Author Topic: Hellcat profile plans #150! (Read 3429 times)

Pat Johnston · « **on:** July 28, 2011, 07:43:12 AM »

Here is the latest "plan of the week", a Profile Hellcat. This one is intended for 40-51 power. The LA46 would be best. Wing area is 566 inches, 54" span. The projected weight should be in the mid 40 ounce range. The fuselage uses my 1/2" foam filled interior with light 1/16" skins covering it all. The 1/16" plywood doublers are flush with the skins with a 3/8" cheek cowl on the left side. The stab and elevator are ribbed to keep the back end light. The airfoil uses an elliptical front end with the high point at 20% back. Root thickness is 18%, graduating to 16% thick at the tip. The flaps are 3/8" stock, tapered. The airfoil is altered to use this constant 3/8" thick flap. This is a lot easier to manage than building up the flaps.
Overall, this will be a top competitor in the profile class. I'll paste on PDF files for gandering purposes.
Pat Johnston
Design Studio
Skunk Works

wwwarbird · « **Reply #1 on:** July 28, 2011, 08:01:09 AM »

Great looking 'Cat Pat! A great way to celebrate the 100th anniversary of Naval Aviation.

Mark Scarborough · « **Reply #2 on:** July 28, 2011, 08:28:11 AM »

Pats 150 design,, planset, on naval aviations 100 anniversiry,, hmmm
seriously Pat,, you realize that now there is not enough time to build any of these, I spend to much time looking at the plans trying to decide which one would be cool to build next,,
I think its time for some WW2 fighter /stunt plane combat !

john e. holliday · « **Reply #3 on:** July 28, 2011, 08:39:41 AM »

Thought that was done down Texas way for the boys at the home? Thought of getting those plans as they used basically the same foam wing with different fuselage, wing tips and tail surface outlines.

Ron Merrill · « **Reply #4 on:** July 28, 2011, 09:43:04 AM »

Wow Pat, another good one, keep them coming. Sure like that fat blunt wing LE.

Ron.

Jerry Leuty · « **Reply #5 on:** July 28, 2011, 09:51:39 AM »

Do you have a catalog of your .40 to .46 size stunt planes that you've designed? I do a lot of scratch building using a fairly contemporary wing of 52" with a 1.75" root thickness and 8 to 9" cord. I have just about quit building profile planes. I recently won a Twister kit at the Ring Master Round Up this past spring in Houston and I am going to build it as a built up fuselage.........kit bashed so to speak. Don Hutchinson has several nice plans out as well for profile WW11 warbirds.

Pat Johnston · « **Reply #6 on:** July 28, 2011, 12:09:16 PM »

Jerry,
Send me an E-mail at:
pjohnston at idahopower dot com. I'll send you my latest plans list. I have a lot in the 40/46 class. Stacks of warbirds.
Doc, That Hellcat was in a 389 inch version for the speed limitted combat and youth ranch lads. This one is distinctly larger for the 46.
Pat Johnston
Skunk Works

Peter Nevai · « **Reply #7 on:** July 28, 2011, 12:21:34 PM »

Quote

The flaps are 3/8" stock, tapered. The airfoil is altered to use this constant 3/8" thick flap. This is a lot easier to manage than building up the flaps.

wwwarbird · « **Reply #8 on:** July 28, 2011, 10:56:36 PM »

Quote from: Mark Scarborough on July 28, 2011, 08:28:11 AM

I think its time for some WW2 fighter /stunt plane combat !

That could be really cool.

Hey Pat, maybe if you do an ME 109 Mark will build one!

Pat Johnston · « **Reply #9 on:** July 29, 2011, 06:30:36 AM »

I think Mark already has a Profile 109 based on my Brodak P-40 wing.
I need to clear up the flap part. The leading edge of the flap is to be a constant thickness of 3/8". It will have the customary tapering as usual.
Pat Johnston
Skunk Works

Glenn (Gravitywell) Reach · « **Reply #10 on:** July 29, 2011, 03:29:11 PM »

Hows about one of these? I may have mentioned it before.

Jim Oliver · « **Reply #11 on:** July 30, 2011, 06:49:35 AM »

Yeah, Pat,

Give us an "H"!! Please??? And use the same airfoil as on the "D".......

Jim

Neville Legg · « **Reply #12 on:** July 30, 2011, 11:05:15 AM »

It isn't a MB 5, the Martin Baker had contra props, that looks like a Mustang of some description??

Cheers

bill bischoff · « **Reply #13 on:** July 30, 2011, 11:42:29 AM »

Hint hint... look at the name of the photo!

Neville Legg · « **Reply #14 on:** July 30, 2011, 01:08:18 PM »

CA stands for Commonwealth Aircraft, its from Australia, first flew in '46 scrapped in '50!

Cheers

Geoff Goodworth · « **Reply #15 on:** July 30, 2011, 05:34:55 PM »

Neville's correct. Having topped 500 mph, I think it was the fastest piston engined fighter and it was powered by a RR Griffon.

Two engines were loaned to Australia for the development and were 'recalled.' The prototype had been damaged and after the engines were returned to the UK, the airframe was sold for scrap. Many Aussie aircraft enthusiasts consider this one of the greates acts of vandalism of Australia's heritage ever.

Given that CA were building P51s under licence, it is hard to imagine that the CA-15 was not in some way inspired by the Mustang but the original design incorporated a radial engine—initially the Cyclone and then the Double Wasp. A front of one airframe was mocked up with a Double Wasp engine loaned by the USAAF but supply became an issue and Wackett went to the Griffon.

One early drawing shows a radial engine and tail feathers of the same style as the Boomerang.

There is a book, Wirraway, Boomerang & CA-15 in Australian Service by Stewart Wilson which tells the story.

David M Johnson · « **Reply #16 on:** July 30, 2011, 08:12:31 PM »

Well you guys probably already know but I'm going to post this anyway. I was looking on the plans and went looking for 1/2 inch foam for the Fuse Core.
Local Hobby store only had 3/8 and for a 3ft x 2ft was 12 bucks. Anyway found 1/2 Polystyrene foam at Home Depot 5ft x 3ft for Garage door insulation, 3bucks and change. Thought I would throw that out there in case anyone else was having that issue.
Thanks for the plans Pat look forward to this plane replacing the Brodak P-40 that I have been using.
David Johnson

Pat Johnston · « **Reply #17 on:** July 31, 2011, 01:47:41 PM »

David and others:
I find the 1/2" foam at Home Depot and Lowes.. Also maybe other good lumber yards may have it. This is the greatest development in Profile construction design lately. Light, strong and twist resistant fuselages add to the overall profile efficiency.
Pat Johnston
Skunk Works

David M Johnson · « **Reply #18 on:** July 31, 2011, 05:03:55 PM »

The foam I found was the white Polystyrene the same stuff they use for the wing cores. It has plastic film on either side but you just have to peal it off.
David

Pat Johnston · « **Reply #19 on:** August 01, 2011, 06:42:59 AM »

Ty, David is right on. They carry what I used to call low density "Beaded Styrofoam". Bottom line is the material used in foam wings. Now I'm confused about all the names of various plastic foam products...
The fuselage technique is, in essence, building a foam wing, or in this case a fuselage. Super trick stuff.
Pat Johnston
Skunk Works

Mark Scarborough · « **Reply #20 on:** August 01, 2011, 08:39:46 AM »

Quote from: wwwarbird on July 28, 2011, 10:56:36 PM

That could be really cool.

Hey Pat, maybe if you do an ME 109 Mark will build one!

Wayne,,
shame on you,, picking on me again!
and for the record as Pat says, yeah there is a profile 109 as well, its hanging next to the built up one that is still *sigh* in primer, though the primer is about half sanded..
and No Wayne,, the profile isnt done yet either

Jim Oliver · « **Reply #21 on:** August 11, 2011, 09:19:21 AM »

The Aussie plane does sound interesting------and I didn't look at the pic very closely at first

;
but, I still want an "H"!

Cheers,
Jim

Michael Boucher · « **Reply #22 on:** August 12, 2011, 07:44:01 AM »

It's a Kangeroo.