gia777
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Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:15 am

I was wondering, why Airbus and Boeing never make an airplane like C5 super galaxy for commercial air travel purpose?
Cheers,

GIA777 :coffee:
 
SuperAzusa
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:18 am

I believe it is aerodynamically inefficient. The only reason why military transports have them on top is to reduce the risk of the engines sucking in foreign objects.. and short take off as military planes may operate on poor runways or even dirt/grass.

civilian airliners usually have the luxury of cleaner and longer runways.
 
bennett123
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:26 am

How about the BAE 146
 
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LAX772LR
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:30 am

gia777 wrote:
I was wondering, why Airbus and Boeing never make an airplane like C5 super galaxy for commercial air travel purpose?

Switch your question around:
Why WOULD they?

What would they stand to gain by doing so?
I myself, suspect a more prosaic motive... ~Thranduil
 
Noshow
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:53 am

There is a spar running through the wing from one wingtip to the other. It might limit or divide the main cabin if you build a passenger aircraft with a high wing. If you want easy low deck access, like on a military transport, it's the other way around and a high wing provides some unobstructed main deck.
Last edited by Noshow on Thu Oct 11, 2018 6:53 am, edited 1 time in total.
 
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KLMatSJC
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:53 am

SuperAzusa wrote:
I believe it is aerodynamically inefficient. The only reason why military transports have them on top is to reduce the risk of the engines sucking in foreign objects.. and short take off as military planes may operate on poor runways or even dirt/grass.

civilian airliners usually have the luxury of cleaner and longer runways.


That and ease of loading in cargo through the nose as well. It's easier to lower a nose to the ground if you don't have to worry about an engine hitting the ground.
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TheFlyingDisk
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:59 am

bennett123 wrote:
How about the BAE 146


Or the Dornier 328 Jet. Or the An-72/74
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sibibom
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 7:01 am

Image

well do ATRs and Bombardiers count?
 
sholmes
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 7:55 am

sibibom wrote:
Image
well do ATRs and Bombardiers count?

I would say no: the question is on "commercial jets".
A few commercial jets have however been built with wings on the top, as also recalled in some posts above.
 
OlafW
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 8:19 am

When you compare the Dash 8 and the ATR to the Galaxy and BAe 146, you will see that the latter have the wing going through the fuselage whereas the smaller ones have it going above the fuselage (or have the fuselage suspended from the wing, whichever way you look at it). I guess that makes a difference, at least for the passenger experience, as I remember that in the Avros the overhade compartments below the wings were tiny compared to those front or aft of the wing.
I have also wondered about this question, using the following thought: Many things in aircraft design are inspired by what you find in nature, namely birds. Winglets are one thing that comes to mind, retractable gear also. So why don't aircraft reflect the "construction" of a bird more? I don't think there's any bird out there in a "low-wing configuration". Seeing that birds have very pronounced breast muscles, do high-wing aircraft need more stabilisation on the underside of the front fuselage, and it's not needed or easier to construct on low-wing planes?
 
CanadianNorth
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 8:42 am

As with almost anything, designing aircraft is always a compromise.

Low wings:
- If you have a round-ish fuselage the wing box can go through the fuselage and still have an uninterrupted main deck cabin. BAe146 has reduced cabin space at the wing, ATRs and Dash 8s have the wings mounted above the fuselage which can create more drag.
- Wing mounted engines are easier access for maintenance purposes.
- You don't need to have abnormally long landing gear a la Dash 8 which adds a lot of weight or an extra fuselage "pod" to house the gear a la ATR which adds drag and tends to be less stable in a crosswind.
- More ground clearance on the fuselage
- Low wings are easier to inspect and de-ice

High wings:
- More ground clearance for the engines
- Easier loading/unloading as the door height tends to be closer to the ground.
- More stability (dihedral on the wings is an easy way to add stability, many high wing designs actually use anhedral as they are if anything too stable otherwise).

When designing an airplane you pretty much have to just go through the advantages and disadvantages of each and decide which points are worth the most for the intended role of your airplane.
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vhtje
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 8:43 am

Whatchu talkin' 'bout, Willis?

Image

Image

Note: apologies, and full credit to, the photographer. I had to do something clever to display the photos, as linking from the Photos database appears to be broken.
I only turn left when boarding aircraft. Well, mostly. All right, sometimes. OH OKAY - rarely.
 
Jomar777
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:04 am

I think the topic should be renamed to "Why no Long Haul Commercial Jets have their wings on the top?"
Boeing and Airbus have their designs based on fleet commonality so, given their LH aircrafts have what we could call "low wing", their SHs would be the same (even though, theoretically, it is possible to have a high wing SH Jet like, for example, the BAE146 or, more recently the An146).

Having cleared this, there are several reasons why passenger aircrafts are low winged - less drag, silent cabins, avoiding restrictions on the cabin in regards to seat offering etc. etc.
 
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Clipper101
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:28 am

It is due to Stability & Control issues that characterize high wing profiles in contrast to low wings:

High wings are more stable at low speeds, less stables at high speeds contrary to low wings which are less stable at low speeds & more stable at high speeds.

Thus, high stability of high wings is seen beneficial to serve the purpose of Take off/landing from short runways (airstrips) with their high wing profile making them adequate to install engines with much ground clearance to make for operation from unpaved runways for example.

Talking high wing & short runways, mostly high wings are associated with propeller technology, propellers have the characteristic of generating higher initial acceleration at take offs more than jets do, so you would have the combination of high wings & propellers as a good combination for take offs from short runways especially unpaved.
 
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Matt6461
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 1:27 pm

The main reason we don't see large high-wing airliners is water evacuation. ATR has hatches in the ceiling to facilitate water exit; difficult to imagine a practical solution for a B777.

For bigger planes the room is definitely there for high-wing config without impinging on cabin and/or causing more drag. The arrangement would be better on these issues for a widebody, actually, because it would free up a lot of cargo space and use wasted crown space.

Additional drawbacks of high wing:
-Requires T-tail, which is structurally inefficient.
-Requires attaching landing to fuselage, which is less efficient than MLG-wingbox connection.

Besides the advantages I listed above (space utilization and drag profile), high-wing can:
-remove the constraint on engine diameter, which will be a big factor going forward.
-enable shorter MLG, which ameliorates the MLG-fuselage problem
-enable strut-braced wing technology, which IMO is the future

Image

I'll be interested to see how they solve the water evacuation issues. I'd imagine that a large plane with a big belly may have sufficient buoyancy for evacuation even with a high wing. Maybe a solution is feasible wherein flotation devices combine with evacuation slides to ensure sufficient buoyancy.
 
ChrisKen
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 1:54 pm

Matt6461 wrote:
ATR has hatches in the ceiling to facilitate water exit;.


You mean it has a single cockpit escape hatch for the crew, as does just about every other commercial airliner in production (hatch/window). It's not intended for passenger escape, water or otherwise. Those four exits can be found in their usual place at the front and rear of the pax cabin.
 
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 1:56 pm

One other nuance, beyond the significant items already mentioned, is operational accessibility. Deicing, mx access to the wings on a turn or routine mx cycles, etc. There is practicality in having low wings on commercial aircraft.
 
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NameOmitted
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 2:41 pm

From a structural standpoint, is it easier to build a low wing aircraft, which is 2 cantilevers on a foundation than a high wing, which if two cantilevers suspended from a point?
 
friendlyskies22
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 2:44 pm

Matt6461 said it in post #16 -- water landing. Look at the pix of US Airways 1549 in the Hudson. The air in the low wing gave the occupants precious minutes to
evacuate, and something to stand on. A high wing could have been a different story.
 
citationjet
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:12 pm

bennett123 wrote:
How about the BAE 146


TheFlyingDisk wrote:
Or the Dornier 328 Jet. Or the An-72/74


vhtje wrote:
Whatchu talkin' 'bout, Willis?


The thread title didn't specify manufacturer, but the OP's question was: why Airbus and Boeing never make an airplane with the wing on top?
Sure, there are examples of high wing commercial jets, but none of these were built by Airbus or Boeing.
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Bobloblaw
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:27 pm

Does a high wing aircraft generate more lift and can carry more payload?
 
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aerolimani
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:51 pm

friendlyskies22 wrote:
Matt6461 said it in post #16 -- water landing. Look at the pix of US Airways 1549 in the Hudson. The air in the low wing gave the occupants precious minutes to
evacuate, and something to stand on. A high wing could have been a different story.

There's some discussion here about how it works on the DHC8/Q400. I'm not sure how the ATR deals with a water landing evacuation.

Ditching With A DASH8-Q400: viewtopic.php?t=774517
 
32andBelow
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 6:51 pm

sholmes wrote:
sibibom wrote:
Image
well do ATRs and Bombardiers count?

I would say no: the question is on "commercial jets".
A few commercial jets have however been built with wings on the top, as also recalled in some posts above.

Atrs and Qd have jet engines
 
citationjet
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 7:10 pm

sibibom wrote:
well do ATRs and Bombardiers count?

sholmes wrote:
I would say no: the question is on "commercial jets".


More specifically, the OP's question was why doesn't Airbus and Boeing not build commercial jets with the wings on top. Last I knew, ATRs and Bombardiers were not built by Airbus or Boeing.
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WayexTDI
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 7:23 pm

32andBelow wrote:
Atrs and Qd have jet engines

Generally, turboprops are not considered jet engines.
 
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PatrickZ80
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 8:19 pm

Boeing did make some high-wing jets like the C-17 Globemaster and the C-5 Galaxy, however those are military aircraft. They're not designed for civilian use.

Those aircraft also got a higher fuel burn than civilian aircraft of the same size, that's why civilian airlines aren't interested in them. For an airline fuel burn matters, however for the military other things are more important such as the ability to land on bad runways. Then if the aircraft has a higher fuel burn, so be it.

The reason turboprops are high-wing aircraft has to do with the propeller blades. They take up quite some space and you don't want them to hit the ground, so they have to be quite high up. Since the plane itself is rather low they solve this by mounting the wing to the top of the airplane. At least, most turboprops do. For a bad example look up the Saab 340, which is a low-wing turboprop. Those blades almost touch the ground and I believe this actually happened quite a few times.
 
N766UA
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 8:29 pm

WayexTDI wrote:
32andBelow wrote:
Atrs and Qd have jet engines

Generally, turboprops are not considered jet engines.


Of course they are. They’re just not turbojets...
 
nikeherc
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 8:46 pm

With high wings, the wing box can intrude into the passenger compartment. On the Fairchild F-27, I seem to recall a dip in the aisle to maintain headroom. You can also have very long gear struts. On a low wing airplane, the wing box merely divides the cargo hold. Also, the issue of fuel in the wings being above the height of the emergency exits would seem problematic.
DC6 to 777 and most things in between
 
32andBelow
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:08 pm

nikeherc wrote:
With high wings, the wing box can intrude into the passenger compartment. On the Fairchild F-27, I seem to recall a dip in the aisle to maintain headroom. You can also have very long gear struts. On a low wing airplane, the wing box merely divides the cargo hold. Also, the issue of fuel in the wings being above the height of the emergency exits would seem problematic.

The fuel isn’t a problem in c208, q400, atr why is it different if you don’t have a prop attached to the jet?
 
rutankrd
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:15 pm

Suppose we ignore the following

BAE 146 SERIES
BAE RJX SERIES
DORNIER 328JET
ANTONOV 148
ANTONOV 158
ANTONOV 72
ANTONOV 74
BAADE 152 abject failure admittedly

None of the above are/were high wing then ?
 
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September11
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:23 pm

Jet bridges could be a problem...
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hawaiian717
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:31 pm

PatrickZ80 wrote:
Boeing did make some high-wing jets like the C-17 Globemaster and the C-5 Galaxy, however those are military aircraft. They're not designed for civilian use.


C-17 is really a McDonnell Douglas product that Boeing inherited via merger. C-5 is a Lockheed product, not Boeing.

PatrickZ80 wrote:
For a bad example look up the Saab 340, which is a low-wing turboprop. Those blades almost touch the ground and I believe this actually happened quite a few times.


Other low wing turboprops include the EMB-110, EMB-120, Jetstream 31, 41, and ATP/Jetstream 61.
 
GalaxyFlyer
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:32 pm

C-17 was designed by McDonnell Douglas, the C-5 designed and built by Lockheed. Boeing got to the C-17 by acquisition of existing product.

GF
 
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hawaiian717
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:34 pm

September11 wrote:
Jet bridges could be a problem...


I flew on a Brussels Airlines Avro RJ100 last year and we boarded via jetbridge at Brussels.
 
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N14AZ
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:36 pm

PatrickZ80 wrote:
Boeing did make some high-wing jets like the C-17 Globemaster and the C-5 Galaxy.

You might want to review this statement...

Edit: Galaxyflyer was faster than me.
 
ZKNCI
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:41 pm

High wings either need long (heavy) landing gear from the wing, or extra fuselage structure to bear the loads from the wing box down to the fuselage mounted gear (also heavy). For the former, if it's a jet, that's a lot of space taken up by undercarriage which otherwise would be fuel or it needs an external pod, which adds drag (The Dash 8 can hide the undercart behind the engine being a turboprop, so less drag). For the latter, that's added drag and restricted undercarriage width, but the undercarriage does not need to be so large. On top of that, the wing either needs to be on top of the fuselage with a large fairing (like the ATR-72 or Do-328), or pass through the fuselage, which would limit headroom. On the C-5, not a problem as the deck which matters is the cargo below. On a commercial airliner, passengers wouldn't be pleased, while cargo doesn't care if it's in one or two bays with a wing between. Additionally, passengers probably wouldn't like seeing only the engine the whole flight! On the positive side, the lifting surface is uninterrupted, and the wing is less likely to catch FOD. And as the fuselage is generally a larger diameter than the engines, the engines are also higher than their clearance requirements, and so less likely to be damaged.

For loading, a high wing is great if you have little to no supporting gear, hence need built-in ramps and stairs. For most commercial jets this isn't necessary and such features would add weight, so any ground clearance needed to hang engines under a low fuselage is less critical. Also allows for later stretching. Turboprops more often see less-developed airports, and so the low floor helps with loading passengers and cargo where facilities are not available and limits the risk of damage from debris. From a maintenance point of view, the lower the access points and engines are, the better, and a low wing brings everything closer to being able to be serviced from the ground.

Long story short: a lot of trade-offs! :D

Matt6461 wrote:
Additional drawbacks of high wing:
-Requires T-tail, which is structurally inefficient.

Not necessarily. It is more common to have a T as it keeps the tailplane in clean air for a high-wing, but the Antonov turboprops (24/26/32/132), C-130, C-133, G-222, C-27J, CN235, C-295 all have high-wings, low tailplanes.

PatrickZ80 wrote:
The reason turboprops are high-wing aircraft has to do with the propeller blades. They take up quite some space and you don't want them to hit the ground, so they have to be quite high up. Since the plane itself is rather low they solve this by mounting the wing to the top of the airplane. At least, most turboprops do. For a bad example look up the Saab 340, which is a low-wing turboprop. Those blades almost touch the ground and I believe this actually happened quite a few times.

A high wing does add clearance, which reduces the risk of damage, but the clearance on low-wing props is comparable to low wing jets and prop-strikes are rare. Using the Saab 340 example, its clearance is 0.51m, compared with 0.48 to 0.64m on a 737-800. The 1900Ds landing on rougher strips, however, certainly got more chips than the Dash 8s due to the lower props, but that was due to debris thrown up rather than striking the ground. Low-wing turboprops aren't particularly uncommon, with not only the Saab 340 and its derivative Saab 2000, but also the Fairchild Metro, Embraer 110 and 120, Jetstream 31/32 and 41, BAe ATP and 748, Illyushin Il-114, Beech 1900, and smaller gen-avs such as the King Air and PC-12. They are quite fast, as the wing can be tucked up below the fuselage floor reducing drag as per the larger jets or with a small bump in the floor, but do need longer landing gear and are not as easy to turn-around on less-supported fields as their low-floor counterparts.
 
Tailwinds
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 9:59 pm

One thing I haven't seen mentioned here is the deck height. You typically want your deck placed such that the widest place is about shoulder level on a seated passenger: maybe about a meter below the widest point. So right away you can see that as the diameter gets bigger, so too does the area below the deck. On a widebody plane you get a LOT of volume down there. That volume needs to do something useful for the plane to earn its keep. It can hold the gear without needing some external pod. It can hold a fuel tank. It can hold a wing spar. In most planes it holds two wing spars and uses those as the structure framework to hold a fuel tank and the undercarriage, killing three birds with one stone.

One thing most of the passenger high-wings have in common is that they don't have a large volume below the deck to waste. Either the volume is so low that they have to put the luggage in a compartment at main-deck level, or the volume is just right to fill with luggage entirely and not have a lot of unneeded space.
 
citationjet
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 10:22 pm

rutankrd wrote:
Suppose we ignore the following

BAE 146 SERIES
BAE RJX SERIES
DORNIER 328JET
ANTONOV 148
ANTONOV 158
ANTONOV 72
ANTONOV 74
BAADE 152 abject failure admittedly

None of the above are/were high wing then ?


Read the OP. He is asking why Airbus and Boeing don’t build high wing commercial jets. None of your examples are Airbus or Boeing products.
Last edited by citationjet on Thu Oct 11, 2018 10:24 pm, edited 1 time in total.
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XRadar98
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 10:23 pm

PatrickZ80 wrote:
Boeing did make some high-wing jets like the C-17 Globemaster and the C-5 Galaxy, however those are military aircraft. They're not designed for civilian use


McD made the C-17, and Lockheed made the C-5 (and C-141)
 
Biscayne738
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Re: Why no commercial jets airlines build with wing on the top?

Thu Oct 11, 2018 10:43 pm

Sorry no Boeing or Airbus here, but a short list of a few regional high wing airliners:

Ford Tri-Motor
Shorts 330 & 360
Nord 262
DeHavilland Dash 7
De Havilland Twin Otter
Fokker F-27 & F-50
Fairchild FH-227
Dornier 228
Let 410

I'm sure I've missed a few...
 
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aeromoe
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 12:30 am

Matt6461 wrote:
Additional drawbacks of high wing:
-Requires T-tail, which is structurally inefficient.


Umm...no it doesn't. Ever seen the AN-124 and AN-225?
AA AC AS BA BD BF BN BR BY B6 CO CZ DG DL EA EI EN FL FT F9 HA HP ICX JI J7 KE KS LH MC NW OC OO OZ(1) OZ(2) PA PI PT QQ RM RO RV(1) RV(2) RW SK SM SQ S4 TI TS TW UA UK US UZ VS VX WA WN WS W7 XV YV YX(2) ZZ 9K
 
AtomicGarden
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 12:32 am

So we can all agree that high wing commercial jets exist but none is large or particularly succesful.
 
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afterburner
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 2:02 am

N766UA wrote:
WayexTDI wrote:
32andBelow wrote:
Atrs and Qd have jet engines

Generally, turboprops are not considered jet engines.


Of course they are. They’re just not turbojets...

Turboprop and turboshaft are gas turbine engines, just like turbojet and turbofan. However, the majority of people don't know (or don't care) about what type of engine inside an engine cowling. When there is a propeller attached to it, it isn't a jet engine to them.
 
32andBelow
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 2:06 am

afterburner wrote:
N766UA wrote:
WayexTDI wrote:
Generally, turboprops are not considered jet engines.


Of course they are. They’re just not turbojets...

Turboprop and turboshaft are gas turbine engines, just like turbojet and turbofan. However, the majority of people don't know (or don't care) about what type of engine inside an engine cowling. When there is a propeller attached to it, it isn't a jet engine to them.

Ok well this is an aviation website not USA Today. People here should know they turboprops are jets engines.
 
WayexTDI
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 2:47 am

32andBelow wrote:
afterburner wrote:
N766UA wrote:

Of course they are. They’re just not turbojets...

Turboprop and turboshaft are gas turbine engines, just like turbojet and turbofan. However, the majority of people don't know (or don't care) about what type of engine inside an engine cowling. When there is a propeller attached to it, it isn't a jet engine to them.

Ok well this is an aviation website not USA Today. People here should know they turboprops are jets engines.

Since most turboprop primary thrust is coming from the propeller, then do you consider piston engines equipped with a propeller a "jet engine"??? In both case, their thrust come from the prop.

I guess everyone has their own definition. Mine does not put the turboprop in the jet engine category.
 
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afterburner
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 2:55 am

32andBelow wrote:
Ok well this is an aviation website not USA Today. People here should know they turboprops are jets engines.

This is indeed an aviation website. However not all the members here are aviation experts. Some members join here to know more and learn about aviation.
 
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Matt6461
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 2:59 am

aeromoe wrote:
Matt6461 wrote:
Additional drawbacks of high wing:
-Requires T-tail, which is structurally inefficient.


Umm...no it doesn't. Ever seen the AN-124 and AN-225?


I stand corrected. Thank you.

A more accurate statement would be there must some mechanism - either elevation of the Hstab or enlargement - that accounts for greater wing-Hstab interference with a high wing.

The most common mechanism is the T-tail.

An-124/225 appears to place the Hstab higher than, or at least level with, the wing by curving the rear fuselage upwards and reducing taper on the north end of the fuselage y axis. That's not a free adjustment. It's still paying an Hstab price for the high wing, just not in the currency of T-tail.
 
PDX88
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 3:01 am

N766UA wrote:
WayexTDI wrote:
32andBelow wrote:
Atrs and Qd have jet engines

Generally, turboprops are not considered jet engines.


Of course they are. They’re just not turbojets...


Neither are modern commercial airliners. They're turbofans.
 
citationjet
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 3:21 am

AtomicGarden wrote:
So we can all agree that high wing commercial jets exist but none is large or particularly succesful.


Yes, and also that no high wing commercial jets are made by Airbus and Boeing, which was the question originally asked by the OP.
Boeing Flown: 701,702,703;717;720;721,722;731,732,733,734,735,737,738,739;741,742,743,744,747SP;752,753;762,763;772,773.
 
sibibom
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Re: Why no commercial jets airlines build with wing on the top?

Fri Oct 12, 2018 4:24 am

citationjet wrote:
sibibom wrote:
well do ATRs and Bombardiers count?

sholmes wrote:
I would say no: the question is on "commercial jets".


More specifically, the OP's question was why doesn't Airbus and Boeing not build commercial jets with the wings on top. Last I knew, ATRs and Bombardiers were not built by Airbus or Boeing.


Technically ATR is part-owned by Airbus.

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