home made spit

[visaliaaviation]

Saw a very interesting aircraft this a.m. Robert Danforth's (??) Allison powered Jurca Spitfire spent last nite and this morning at Visalia.. he was passing thru from Washington , on his way to Rialto, CA. I'd seen a video of this project but being full size, is quite impressive, up c;ose and personal. Gets my juices going for a full size Mustang!

[Bill Greenwood]

I think his name may be Defore or Deford. I'd enjoy talking to him and seeing the plane. I have been told the Jurca projects are no snap to build, of course the important thing is how it flies and looks. Many of the scale repicas lack enough wing area, or power, and some have had cooling problems.

[visaliaaviation]

Bill,
I saw a Jurca wood wing once. It looked way overbuilt to me. compared to photos of Hugh's h-1 wing it certainly seems so. I'd heard that none of Jurca designs were ever truly engineered, just eyeballed!

You might be right about the fellow's name. I do recall he said it weighed 5,828 lbs. empty. How does that compare to a real Mk XI?

[bdk]

His last name is DeFord. The Jurca designs had very thorough stress analysis and testing performed at one of the local French universities.

http://www.eaa.org/homebuilders/list/Sp ... DeFord.asp
http://www.spitfirebuilder.4t.com/custom4.html
http://www.marcel-jurca.com/index.php?o ... &Itemid=54

We have stress calculations of the MJ 100 made by ESTACA engineer school in France.
These documents are available for consultation.
No copy will be sent to private persons .
These documents are parts of Marcel Jurca "know how".
In case of official demand , these documents will be sent to civil authorities.

Last edited by bdk on Thu Aug 23, 2007 3:22 pm, edited 1 time in total.

[Vital Spark]

http://www.eaa.org/homebuilders/list/Spitfire%20MK%20IX_DeFord.asp

[Bill Greenwood]

I wrote "lack enough wing AREA", I wasn't referring to strength, however I doubt if any of these replicas are as strong as a Spit which is built for 9g positive and 8g negative(ouch!) . Some make the fuselage for example, maybe 3/4 size, but the wing is only 5/8 scale so there is less wing AREA. The result is a higher stall and landing speed. The Thunder Mustang for example, has a higher landing speed than a MKV Spit! I wonder why he used an Allison instead of a Merlin, especially one of the earlier lighter Merlins with the single stage supercharger. Maybe that Allison has no supercharger and is lighter?

Last edited by Bill Greenwood on Thu Aug 23, 2007 3:37 pm, edited 1 time in total.

[bdk]

I believe the Allison is stock (with the supercharger). I guess he wanted an engine that required a minumum of maintenance/maximum fun quotient. It also has a Ham-Std prop.

[Matt Gunsch]

Bob's Spitfire is full size, he has some Spitfire parts in it, the landing gear and I think the seat. The fuselage is steel tubing, and the wing is wood. I have seen it up close and he did a very good job on it.

[Bill Greenwood]

The ad for the Jurca plans gives the design strength as plus 6gs and minus 4gs, certainly enough for any normal spirited sport flying using reasonable care, that is don't try a 5 g rolling pullout. It give power options as 240 hp to 1500, quite a wide range. It doesn't give any weight specs.

[Chris]

Bob used the Allison because he was able to get it at a VERY good price and it was in great shape even before overhaul. Plus the SAE tool factor. You really have to get up close before you can tell it's not a "real" Spit. He did a great job on this plane and is a terrific person to boot.

[Hal B]

Bob Deford cleared customs at BLI last week. That is one nice "homebuilt", even sounds like the real thing. Sorry I didn't get to talk to him about it.

[snj-5]

Met Mr. DeFord at the McMinnville, Oregon (NWAAC / Northwest Antique Airplane Club) fly-in last weekend. It's a very convincing replica, and looks very much like the real thing. The prop is off of a DC-3. A friend of ours (Vern Goodsell) did a good amount of the fabrication/building of the fuselage (I think I heard someone say someone else built the wing...???). Bob flew it on Saturday during the fly-in, and it sure sounded and looked sweet in the air.... I think I heard Vern say the wind screen and canopy are original Spitfire parts, as are some of the cockpit parts (like someone else said, the seat, stuff like that).

Here are a few pics from the NWAAC fly-in

http://www.havasreti.com/images/McMinnv ... tfire1.jpg
http://www.havasreti.com/images/McMinnv ... tfire2.jpg
http://www.havasreti.com/images/McMinnv ... tfire3.jpg

Bela P. Havasreti

[Curtis Block]

I saw it at Arlington this year. Absolutely beautiful machine.

[visaliaaviation]

I have a bit more time today, so offer a few more comments/obsevations.

The aircraft is striking and well built. Workmanship is outstanding.

There are some major shape issues, so its evident that Jurca did not access any real spit data (most of his designs seem to miss the mark. Spit affeciandos will be disapointed, but it is emminently recognizable and does draw a crowd.

IMHO- the aircraft does combine a number of known WWII era technologies into one airframe, evenif its not a perfect representation of a Spit. It certainly seems to fly like a WWII era aircraft.

thanks to those that offered corrections and data.

[wendovertom]

Maybee this is notthe right place, but, wondering about the scale replicas of P-38s we have seen from time to time here - also, would they fit under the "sport pilot" catagory of planes?

Tom P.