Go Back  RCU Forums > RC Airplanes > Aerodynamics
Reload this Page >

Low wing design faster than a high wing design?

Notices
Aerodynamics Discuss the physics of flight revolving around the aerodynamics and design of aircraft.

Low wing design faster than a high wing design?

Old 11-05-2005, 10:29 AM
  #1  
gemarl
Junior Member
Thread Starter
 
Join Date: Sep 2004
Location: Alpharetta, GA
Posts: 25
Likes: 0
Received 0 Likes on 0 Posts
Default Low wing design faster than a high wing design?

A co-worker of mine told me that he heard that people were going to low wing designs because they were faster than high wing designs. Has anyone every heard of this?

I thought this was rediculouse, of course. But if you think of it there has to be some difference if the fuselage is in low pressure air on low wing designs instead of in high pressure air in high wing designs.

Gemarl
Old 11-05-2005, 12:17 PM
  #2  
flyswatter
Senior Member
 
flyswatter's Avatar
 
Join Date: Feb 2004
Location: St. Simons Island, GA
Posts: 516
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

I agree with you. I have a hard time believing that low wing designs are faster. I can not think of any reason it would be true. I believe the main reason fighters (for example) began using a low wing design was not for increasing speed, but for rear visibility and to help keep an enemy from sneaking up in the pilot's high, blind spot. Note how current fighters use shoulder wings with the canopy mounted at the same position forward of the sweep. I do not believe they are giving up speed with that design.
Old 11-05-2005, 02:27 PM
  #3  
rmh
Senior Member
 
rmh's Avatar
 
Join Date: Dec 2001
Location: , UT
Posts: 12,630
Likes: 0
Received 2 Likes on 2 Posts
Default RE: Low wing design faster than a high wing design?

forward visibility better than mid wing plus retract landing gear shorter -- big items
structurally a mid wing setup is usually best -common on light homebuilt racers
Old 11-05-2005, 03:25 PM
  #4  
BMatthews
 
BMatthews's Avatar
 
Join Date: Oct 2002
Location: Chilliwack, BC, CANADA
Posts: 12,422
Likes: 0
Received 22 Likes on 19 Posts
Default RE: Low wing design faster than a high wing design?

Yep, complete balderdash. Your buddy is probably caught up in the idea because many of the faster designs from the war were low wingers. But that was often for other reasons.

Low wings offer not only the better viz as mentioned but also an undisturbed path for wing spar carry through structures. And the landing gear issue as well. Look at the old Wildcat that used fuselage mounted gear to keep it short and how they went to the wing gear with the next designs. All the info I've read about the Corsair mentions the advantage of shortening the main gear as a major reason for the inverted gull wing.
Old 11-05-2005, 06:45 PM
  #5  
e=mc2
Member
 
Join Date: Aug 2003
Location: Omaha, NE
Posts: 70
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

The high wing design allows for uninterrupted flow over the wing near the root. In a low wing that flow near the root of the wing is often disturbed by the fuselage. This allows for high wing aircraft to have lesser interference drag compared to the low wingers. However, interference drag can be (and has been) easily combatted by appropriate fillets and extended trailing edge near the fuselage.

Any interference drag reduction of high wing might be offset by the higher downwash on the tail increasing the drag due to having to maintain a larger down force on the tail.

Maybe that is why the structural benefits, better thrust line alignment and better combat visibility of the low wing might have been favored.

Cheerios!
e=mc2
Old 11-05-2005, 07:10 PM
  #6  
combatpigg
Senior Member
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,018
Received 7 Likes on 7 Posts
Default RE: Low wing design faster than a high wing design?

Do right side up passes, then inverted passes [that are clocked] to see what the difference is with a plane that has a symetrical airfoil. I'll bet the results will be inconclusive. A high wing model speed plane, [with no landing gear] is my favorite set up for practicality. I think the low CG improves smoothness and aides fine control, which should contribute to the shortest distance travelled between 2 points.
Old 11-05-2005, 09:23 PM
  #7  
gemarl
Junior Member
Thread Starter
 
Join Date: Sep 2004
Location: Alpharetta, GA
Posts: 25
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

ORIGINAL: e=mc2

Any interference drag reduction of high wing might be offset by the higher downwash on the tail increasing the drag due to having to maintain a larger down force on the tail.
e-mc2,

In that case would a high wing and T-tail be a better combo for speed?

Gemarl
Old 11-06-2005, 02:05 AM
  #8  
former spad
Senior Member
 
Join Date: Nov 2004
Location: Mission Viejo, CA
Posts: 146
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

I got a back seat ride in a P-51D several years ago. The visibility was way, way better than any of the larger single engine Cessnas I had flown in. Especially important when the ground and sky get mixed up during aerobatics. I assume in the days of kill or be killed, visibility would be far more important than any possible slight aerodynamic advantage of high wing.
Old 11-07-2005, 04:35 PM
  #9  
Tim Wiltse-RCU
Senior Member
 
Tim Wiltse-RCU's Avatar
 
Join Date: May 2003
Location: Concord, NC,
Posts: 2,494
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

Didn't the fact that alot offighters were low wing also due to the need to get the fuse in the air so they had ground clearance for those huge props? That was the reason behind the reverse gull wing on the Corsair right?

Later,
Tim
Old 11-07-2005, 08:53 PM
  #10  
combatpigg
Senior Member
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 20,018
Received 7 Likes on 7 Posts
Default RE: Low wing design faster than a high wing design?

Good point, TIM. Lots of guys back then still found ways to bend those props up. I'll bet those dynamic soaring guys, especially the ones who developed their sport to what it is today, could weigh in here with what has been tried and with what has been learned.
Old 11-07-2005, 08:54 PM
  #11  
gemarl
Junior Member
Thread Starter
 
Join Date: Sep 2004
Location: Alpharetta, GA
Posts: 25
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

ORIGINAL: Tim Wiltse-RCU

Didn't the fact that alot offighters were low wing also due to the need to get the fuse in the air so they had ground clearance for those huge props? That was the reason behind the reverse gull wing on the Corsair right?

Later,
Tim
It makes sense and I understand the advantage in maneuverability and visibility for low wing aircraft. But what I really want to know is: Is it faster??? Why or why not? Is it not true that a the air above the wing has less pressure, therefore, the fuselage in this air would feel less drag? Or might there be some other unforeseen consequence of the airflow before and after the wing that might make it more draggy?
Old 11-07-2005, 10:24 PM
  #12  
former spad
Senior Member
 
Join Date: Nov 2004
Location: Mission Viejo, CA
Posts: 146
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

Looking at the latest designs of full size experimental aircraft used to race at Reno, all are low wing. I can't remember seeing any high wing designs. My guess is that minimizing drag is much more complex than wing placement alone. There are threads to sites that explain aerodynamics at the top of this forum that may have some answers.
Old 11-07-2005, 10:37 PM
  #13  
js3
Senior Member
My Feedback: (3)
 
Join Date: Jan 2002
Location: Arvada, CO
Posts: 1,260
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?


ORIGINAL: former spad

Looking at the latest designs of full size experimental aircraft used to race at Reno, all are low wing. I can't remember seeing any high wing designs. My guess is that minimizing drag is much more complex than wing placement alone. There are threads to sites that explain aerodynamics at the top of this forum that may have some answers.
Check again. The formula 1 planes are mostly mid wing aircraft. Of course the unlimited (fastest) racers are low wingers because they start with a fighter to begin with. Look at John Sharp's Nemesis. Pretty much unbeatable and it is a mid wing design.
Old 11-08-2005, 12:05 AM
  #14  
former spad
Senior Member
 
Join Date: Nov 2004
Location: Mission Viejo, CA
Posts: 146
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

You're right, wife came home upset and distracted me in middle of post. I was thinking about mentioning the formula one planes, but I forgot. I suspect they illustrate symmetrical designs are most efficient.
Old 11-08-2005, 05:29 PM
  #15  
e=mc2
Member
 
Join Date: Aug 2003
Location: Omaha, NE
Posts: 70
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?


ORIGINAL: gemarl

e-mc2,

In that case would a high wing and T-tail be a better combo for speed?

Gemarl

gemarl,

In theory I guess that is true, but practically... not so. A high will will need to have an even higher horizontal stab. The weight added plus the offset with the thrust line would be too difficult and probably not worth it for a practical design.

e=mc2
Old 11-08-2005, 08:28 PM
  #16  
davidfee
Senior Member
 
Join Date: Jun 2003
Location: San Diego, CA
Posts: 691
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Low wing design faster than a high wing design?

The fastest electric pylon models are shoulder/high wing with T-tails. There are a lot of practicality/manufacturing/structural issues that determine what aircraft look like. You can't always build the airplane you'd like at a weight/durability you can live with.

-David

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2022 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.