stall speed". But don't believe me, go out and fly the maneuver yourself at altitude. Now just because I have an evil nature let me mention one more context besides turns at low altitude for landing. This should start another thread in the Seafoam mode. The concept of constant airspeed control is also paramount in mountain search and rescue reversing turns and box canyon escapes. What I teach is no change in power, smoothly increase your climb rate and bank until you reach your desired bank and airspeed, say Vs1 + 10. Maintain this bank and airspeed until you have reversed direction. You will now be in a decent but at a higher altitude, smoothly pullout and you are now going in the opposite direction at roughly your starting altitude and airspeed. This method allows the pilot to concentrate on airspeed control and situational awareness without the distraction of power control. The reduced airspeed during the turn also creates a very small radius of turn. But don't believe me, go out and fly the maneuver yourself at altitude. Let me finish with an irrelevant appeal to authority. Every, and I mean every, CFI with whom I've had the above discussion and then taken flying has adopted my emphasis on constant airspeed control for maneuvering close to the ground. But don't believe me, go out and fly the maneuver yourself at altitude. Good luck and have fun, Tom Kuffel, CFI EAA Flight Advisor


    Message 9


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    Time: 01:21:41 PM PST US
    From: Arksey@aol.com
    Subject: Re: 180 turn bact to the runway video
    Hi gang, in regard to this subject....when I was young and before I had soloed in a J-3 I had a world war ll navy pilot for a instructor....he seemed to understand what a teenager might have in mind....we were quite high and he had me do a circle using a house with a big porch as a point to circle around....he said for me to imagine my girl friend standing on the porch in a swimming suit waving at me, he had me do a steep bank and keep bringing the stick back to keep the girl in sight all the time and adding more top rudder to keep from losing altitude, I forgot what we did with the power setting but am sure is was cruise or wide open, I will never forget what happened.....we stalled very abruptly and the plane went over the top and down into a very tight spin....was very impressive......after solo I am sure I buzzed some girl friends house's but never made that mistake....just thought you might find this piece of old history of interest....not sure how a kolb would react...jswan do not archive jim swan firestar ll 503 michigan


    Message 10


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    Time: 02:56:10 PM PST US
    From: "Jack B. Hart" <jbhart@onlyinternet.net>
    Subject: Re: Angle of Bank vs Stall Speed
    Kolbers, Viewed Richard Pike's recommended video yesterday evening. For those of you with out a high speed Internet connection, I recorded the data, and here it is. C 172 flying at a constant 65 ias making full 360 degree coordinated turns. Bank Lost Decent Angle Altitude Rate (deg) (feet) (fpm) 15 879 600 30 450 650 45 390 900 60 350 1500 The video displayed the instrument panel. The rate of decent did not increase during the turn. The stall horn came on during the 45 degree bank but there was no buffeting. There was some buffeting during the 60 degree bank, but no stall horn. Also the performed some 180 emergency turn arounds by setting their altimeter to zero at 100 feet agl. They flew the airport runway at 100 ft agl and initiated a climb at over the runway and climbed to 600 feet agl and pulled the throttle. They could not get back to the airport using a 15 degree bank. Good video! Jack B. Hart FF004 Winchester, IN


    Message 11


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    Time: 05:00:25 PM PST US
    From: "b young" <by0ung@brigham.net>
    Subject: Re: 180 turn back to the runway video
    Tom and the gang: Ok I don't think we are really that far apart. What I think we need now is a definition of terms. Example: is a 1 g turn anything between .7 and 1.3 or .8 and 1.2...... give me your definition of 1 g maneuver. I had given an example of a steep bank turn to emphasize the situation. And my definition of 1 g plus is 1.01g and above. I am probably taking things to literally. Any time you turn a plane there is going to be more energy required. And you can trade the energy needed to turn by unloading the wings momentarily and remain at a literal 1g . But as soon as the plane returns to a steady state and you remain in a turn, greater than 1g will be required. In a shallow bank turn it may be as small as 1.05g total. In my definition that is 1 plus g. If that is a 1 g maneuver by your definition, then we are still on the same page. When given the terms power off descending turn. It left the parameters a bit too open. Now I had mentioned that I had not seen the video. So maybe everyone else had a better idea of the parameters used. Sorry if I misled anyone. Boyd Young


    Message 12


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    Time: 09:30:13 PM PST US
    From: "The Kuffels" <kuffel@cyberport.net>
    Subject: Re: Angle of Bank vs Stall Speed
    Dana said: << << In a coordinated turn, the stall speed increases as a function of the bank angle >> Correct. >> Not correct. This is only true in the special circumstance of maintaining altitude, ie increasing total lift, aka load factor. The emphasis on this without equal emphasis on the special circumstance is *why* pilots in the stress of landing still stall by trying to increase their rate of turn with rudder alone (uncoordinated flight) and/or pulling back (increasing load factor). The certain antidote to this error is constant airspeed during landing maneuvers. Once again, go up in the air and test my statements. I don't dispute holding a constant airspeed in a turn will increase your rate of decent. But we are not talking about turns which last for minutes or even more than a few seconds. I strongly dispute the notion that any technique other than constant airspeed and coordinated flight independent of (less than aerobatic) bank angle is the proper way to avoid problems during the turn from base to final, particularly in situations of no or steady power or practicing same, which should be almost always. Boyd said: << I had given an example of a steep bank turn to emphasize the situation. And my definition of 1 g plus is 1.01g and above. I am probably taking things to literally. >> Not really. I wasn't worried about 1 g +/- 10% or so. The problem is the emphasis on bank angle materially increasing stall speed (I call double a material increase) without equal emphasis that the real cause is via increased load factor, and that this doesn't apply in a descending turn has resulted in pilots killing themselves year after year in the turn to final. And the absolutely, positively sure way to not increase load factor in this turn is constant airspeed. << Any time you turn a plane there is going to be more energy required. And you can trade the energy needed to turn by unloading the wings momentarily and remain at a literal 1g . But as soon as the plane returns to a steady state and you remain in a turn, greater than 1g will be required. >> This is not true. The lift vector on the wings has no idea what the gravity vector is doing. Go up and set a bank angle of 20 degrees and constant airspeed. You will find yourself in a steady state turn of 1 g. What will also happen is your rate of decent will increase. But this decent is not in a vacuum. The increase in your decent is actually slowed by the air such that several full circles are easily possible.. I've demonstrated this many times for people, even disbelieving fellow CFIs. (Are CFIs really people?) Now when doing the same thing at 60 degree bank things get real exciting very soon, even at only 1/4 circle, which may be Dana's point. But my point is this fact doesn't apply to the problem, its cause or the proper solution to avoid it. Tom Kuffel


    Message 13


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    Time: 10:08:33 PM PST US
    From: "The Kuffels" <kuffel@cyberport.net>
    Subject: Re: Angle of Bank vs Stall Speed/Approach Technique
    Robert, << I would, on a high final, deliberately stall the old crate, or pretty close to it. Sure would lose a lot of altitude and the wings would stay nice and level. Then I'd toss a touch of throttle at it and squeak it on nice and short. >> A slight variation of this is very common when landing on short, no go-around strips like in the mountains. The difference is choose a speed slightly higher than Vso but lower than normal. And return to normal approach speed before touchdown. By flying within this back side of the power required curve you can greatly change your approach point without drastic maneuvers by simply modulating your speed. It is counter intuitive to shorten your touchdown point by slowing down (raising the nose slightly) and lengthen by speeding up (lowering the nose slightly) but is quickly mastered. This is much easier on passengers' nerves than a sideslip and easier to judge than S-turns. Relating to prior discussions, this airspeed changing is done only on final after the last turn is over. Hesitate to mention but for really short strips a related but different and risky procedure is required. Get level with your touchdown point. (These strips seem to always be on the sides or tops of mountains so level approach is possible. If not, get as close to level as you can.) Put the airplane as close to stall as you dare. Control altitude with lots of engine power. When you get to the strip threshold smoothly reduce or cut the power as required and plop down the final, hopefully less than 6, inches. For a Kolb can't think of a strip where this extreme technique is necessary. But try the first technique, initially with lots of margin, then closer to maximum. Even us old fuddy-duddies can use it safely if we don't wait too long to return to normal approach over the threshold. Tom Kuffel




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