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Ed Cesnalis

in the air, before its ready to fly

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That looked more like a gust of wind got under their wing and blew them over.

Put that stick towards the crosswind on takeoff and use that rudder to hold it on the centerline! As soon as the airplane gets light on the wheels, a crosswind is going to try to roll it over!

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Yeah, the crosswind was a big factor and he needed to correct for this.  He immediately begins to sink after drifting off the runway.  He just didn't have enough speed to give his tail needed authority to fight the Xwind and didn't have enough speed to remain in the air.

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I'm looking at the picture-in-picture. It looks like the MOMENT he lifted, that wind got under the right wing, pushed the tail over, and the tail contacted the ground. From there I think they just paniced trying to get higher.

CTs are an aircraft where they can be in a stalled state, yet still have pitch authority. I showed a new instructor the other day. I could hold the nose up, showed them that I still had control authority, but we were descending rapidly. This is that "mushing" effect.

I am a little bit confused in regards to what you mean by the enough speed for the tail to fight the crosswind. For me personally, in serious crosswinds in a CT, I will have so much aileron in that it's going to jump up on one wheel towards the crosswind, and that relieves a lot of rudder pressure.

image.png.9c70e64ffd8fccef6c054a2d05845e03.png

I've taken off and landed in winds well in excess of 20 knots (even gusts over 30), and this is the only way to safely do it when it develops into stiff crosswinds.

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He does get blown off the runway to the left by Xwind  but if you look at the video both from the cockpit and from the vacitioner's video, you see the nose is high due to his response as I probably would have done which is to try keep from sinking by pulling his nose up.  This only makes matters worse due to his low airspeed.  He also is trying to get back to the runway.  He was off the ground sufficient to not crash with nothing but sagebrush.  If he would have kept the nose low to the ground and not attempted to get back to the runway, he might have allowed the speed to build and might have eventually gained enough speed to keep flying.  Elevated altitude and low density altitude.  The runway was going by probably above 60kts or better but his airspeed would have been below this and too low to provide lift needed for taking off so soon into his departure at this density altitude.

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16 hours ago, WmInce said:

Underscores the risk of making downwind takeoffs . . . especially during gusty conditions.

100% agree.  Downwind takeoffs and landings are dangerous.  Under certain conditions (long runway, no gusts, uphill landing and/or poor approach in the other direction) I have accepted a 1-2kt tailwind on landing.  It's always surprising how much even a tiny tailwind costs in landing distance.

Anything more than the above conditions is really playing with fire.

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My preferred grass strip is very steep, so my tailwind practices are obviously different than the typical flat runway situation.  Just observing that this is all situation dependent.

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I would rather accept a 5-8 Kt. tailwind and have a clean approach rather than a landing over high trees or wires. On take off I am happy to live with even a strong tail wind, I just raise the nose a little and let it fly off when it's ready then stay in ground effect till enough speed is reached. It is safer not to look at the ASI and feel when the plane is ready to fly not force it to try to climb. The visual clues we are used to all go out the window with a tail wind.

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If I remember this accident correctly the wind was a right quartering 25K +/_ tailwind. Watch the blowing dust after impact. This would be a difficult situation for an experienced pilot to handle with no room for error. In this case the pilot was relatively inexperienced.

I think injuries were minor which says a lot about the CT.

At the time the pilot/owner was going to hang up his wings. Does anyone know if he changed his mind? I hope he did.

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On 10/9/2021 at 8:47 PM, ct9000 said:

I would rather accept a 5-8 Kt. tailwind and have a clean approach rather than a landing over high trees or wires. On take off I am happy to live with even a strong tail wind, I just raise the nose a little and let it fly off when it's ready then stay in ground effect till enough speed is reached. It is safer not to look at the ASI and feel when the plane is ready to fly not force it to try to climb. The visual clues we are used to all go out the window with a tail wind.

ct9000, Exactly.  Takeoffs with tailwinds can be SOP provided there's sufficient runway length.  The pilot should keep the nose light with some back-pressure on the stick.  This results is the pilot letting the plane rise off the runway - the plane lets the pilot know when it's time to fly.  USE DUE DILIGENCE FOR REQUIRED RUNWAY LENGTH!  As Andy says, a small trailing wind greatly increases the length of runway needed.  Add to this required runway length if taking off with any or all of the conditions:  high altitudes, low  pressure altitudes and loading of the aircraft.   I occasionally do trailing wind takeoffs to remain proficient doing this should the need arise.  For landing with tail winds, I also practice doing this with different flap settings.  First, I determine what airspeed I need to provide a good sink to the runway during low wind conditions.  This gives me a target airspeed to trim for during the tailwind landing.  Do not use external sight when landing but use the target airspeed to provide a base for landing. Practicing tail wind landings the first few times, it is alarming how fast the ground is going by.  Prevent this surprise from happening if a tailwind landing is needed by practicing this procedure.

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On 10/9/2021 at 8:47 PM, ct9000 said:

I would rather accept a 5-8 Kt. tailwind and have a clean approach rather than a landing over high trees or wires. On take off I am happy to live with even a strong tail wind, I just raise the nose a little and let it fly off when it's ready then stay in ground effect till enough speed is reached. It is safer not to look at the ASI and feel when the plane is ready to fly not force it to try to climb. The visual clues we are used to all go out the window with a tail wind.

I would respectfully disagree.  IMO, if you have enough runway to accept a 8kt tailwind, you have *way* more than enough to get the airplane down over any reasonable obstacle.  The CT slips very well, and with full flaps (or even 30°) it comes down like an elevator.

My standard approach at 30° is around 48kt.  With an 8kt tailwind that means my actual ground speed is 56kt.  With a 8kt headwind ground speed is 40kt...that's a 16kt swing.

At 40kt ground speed you are traveling about 67 feet per second.  At 56kt ground speed you are traveling around 94 feet per second.  Assuming it takes five seconds from the end of the runway to touch down, at 40kt you land 335ft from the end of the runway, at 56kt it's 470ft.  If you get your speed wrong and it takes ten seconds to touch down, the numbers become 670ft and 940ft respectively...on a 2000ft runway you are almost halfway down at 56kt ground speed.

Unless the runway is *really* short, you don't really have to worry about trees and wires.  Just manage your descent rate to pick up once you are clear of the obstacles.  When I am right over the trees I start my slip if needed, and since I'm past the obstacle there is no worry.  Probably half of my landings are made this way, I fly out of a lot of strips tucked in the trees.  I have posted this before, but here's a landing over 80ft trees onto a 1200ft grass strip with about a 7kt headwind:

 

Also, remember that the difference in ground speed equates to much higher energy with a tailwind.  That means if there is an incident or loss of directional control after touchdown, the amount of energy to be dissipated is much higher.  But it's only 16kt, you say?  Well, that equates to 1.96x the energy of the lower speed.  Yes, almost double.  Energy is (mass times velocity squared), which means small changes in speed make huge changes in energy state of the airplane.

I'm not saying you have to fly your airplane my way, you are your own pilot.  I'm just letting you know the thought process that's behind it.  Personally, I'd rather screw up an approach and be in the trees at 40kt than on the runway and flip the airplane at 56kt, even on grass.  YMMV.

 

 

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On 10/9/2021 at 8:47 PM, ct9000 said:

. . . . . It is safer not to look at the ASI and feel when the plane is ready to fly not force it to try to climb. The visual clues we are used to all go out the window with a tail wind.

The two statements above seem like a paradox.

I have to disagree there. Regardless of the wind, the airspeed indicator will not lie to you. What's more, the airplane does not care about the surface wind condition . . . it only cares about the relative wind coming off the nose. Disregarding airspeed (eyes only out front and flying by the seat of the pants) is setting oneself up for an unanticipated and unwanted event. Indicated airspeed should never be disregarded during landing or takeoff.

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1 hour ago, WmInce said:

The two statements above seem like a paradox.

I have to disagree there. Regardless of the wind, the airspeed indicator will not lie to you. What's more, the airplane does not care about the surface wind condition . . . it only cares about the relative wind coming off the nose. Disregarding airspeed (eyes only out front and flying by the seat of the pants) is setting oneself up for an unanticipated and unwanted event. Indicated airspeed should never be disregarded during landing or takeoff.

We had this discussion the other night, and I'm kind of between these two lines of thinking.  I'm usually Looking mostly outside...I check to confirm proper RPM, and that airspeed is climbing.  Usually by the time I get to the ASI on the takeoff roll I'm at around 40kt, which is close to flying speed, and then I'm looking entirely outside.  Airspeed is of course critical, but I also think in these small, light airplanes that keeping your eyes outside is also critical.  It's very easy for a CT to wander or lose direction, and you want to be on top of that ASAP.   As long as the airspeed is building you can just add a little back pressure and the airplane will fly when ready.  The main things are to stay on the pedals to maintain direction, and make sure you don't force the airplane off before it's ready with too much aft stick.

I understand both perspectives on this, and I somewhat split the difference.  But I think I tend more toward the "eyes outside" takeoff.  In a larger airplane where there is less direct feedback and more ground stability (face it, CTs are twitchy on the ground!), watching the ASI is probably a better bet.

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