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What are the advantages and disadvantages of a high-wing vs. low-wing aircraft design? When might one prefer one to the other?

Is the answer the same for large and small aircraft?

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This is actually a really hard question to answer, as there are a ton of factors. I'll try to cover a few.

  • Visibility is probably the reason you most hear when it comes to GA pilots.
    • High-wing aircraft offer better visibility below the aircraft, especially for passengers in 4-seat or larger aircraft, as the wing doesn't block it.
    • Low-wing aircraft can offer better visibility above the aircraft, as the wing remains mostly out of the field of view.
    • Note that a lot of midair collisions involve mixed types; low-wing aircraft descend into high-wing, or high-wing aircraft climb into low-wing.
  • Landing characteristics are different, as low-wing aircraft can incur more ground effect than high-wing.
  • Aerodynamic stability of the two designs differs a bit; the center of lift can be higher in a high-wing design, often offset with dihedral in low-wing aircraft.
  • Ground clearance (and debris protection), specifically in multi-engine aircraft, is going to be greater when engines are mounted on a high wing rather than a low wing. This is true of both propeller and jet engines, although propellers tend to have a larger radius for a given aircraft size.

There are a bunch more, but that ought to get the argument discussion going.

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    $\begingroup$ On the topic of visibility: when turning, high wings tend to block your view in the direction you are turning. $\endgroup$
    – sdenham
    Jun 12, 2014 at 16:31
  • $\begingroup$ a lot of noise is made around flights schools regarding high-wing versus low-wing accidents but I've never seen any evidence. $\endgroup$
    – rbp
    Nov 24, 2014 at 22:05
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    $\begingroup$ @rbp Yeah, there are plenty of high+low combo accidents out on record. That's the only configuration-related accident info I've seen. $\endgroup$
    – egid
    Mar 13, 2015 at 19:01
  • $\begingroup$ Are there advantages of high-wing in terms of aerodynamic efficiency (lift over drag)? $\endgroup$
    – Jonny
    Apr 27, 2015 at 7:16
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@Egid, your already gave really good and correct answer dealing with the most important benefits and downsides, or simple the most significant differences. I like to follow your invitation and add the differences I thought of and you have not already mentioned:

The additional ground clearance also benefits the maximum crosswind some high-wing aircraft can cope with, what in my eyes is also an important point.

Also high wing aircraft - talking about light sports - benefit the design of the fuel system as it allows consumption from both tanks simultaneously without installation of additional fuel pumps - this is not only a benefit for lazy pilots but has probably already prevented some accidents.

Now somebody needs to tell me why I'm flying low-wing ;)

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    $\begingroup$ Cause low wing planes look so much cooler? :) $\endgroup$
    – Jeremy Logan
    Jan 10, 2014 at 15:06
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    $\begingroup$ I guess that's it :D $\endgroup$
    – Falk
    Jan 10, 2014 at 21:57
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    $\begingroup$ Just had a thought, are there any low wing tail draggers? Hmm, I'll ask in chat. $\endgroup$
    – CGCampbell
    Jun 23, 2014 at 0:04
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    $\begingroup$ The DC-3/C-47 is a low wing tail dragger. There are others, but they are generally 1930's era aircraft. $\endgroup$
    – Skip Miller
    Jul 22, 2014 at 14:38
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    $\begingroup$ @Falk, your point about the light sport aircraft overlooks another benefit: You correctly point out that no additional pumps are required. A benefit is a lighter weight of the aircraft. This is a very important point for LSA (Light Sport Aircraft) where the weight is limited by regulation. This allows the LSA to carry more fuel. Not a lot, but every bit helps. $\endgroup$
    – Skip Miller
    Jul 22, 2014 at 14:41
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Low wing aircraft also benefit that in a crash, much of the crash energy can go into the wings instead of into the fuselage.

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Low wing aircraft have the advantage in a water landing because the wings can keep much of the fuselage above water, as well as provide a temporary staging area for deplaning passengers. In a high aircraft, you would be lucky to get out before drowning.

Likewise, on land, low wing aircraft are easier to control in a wheels up landing.

Low wing aircraft can be designed with a more widely spaced and shorter main gear, which is more stable. Most high wing aircraft use fuselage sponsons (MU2, ATR-42/72, Do228/328, BAe-146/Avro RJ, C-130) to house the main gear, providing a relatively narrow, and therefore, less stable track. For those high wing designs that house the main gear in wing-mounted engine nacelles or in the wings themselves (Twin Commander, F-27/227, Dash 7/8, B-24/32), the gear must be made much longer, and therefore, much heavier. A long main gear design is also more prone to structural failure in a hard or poorly executed crosswind landing.

Low wing aircraft are easier to refuel, and if equipped with wing-mounted engines, those would be easier to service.

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Here are a couple of ground comfort related differences.

When it's hot, and you're waiting in line for fuel, or if your plane isn't hangared, you can stand in the shade under a high wing.

If you want to walk from fore of the wing to aft of the wing, to get the oil rag you forgot, with a high wing, you duck a bit and walk straight, with a low wing, you walk all the way around the wing. Twice.

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  • $\begingroup$ My first downvote. :( I sstill think it's a good answer. $\endgroup$
    – Greg Taylor
    Dec 21, 2015 at 15:11
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    $\begingroup$ For most low wing aircraft, couldn't you climb/step on the wing? :P lol $\endgroup$
    – Anonymous Person
    May 1, 2020 at 0:35
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Another factor is fuel flow (at least in small GA planes).

Lets compare a Cessna 172 to a Piper Cherokee. The Piper is low wing and requires a fuel pump (engine driven with an electric backup) to flow the gas from the wing tanks up to the engine. This add not only adds another part that can fail but the possibility that you can vapor lock the system if you run it dry. In a the Cessna (high wing) the fuel is pulled by gravity, out of the wing tanks, and into the engine much like an old car (1930's era). This eliminates the fuel pump and the vapor lock issue which some people find quite nice. At this point I am well into the habit of switching tanks every 30 minutes.

A note should be made that some Cessnas (from what I have read) do have fuel pumps now but I don't fly them so I don't know a lot about the newer model specifics.

High wing airplanes also prove to be advantageous if you are flying a lot of back country stuff. The added clearance can help you land in bushy areas or other less hospitable places where a low wing plane might strike something.

The best answer to this question can usually be found at your local airfield. Ask a guy that owns a Piper (just not a Cub), then ask a guy that owns a Cessna (just not the 400), and decide for your self based on their answers.

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  • $\begingroup$ On the other hand, aircraft with gravity-fed fuelsystems can't fly inverted without the engine dying. $\endgroup$
    – Vikki
    May 2, 2018 at 3:03
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    $\begingroup$ @Sean very true, for that matter most tanks are gravity fed to at least their low point (and then it may be pumped higher) making most standard fuel systems improper for inverted flight. $\endgroup$
    – Dave
    May 2, 2018 at 4:28
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Another factor with low-wings is that on take off and landing, the low wing will block airflow over the empennage, reducing rudder and elevator effectiveness. That's why so many low-wings have T-tails, to keep the tail in the flow of air during landing and takeoff.

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  • $\begingroup$ This is true not just of takeoff and landing but of any higher-AoA situation, for what it's worth. $\endgroup$
    – egid
    Nov 25, 2014 at 0:25
  • $\begingroup$ yes! hopefully you're not flying high-AOA during other flight regimes, except for training $\endgroup$
    – rbp
    Nov 26, 2014 at 13:14
  • $\begingroup$ why is this worse with a low wing than a high wing? $\endgroup$
    – Peter
    Nov 27, 2014 at 1:04
  • $\begingroup$ because in a high wing, the airflow at high AOA is above the wing. in a low wing, the wing blocks the airflow to the tail: upload.wikimedia.org/wikipedia/commons/2/24/… $\endgroup$
    – rbp
    Dec 1, 2014 at 18:06
  • $\begingroup$ i know these pictures aren't perfect, but they give you an idea: airport-data.com/images/aircraft/small/000/255/255722.jpg Here's a T-Tail arrow departing (start at 40 seconds -- youtube.com/watch?v=cbzhaSp-MEs) $\endgroup$
    – rbp
    Dec 1, 2014 at 18:10
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A quick addition to the previous answers:

Larger commercial aircraft also capitalize on the low-wing's benefits from a maintenance perspective.

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    $\begingroup$ Large commercial aircraft have low wings to stow away their long landing gears. Long gears make it possible to stretch the fuselage and still be able to rotate during take-off. Large high-wing aircraft with their low fuselage position are easier to load and unload, at the price that the fuselage taper has to start shortly aft of the landing gear, so no stretching is possible. $\endgroup$
    – Peter Kämpf
    Jul 21, 2014 at 20:11
  • $\begingroup$ @PeterKämpf, are there advantages of high-wing in terms of lift versus drag (aerodynamic efficiency) performance? $\endgroup$
    – Jonny
    Apr 27, 2015 at 7:17
  • $\begingroup$ @Jonny: The best is a mid-wing configuration. High wings have less dihedral, so less lift is lost as side force. But the difference is small. If you want to know more, why not post a new question here? $\endgroup$
    – Peter Kämpf
    Apr 27, 2015 at 12:13
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Let me add one more advantage/disadvantage pair.

High-wing aircraft (at least for small GA aircraft) may be easier to preflight as wing fuel drains are more accessible and it is easier to examine the underside of the wing (flap linkages, aileron hinges, skin, possible fuel leakages). Personally, I'm tall enough to be able to see the top of the wing without a ladder, but I'll admit that this advantage shrinks for shorter pilots. The downside is ease of refueling (and sticking the fuel tanks). A Cherokee (low-wing) doesn't require a ladder to refuel whereas we carry a stepladder in our club Cessnas.

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    $\begingroup$ Another advantage of low wing over high wing is that I've never bashed my head on a low wing. $\endgroup$
    – jamesqf
    Mar 14, 2015 at 5:03

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