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I'm asking about functional asymmetry - doors on one side but not the other wouldn't count.

Examples

I can think of three examples:

  • experiments with oblique wing designs, such as NASA's utterly hideous AD-1, designed apparently by Burt Rutan
  • displaced fuselage designs, such as the Blohm & Voss BV 141 or (another Burt Rutan aircraft), the Boomerang
  • all single-propeller aircraft, in which the torque of the engine exerts asymmetrical forces on the aircraft

Symmetrical asymmetry doesn't count

(Then there are some that I don't think really count - for example, the Wright brothers' Flyer 1 placed the engine and the pilot side-by-side, but since they were intended to balance each other out and the twin propellors were symmetrically placed, that counts as an attempt at symmetry as far as I am concerned!)

Other examples, and the reason for their asymmetrical design

Are there any other good examples? The more ugly and wrong-looking, the better.

I'm interested in the problems that the asymmetry aimed to solve - for example, oblique wing designs aimed to procure aerodynamic advantages (which turned out to be at the expense of handling issues), or Rutan's Boomerang which "was intended to be a multi-engine aircraft that in the event of failure of a single engine would not become dangerously difficult to control due to asymmetric thrust" (Wikipedia)

Visual reference

Just for reference, here's the AD-1 (NASA, via Wikipedia):

NASA AD-1

... and the BV 141 (Deutsche Bundesarchiv, via Wikipedia):

Blohm & Voss BV 141

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    $\begingroup$ Burt Rutan's Boomerang is asymmetrical, but I wouldn't call it ugly. $\endgroup$
    – Dan Pichelman
    Aug 31, 2016 at 18:03
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    $\begingroup$ 747 with a spare engine mounted... $\endgroup$
    – DJohnM
    Aug 31, 2016 at 19:14
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    $\begingroup$ The Wright Flyer's wing was 4 inches wider on the side of the engine, because the Wrights wanted to compensate for the heavy engine. Wouldn't that count as a functional asymmetry? $\endgroup$
    – Peter Kämpf
    Sep 1, 2016 at 4:06
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    $\begingroup$ Don't be silly, why would anyone make an assym... oooh... I learned a thing today! $\endgroup$
    – Dewi Morgan
    Sep 1, 2016 at 5:10
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    $\begingroup$ there are many GA aircraft that have an asymmetrical engine mount and/or an asymmetrical empannage to counter P-factor. $\endgroup$
    – rbp
    Sep 1, 2016 at 22:55

5 Answers 5

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There are quite a few asymmetric aircraft, most of which are,

  • experimental

  • engine test beds

A good example of experimental aircraft is the NASA F-16XL

F-16XL

F-16XL with supersonic laminar flow control experiment (black area on left wing, front) or "glove." Image from nasa.gov

Aircraft used as engine test beds are usually asymmetric. The following image shows a B-47 Stratojet used as engine test bed for the the Orenda engine earmarked for Avro Arrow program.

B-47

Image from silverhawkauthor.com

A closeup of the rear:

B-47

Image from google

English Electric Canberra PR9s had offset canopies.

Canberra PR9

By MilborneOne - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=13266605

So did the de Havilland Sea Vixens.

Sea Vixen

By Yeovilton_Vixen_2009-001.tif: Nigel Ishderivative work: Cobatfor - This file was derived from  Yeovilton Vixen 2009-001.tif: , CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=19477903

Of course, all 'conventional' helicopters (with tail rotors on one side) are asymmetric, but I don't think that's what you're after here.

Also, see this page and the Wikipedia page on asymmetric aircraft. As a disclaimer, I wouldn't call any of these aircraft 'ugly'.

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    $\begingroup$ I have never seen or heard of most of these aircraft! This is fascinating. +1 for the great question and +1 for this great answer. $\endgroup$
    – Steve
    Sep 1, 2016 at 1:24
  • $\begingroup$ The Orenda ingests the boundary layer of the wing in the configuration used on the B-47! What were they thinking? This is no way to conduct proper testing. $\endgroup$
    – Peter Kämpf
    Sep 1, 2016 at 8:09
  • $\begingroup$ If we count aircraft with offset parts then there are probably more aircraft than one might expect. Even the A-10 has an offset nose landing gear in order to accommodate the gun.c1.staticflickr.com/9/8722/16696627519_9142f36d14_b.jpg $\endgroup$
    – DeepSpace
    Sep 1, 2016 at 8:58
  • $\begingroup$ The observer in the Sea Vixen was positioned under the hatch to the right of the offset cockpit canopy; this was a frangible hatch where the ejection seat would shatter the hatch in the event of an ejection. Unfortunately, it was not always as frangible as it should have been. $\endgroup$
    – Peter Smith
    Oct 10, 2019 at 10:43
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All aircraft with external storage that dump only one become instantly asymmetrical. A particularly extreme example might be the Heinkel He-111 H22, which was designed to carry a V1 to a launching point in order to attack targets beyond the reach of the fixed launch catapults, or the B-52 used to carry the X-15 aloft.

Heinkel He-111 H22 with FZG-76

Heinkel He-111 H22 with FZG-76 (picture source)

Even after dropping the cruise missile, the He-111 H remained an asymmetrical configuration, because the tip of its glazed nose was offset to one side, so the front gunner would obstruct the pilot's view less.

Inside view of the He-111 cockpit

Inside view of the He-111 cockpit (picture source).

B-52 just after launch of the X-15

B-52 just after launch of the X-15 (picture source)

Also here the aircraft remained asymmetrical after having launched the X-15 due to the large pylon used for carrying the X-15.

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Another Rutan design (I think his earliest asymmetric) was the Ares "mudfighter" with a 25mm cannon on one side of the cockpit, and the turbojet air intake on the other. The design was intended to keep the pressure waves and nasty combustion gasses from the cannon from being ingested by the engine.

The NASA X-15 Active wasn't asymmetric by design, but was designed to induce asymmetries (to simulate failures, or damage, up to and including loss of an entire wing).

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The M.C.202 actually had wings of different sizes to compensate the engine/propeller rotation:

As rightfully requested, here are some pictures from the video:

M.C.202 from top

M.C. 202 from bottom, mirrored left wing

M.C. 202 from bottom, difference made clear

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    $\begingroup$ Many fighter aircraft of that period had cambered vertical tails to help to counter torque effects. This is also a functional asymmetry. $\endgroup$
    – Peter Kämpf
    Sep 3, 2016 at 21:02
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The Rutan Voyager (World Flight, 1986) two wings are not at the same position along the length of the aircraft. To save weight, their non-tapered spars are bolted together in the fuselage, so one wing is one spar thickness ahead of the other. With a wingspan of over 100 feet, it isn't very noticeable.

It also has two vertical stabilizers but only the starboard one has a movable rudder. To cut down on questions about that, they put a line on the port one that looks like a rudder gap using an ink marker (lighter than paint!). Lower cruise drag and weight at the cost of terrible rudder performance asymmetry (right rudder response was fine; left rudder response almost nonexistent).

This learned from conversations with Dick Rutan, the Voyager's pilot, in 1985/1986.

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