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)
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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.
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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
>
>
>
>
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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
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Subject: | Re: 180 turn back to the runway video |
....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
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Subject: | Re: 180 turn back to the runway video |
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
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Subject: | Re: 180 turn back to the runway video |
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
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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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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
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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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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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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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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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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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