Its all in the wings
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From: nowhere
Its all in the wings
This is strictly a comment by someone else in an article that I recently read but I found it interesting from a historical aircraft design point of view....
"The B717-200 is actually a very good Aircraft, much better reliability than the MD80 and MD90's. It has a big disadvantage in its old wing design from the DC-9-33 made in Korea. Douglas stopped making competetive wings after the DC-8-62/-63, not having their own big wind tunnel like Boeing was a big part of it. A consulting von Karmann could only do so much vs. Boeings George Schairer working the Boeing wind tunnel. Airbus benefitted from the RAE and other European wind tunnels to design the Airbus wings. Hence without great wings an Aircraft design is crippled no matter how good the rest is."
"The B717-200 is actually a very good Aircraft, much better reliability than the MD80 and MD90's. It has a big disadvantage in its old wing design from the DC-9-33 made in Korea. Douglas stopped making competetive wings after the DC-8-62/-63, not having their own big wind tunnel like Boeing was a big part of it. A consulting von Karmann could only do so much vs. Boeings George Schairer working the Boeing wind tunnel. Airbus benefitted from the RAE and other European wind tunnels to design the Airbus wings. Hence without great wings an Aircraft design is crippled no matter how good the rest is."
Joined: Jan 2008
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From: Denver
I have all kinds of problems with the quoted paragraph:
"wing design from the DC-9-33 made in Korea." ???? Not sure whether this is supposed to mean: a wing designed in Korea, or a wing manufactured in Korea, or a DC-9-33 made in Korea, or all of the above, or none of the above - poorly structured sentence.
The B712 wing was the DC/MD design that served for 50 years - outsourced to a Korean factory (Halla) by Boeing for that particular version. Unless one has an outdated view of Korean manufacturing skills, it's no different than the previous made-in-USA wings. It was (always) a simpler wing, appropriate for a less-expensive shorter-route jet (simple two-position slats (or none in the DC-9-10) and simple drop-hinged flaps)
I don't see any evidence that the B717-200 is a "crippled" design. Delta laps them up and jest luvs 'em. Certainly not aerodynamically (it may have been crippled during production life due to market positioning and changes, post-9/11 aviation slump, more modern competitive airframes overall, etc. etc. - but not the wing)
Not sure how much advantage a "big" wind-tunnel offers over some other size (MD did have their own wind tunnels, and access to others (NASA/Ames among others).
https://rotorcraft.arc.nasa.gov/Publ...cklin_1994.pdf
As with any logical chain - first one has to prove the assumptions are true, accurate and applicable - only then we can discuss whether the conclusions are true.
In other words, the "history" given above seems questionable - but your title is often very true - many aircraft have most certainly depended on unique wing engineering for their existence.
"wing design from the DC-9-33 made in Korea." ???? Not sure whether this is supposed to mean: a wing designed in Korea, or a wing manufactured in Korea, or a DC-9-33 made in Korea, or all of the above, or none of the above - poorly structured sentence.
The B712 wing was the DC/MD design that served for 50 years - outsourced to a Korean factory (Halla) by Boeing for that particular version. Unless one has an outdated view of Korean manufacturing skills, it's no different than the previous made-in-USA wings. It was (always) a simpler wing, appropriate for a less-expensive shorter-route jet (simple two-position slats (or none in the DC-9-10) and simple drop-hinged flaps)
I don't see any evidence that the B717-200 is a "crippled" design. Delta laps them up and jest luvs 'em. Certainly not aerodynamically (it may have been crippled during production life due to market positioning and changes, post-9/11 aviation slump, more modern competitive airframes overall, etc. etc. - but not the wing)
Not sure how much advantage a "big" wind-tunnel offers over some other size (MD did have their own wind tunnels, and access to others (NASA/Ames among others).
https://rotorcraft.arc.nasa.gov/Publ...cklin_1994.pdf
As with any logical chain - first one has to prove the assumptions are true, accurate and applicable - only then we can discuss whether the conclusions are true.
In other words, the "history" given above seems questionable - but your title is often very true - many aircraft have most certainly depended on unique wing engineering for their existence.
Joined: Jul 2013
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From: Everett, WA
The B712 wing was the DC/MD design that served for 50 years - outsourced to a Korean factory (Halla) by Boeing for that particular version.
Unfortunately it was that same outsourcing mentality that the former MacDac execs brought to Boeing after the merger that crippled the 787 development...
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From: Seat 1A
What's wrong with a piece of railway line for your wings? Tough-as!! 
717 has a "dial a flap" system for takeoff: infinite angles between 0° and 20°; I assume, to extract the best out of/compensate for the "slab" of metal...
717 has a "dial a flap" system for takeoff: infinite angles between 0° and 20°; I assume, to extract the best out of/compensate for the "slab" of metal...
Last edited by Capn Bloggs; 25th November 2017 at 08:32. Reason: grammar
Joined: Feb 2013
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From: 60 north
Fokker 28/100
I have had the honor to listen to the ex Fokker people at Screiner now Cae about how excellent the wing design was and I suppose it was in its days.
They went on and on about restarting the production of a F100Neo. And they claim Airbus used some of it!
As a pax and occasional Jumpseater on the MDs I loved it.
( Minus the odd time I was sitting in aft A seat, my goodness what raket.)
The new 717 must have been excellent, but there is a point were You need a clean sheet new design. That point was economical and coincided with Boeing and 9/11 .
Speaking of wich I still think the 737-800 is to noisy for pax behind , say, row 12. The tail mounted engines still is better for Pax comfort and gives a cleaner wing design.
Just look at the Global, and tell me I am wrong.
The wingmounted engine airplanes are in my book the WW Beatle of the sky.
Simple and unsofisticated and cheap. The MoneyMens dream.
Lastely , I love my old 738 but some times when heavy and gusty we are are looking at bloody Spaceshuttle Flyspeeds on approach.
They went on and on about restarting the production of a F100Neo. And they claim Airbus used some of it!
As a pax and occasional Jumpseater on the MDs I loved it.
( Minus the odd time I was sitting in aft A seat, my goodness what raket.)
The new 717 must have been excellent, but there is a point were You need a clean sheet new design. That point was economical and coincided with Boeing and 9/11 .
Speaking of wich I still think the 737-800 is to noisy for pax behind , say, row 12. The tail mounted engines still is better for Pax comfort and gives a cleaner wing design.
Just look at the Global, and tell me I am wrong.
The wingmounted engine airplanes are in my book the WW Beatle of the sky.
Simple and unsofisticated and cheap. The MoneyMens dream.
Lastely , I love my old 738 but some times when heavy and gusty we are are looking at bloody Spaceshuttle Flyspeeds on approach.
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From: Nearer home than before!
You're not wrong- The NG was IMHO, a compromised design. They really should have moved the ailerons outboard and filled the space with more flap area.
Still no sign of it in the MAX after 20 years of poor crosswind control and limited short field performance as a result.
Still no sign of it in the MAX after 20 years of poor crosswind control and limited short field performance as a result.
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From: Everett, WA
The tail mounted engines still is better for Pax comfort and gives a cleaner wing design.
Just look at the Global, and tell me I am wrong.
Just look at the Global, and tell me I am wrong.
Wing mounted engines are near the nominal CG so you don't end up paying twice when the engine weight inevitably goes up.
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From: OZ
Blu-y, don't be so dismissive of wing mounted engines. They are a very good practical compromise for so many reasons. Look up and think about engine wing bending relief, ease of maintenance, fuel line protection, fire safety of pods, fuel feed by gravity, lack of fuel lines through the fuselage, various aerodynamic advantages, the list goes on. It is definitely not because it is a cheap solution, rather it is a very good design feature.
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We might see tail mounted engines come back soon on future airplane layouts with all the new unducted fan engines envisioned to power them and their "clean" wings getting really complicated with all the morphing stuff in them.
Joined: Feb 2013
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From: 60 north
Ballast now there is something You want to avoid in a new aircraft!
They gave us iPads and tossed out the navbag of 8kg, that is how allergic to carrying any extra weight the MoneyMen are. Now we have no paper charts WHATSOEVER, smart.!
Anyway , TD didnt some MacDc staff go to Embraer and continue the tailmounted engine saga?
So as I understand it , a tailmounted engine a/c is potentially a more efficient a/c but more challenging design wise. Ie more expensive.
And we all have seen the effect off lack of deice and all sorts of stuff being flung into the engines.
As I have already stated: The 737 born the same year as me is the ultimate Beetle and with the new wing on the 700 and 800 ( I think that is when the present one came) and the new engines, the basic 737 is going to carry on from 1967 to 2067!
Did the DC9 ever have that sort of potential? Me thinks not!
I find it absolutely fascinating that Aviation have become the Sick Old Man of technological development.
When Hitler was so proud of the WW Beetle that Herr Porche presented in 1935 , he sure as dirt did not expect it to end its days ,slightly modified in the 1990s from a Mexican factory!!
Thinking of that, I would not mind having WW Beetle , ca 1969.
At least I can fix the engine if needed, and fantastic on snow.
Aero dynamic and tailmounted engine.
Anyway, got to pull the net!
They gave us iPads and tossed out the navbag of 8kg, that is how allergic to carrying any extra weight the MoneyMen are. Now we have no paper charts WHATSOEVER, smart.!
Anyway , TD didnt some MacDc staff go to Embraer and continue the tailmounted engine saga?
So as I understand it , a tailmounted engine a/c is potentially a more efficient a/c but more challenging design wise. Ie more expensive.
And we all have seen the effect off lack of deice and all sorts of stuff being flung into the engines.
As I have already stated: The 737 born the same year as me is the ultimate Beetle and with the new wing on the 700 and 800 ( I think that is when the present one came) and the new engines, the basic 737 is going to carry on from 1967 to 2067!
Did the DC9 ever have that sort of potential? Me thinks not!
I find it absolutely fascinating that Aviation have become the Sick Old Man of technological development.
When Hitler was so proud of the WW Beetle that Herr Porche presented in 1935 , he sure as dirt did not expect it to end its days ,slightly modified in the 1990s from a Mexican factory!!
Thinking of that, I would not mind having WW Beetle , ca 1969.
At least I can fix the engine if needed, and fantastic on snow.
Aero dynamic and tailmounted engine.
Anyway, got to pull the net!
Joined: Nov 2000
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"I find it absolutely fascinating that Aviation have become the Sick Old Man of technological development."
I can't see that happening. Just look at CFRP use, aerodynamics, systems architecture, cockpit design, FBW and manufacturing. Way ahead of the car guys that still build the "new beetle" and chip tune their emissions.
I can't see that happening. Just look at CFRP use, aerodynamics, systems architecture, cockpit design, FBW and manufacturing. Way ahead of the car guys that still build the "new beetle" and chip tune their emissions.
Thread Starter
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From: nowhere
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From: Everett, WA
The location of the wing relative to the fuselage is one of the first things that have to be established when designing an aircraft, not something you can mess with less than a year prior to first flight when you find out the engine just got a lot heavier.
PDR, one ton per engine, there are two (at least). Also, there is already a lot of stuff at the pointy end that can't be readily moved - hence when you start talking thousands of pounds of ballast you can't put it in the most efficient location.