Author Topic: P-47 Profile Stunter (Read 7843 times)

pat king · « **on:** March 20, 2016, 10:25:05 AM »

This airplane is based on the P-47 Stunter designed by Bill Werwage. It has an improved wing size as recommended by Chris Rud. The wing has 2” less span and 3/4” more chord. The airplane has a 61 1/8” span and 719 square inches of wing area. The airplane is designed for .60 to .67 size engines. The laser cut kit comes with full size CAD plans that have full size templates of all parts. The kit does not include any control system hardware. If you would like a less expensive profile version of a World Championship airplane then this one is for you. The first kits will sell for $245.00 plus shipping for a 6 X 6 X 36 box weighing 5 pounds from zip 60449

Pat

The price went up. I underestimated the cost of these kits.

wwwarbird · « **Reply #1 on:** March 20, 2016, 08:13:47 PM »

Another great offering Pat, if I could only have the time to build everything I'd like to.

One thing I notice every time but can't figure out, why is it that no one ever gets the wingtip outline anywhere near right with the P-47 designs? I know we're not building scale here but...

pat king · « **Reply #2 on:** March 20, 2016, 10:47:29 PM »

Wayne,
The tips match the Werwage P-47. I don't know why they are not the same shape as the full scale airplane. The tips on my 1/2A P-47 are scale.

Pat

Allan Perret · « **Reply #3 on:** March 21, 2016, 07:17:06 AM »

Do you sell just the plans ?

pat king · « **Reply #4 on:** March 21, 2016, 11:37:48 AM »

Allan,
Full size .pdf files of any of my airplane plans are $5.00 delivered to your inbox.

Pat

wwwarbird · « **Reply #5 on:** March 21, 2016, 08:57:41 PM »

Quote from: pat king on March 20, 2016, 10:47:29 PM

Wayne,
The tips match the Werwage P-47. I don't know why they are not the same shape as the full scale airplane. The tips on my 1/2A P-47 are scale.

Pat

Yup, I'd noticed that too, just thinkin' out loud.

pat king · « **Reply #6 on:** March 22, 2016, 08:07:54 AM »

Admit it. You just like to rattle my cage to get my reaction.

Pat

Allan Perret · « **Reply #7 on:** March 22, 2016, 04:32:19 PM »

Quote from: pat king on March 20, 2016, 10:25:05 AM

This airplane is based on the P-47 Stunter designed by Bill Werwage. It has an improved wing size as recommended by Chris Rud. The wing has 2” less span and 3/4” more chord. The airplane has a 61 1/8” span and 719 square inches of wing area. The airplane is designed for .60 to .67 size engines. The laser cut kit comes with full size CAD plans that have full size templates of all parts. The kit does not include any control system hardware. If you would like a less expensive profile version of a World Championship airplane then this one is for you. The first kits will sell for $190.00 plus shipping.

Pat

Does it have the same tail volume as Billy's design ?

pat king · « **Reply #8 on:** March 22, 2016, 09:37:29 PM »

Quote from: Allan Perret on March 22, 2016, 04:32:19 PM

Does it have the same tail volume as Billy's design ?

The shapes of the empennage are lifted out of the files for the P-47 that Chris Rud is selling as Werwage and Son. Other than the wing span and chord the all the shapes are from the files for the built-up stunter. If the chord on the ribs is scaled to match the built-up stunter the rib profiles are no more .015" off of the rib shapes of the built-up stunter.

Pat

pat king · « **Reply #9 on:** March 23, 2016, 11:16:38 AM »

Allan,
If you are asking about the Tail Volume Coefficient, as calculated by the following formula:
Tail Volume Coefficient
Tail Volume = (Tail Area/Wing Area) X ( Tail Arm/Wing Avg. Chord) where:
Tail Area = area of the horizontal stabilizer
Wing Area = area of the wing
[both areas include that encased by/covered by the fuselage]
Tail Arm = distance from LE of wing to LE of stab [for untapered surfaces; for tapered, use LEs at average chord]
Wing Avg. Chord = area / wing span
Billy's airplane TVo = 0.24131
The profile airplane TVo = 0.22465

Pat

Mark Scarborough · « **Reply #10 on:** March 23, 2016, 11:32:37 AM »

Pat are you sure about that, typicall stunt TVC numbers are closer to .4-.5

pat king · « **Reply #11 on:** March 23, 2016, 12:49:08 PM »

Quote from: Mark Scarborough on March 23, 2016, 11:32:37 AM

Pat are you sure about that, typicall stunt TVC numbers are closer to .4-.5

Mark,
The formula uses the area of the horizontal stabilizer. If the same calculation is run using the area of the entire horizontal tail the numbers would be larger. The number for the profile airplane is .39247 if the calculation uses all of the horizontal tail.

Pat

Mark Scarborough · « **Reply #12 on:** March 23, 2016, 02:54:13 PM »

Pat,
respectfully, The formula as I was taught is defined differently

the Horizontal stab area by definition INCLUDES the elevators

the second portion is

(the distance from the CG to the center of the stab[what you call the tail arm]) divided by the MAC

wwwarbird · « **Reply #13 on:** March 23, 2016, 06:00:52 PM »

I just stick to the eyeball and tape measure formulas.

Walter Hicks · « **Reply #14 on:** March 23, 2016, 07:58:53 PM »

Mark, hold on you will see this plane in action it will have one of my K 77 engines in it

pat king · « **Reply #15 on:** March 23, 2016, 08:46:24 PM »

Quote from: Mark Scarborough on March 23, 2016, 02:54:13 PM

Pat,
respectfully, The formula as I was taught is defined differently

the Horizontal stab area by definition INCLUDES the elevators

the second portion is

(the distance from the CG to the center of the stab[what you call the tail arm]) divided by the MAC

Mark,
I was not taught any formula for tail volume coefficient because I am a Mechanical Engineer, not an Aeronautical Engineer. When I searched for a method to calculate Tail Volume Coefficient I found several formulae. I will re calculate when I get a chance. Right now I have to do some reading, investigation, then write a proposal for a potential client. The design consulting takes precedence over airplane or boat design.

Thanks, Pat

Mark Scarborough · « **Reply #16 on:** March 23, 2016, 10:03:45 PM »

Quote from: pat king on March 23, 2016, 08:46:24 PM

Mark,
I was not taught any formula for tail volume coefficient because I am a Mechanical Engineer, not an Aeronautical Engineer. When I searched for a method to calculate Tail Volume Coefficient I found several formulae. I will re calculate when I get a chance. Right now I have to do some reading, investigation, then write a proposal for a potential client. The design consulting takes precedence over airplane or boat design.

Thanks, Pat

Hey Pat, hope you understand I am just trying to be helpfull, a TVC of .220 with flaps is pretty meager so it made me wonder, especially when you calculated Billy's at .240,, mOst modern designs are above .450 . I was shown this by Pat Johnston and others. there is some relevant discussion on here if you do a search for "TVC"
Walter, I look forward to seeing it with a High zoot engine in it,,

pat king · « **Reply #17 on:** March 24, 2016, 08:32:36 AM »

Mark,
No offense taken. As I am not an Aero E I don't know about such things. I will do the constructions and calcs before the weekend is over.

Thanks, Pat

pat king · « **Reply #18 on:** September 21, 2017, 01:07:04 PM »

Bumping this up to help answer a question.

Author Topic: P-47 Profile Stunter (Read 7843 times)

pat king

P-47 Profile Stunter

wwwarbird

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter

Allan Perret

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter

wwwarbird

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter

Allan Perret

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter

Mark Scarborough

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter

Mark Scarborough

Re: P-47 Profile Stunter

wwwarbird

Re: P-47 Profile Stunter

Walter Hicks

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter

Mark Scarborough

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter

pat king

Re: P-47 Profile Stunter