Aces High Bulletin Board

General Forums => Aircraft and Vehicles => Topic started by: Serenity on May 09, 2007, 09:39:52 PM

Title: 'Fowler' flaps?
Post by: Serenity on May 09, 2007, 09:39:52 PM

I know the P-38 has them, and I hear about them a lot, but I have no clue as to what they are. Anyone willing to fill me in?

Title: 'Fowler' flaps?
Post by: Blooz on May 09, 2007, 09:57:32 PM

That reminds me.

Got to post in the bug forums about the broken 'search' button.

Title: 'Fowler' flaps?
Post by: Serenity on May 09, 2007, 09:59:32 PM

Quote

Originally posted by Blooz
That reminds me.

Got to post in the bug forums about the broken 'search' button.

theres about 1,000 mentions of it, and id rather not know than spend the next 48 hours of my life sifting through posts that really dont describe what im looking for.

Title: 'Fowler' flaps?
Post by: dtango on May 09, 2007, 10:35:12 PM

http://www.centennialofflight.gov/essay/Theories_of_Flight/Devices/TH17G5.htm

From the Centennial of Flight website: "A Fowler flap (figure (a)) is hinged so that it can move back and increase the airplane's wing area. It may also be rotated down to increase the camber."

(http://www.centennialofflight.gov/essay/Theories_of_Flight/Devices/TH17G5.jpg)

Tango, XO
412th FS Braunco Mustangs

Title: 'Fowler' flaps?
Post by: Serenity on May 09, 2007, 10:36:26 PM

Thank you!

Title: 'Fowler' flaps?
Post by: Bodhi on May 09, 2007, 10:42:28 PM

This shows a good representation on most flap types in use....

(http://www.auf.asn.au/groundschool/flap_types1.jpg)

Title: 'Fowler' flaps?
Post by: Serenity on May 09, 2007, 10:47:47 PM

Ah! Thank you! The glider I fly has slotted flaps I guess, though MAYBE fowlers... this is very useful, thank you!

Title: Re: 'Fowler' flaps?
Post by: 1K3 on May 09, 2007, 10:48:34 PM

Quote

Originally posted by Serenity
I know the P-38 has them, and I hear about them a lot, but I have no clue as to what they are. Anyone willing to fill me in?

fowler flaps

increases wing area
generate lift without creating drag (?)
ideal as manuver flaps

Japanese Army planes (Ki-43, Ki-84)  and P-38s used this feature.

Title: 'Fowler' flaps?
Post by: Knegel on May 10, 2007, 02:42:50 AM

Hi,

also the fowlerflaps increased the drag, the main different is: The normal flaps have a bad airfoil as result and the part of the wings outside the flaps use a other AOA, as result wings with "normal" flaps dont create much more lift in general, but shift the stallspeed to a lower value. Fowler flaps, specialy in the manouver flap position, increase the wingarea and keep the AoA of the whole wing rather constant, as result the lift realy increase and so more tight turns can be flown, though for the price of a higher E-bleed.

The only way to create more lift, without more drag is to increase the wing aspect ratio(with same wingarea), but even this only count for speeds when mach related problems dont matter.  

Otherwise more lift = more drag.

Greetings,

Knegel

Title: 'Fowler' flaps?
Post by: Benny Moore on May 10, 2007, 07:44:28 AM

Right, Fowlers have a lot more lift for the same amount of drag other flap types have.  Fowlers are something like 20 or 30% more efficient than conventional flap types.