Taylorcraft wing airfoil

[Miguel]

I was surprised when I was ablr to check how many planes use the same wing airfoil NACA 23012 from our Taylorcraft B models, both in the USA and in other countries.

I pass a list of the planes

BEECHCRAFT 17
HELIO COURIER
AERO COMMANDER 500, 520, 580, 600, 680, 720
MURPHY RENEGADE
BEAGLE A115, TERRIER, AIREDALE (UK)
BRITTEN NORMAN ISLANDER & TRISLANDER (UkK
DRUINE TURBULENT (UK)
JODEL DR 1050 (FRANCE)
JURCA TEMPEST (FRANCE)
MUDRY CAP-10 (FRANCE)
PIEL EMERADUDE, DIAMANT, BERYL (FRANCE)
AERO BOERO 115, 150, 180, 210, 260 (ARGENTINE)
,
It is possible that may be others models that also use the same airfoil.

I hope you be as surprised as I am!

Miguel.-

[PA1195]

The wing is popular as it's efficient in cruise. It doesn't require lots of trim changes. When lift enhancements like flaps or leading edge devices are added it can fly fast - slow - and carry a range of loads across a wide CG envelope. Most commercial applications have those enhancements.

Here's a list: https://m-selig.ae.illinois.edu/ads/aircraft.html

Gary

[Miguel]

On this same page I found that information!!! Thanks.-
Miguel.-

[astjp2]

It does have a pitching problem if there is no washout, it likes to nose over a lot and the flaps per NACA should be a USA35B airfoil with 12% of wing chord.

[Bigdog]

If you expand it to other thicknesses you'll find a huge number using the 23000 series airfoil, including the Corsair. BTW the "12" in 23012 is the thickness, 12%.

[PA1195]

Cessna did lots of mods to keep their variable thickness 23000 series stall speed under 61 knots. Leading edge enhancements that includes a variety of VG's and a couple types of trailing edge Gurney flaps and dedicated slot.

For the Taylorcraft VG's are available and quick install Gurney flaps might be interesting. There's studies that support their installation on that airfoil. http://www.dept.aoe.vt.edu/~mason/Ma...A2007-4175.pdf

Gary

[otrcman]

Gary,

I wasn't aware that Cessna had experimented with 23000 series airfoils, and especially that the played with VG's and slots. Can you send me a reference ?

Thanks, Dick

[PA1195]

Gary,

I wasn't aware that Cessna had experimented with 23000 series airfoils, and especially that the played with VG's and slots. Can you send me a reference ?

Thanks, Dick

Hi Dick nice to meet you. If you look here/linked above ( https://m-selig.ae.illinois.edu/ads/aircraft.html) under Cessna aircraft you'll see several with variations on the 23000 series. It appears the wing thicknesss and typically taper was a blended variation from root to tip. Not surprising if spar and wing support was needed at the fuselage juncture and wash at the tip (how much?) took care of the spanwise flow separation.

The 23012 is quite similar to their traditional 2412 - comparative plots are available here > http://airfoiltools.com You can overlay both airfoils and compare parameters at various Reynolds Numbers.

As far as a Caravan there are several locally used for Part 135 ops and I drive by almost daily. The LE enhancements I've seen have been VG's of various size and spacing (depends on if it has a rubber booted or wet weep wing) and a LE generator forward of the aileron and flap junction (https://support.cessna.com/custsupt/...df?as_id=33995).

They used Gurney flaps on a portion of the outboard flaps (one traditional and sometimes by model one adjacent that's scalloped) plus a dedicated slot forward of the Gurney flapped portion behind the wing spoilers. There's no LE slot and I wasn't clear above about that. Edit: They also add VG's to the upper rear of the horizontal stabilizer to help flow behind and I assume adequate nose down authority from the elevator. I've read they can loose same during icing conditions.

I still believe a Taylorcraft with a properly designed flap like Interstate Arctic tern used would be an asset. http://www.interstateaircraft.com

Gary

[astjp2]

So Gary, do you not like the F-21 flaps?

[PA1195]

I have no experience with them Tim so have no opinion. Below are pics of Taylorcraft's hinge line setup (2nd pic). Basically ailerons with aileron hinges with outboard bottom extensions and supports that create a larger rollback arc that opens a forward slot. On Pre-War wings there's no similar open rear cove to the aileron but it appears Taylorcraft added one to the flap bay to direct air through the slot. Depending on seal at the top between the flap and wing I'd want one like Piper added to the Cubs (PA-14/18) to direct flow aft some over the leading edge. There's NACA/NASA studies on how to optimize that flow and gap on 23012 airfoils.

Arctic Tern uses a different approach to hinge line and flaps (first pic). It's airfoil design is available in Abott and Doenhoff's Theory of Wing Sections flap design p. 212 2-H I believe. The hinge is more aft on the flap which swings down and back perhaps more than the Taylorcraft design.

Either would be better than nothing as 4-5 mph lower stall and a nose down attitude at the same or increased C/L with drag as needed would be a fun tool.

Gary

[astjp2]

Hey Gary, any chance you can grab some measurements of the arctic tern flap mounts? Something like length behind the spar and the amount it hangs below the flap? Also the flap length? I don't have access to any here and I am playing with a homebuilt project that flaps may be beneficial to.

[PA1195]

Yes Tim I can but I suspect the angles and dangles would not be appreciably better than the Taylorcraft hinge design I linked above. It's far simpler to modify the hinge on an aileron and move the hinge line and torque supports down on the aileron brackets to meet the second pic above. Adding a Piper upper gap fairing is critical versus any Taylorcraft design without. Implementation of deflection could be via an aileron bellcrank and intensive cabling, or a simple cross-fuselage tube connected to the end of the flaps. Flap torsion under air load is a consideration outboard of that. Then simply run a cable to an overhead lever that pulls an eccentric on the cross tube to deflect the flaps. Retraction is via appropriate springs. My theory so far.

Slips gets us down but unlike flaps at no increased lift only drag. Then we correct the slip and speed can increase. I have many thousands of hours in flapped planes and never had to slip...just lower flaps and establish a stabilized landing configuration to the ground. And takeoffs are shortened.

Gurney flaps might help too at far lower expense and effort.

Gary

[PA1195]

Lowered rear spar and Gurneys. Cub gear to add a frosting.

Gary

[astjp2]

For a home built, I can build my own brackets. Just need to figure out where to put the hinge pins. Even if I get a location of the pin from the trailing edge of the flap and the amount it sits below it, I can lay it out in cad. What is interesting is how the pre and post war airplanes aileron coves changed but they both had the leading edges of the ailerons tip up above the wings to counter adverse yaw. This is just an idea for my home built that I am thinking about finishing someday. I have a tandem fuselage and engine mount already on the gear, I would just need to build tail feathers and wings. I am thinking that 80 gallons of gas and an o-200 would give 10 hours of range and 900 miles. 450 out and back. Or an o-320 with a turbo sink could stay at 17.9 for 8 hours would be one hell of a short field long range airplane.

[Jim Herpst]

Also the original RV series. RV 4,RV3 RV6 RV8 all use the airfoil. In fact Richard apparently was amazed as a teenager flying both a Cub and A Taylorcraft off the family farm how much faster the Taylorcraft was!......