Could This Change Air Travel Forever?

Bilateral symmetry is an unspoken assumption in aircraft design. Anything in nature that flies, from the smallest insect to the largest bird, possesses symmetry. But birds don't fly supersonic.

In the 1950’s Robert Thomas Jones, a brilliant NASA engineer, began developing a radical new wing arrangement called an oblique wing (also referred to as a skewed wing). The wing design was characterized by a wing that could pivot into a unique angled configuration in relation to the aircraft’s fuselage. The design offered several advantages over more conventional swept wings. An oblique wing’s ability to pivot into a straight wing made it ideal for low speed flight (improving efficiency and take-off/landing performance), but at transonic and supersonic speeds, the angled orientation minimized both wave and induced drag, leading to improved overall aerodynamic efficiency. With lower drag at higher speeds, oblique wing aircraft would require less thrust to maintain a given speed, resulting in reduced fuel consumption and operating costs. Compared to other variable geometry wings, oblique wings would also be lighter, less complex and have fewer drawbacks like a shifting center of lift.

Jones proved his theories through wind tunnel tests and with small scale remote control models. Promising results prompted NASA to undertake more intensive research during the 1970s. The first major step was the propeller-driven Oblique Wing Remotely Piloted Research Aircraft (OWRPRA) which first took flight in 1976. At the same time, aviation leaders Boeing and Lockheed were invited to study oblique wings to assess their benefits to commercial air travel. In 1979 the NASA Ames-Dryden-1 (AD-1), a subsonic, human piloted oblique wing aircraft began rigorous flight testing.

NASA’s research efforts validated many of Jones’s theories, and the oblique wing demonstrated promise in real world flight. There were plans to follow the subsonic AD-1 program with a supersonic testing program using a modified U.S Navy F-8 fighter, but the program was cancelled early on in development. Budget constraints and shifting priorities have largely stalled intensive oblique wing research programs since the early 1990s. There are still widespread reservations about the flying qualities of highly asymmetrical aircraft. Flight control at extreme wing pivots is unfavorable and requires automated systems to augment flight control. Using modern flight control technologies and advanced materials, many of these drawbacks could be overcome. Oblique wings are still considered a viable concept for large transports and many are convinced that they will eventually be adopted. The advantages are simply too great to ignore.

[bobkrausen]

An excellent summary of the history and milestones of the oblique wing program! I was fortunate to be working at Ames Industrial Corp when the AD-1 was being built. Burt Rutan did the detail design, Ames did the fabricating. Funny side-story: the government contracting guy thought he was releasing funding for an UNMANNED model aircraft due to the low cost of the was not of course. A colleague, Ron S., who has sadly passed on, was the primary fabricator with a group of us supporting manpower requirements as needed. I participated in some of the larger structure layups for the wing and fuselage as well as in the load testing of the wing before final aircraft assembly. Good times. The aircraft was constructed in our Ames facility in Bohemia, NY and we towed the finished AD-1 (using my pickup as a tug) about 1 mile to the nearby McArthur Airport where a National Guard C-130 was waiting to whisk the AD-1 off to NASA Ames in California (no "Ames" relation) for final inspection and flight testing. During construction two designated NASA pilots would fly from NASA Ames to McArthur and visit our facility for custom cockpit "fitments". One NASA pilot, Tom McMurtry, was an especially tall dude so we had to make sure he could fit and function in the tiny cockpit. The aircraft now resides in the Hiller Aviation Museum in San Carlos CA. If you remove the fuselage cover just forward of the wing pivot you'll find the signatures of the team who designed, built, and flew the AD-1, my signature is among them. I have some pictures from that project in my collection including a signed pic from Tom McMurtry. Great story here Mustard!

[adamh]

as an engineer that commonly gets into situations where the design requires an "ugly" or asymmetric feature, i absolutely love this whole oblique wing concept

[tristandawson]

As an aerospace engineer, I think the stability and control issues are easy to overcome with modern computers and algorithms. However, I would be significantly worried about the structural stability of the wing, particularly aeroelastic flutter. This was a particularly big problem on the X-29 and ultimately led to its cancelation. Additionally, it could be difficult (and heavy) to build a sufficiently strong rotating pivot to support the forces generated by the wing. Would be interesting to hear others thoughts on this issue

[Patrick-xtbm]

It's really wonderful to come across people who freely share valuable information online. You never know what kind of knowledge you might stumble upon that could have a lasting impact on your life.

[OhAwe]

No. Current manufacturers struggle with complexities such as doors.

[KF]

I’m sure this idea could find a great use for drones and cruise missiles, because they wouldn’t be so challenged in terms of structural design and often require folding/pivoting wings. And off course small and cheap unmanned crafts would allow to take much greater risks in terms of design.

[ccnutbeans]

11:12 that 737 thrust reverser is so cool

[SoGoYoko]

This was actually an Estes model rocket back in the 70's. Send it up as a rocket with the wings folded parallel with the rocket body with a B sized motor installed, at the end of the burn stage the reverse thrust that usually pushes out the parachute would instead trigger the wings to fold outward and the rocket would then glide back safely to the ground like a glider for another round. Este rockets were a very popular hobby for kids and adults back then. Thus, why I knew about this back when I was in fourth grade.

[shangerdanger]

obviously the main problem is that it doesn't look as cool/pointy, and being pointy is very important for jets and rockets and stuff

[theundiscoveredjourney_]

The wait for Mustard videos is long but still worth it.

[fvyffit]

I remember building an Estes model rocket based on this concept back in the early-mid 70's. It was called the Scissor Wing Transport. It launched with the wing stowed and when the recovery charge separated the booster, it released the wing which pivoted into position (via orthodontic rubber bands) and the fuselage came down as a glider. Coolest rocket I ever built.

[fridaycaliforniaa]

Fun fact : the two engines for the AD-1 were two little French _Microturbo_ TRS-18 engines that were derived from versions initially designed mostly for cruise missiles, surveilance and target drones (Sea Eagle, RBS-15, MQM-107 Streaker, and many others). For « manned » use, they received better bearings, a better lubrication system, more reliable parts and some other mods that allowed them to become more than a « single use engine » like they were before, as a means of propulsion for missiles (sorry I'm French, I hope my english isn't dog juice ^^).

[phoenix__rose]

Ya know, I love these videos, but damn is it always depressing learning what we could've had.

[smoketinytom]

It might have been 116 days since the last Mustard video, but it's worth it every time.

How many future engineers will credit his work that got them into the field...

[American_Jeeper]

You are rapidly becoming my favorite channel. Not only was this one hell of an informative video, you took your middle finger and rammed it straight up YouTube’s ass with Nebula…I love it!

[FreedomTalkMedia]

The bottleneck for most air travel is the airport. We typically spend a lot more time getting to, at, and getting from airports than we spend actually flying.

[ConnorPriola]

Typically, mustard talks positively about theoretical designs before demonstrating how they weren’t nearly as good as they seemed. This is the first one where it seems like there actually weren’t many downsides that couldn’t easily be solved with modern tech.

[thomasxl]

Me before the video: "This looks pretty silly"

Me now: "Sideways wings are the future of air travel, I'm gonna take over Boeing"

[Benblender]

Such high quality in this video, love the renders you've made.

[vanswift]

Has no one ever thought of trying to use two much smaller sized oblique wings that would work on a X configuration making up the same amount of lift without the problems mentioned on the video ?
I'm not an engineer, but it came into my mind as I was mulling the video and I was surprised it wasn't mentioned.