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How did the BV 141 fly? It looks like it has very uneven weight distribution and the overall design is asymmetric. I'm surprised that it could even take off.

this is a picture of the BV-141

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    $\begingroup$ See also: en.wikipedia.org/wiki/Rutan_Boomerang $\endgroup$ – casey Sep 28 '15 at 20:42
  • $\begingroup$ Curious that the horizontal stab is so truncated on the right side. Why would the do that? $\endgroup$ – Ralph J Sep 28 '15 at 21:30
  • $\begingroup$ The weight from the cockpit on the right is balanced by adding weight with one horizontal stabilizer on the right and no horizontal stabilizer on the left. $\endgroup$ – Ethan Sep 29 '15 at 1:29
  • $\begingroup$ More than the weight of the cockpit, I think it's positioned that way to avoid turbulence from the cockpit. If you have clean air on one side of the aircraft why not use it? The imbalance due to the down-force being off-center doesn't matter as much as you'd think. $\endgroup$ – slebetman Sep 29 '15 at 9:15
  • $\begingroup$ @RalphJ: To improve the field of view and to give the rear gunner less of a chance to disable his own aircraft. $\endgroup$ – Peter Kämpf Sep 29 '15 at 16:15
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Why would you think the weight was not correctly distributed? If the center of pressure and the center of gravity coincide, there is no problem. Every pilot needs to bring the center of pressure right above or below the center of gravity when flying; this is commonly known as trimming the aircraft. Almost all aircraft have small asymmetries which need to be counteracted by small control surface deflections or trim tab settings.

Note that the fuselage of the BV-141 is offset to the left and the cockpit is offset to the right. This keeps the spanwise center of gravity location near the center of the wing, so any resulting rolling moment is small. What remains (maybe due to an unusual high or low loading of the cockpit) can be trimmed away with the ailerons. A yawing moment due to asymmetric thrust can also be corrected by rudder trim, and the engine was placed on the left so the p-factor of the propeller (which creates more yawing moment at low speed) would counteract the yawing moment due to its out-of-center position.

The BV-141 was designed as an observer platform with an unrivaled field of vision. By using an offset fuselage, only the left side was obstructed by an engine or tailboom. If you compare the BV-141 with its competitor for the same tender, the Focke-Wulf 189, the advantage should become obvious.

Focke-Wulf Fw-189

Focke-Wulf Fw-189 (picture source)

Note that the BV-141 was a private entry in this contest and was not selected.

A similar aircraft with an asymmetrical mass distribution was the Flyer I of the Wright Brothers. Here, the right wing was 4 inches wider than the left to create additional lift for the heavy engine which was positioned to the right of the pilot.

Front view of the 1903 Flyer I

Front view of the 1903 Flyer I (picture source). Note the offset engine position.

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  • $\begingroup$ Thank you for not only answering the given question, but the unwritten one, "why in the heck would they do that???", as well! $\endgroup$ – FreeMan Sep 29 '15 at 15:26

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