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Old Oct 03, 2008, 02:06 PM
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Toronto,Canada
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Jim,

Quote:
Originally Posted by jbourke
As for how to fly a plane with one wing, consider that the remaining wing has a lot of drag so it would be very hard to fly knife edge with the wing on the bottom. Putting the wing on the top helps the plane stay in knife edge. I consciously chose to put the wing on top and keep it there.
Not knowing much about aerodynamics, why would top vs bottom make a difference?

So how different did the plane "feel" compared to flying KE with two wings?

Do you think it would be even possible to take-off with one wing? With the 3d "monster power-weight ratio, as is common these days, maybe a "burst of power" with elevator would be enough to get it in the air, and then quickly transition to knife edge. ?

Mike
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Old Oct 03, 2008, 02:29 PM
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United States, OR, Corvallis
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Quote:
Originally Posted by Mike Stramba
Not knowing much about aerodynamics, why would top vs bottom make a difference?
I don't think I can adequately explain it here, but basically anything that moves through the air produces drag against the movement. For a plane to fly in knife edge, it must be angled with the nose away from the ground. This is easier to do if the drag from the wing is helping, rather than hurting, that effort. The wing can only help if it is pointed straight up.

Quote:
So how different did the plane "feel" compared to flying KE with two wings?
It wanted to roll left, so I had to hold right aileron. It wanted to yaw left, so I needed right rudder. It wanted to pitch down, so I needed up elevator.

It was not at all like flying normal knife edge. A properly trimmed airplane will fly knife edge almost on its own. A little bit of rudder is all that is needed.

Quote:
Do you think it would be even possible to take-off with one wing? With the 3d "monster power-weight ratio, as is common these days, maybe a "burst of power" with elevator would be enough to get it in the air, and then quickly transition to knife edge. ?
That would be very difficult. The challenge is that during the initial acceleration there isn't enough airspeed over the control surfaces to overcome all the imbalanced forces. The plane is highly unstable in any orientation other than knife edge.

Also, I wouldn't want to have the engine anywhere near full RPM with the plane in this configuration!

Jim
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Old Oct 03, 2008, 04:33 PM
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Toronto,Canada
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Quote:
Originally Posted by jbourke
For a plane to fly in knife edge, it must be angled with the nose away from the ground. This is easier to do if the drag from the wing is helping, rather than hurting, that effort.
Ahh, ok, I get it now.

Quote:
Originally Posted by jbourke
It wanted to roll left, so I had to hold right aileron. It wanted to yaw left, so I needed right rudder. It wanted to pitch down, so I needed down elevator.

It was not at all like flying normal knife edge. A properly trimmed airplane will fly knife edge almost on its own. A little bit of rudder is all that is needed.
Cool ! .. thx for the insight.

Quote:
Originally Posted by jbourke
That would be very difficult. The challenge is that during the initial acceleration there isn't enough airspeed over the control surfaces to overcome all the imbalanced forces. The plane is highly unstable in any orientation other than knife edge.

Also, I wouldn't want to have the engine anywhere near full RPM with the plane in this configuration!

Jim
Oh, c'mon, throw together a cheap electric foamy, and cut off one wing.

You know you want to try it

Mike
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Old Oct 04, 2008, 06:25 PM
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Joined Dec 1996
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Wow. I've already watched that video about 20 times and I smile every time. Is Keith going to fix it again or simply replace the model?

I hope to spend some of my 2008 Christmas bonus (yes, we get an extra month's salary here) on Real Flight. Will the program by then have a setting with Keith's one-wing Yak? And maybe get some BCRCC members lined up some day and record them yelling "Way to go!" so to imbed additional sound effects.
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Old Oct 04, 2008, 06:49 PM
outstanding in the left field!
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USA, IL, Marengo
Joined Feb 2007
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Fly the pieces

Beautiful work. Bet you could do that again! Maybe a part of your new airshow act the one wing yak attack. You could practice a few one wing tricks and just fly around a bit more next time? Brings a new meaning to the phrase "fly the pieces"

Pyro
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Old Oct 05, 2008, 04:00 AM
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Quote:
Originally Posted by jbourke
I don't see any reason why the plane would prefer one roll orientation over another. The drag caused by the remaining wing imparts yaw only, assuming the plane is neutrally stable to begin with. Yak-54s have nice round fuselages and mid-wings, so they are about as neutral as you get. Of course, in the real world each axis is only in balance with all the pieces in place, so losing a wing will impart some amount of roll in some direction. That doesn't mean that the plane will stop with the wing up or down, though. Most likely it would just keep on rolling.

As for how to fly a plane with one wing, consider that the remaining wing has a lot of drag so it would be very hard to fly knife edge with the wing on the bottom. Putting the wing on the top helps the plane stay in knife edge. I consciously chose to put the wing on top and keep it there.

Holding the plane in knife edge and guiding it around required pressure on all three axes. By that, I mean that left on its own, it wanted to roll, pitch, and yaw. Finding the center position needed to keep the plane stable was really the only trick to the flight.

Understand that I only have about a minute of real-world experience with this. We can watch the video over and over, but in real time it all happened very quickly.

My thought process was something like "Let me try a snap roll at high speed...oh, hey, the wing fell off...let's see if I can find a control center to keep it stable...looks like that keeps it in knife edge...I'll try turning it...looks like pitch and roll are coupled...I'll just coax it around to my right...keep the airspeed the same and bring it down in the pattern...I'll just put it over here in the grass...hmmm...I bet I can land it...I'll try rolling it level and see what happens...ok, back to knife edge...and now let me give it a shot...hey it worked!"

If you read that while you watch the video you'll have a sense of what I experienced, and you can see that there isn't much time to learn about this flight regime. However, I have played with it a lot on RealFlight, mostly because I kept getting confronted by people who thought this behavior was unrealistic in the sim. It turns out that RealFlight has it correct, and I was only able to do this in real life because the sim prepared me for it.

Jim
Jim ,
Me and my son have flown enough cheap foam gliders to know when the wing falls off the remaining wing always points up. Flying rather well also.
Good Save!
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Old Oct 05, 2008, 05:55 PM
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Awesome save jim, check this out!

http://www.youtube.com/watch?v=xprTl6cPdH0
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Old Oct 07, 2008, 12:45 PM
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Incredible ! Way to go !

Paul
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Old Oct 08, 2008, 04:36 PM
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I'm sad I missed all the fun, show up for chili and end up witnessing an amazing feat. As if your inverted pylon racing skills weren't already a great endorsement of RealFlight.
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Old Oct 08, 2008, 10:54 PM
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I could have landed that with NO WINGS!
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Old Oct 09, 2008, 03:20 AM
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Epic!!!
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Old Oct 09, 2008, 04:01 PM
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I know RIGHT!
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Old Oct 11, 2008, 09:25 AM
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Quote:
Originally Posted by jbourke
I don't see any reason why the plane would prefer one roll orientation over another.
Well, once a wing is lost, the plane will still need some positive AOA to fly. In this setup apart from the drag considerations from the remaining wing, the wing that is left will tend to weathervane in the airstream. This will tend to make the plane stabler in KE when the wing that is left is kept pointing upward, it might well be impossible to do any maneuvering with the wing pointing downward. Any pitch (yaw now?) will tend to get the plane rolling through 180 degrees
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Old Oct 11, 2008, 04:39 PM
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Adelaide,South Australia
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golden!- one of the best videos ive ever seen in RC flying!

great composure and flying JB.

can you post the video as download-able?

i want to save it to my hard drive to show and email to others.

what was especially impressive is that you also landed it on the runway!!

nice.

Tim
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Old Oct 11, 2008, 05:02 PM
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Quote:
Originally Posted by what_the?!
golden!- one of the best videos ive ever seen in RC flying!

great composure and flying JB.

can you post the video as download-able?

i want to save it to my hard drive to show and email to others.

what was especially impressive is that you also landed it on the runway!!

nice.

Tim
http://youtubedownload.altervista.org
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