Timeline for Can a 747 airfoil be scaled down for smaller jet planes?
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
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| Jan 3, 2023 at 18:37 | vote | accept | Justintimeforfun | ||
| Jan 3, 2023 at 3:15 | comment | added | CatchAsCatchCan | There is a general, and fundamental reason why this won't work as you expect. You can scale the aerofoil, but you can't scale the air. (At this point I recall that all the aerodynamics I learnt was 40+ years ago). To get similar behaviour at different scales you need to fiddle with the Reynolds number. This is why wind tunnel testing is sometimes done at low (perhaps cryogenic) temperatures, amongst other things. | |
| Jan 2, 2023 at 22:56 | comment | added | Max R | My thought is that in engineering, things are intertwined in a way that leads us to oversimplify cause and effect. Does the 747 perform the way it does because of the wing? Or was that wing design required by the performance characteristics of the plane? Advances in power plants tends to be the driving/limiting factor in airliner design, which in turn enables flight regimes that require a rethinking about wings. The question is “can I make a BD5 perform in a way that will benefit from that wing?” and not “will that wing improve the performance of the BD5”. | |
| Jan 2, 2023 at 22:19 | comment | added | quiet flyer | Re "As time progressed the profile of the wing evolved for more stability and acrobatic performance instead of stability and range." -- this is confusing. Maybe delete one of the "stability"s? | |
| Jan 1, 2023 at 22:55 | answer | added | Robert DiGiovanni | timeline score: 1 | |
| S Jan 1, 2023 at 22:34 | history | suggested | manassehkatz-Moving 2 Codidact | CC BY-SA 4.0 |
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| Jan 1, 2023 at 20:53 | review | Suggested edits | |||
| S Jan 1, 2023 at 22:34 | |||||
| Jan 1, 2023 at 20:28 | comment | added | sophit | Jetliner's airfoils are optimised to travel at some 900 kmh at 10'000 m altitude, I don't think that that airplane can reach such speeds and altitudes. Sweeping the wing back alters CG and aerodynamic center position i.e. longitudinal stability; plus wing becomes structurally heavier and more difficult to build; plus it brings some positive effect only at high subsonic speed. To get a better answer it should be made clearer the mission of the airplane: flying fast, far, agile, high, ... ? | |
| Jan 1, 2023 at 19:53 | comment | added | Frog | I’m not an authority on aerofoils but a reliable way to increase the efficiency and therefore the range would be to use a larger aspect ratio wing. The aerofoil will typically be chosen to be optimal for the altitude, loading, speed etc rather than the other way round. As far as scaling goes, yes this does work reasonably well of the scaling factor isn’t too big; even model aircraft can use sections that are similar to big jets. | |
| Jan 1, 2023 at 19:02 | history | asked | Justintimeforfun | CC BY-SA 4.0 |