Quantcast

Wittman Tailwind modified to meet E-LSA?

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

TFF

Well-Known Member
Joined
Apr 28, 2010
Messages
13,614
Location
Memphis, TN
CAFE did the same thing, prop off gliding, on a C150 to verify their method of zero thrust tests for the CAFE testing.
 

arp67

Member
Joined
Aug 31, 2010
Messages
11
Location
Fresno, CA
After some more thought, I think it might be easier to build a Cub look-a-like (Wag Aero Sport Trainer) and customize it with Wittman Tailwind design elements (windshield, tailfeathers, Wittman style landing gear). I love the cowling used on most of the W-10s with Lycoming engines, don't know how to make a cowling like that work on the front of a J-3 style fuse/firewall?
 

cluttonfred

Well-Known Member
HBA Supporter
Joined
Feb 13, 2010
Messages
7,664
Location
Fort Walton Beach, Florida, USA
Nope, just plugged the gross weight, clean CL max, and aspect ratio into my LAA performance estimation spreadsheet and tweaked the desired stall speed until the span and area came out right. I don't claim to have anywhere near the knowledge or experience of someone like Steve Wittman, but I do look at claims of fuselage lift with skepticism. Time and time again, actual calibrated testing has shown unexpectedly low stall speeds to be measurement errors related to the high angle of attack messing with a fixed pitot tube.

I don’t know if any actual testing has been done to verify it, but Witt claimed that the fuselage produced a significant amount of lift. Did you allow for that in your analysis?
 

samyguy

Well-Known Member
Joined
Sep 19, 2011
Messages
118
Location
Lincoln Nebr
OK I may regret this. I have W-10 that will meet LSA.
Empty weight 593# wing span 27.5 ft. wittman tips.
A75 motor
Calbie Woods Al. wings, And much correspondence between Steve W. and the builder.
.250th cuff under leading edge. Guy built 3 sets of wings to get it right.
Stall 44 mph top 130 mph
N847WL
 

TFF

Well-Known Member
Joined
Apr 28, 2010
Messages
13,614
Location
Memphis, TN
What you have is exactly what is needed to do it, as discussed. Very light, 325 lbs lighter than the normal W10; very close to original. Small engine. Bigger wing with airfoil mods, and the Calbie wing is probably stronger to make it longer. You do come to the question, what is in a name?

One of the things I love about the Regular Tailwind is the wood wing. It’s actually why I don’t want to build Calbie’s Four Runner. I even thought of a clipped wing Bearhawk as I would rather have the speed. I want the slick ply covered wing like a Bellanca or wood wing Mooney.
 
Last edited by a moderator:

Mcmark

Well-Known Member
Joined
Sep 24, 2013
Messages
396
Location
Owings, MD
Tiger Tim that is the Butter Burger built by Jim Clements. Mostly ButterCup but no leading edge “cuff/flap” and some other changes.
He has also built one with a Tailwind size fuselage and 2 strut per wing with a 290 that meets LSA weight and stall but it’s not a Tailwind. It’s still too fast in cruise.
Ask him!
 

Turd Ferguson

Well-Known Member
Joined
Mar 13, 2008
Messages
5,277
Location
Upper midwest in a house
customize it with Wittman Tailwind design elements (windshield, tailfeathers, Wittman style landing gear). I love the cowling used on most of the W-10s with Lycoming engines, don't know how to make a cowling like that work on the front of a J-3 style fuse/firewall?
Tim Buttles has more champ than cub in his plane but he used flat plexi panels for the windshield. Not to be like a tailwind but because it's $$$ cheaper than a molded windshield. Square off the tail, which I've seen cub clones with squared tail feathers. The pressure cowl is there so add tapered rod gear and you're
good to go!
huskychaser.jpg
 

BJC

Well-Known Member
HBA Supporter
Joined
Oct 7, 2013
Messages
11,742
Location
97FL, Florida, USA
That’s a neat aiirplane that I never have seen. Thanks, Turd.

Did he consider a flat-wraled windshield?


BJC
 

cluttonfred

Well-Known Member
HBA Supporter
Joined
Feb 13, 2010
Messages
7,664
Location
Fort Walton Beach, Florida, USA
The Daphne is a great example of what it takes to make an LSA out of a Tailwind: 55% more wing area and a 33% thicker airfoil implemented with an entirely different wing and strut structure. All that's left is the Tailwind look, which is not a bad thing if that's what you like and LSA is the mission you have to fulfill. Here's an article on a Daphne from 1966.

yea its called the Szaraz Daphne
A Tailwind W8 fuselage with Stits Skycoupe wings
 

Attachments

Michael Silvius

Well-Known Member
Joined
Jan 26, 2020
Messages
62
Location
Maine USA
The Daphne is a great example of what it takes to make an LSA out of a Tailwind: 55% more wing area and a 33% thicker airfoil implemented with an entirely different wing and strut structure. All that's left is the Tailwind look, which is not a bad thing if that's what you like and LSA is the mission you have to fulfill. Here's an article on a Daphne from 1966.
Yea whats not to like about it for us sub-farts getting a bit long in the tooth? That Sky-Coupe wing with a 35 kt stall should make for nice docile handling. I was fortunate to score a set of plans for it on E-bay a couple years ago.
  • Length: 19 ft 7 in (5.97 m)
  • Wingspan: 26 ft (7.9 m)
  • Wing area: 130 sq ft (12 m2)
  • Airfoil: NACA 4412
  • Empty weight: 820 lb (372 kg)
  • Gross weight: 1,300 lb (590 kg)
  • Maximum speed: 130 kn (150 mph, 240 km/h)
  • Cruise speed: 100 kn (120 mph, 190 km/h)
  • Stall speed: 35 kn (40 mph, 64 km/h)
  • Never exceed speed: 150 kn (170 mph, 270 km/h)
 

stanislavz

Well-Known Member
HBA Supporter
Joined
Aug 21, 2016
Messages
632
Location
Lt
Sadly it was destroyed a couple years ago.
I think it is in restoration now ?

But back to topic :
1600262505209.png

It as a example from aerodynamic book on how to minimize interference drag - square and straight fuselage under the wing, and only after wing there is some "natural lines" Same on top - natural bend lines. Did made an thread on ol' ironside in carbon.

Was it a Tailwind - now, was it inspired by it - yes.
 
Last edited:

Latest posts

Top