Why Are Airplane Wings Angled Backwards??

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[airplane]

Lets give credit accordingly. The Germans invented the first Jet fighter called Messerschmitt Me 262 in 1942. They were the ones who discovered the wing design that allowed airplanes to fly faster. I don't have any admiration for Nazi German but many inventions were appropriated by allies engineers that later took credit by things that the Germans developed. It is sad but war is the motivation for technological advance still today.

[thethievingmonkey]

The sweep angle in wings of modern sub-sonic planes has little to nothing to do with supersonic flow. It's the there to avoid aeroelastic divergence. In summary, lift will cause bending and torsion on the wing. As the torsion increases the angle of attack, it increases lift, and that can cause a feedback loop where the wing deforms increasing lift, thus increasing deformation and so on until breaking. Back-swept wings result in negative coupling between bending and torsion on the wing, and so the bending of the wing counteracts the increasing torsion, keeping the angle of attack at safe values. The opposite happens with forward-swept angles, so you would need much stiffer wings to avoid divergence.

[StRM]

What about Forward-swept wings? can you make a video?

[SephirothRyu]

This really is an incredible video for engineering students in the field of aeronautics. Its so quick and succinct while bringing forth some critical concepts in an easy to understand method.

[aouneseghirsofiane]

1:20, i think the lift is reduced on the tail wing (elevator) due to a downwash decrease caused by the center of pressure and shockwaves moving backward (Mack Tuck)

[armandcarloq.agbulos]

Your videos are highly educational and can deliver information in a very detailed way. Thanks!

[zippersocks]

I saw this about three years ago when this vid was posted. I randomly watched it again and I’m so happy to have seen it.

[welshpete]

The Gemans' were the first to use swept back wing. When a Scientist noticed the angle that the water came off the stern of a ferry . He used everyday to go to school when he was a child . He used this angle to help to solve the problem of highspeed flight . Messerschmitt Me 163 being one of the first to it.

[Bartonovich]

This isn't how swept wings work. Spanwise flow is undesirable in any wing--of which straight wings certainly are subject to. Look at all of the aircraft--both straight wing & swept wing--that use wing fences, vortilons, dog toothed leading edges, and other devices to PREVENT spanwise flow.
What a swept wing does is allow you to make a thinner effective airfoil (because the airflow is going over the wing in the direction of the undisturbed air--rather than perpendicular to the wing) without the structural challenges of making a thin airfoil.

[olivialambert]

You seem to have done a lot to ignore non-American advances in high speed flight. For example a little mention that "it was based on a German prototype" ignores the huge, massive advances Germany made during WW2 to culminate in swept wing planes in production and in combat during the war. The Bell X1 I could forgive you for, as people seem to constantly recite the American suggestion that it was America breaking the pattern.

The reality is that the vast majority of the science and technology behind breaking the speed of sound came from Britain who were conducting similar tests. The British gave that data to the Americans on the promise that America would fund the tests (everyone else who participated in WW2 was incredibly poor at the time) and that America would use the mass of British technology in those tests, break the sound barrier, and give Britain the technology discovered by the X-1 tests.

Well the X-1 broke the sound barrier and America said "thanks, bye" essentially. The irony being Britain was so close to breaking the sound barrier at the time, and the biggest and most important keys America lacked in breaking the sound barrier were discovered by Britain a long time ago, comparatively speaking. So yes America broke the sound barrier, but Britain discovered how it was done, invented the use of the all-moving tail surface with regards to Mach 1 speeds, and generally gave America an absolute shit load of help in breaking that magic number.

So sure, America has done a lot to advance flight technology after the 50s, but please don't ignore the advances made by everyone else. This was a triumph of all of mankind's ingenuity, not of America alone.

And truth be told, America was stuck in a rut regarding all of its military technology in the 50s. Air, land, and though admittedly they were doing great as far as naval was going that too was beginning to stagnate mid 50's. Its up for debate why, possibly because the people in power were all too old and resistant to change, I personally believe its because the rest of the world was at war and improvement was a necessity. This is all too evident when Russia is concerned who completely revolutionised the ground war in response to German attacks, and quite frankly a large part of what they learnt is still in use today, at least in the broad strokes.

[bergsteirer]

I like this channel and watched your videos with great interest.
Unfortunatly this design wasn't developed by Americans but by Germans who reached +1000 km/h in 1944 with the Me 163.
The engineer of this plane was Alexander Lippisch who was brought to the States and helped the USAF to develope its inmature technical unnderstanding of avionics close to the sound barriere.
The german engineers where aware of these effects since at least 1934, this is why the Ju 87 already had a dive break to reduce speed and avoid the effect of shockwaves.

[AktienMitKopf]

Hi! Great Channel can I ask what software you use for the animation of your videos?

[makismakiavelis]

The Су-47 Беркут says: "fuck that i'm gonna have forward swept wings."
Also your videos are great. Are you going to be focused mainly on aerospace engineering in your videos? Because i like that.

[SDNorm]

I would have liked to see you also go into forward swept wings.

[uavpilot]

This video has answered my question. Thank you Real Engineering.

[Orc-icide]

Wow. This is an actual contribution to Youtube. Really great video.

[MFF]

You skipped by the first swept wing Jet the ME 262...

[EoinDineen]

I fucking love your videos. I need more.

[indoorherbivore]

Nice informative video. Although not related to swept wings, one key invention that made the Bell X-1 controllable was the all moving stabilizer. These are now standard on every aircraft that flies near or above Mach speeds.

[williamwallace]

FANTASTIC description of span wise flow!