Avions Fairey (Tipsy) Junior airfoil?

[cluttonfred]

Does anyone have a source identifying the airfoil used in the wing of the Tipsy Junior light plane by Avions Fairey in 1947?

 

[Retrofit]

From the book "Les avions Tipsy / Tipsy airplanes" by Vincent Jacobs:

Tipsy S2: RAF 48 at the root, RAF 28 at the tip.
Tipsy Nipper: NACA 43012A
Gusty Nipper: NACA 0012

 

[cluttonfred]

Thanks, I have that book, too, but I am still trying to identify the Junior airfoil in particular.

 

[cluttonfred]

Does anyone have the Putnam series Fairey Aircraft since 1915 handy? I wonder if the Tipsy types are covered in there given the Fairey connnection.

 

[Richard N]

Fairey Aircraft covers 8 Tipsy types on pages 39-44.

 

[cluttonfred]

Thanks, but I don't have that book. Can you tell me if the airfoil for the Tipsy Junior is identified?

 

[Richard N]

All it mentions about the Junior is that 2 were built. Airfoils are not mentioned for any of the aircraft in the book. What is so important about its airfoil?

 

[Richard N]

You might know this character. He was at a model flying event I went to last year.

SMALL 30th / Fall SMALL -- Oct 10-13, 2019 (Thr-Sun) -- Mayflower, Arkansas - Page 16 - RC Groups

Page 16-Fly-In SMALL 30th / Fall SMALL -- Oct 10-13, 2019 (Thr-Sun) -- Mayflower, Arkansas RC Flight Events

www.rcgroups.com

 

[cluttonfred]

I do know Eric, I have been running the site on his behalf for ten years!

On the Tipsy Junior, I am studying it from the point of view of an amateur builder, not to make a replica but to collect design tips and tricks, and the airfoil is a pretty fundamental data point.

 

[shedofdread]

IF you can get a decent (square on) photo of the aerofoil, it can be imported into XFLR5, traced and then analysed. This is an imperfect process but but in the absence of other data, it may be your best bet...?

 

[cluttonfred]

IF you can get a decent (square on) photo of the aerofoil, it can be imported into XFLR5, traced and then analysed. This is an imperfect process but but in the absence of other data, it may be your best bet...?

I only have this image of a typical wing rib reproduced from a small image in the Jacobs book. I don't have the ability to pull the data from this image, but if you or someone else does and can thereby identify the airfoil, I'd be grateful.

 

[shedofdread]

I probably won't be able to ID the aerofoil but I should be able tell you what the characteristics are and if you tell me what the operating Re value is, generate a Cl vs Cd plot. I might take a 'short while' so *usual disclaimer applies'

 

[cluttonfred]

Thanks! Wing chord is about 5.0 ft and cruising speed about 98 mph in the Walter Mikron version so the Reynolds number is about 4.7 million.

 

[Mark Nankivil]

Though the Avions Fairey Junior is not listed, this is a useful resource for airfoil types by aircraft type:

The Incomplete Guide to Airfoil Usage

Enjoy the Day! Mark

 

[shedofdread]

The camber is 2.8% and the thickness 13%. Plots to follow...

 

[cluttonfred]

Thanks, Mark, I know that site well.

Shed, I have to wonder if there might be some distortion in the image. I checked airfoiltools.com and I can't find any common 1940s or earlier airfoils very close to that camber and thickness. I did find the RAF 38 with 2.5% camber and 12.7% thickness which seems the most likely candidate.

RAF 38 AIRFOIL (raf38-il)

Details of airfoil (aerofoil)(raf38-il) RAF 38 AIRFOIL RAF-38 airfoil

airfoiltools.com

 

[shedofdread]

As promised plot attached.
tj1a is the aerofoil as traced and 1 and 2 are with a small amount of inverse design to clean the aerofoil up.

Not sure if it will upload but p2.wpa is the Xflr file. You're free to use this but obviously not for anything man-carrying, eh? edit - can't upload .wpa files - sorry.

 

[cluttonfred]

Thanks, Shed. It looks like the XFLR file did not come through but that's OK.

 

[shedofdread]

Attached is the xflr file. I've named it p3.txt - download it and change the file extension to .wpa