David,
Double check. Diameter is about 800 feet, level 45 degrees, at 75 KTAS.
See http://www.csgnetwork.com/aircraftturninfocalc.html
I=99m playing fast and loose with the calcs also.
Only during the turn is the altitude loss disregarded and using the now
disproven Newtonian physics, 1/2 at squared for 3 to 4 seconds is 145 to
257 feet.
Keep in mind the turn is near 90 degrees entered and exited with an
unloaded roll using every bit of the lift vector pointed to the center
of the turn maximizing rate of turn while pulling at 75 knots in the
burble of the stall. The G loading is only about 1.4 Gs by feel. The
rate of turn is outstanding as one could imagine and the radius very
small. However, if entered with any more than Zero to 1/4 G roll or
exited in the same, the altitude loss and time goes up. (Case in point:
If one attempts a 20 degree nose high, 1 G, 360 degree aileron roll, I
bet you will complete the roll 60-80 degrees nose low and in a high
speed dive.) Never do rapid loaded 1 G roll in a fast roll attempt.
Stan and I did this because it is the =9CImpossible Turn=9D.
Well that is a red flag to a bull to Stan and later I followed along so
as not to be outdone. (The ego is a terrible thing.)
I was flying in a customers aircraft (I trimmed) and just finished full
aft stick stall practice (his plane is really a nice flyer), and asked
if I could try something I hadn=99t practiced in a while. I did
the so called impossible turn at 3500 AGL to see if I could still come
close, as I hadn=99t practiced it in some time. 350 feet. Owner
tried it, a couple times and lost over a 1000 feet. He is an excellent
pilot, CFI, but not a practicing CFI any longer, current, very
comfortable in the aircraft, but not at max performance. We mused about
whether one would actually try something like that down low, and agreed
that without extensive practice and ideal conditions, it was not
sensible. But it can be done in a controlled environment.
If a turn back is attempted using normal level turn type techniques you
are right, the altitude loss is terrible. Please folks, let us not get
into a sailplane discussion here where the simulated tow rope break is
done. The Europa short wing is not a sailplane. It can roll very well,
and if straight and true, the pilot practiced, it can be flown well into
the stall. (Especially if the stall strips are placed properly.) If
one breaks into a spin during a hard turn, the plane is out of rig or
flown out of trim or side slipped by the pilot . If aileron is
introduced at any time during the stall, the down aileron will stall
first and as you well know nothing good will happen after that. Usually
a snap will occur. Back seaters would keep their knees together to keep
the tendency from trying to correct roll with aileron at the stall, the
rudder is the tool to use with a well trained foot.
These techniques are well taught in most aerobatic and out of control
recover maneuvering, also called upset training. Any load or
backpressure in a turn defeats the roll rate, aggravates the lateral
trim/rig, and can lead to a snap. If you can=99t fly into a stall
without fear, there is a reason. It is not taught any longer. The
folks that have flown with me know I am conservative, but comfortable in
the corners of the envelope. I test the aircraft here until I can fly
them without reference to the ball, only looking over the nose until the
plane is coaxed into the stall and begins to mush straight ahead. Then
I do it in harder turns. A stall is a stall. The same rules apply,
only the G loading changes. We slow flight here in gentle turns very
near the burble with confidence. Most folks do not get their plane
rigged properly. Take the time and do it. An out of rig airplane is a
snake in the grass and dangerous. Fly well away from the stall and
straight and level until you get the plane fixed. If the plane is OK and
you can=99t, then avoid the area or get some training. Even
though the information is known, without practice and confidence, the
application of the knowledge for the first time is fraught with
disaster. Knowledge is worthless without practice and currency.
As Dirty Harry said: A mans got to know his limitations. I know I try
to. My limits seem to be increasing every day I get older. Currency
and familiarity are necessary. If I am not current, I fly an airline
profile and get a lot of practice. Fly as your instructors have taught
you. Pay attention to your skills. If it feels uncomfortable,
don=99t do it until you get proper training. If your plane
can=99t get to the stall without rolling tendencies, fix it.
Be conservative when close to the ground. As I mentioned to Will, my
three mistakes altitude is about 3000 AGL but:
=9CMy personal floor is 1000 AGL now for any cruising or
maneuvering. I fly pretty much straight and level, and no more than 45
degrees of bank and do not slow below glide speed below that. Below
1000 feet you are in the
low altitude structure and that is a different discipline. Low altitude
maneuvering or military low level training were disciplines well
regulated and trained for extensively. Your time to disaster is very
short.=9D
Regards,
Bud Yerly
From: davidjoyce@doctors.org.uk
Sent: Sunday, May 01, 2016 7:57 AM
Subject: Europa-List: Turn back was SmartASS etc
Bud & William, This has the makings of a rich seam of discussion!
Firstly William, I have been a bit sloppy in talking about my stall
speed. In various formal tests for initial permit and annual renewal I
have recorded it at between 39 and 43 kts with flaps down (and 48 -50kts
clean) with loadings between 1210 and1370lbs. I have tended to do my
experiments on turn back height loss at different bank angles flying
solo so think more in terms of the lower figure, and on occasions when
the wings are polished and bug free and the wing root gaps freshly
sealed, I have recorded 38kts.
Stall speed vs Bank: The pilot's handbook for the mono XS talks of 44
kts level Max AUW stall speed. If you take that, the stall speed for
different bank angles would be: 45 Deg = 52kts; 60 deg = 62kts:
70deg = 76 kts; 80 deg = 108kts (these figures and those to
follow are available in most standard flight texts or on line at
www.csgnetwork.com). These stall speeds at 70 or 80 degree bank are
enough to persuade me that steep turns in an engine off situation are a
recipe for disaster. I once, for fun did a deliberate stall in a steep
turn (probably around 75degs) and found myself immediately in a spin.
Richard Iddon did something similar but found himself in an inverted
spin!
Turning Circles: Bud you have suggested 800ft as the diameter of turn
for at 45 degree bank will have a turn diameter of 800 ft but the actual
figure from standard tables is 445ft, and assuming that the pilot has
had the wit to turn into whatever cross wind there is, he will have
drifted much or all of this back to the centre line by the time he has
completed his 180 turn.
Height Loss: You also imply that you effectively turn the plane on its
side and let it go in free fall downwards rather than flying it in a
balanced way so maybe we are talking about something rather different.
However I have a bit of problem with your maths. You do not fall at 32
ft per sec - you accelerate downwards at 32 ft per second per second and
10 secs of free fall takes you 1600ft - not good news!
Finally can I say again that the good starting point for dealing with an
EFATO is doing just what your instructor told you - land ahead. If you
are looking to improve your skills and planning not to become the 9th
Europa pilot to succumb to a stall/spin disaster, then I would strongly
recommend working out a system of turn back that works for you and
practice it until you can do it with minimal thought
Regards, David Joyce, GXSDJ
On 2016-04-30 18:12, Bud Yerly wrote:
David,
Not to open a can of worms.
I have read the same study. In most aircraft with slow roll and high
drag, he is correct. On the average, a 45 degree bank gives a higher
turn rate and you still have 70% of your lift available to arrest your
descent.
Stan Sutterfield (another fighter pilot smart ass and Reno competitor)
and I did this in a couple of aircraft. In the Europa for instance, the
roll rate, if you unload to 1/4 G is very good (100 degrees per second).
A pull to the verge of stall near 80 or so degrees of bank at 75 KTS
(the FAA recommends 70 degrees to be the maximum of any turn of course)
, turns the aircraft at three times the rate at 75 knots. So it will
take about 3 seconds to do a 180 and the radius of turn is 200 feet.
REMEMBER, NO ATTEMPT TO MAINTAIN ALTITUDE! The average pilot needs 3
seconds to react while climbing and one second to roll in a second to
pull, and the same two seconds to roll out. That is 10 seconds from
straight ahead, to complete 180. Falling at 32.2 FPS, the plane will
drop 320 feet because gravity works 24/7. Accounting for upward
momentum during the three seconds to react at a 15 degree deck angle of
75 feet, once can see that the a completed well practiced turn can be
done in less than 300 feet. The aircraft pitch will go from 15 degrees
up to 15 degrees down and still leave you with a descent glide if done
at 800 feet and about 75 knots on completion.
The 45 degree of bank will take an agonizing 10 seconds, then add the
reaction time, and the loss of altitude in a power off turn is
staggering and the diameter of the turn is well off the centerline by
800 feet. Now you have another turn to do. That's dumb.
I have done this maniac maneuver at altitude and once in the pattern
(scared the crap out of everyone and I was at 800 feet and younger then)
and it works. (Stan did it in a 172, but he is quite skilled.) I have
had a couple of clients try it and without dedicated maneuver practice
and years of training, lost amazing altitude and buried the nose.
Without the training and practice, this is one of those bar stories and
fun things to practice three mistakes high, but totally useless. Like
racing airplanes at low altitude or doing Red Bull air racing. Fun for
the pilot, exciting to watch, but totally useless and expensive.
Besides my wife said no...
As you so wonderfully said "I do not advocate turning around in every
EFATO situation, only if you are in the situation where what lies ahead
looks as though it will kill you". is the most sage advice one can give
a fellow pilot.
NEVER DO A 180 as either it will kill you due to altitude loss or
stall, or the sudden stop will! Turn only as necessary to hit something
soft. Then open the door and step out and call the insurance company.
Best Regards,
Bud Yerly
From: davidjoyce@doctors.org.uk
Sent: Wednesday, April 27, 2016 5:19 PM
To: europa-list@matronics.com
Subject: Re: Europa-List: SmartASS my Undercarriage
Bud, excellent advice and I am envious of the F4 experience! I
hesitate to quibble but there is one point I would like to offer a view
contrary to what you appear to be saying. That is on the most efficient
way to turn in an engine out situation if you are going to turn - and I
hasten to add that I do not advocate turning around in every EFATO
situation, only if you are in the situation where what lies ahead looks
as though it will kill you, and as you say, and critically, you have
practiced all the relevant skills.
One of your countrymen , David Rogers, professor at US Naval
Academy, Indianapolis, who clearly has high order mathematical skills,
has shown definitively that the most efficient way of turning, (that is
the way of turning through any given number of degrees with minimum
height loss) is to turn at 45 degrees bank at as slow a speed as you can
sensibly maintain without falling out of the sky. Any more or any less
bank increases the height loss, quite apart from rapidly increasing
stall speed. You mentioned 80 degrees and I can imagine that this might
offer the quickest way of getting a fighter pointing in reverse, but it
would produce substantially greater height loss for an engine out
Europa, quite apart from stressing it to 5.76g and increasing the stall
speed to around 100kts, or higher if you are flying at US mauw.
My two penny (cents?) worth on stall/spin accidents, SmartASSes
and the like and a practical application of the Rogers findings, is on
the club website >>Flying>>Flight Safety, for what it is worth. If you
would like to turn your email advice into an article, I would happily
add that to this website eection.
Regards, David Joyce, GXSDJ
On 2016-04-27 06:55, Bud Yerly wrote:
William,
A distracted pilot is a link in an accident chain to be sure. Thanks
for sharing your experience. Frankly I needed it. We used to have a
safety magazine with a "There I Was" section of cartoons (with a
message) before the real there I was near mishap article someone shared.
Although I am a keep it simple kind of guy, gear warning and stall
warning systems work. Are they worth the cost, effort to install,
troubleshoot, fine tune, and test? Normally Yes.
Are slow speed voice warning systems better than the stall rumble
strips, or visual AOA systems, tones, "Bitching Bettys" and are they
worth it on a straight wing aircraft? Not to me, but they are another
tool to help cue the distracted or tired pilot to the old feeling that
something is wrong. Probably time to add a slow speed switch to 12AY.
Alas, if you get used to hearing the slow speed warning or seeing the
red AOA arrow because a system isn't calibrated, we ignore it when we
may need it the most. When something is wrong, or it doesn't feel
right, go around and get your stuff together always works. Yes, I do
carry a piddle pack and have had to use it to relieve "cockpit stress".
What's the cost of a prop, engine repair and wheel well repair vs. the
time and cost of a gear up warning system? Your choice.
What's the cost of loss of a plane/life due to a mishap caused by a non
proficient, distracted, or fatigued pilot. Priceless to us all. And
you're all lying if you haven't been there. Know you limitations.
Whether you are experience or not, practice, practice, practice. Know
your airplane, its stall characteristics, and in my case I fly it to its
limits every time I do a practice hop. I don't do touch and goes. I do
very low approaches where I slow flight down the runway for a 1000 feet
just inches from the runway, perfectly aligned and it makes me keep
flying the airplane rather than that old relaxation on landing habit we
fall into, and my touchdowns are at 45 instead of 50. (My tires don't
wear out either.) Don't put yourself into situations where you are
overly fatigued. (No more afternoon takeoffs and long three hops to get
home, as I have a credit card and am not afraid to use it at any hotel.)
Never take anything for granted, use the checklist, know your pitch,
power settings and speeds. Become a student of aviation again, take
the time to read (Google just about any topic and you get a wealth of
info, try "pitch and power flying"). We do things as old (read as
experienced) aviators from muscle memory, but the brain muscle is the
most important tool, and we have to sharpen a tool to use it
effectively.
Develop good habits by breaking old ones. Read articles again on flying
and techniques to get the brain juices flowing again. The Rotax and
Airmaster have made me a lazy pilot. It is easy to push the power
forward and pull the stick back and the houses get smaller, but it is
power that makes us climb, not pitch alone (for long anyway) and
occasionally I wish I had my GIB (Guy In Back in the F-4) to tell me to
"Start doing some of that pilot SH T and get us out of here." or the
famous "Doesn't all that shaking and beeping and rudder pedal vibration
bother you?" as he locks his knees together at high AOA to prevent a
departure from controlled flight.
Practice routinely, know your airplane well, know the proper site
pictures, pitch and power settings and install rumble strips on the
leading edge to allow the aircraft feel to warn you of an approach to
the stall. Then set and calibrate your EFIS/Stall Warn/AOA system to
warn of a low speed situation/gear up or accelerated stall in the turn
to keep you honest when you're not having your best day. Practice
simulated engine out approaches, no flaps, partial power situations.
Develop a passenger brief. Practice an emergency ground egress as if
you just departed the runway and found one of our Florida water filled
ditches and need to get unstrapped and out quickly. Climb up three
mistakes high and do power on and off stalls. Practice unload for
control drills. The plane won't stall if the AOA is zero. (Unload for
control is an old military drill where the aircraft is flown to a high
pitch attitude and the aircraft is unloaded to a quarter G (just getting
light in the seat, not negative) and allowing the plane to fall
through.) It teaches what an unload feels like when you are in need of
full power instant acceleration to get out of trouble at slow speed
rather than the push the stick forward drills I see our local
instructors do. What happens when at 75 knots in a full power climb and
you pull the power, count to three (reaction time) and try to do a 180.
I've done a 180 in less than a couple hundred feet, but 80 degrees of
bank pulling at the burble is not a recommended thing to do, can I do
it, yes, will I do it rather than go for the golf course, no. If I goof
it up, I'll get killed, if I hit a tree and land in it or hit a sand
trap, I'll survive. Stretch a glide by slowing to near stall speed and
watching the VSI, then do it at 75 and note the difference. Pull the
power to idle on base and glide at best glide speed and see how your
pattern is affected. Then do practice engine out approaches. Bottom
line, If I haven't flown in thirty days, I go practice much of the
above. If I haven't flown in 60 days, I fly with an instructor if I can
find one, and if I can't, I go with another current experienced pilot
and or take it in baby steps to get the pitch and power down, checklist
operations, air work, emergency procedures and finally landings, at
least three. Normal low approaches to get the feel of the pattern, then
a normal full flap touch and go, no flap touch and go, full stop, min
roll takeoff and soft field landing.
All the FARs in the US say is to fly alone, I can go nearly 24 months
(last BFR) if I want and then do three takeoffs and landings and I can
take folks up with me on a cross country (DUH).
My two cents,
Trying to live longer.
Bud Yerly
-----Original Message----- From: William Bliss Sent: Tuesday, April 26,
2016 4:37 PM
Subject: Europa-List: SmartASS my Undercarriage
Hi All
Just thought I would tell you how I had long flight last weekend.
Arriving back at the farm strip aching for a pee I had to do a low pass
to clear the sheep. That quickly done, downwind checks and on finals
sizing up the crosswind I became aware of a voice telling me to check I
had the wheel down. I had not got the locking catch properly in place.
Sorted. I would say the investment in the SmartASS has paid off....
William Bliss G-WUFF
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