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09-24-2020, 11:50 AM
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Join Date: Feb 2005
Location: LSGY
Posts: 3,198
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webinar
Very good webinar - the best I've seen on the "impossible turn". One thing I learned from it is to not fly an underpowered aircraft!  You just need to be able to climb faster than your glide speed, stay awake in case something happens to your engine during climbout, and get the nose down.
Gotta admit, some of my climbs are a bit shallow trying to make sure I don't get CHTs over 400, but I'm certainly going to take into account what I learned in this webinar, and run the test cards they suggest. I'm in "test card" mode anyway, so not a problem.
Avoiding a straight out departure also seems to be a pretty easy way to reduce risk.
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09-24-2020, 12:00 PM
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Join Date: May 2012
Location: Ga
Posts: 662
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Assume engine out
Every takeoff it is assumed engine out, unless proven otherwise.
It’s going to quit, one day. I assume it will be today and I’m focused and ready. So ready that sometimes a bit disappointed it doesn’t quit. Kinda weird but those who train and train and train sometimes deep down would like to see the real thing, but at some time, not want to see the real thing. Hard to explain.
For my -9, I’m at pattern altitude a little past half way down the runway and so I have more margins and options. All that hp and prop is my margin maker at takeoff.
Engine out in the twin is either a VMC rollover or crash straight ahead unless you clean it up VERY fast. Blue line means nothing in the Aerostar with both flaps and gear down.
Assume the worst and stay focused and tell your passenger to hush up while you are in the cone of danger.
__________________
Craig
RV-3 Sold
RV-4 Sold
RV-6a Sold
RV-9 IO-360 CS, Built and Flying
Aerostar 600A, Family Hotrod
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09-24-2020, 03:06 PM
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Join Date: Nov 2018
Location: Peachtree City, GA
Posts: 121
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After reading a few articles on the subject I have changed from climbing out at VY to VX...I'm usually solo and I can climb decently. I have practiced the 180 and feel that at 500' agl I can do the 180 plus have 100' to manuever ...but that's if I know its coming, so realistically 600' would be my personal decision height.
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09-24-2020, 04:07 PM
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Join Date: Jan 2017
Location: White Salmon, WA
Posts: 173
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Quote:
Originally Posted by donaziza
To posters 13 and 21. I'm at zero flaps on the takeoff. As I'm bending the airplane around in that 270* turn, to get back to the airport, I'm running out my flaps to lower my stall speed, so I don't stall and die. (At 45* bank, I'm gonna stall with no flaps, and I'm at max bank trying to get back to the runway) ) The airport is right there----behind me. To leave the flaps up---well Ok, sure, but that would mean I'm high enough above the airport, that I can afford the luxury of having a higher stall speed, and more time to glide back, ie, I'm farther away. Understand?
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No, I don’t understand. Best glide speed for our aircraft is well above stall. In this maneuver, the objective is to get back to the runway. Running out the flaps will always work against you in this case. Once you are assured of making the runway, or have picked a landing point, deploying the flaps at that point is a standard emergency checklist item. If you’re worried about stalling in the maneuver, and you should be, just don’t stall.
__________________
Steve Morrow
RV-12 N12SM
Builder 121036
White Salmon, WA
2020 Donation Paid
Last edited by Tacco : 09-25-2020 at 10:40 AM.
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09-24-2020, 04:21 PM
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Join Date: Aug 2010
Location: Brookshire, TX
Posts: 1,036
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Quote:
Originally Posted by Captain Avgas
+1 Exactly. Turning through approximately 180 degrees without engine power is hardly a high risk aerobatic manoeuvre. But like all emergency manoeuvres it is MUCH more likely to be successfully executed by a pilot who is proficient in the technique. Forced off field landings...stall recovery...turnback at take-off...you don't want to be attempting any of these things for the first time in a real emergency. Practice makes perfect.
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nods
I'm glad that I had in instructor who first demonstrated, and then had me fly, real-world turnbacks. This was during my initial tailwheel training, in a Citabria...we did them from 350'.
I'm glad we did this not because now I "know how to do them," but rather because I now know that it's a very intimidating maneuver. It's not hard at all to imagine how someone trying this for the first time under stress might react poorly and kill themselves.
I maintain that the maneuver is not inherently impossible - rather, the impossibility comes from people who believe they can "rise to the occasion" and try out a whole new flight regime in a do-or-die situation.
__________________
Philip
-8 fuselage in progress (remember when I thought the wing kit had a lot of parts? HAHAHAHAHA)
http://rv.squawk1200.net
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09-24-2020, 04:29 PM
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Join Date: Aug 2005
Location: Atlanta, GA
Posts: 4,218
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Quote:
Originally Posted by Tacco
No, I don’t understand. Best glide speed for our aircraft is well above stall. In this maneuver, the objective is to get back to the runway.
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In my world, the objective is to put the airplane down somewhere relatively flat that won't hurt me or the passengers. A runway would be nice, but the grass near the runway would be fine too and much better than stalling it into a bunch of trees. A chainlink fence isn't a bad thing to hit once you're on the ground. There's some give and lots of deceleration.
__________________
Kyle Boatright
Marietta, GA
2001 RV-6 N46KB
2019(?) RV-10
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09-24-2020, 04:49 PM
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Join Date: Feb 2005
Location: Zurich, Switzerland
Posts: 466
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Our SOP is to always climb the first 400-500ft at vx/70kts and then accelerate to 85+.... gets you through the "danger zone" the quickest/steepest (before obstacles) way possible, I believe.
The options then literally improve with every additional 100ft gained...
On our aircraft (RV7A, IO360/180hp, Hartzell cs prop) this also means neutral pitch trim and very little inputs required to maintain attitude with most other than very aft c.g. conditions (slight nose down trim needed then). The transition to that attitude however stuns many passengers as the resulting deck angle gets really quite high ;-)
Of course this angle initially frightens when you think about engine failure... And frankly in many less agile aircraft types this might be an issue.
I did however quite a few "simulated" engine failures at altitude from exactly this attitude and from full takeoff power setting during test flying.
The good news is that the moment the propwash vanishes from the tail, the nose comes down quite easily without excessive input required and it doesn't need as much of a push as you would imagine (although a little) to go from climb to descent and increase speed to best glide 85kts+.
I highly recommend to practice this with your own aircraft as "getting it right" is really quite important for any next steps... Otherwise you either loose too much altitude and go overspeed or you end up with underspeed and high descent rate and with the nose too high.
Having transition trained with Jan Bussell in Florida on his -6A, he "swam against the flow" by instructing and focusing quite a bit on the "impossible turn" despite the common reservations against.
I found this honestly quite enlightening, even though it definitely shouldn't be the first choice of action.
He demonstrated it with as little as 600ft altitude loss including somewhat of an alignment, my comfort zone would be more like 700+ft for a "simple" 180° and 1000ft+ to realign with a runway/airport area. Also, this was flight training with the engine never actually stopped...
In all cases you end up quite a bit downwind and initially offset from the point of liftoff. But that may be a field instead of bad obstacles or buildings.
So it is very helpful to know the surroundings and adapt your plans accordingly.
By the way, Jan taught flaps out only ever well through the turn / when landing / wings level was assured. Speed 90kts+ for much of the turn and an immediate but steady bank angle of about 45-50° if I remember right. Maybe someone else also trained with him and has a better description of his method?
__________________
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Bernie Daenzer, Alex Lichtensteiger
www.flyvans.com
RV-7A
S/N 72072, Flying!
HB-YMT (Switzerland)
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09-24-2020, 04:51 PM
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Join Date: Jan 2005
Posts: 959
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Quote:
Originally Posted by Kyle Boatright
A chainlink fence isn't a bad thing to hit once you're on the ground. There's some give and lots of deceleration.
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Probably. But note that there have been sailplane pilots who have been decapitated when landing off-field and gone through barbed wire fences. The wire slices through the canopy. Tip-ups would be more vulnerable to this than say, the RV-8 slider with its stout roll bar in front of the pilot.
As a glider pilot (and former CFI-G & DPE), simulated rope breaks with a 180* turn back and landing are done in training. I'm glad for that experience, as much of the drill does carryover to power flying (with different parameters, of course).
Last edited by RV8JD : 09-25-2020 at 01:21 PM.
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09-24-2020, 06:49 PM
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Join Date: Jan 2005
Location: Cincinnati, OH
Posts: 1,558
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The webinar was very eye-opening. The main takeaway I got was the analysis that showed the glide line versus the climb angle. If you are not above that best glide angle on climb out, there’s no way you will make it back to the airport in a turn back. There aren’t a lot of airplanes that can do that in standard ISA conditions. Our RV’s are usually an exception, conditions not withstanding, but training in this maneuver is important. A complete power loss during this critical phase of flight is a life or death situation, and the possible dire consequences are immediately in your face. Practicing this beforehand, many times, will help to make the response more automatic. There is no cookie cutter solution here for our RV’s. Every airplane is different. A constant speed prop makes a very noticeable difference, as does gross weight, CG, and density altitude. The three airplanes I built all had constant speed props. My current RV4, which I didn’t build, has a fixed pitch prop. The difference with a complete loss of thrust is dramatic. When we practiced this in the airlines with a complete loss of power during a high energy climb (a Sully aftermath), it required a fairly rapid reduction in pitch, to the extent that we “became light in the seat” as they called it. In my fixed pitch RV4, it’s way less dramatic. In fact, if I’m in trim on takeoff, and lose thrust, I really only need to release any back pressure to completely unload the wing, which should result in zero G loading. It’s impossible to stall a wing at zero G. It’s the same situation with a constant speed prop, but the pitch change and descent rate is greater. Practicing this is important for your airplane with varying gross weights and atmospheric conditions.
I read a controversial idea in one of the magazines a short time ago, addressing this subject. It was determined with testing, that if you turned downwind after takeoff to get a 10-30 degree downwind track (more in lighter winds, less in stronger crosswinds), a turn back after power loss - into the wind, resulted in lower altitude loss, due to tighter turn radius relative to ground track, and closer alignment with the departure runway for the emergency landing. Makes sense to me. I haven’t tried it yet. Probably only applicable at uncontrolled airports.
Whatever you do, you need to think about it and maybe brief yourself before takeoff, so when the unexpected happens, even though you are surprised, you’ll know exactly what to do. Pick an altitude, pick a spot. Those two critical decisions are already made. Now just fly the plane.
This is easy to talk about, not so easy to successfully accomplish. Training is the key, and you can do this training solo. I’ve done it.... but I haven’t done it enough.
__________________
SH
RV6/2001 built/sold 2005
RV8 Fastback/2008 built/sold 2015
RV4/bought 2016/sold/2017
RV8/2018 built/Sold(sadly)
RV4/bought 2019 Flying
Cincinnati, OH/KHAO
JAN2020
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09-25-2020, 01:04 AM
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Join Date: Feb 2017
Location: Australia
Posts: 615
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For me personally a turn back is my absolute last choice, just too many variables to make it the number one priority.
My 8 climbs like a homesick Angel I don't touch the gas pedal till I'm thru a grand, that takes very little time.
There is so many gotcha's in a turn back. Forget the aerodynamics of it for a moment. Obstructions, terrain, Rwy length, WIND, other traffic, overrun at the other end & rushed decisions. I'd rather trim for min glide speed and put down straight ahead +|- a few degrees.
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