Re: High wing vs. low wing

Date:         16 May 2001 17:45:26 
From:         jthorn@galileo.thp.univie.ac.at (Jonathan Thornburg)
Organization: Universitaet Wien (Vienna, Austria) / Institut fuer Theoretische Physik
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In article <airliners.2001.159@ditka.Chicago.COM>,
JP Caputa  <jcaputa@engr.uvic.ca> wrote:
>WHAT ARE THE BENEFITS OF LOW WINGED AIRCRAFT (if any) AS OPPOSED TO HIGH
>WINGED AIRCRAFT?

+ more ground effect --> shorter takeoff/landing distances and/or
                     --> higher maximum takeoff gross weights
+ wing-mounted engines lower to the ground --> easier servicing
+ fuel tanks in wings are lower to the ground --> easier refueling
+ wing-mounted landing gear needs shorter struts --> stronger/lighter

Of course, there are drawbacks, too:
- wing-mounted engines may be *too* close to the ground
  --> risk of foreign-object damage if unpaved runways are used
      (though the 737 was certified for gravel runways)
  --> max bank angle on landing ( ==> max crosswind for landing)
      might be limited by nacelles hitting the ground instead of
      wingtips hitting the ground (dihedral alleviates wintip-hitting)
- more risk of ground servicing vehicles hitting/damaging wings/engines

As the original poster noted, empirically low-wing wins for civilian use.

--
-- Jonathan Thornburg <jthorn@thp.univie.ac.at>
   http://www.thp.univie.ac.at/~jthorn/home.html
   Universitaet Wien (Vienna, Austria) / Institut fuer Theoretische Physik
     Only 6 countries in the world have the death penalty for children:
     Congo, Iran, Nigeria, (Pakistan[*]), Saudi Arabia, United States, Yemen
     [*] Pakistan reportedly ended it in July 2000. -- Amnesty International
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