Symmetry is over rated

Kinja'd!!! "Cé hé sin" (michael-m-mouse)
09/19/2017 at 16:48 • Filed to: Blohm und Voss, BV 141, Planelopnik

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Meet the Blohm und Voss BV 141.

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Yes, it’s all there . No bits have fallen off or been forgotten. What’s more, twenty were built. More would have been, but the BMW 801 engine it used was in demand elsewhere.

You want to see one flying, don’t you? Of course you do.

Naturally, the late !!!error: Indecipherable SUB-paragraph formatting!!! flew one because of course he did. He flew everything.

Blohm und Voss no longer make planes, even symmetrical ones, but they will get you !!!error: Indecipherable SUB-paragraph formatting!!! . Their former air division wound up in Airbus along with much of the German aerospace industry.


DISCUSSION (14)


Kinja'd!!! user314 > Cé hé sin
09/19/2017 at 17:01

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What was it with B&V? Besides the 141, they had proposed three other asymmetrical aircraft to the RLM, though none of the others made it past the concept stage.

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Kinja'd!!! Cé hé sin > user314
09/19/2017 at 17:03

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They just though quite a long way outside the box!


Kinja'd!!! user314 > user314
09/19/2017 at 17:09

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Forgot the P.202 scissor wing.

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Kinja'd!!! ttyymmnn > Cé hé sin
09/19/2017 at 17:13

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Burt Rutan agrees.


Kinja'd!!! Cé hé sin > ttyymmnn
09/19/2017 at 17:17

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So it seems.

I’ve haven’t been able to find out why B & V’s designer liked asymmetry. Interestingly, he worked for Boeing after the war, but symmetrically.


Kinja'd!!! Mondial goes to 11 > Cé hé sin
09/19/2017 at 17:39

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This isn’t a perspective trick. A DC-3 with a DC-2 wing.


Kinja'd!!! kanadanmajava1 > Cé hé sin
09/19/2017 at 19:10

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Some of the symmetric B&V designs very also “out of the box” type of ideas.

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Kinja'd!!! TheRealBicycleBuck > Cé hé sin
09/19/2017 at 19:48

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I have to wonder about additional yaw introduced by it being assymmetric. I imagine that it would want to rotate one way or the other depending on the throttle setting.


Kinja'd!!! gmporschenut also a fan of hondas > Cé hé sin
09/19/2017 at 20:56

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Blohm and voss were so crazy. the 238 had wing turrets!

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Kinja'd!!! BaconSandwich is tasty. > kanadanmajava1
09/19/2017 at 22:02

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That last one reminds me of the companion cubes in Portal 2 that start getting more and more messed up.


Kinja'd!!! BaconSandwich is tasty. > TheRealBicycleBuck
09/19/2017 at 22:03

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I was wondering about that as well. What would the advantage be?


Kinja'd!!! Cé hé sin > BaconSandwich is tasty.
09/20/2017 at 05:24

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The design provided a fully glazed rear cockpit - the plane was intended for observation.


Kinja'd!!! Cé hé sin > TheRealBicycleBuck
09/20/2017 at 05:28

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I’ve been wondering about that. On the face of it, the plane would seem to want to travel only clockwise, with one slightly offcentre engine pushing to the right and the drag from the offcentre cockpit reinforcing that. In fact it flew perfectly well. You’d think that RC builders would like to give it a go and they have.

There’s also a better film of the real thing here:


Kinja'd!!! TheRealBicycleBuck > Cé hé sin
09/20/2017 at 08:54

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I did a little googling and found more video of an R/C plane with a little more information. From the description:

“At first glance, the placement of weight would have induced tendency to roll, but the weight was evenly supported by lift from the wings. In terms of thrust vs drag asymmetry, the countering of induced yaw was a more complicated matter. At low airspeed, it was calculated to be mostly alleviated because of a phenomenon known as P-factor , while at normal airspeed it proved to be easily controlled with trimming.” 

What is really odd to me is the tendency to yaw left on take-off. I saw it in the videos of the full-size plane and again in the video of the R/C plane. It’s something I’ve experienced when flying with friends, but I thought the asymmetric design would alleviate that problem. I found a great explanation here: http://www.boldmethod.com/learn-to-fly/aerodynamics/why-you-need-right-rudder-on-takeoff-to-stay-on-centerline/

I see this as a really interesting design for FPV and R/C mapping applications. Providing separation between the power pod and the observation pod should make packaging the equipment much easier and may reduce some of the vibration experienced by the camera gear.