We know a lots of advantage of FSW, and most of them seems more adopt to commercial plane rather than military fighter.
Otherwise, we have an additional advantage of it.
We know the noise will transmit via solid more than liquid or gases, therefor, most noise from engine to cabin is via wing, this is why we saw some engines were put at rear of fuselage for elongating the distance from noise source to top class cabin.
If plane has FSW, then noise from engine nacelle will transmit to rear part more than closing first class cabin.
…… ellipsis for aerodynamic analysis.
By: Adrian_44 - 3rd November 2011 at 04:30
Re: Why no FSW on Comercial plane?
A commercial FSW isn’t a specifically good idea for a large airliner for some of the reasons stated above.
People often discuss the FSW its efficiency, etc. among some of the problems that plague the FSW is the problem with the wingtip. In a BSW the turbulence move away from the fuselage, where it can be controlled more easily. With the FSW, the air flow moves towards the fuselage. Back at the wingtip, the additional lift can cause problems not encountered with other wings. The outer wing in its flexing has a bad tendencies of when torque is applied to the outer wing, the leading edge lifts and the wing can rupture and tear off the outer ⅓ of the wing!
There are definite reasons the NASA & Germany explored the X-29 and Russia with Su-47. These two programs went no further than the testing stage! These planes provideded data but, that is it.
The 3-engined aircraft arose due to mis-matched aircraft size to available engine thrust.
United Air Line’s major hub of operations was in Denver, Co. They needed a jetliner that could take-off from Denver’s International air port. At temperatures at or above 95°, the runways are at an altitude of 5,280-ft. above sea level and, at the maximum take-off weight!
Engines at the time did not produce enough thrust for just two engines to be the solution. So the usage of three engines were used to meet these specs. Plus, the engines near the center-line of the airliner, tends to encounter less problems when one engine has to be shut down. I am not sure whether it was either UAL or Boeing that proposed a three engine airliner. Boeing’s met the specs and produced the B-727 mainly for a nitch market, smaller than the B-707 type airliners and larger than the B-737 that was in development.
By: Amiga500 - 2nd November 2011 at 12:06
An interesting aside: would there ever be a new three-engined design, or has modern engine technology made that format obsolete?
I’ll not say never, but I would say very, very, very unlikely.
The 3-engined aircraft arose due to mis-matched aircraft size to available engine thrust. The modular concept employed in engine design since the 80s has mostly rendered this problem irrelevant.
Additionally, there are intrinsic problems and compromises with 3-engined aircraft that make them undesirable for a whole load of reasons. They were essentially a band-aid fix to a problem that no longer exists.
By: Arabella-Cox - 2nd November 2011 at 08:20
The industry conservatism is a very important point. Airlines expect aircraft to look a certain way because that’s what their passengers expect. Thus, it would be a very brave manufacturer indeed who introduced something radical, so I reckon we’ll have the twin/four-underwing-engined format for a considerable time yet.
An interesting aside: would there ever be a new three-engined design, or has modern engine technology made that format obsolete?
By: Distiller - 1st November 2011 at 12:33
Because little Jimmy would say: ‘Look mommy! They mounted the wings the wrong way ’round!’
A commercial FSW isn’t a specifically good idea for a large airliner for some of the reasons stated above. Last time someone tried it on a smaller scale it wasn’t vastly successful either (HFB Hansa Jet).
And because the industry is conservative. Can’t even get BWB (Blended Wing Bodies) online. And that would actually be a good idea, economically.
By: Arabella-Cox - 1st November 2011 at 11:38
It would look silly, for one thing.
By: Arabella-Cox - 31st October 2011 at 21:46
Can you imagine an A380 with a forward swept wing?
By: Amiga500 - 31st October 2011 at 21:13
Quick comparison of a Learjet 23 to a Hansa.
The lear has smaller engines, a smaller wing area, has a much lighter OEW, but has a higher MTOW, can climb better, has a better range and can fly faster.
The Lear 23 became the template for bizjet design.
The Hansa… well…
By: chornedsnorkack - 31st October 2011 at 20:56
A civil jet with forward swept wing is HansaJet.
How does the weight, handling and maintenance of a HansaJet compare with other similar sized jets? Like Learjet?
By: Amiga500 - 31st October 2011 at 12:20
My “so-called” aeroelasticity definitely applies to subsonic flight.
Google is your friend.
By: emile - 31st October 2011 at 11:21
Yes there is.
Google “aeroelastic stability” and/or “aeroelastic divergence”.
Proof that you can deal with the afore mentioned aerelasticity issues throughout the life of the aircraft and in the event of impact damage to the leading edge.
Your so-called aerolasticity are well known, but it merely appears while entering transonic and supersonic flight, there is nothing to do with certain subsonic flight
By: Amiga500 - 31st October 2011 at 09:55
To the OP: This is not Airliners.net. We do not use acronyms for everything here.
Surely you mean:
To the Original Poster: This is not Airliners.net. We do not use acronyms for everything here.
:p:p:D:D
By: Amiga500 - 31st October 2011 at 09:54
There is no fundamental different structure between FSW and BSW.
No additional weight growth compare to Backward Swept Wing, if you understand their structure by sharpe.
No internal volume reduced by same reason above
Yes there is.
Google “aeroelastic stability” and/or “aeroelastic divergence”.
What’s certification?
Proof that you can deal with the afore mentioned aerelasticity issues throughout the life of the aircraft and in the event of impact damage to the leading edge.
By: Arabella-Cox - 30th October 2011 at 18:01
I had to google FSW because I have no idea what you are talking about.
Anyway way, clearly it would be inappropriate to have a ‘Female Sex Worker’ on a commercial aircraft:dev2:
Oh, I thought it was the Family Services of Westchester, which would also be of limited use in a plane :diablo:
By: J Boyle - 30th October 2011 at 15:52
… clearly it would be inappropriate to have a ‘Female Sex Worker’ on a commercial aircraft:dev2:
I don’t know, I could see certain airlines having them as another profit center….they could convert a galley since they aren’t used any longer.
A great idea, right up there with pay toilets.:diablo:
By: J Boyle - 30th October 2011 at 15:50
… clearly it would be inappropriate to have a ‘Female Sex Worker’ on a commercial aircraft:dev2:
I don’t know, I could see certain airlines having them as another profit center….they could convert a galley since they aren’t used any longer.
A great idea, right up there with pay toilets.
By: Bmused55 - 30th October 2011 at 15:36
For Your Information
By: spitfireman - 30th October 2011 at 11:43
Just FYI for anyone asking.
Eh?
By: Bmused55 - 30th October 2011 at 10:26
FSW = Forward Swept Wing
Just FYI for anyone asking.
To the OP: This is not Airliners.net. We do not use acronyms for everything here.
Perhaps it would have been much better for you to atleast type “Forward Swept Wing” once, so that others would know what “FSW” meant.
By: emile - 30th October 2011 at 05:27
Umm.. well if you thought it about logically youd know why.
1) Most airliners have engines under the wings, a FSW will need to be stronger in all cases to hold the weight of engines.
There is no fundamental different structure between FSW and BSW.
2) A FSW airliner wont be able to park at ANY AIRPORT IN THE WORLD which uses an aero bridge…
I can’t see support to your oppinion
– questionable aerodynamic benefit over a well designed wing
– weight growth
– reduced wing internal volume for fuel
– certification
– uncertainties over structural life-span
No additional weight growth compare to Backward Swept Wing, if you understand their structure by sharpe.
No internal volume reduced by same reason above
What’s certification?
uncertainties? yes, but we need no supersonic flight up to now….
By: slipperysam - 30th October 2011 at 01:01
Umm.. well if you thought it about logically youd know why.
1) Most airliners have engines under the wings, a FSW will need to be stronger in all cases to hold the weight of engines.
2) A FSW airliner wont be able to park at ANY AIRPORT IN THE WORLD which uses an aero bridge…
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October 29, 2011 at 8:18 am