XP-82 Twin Mustang/44-83887 Takes Flight Yesterday, 12/31/18

[C VEICH]

Well that would be a real tragedy.

[Chris Brame]

Enjoy it while it lasts...

[SparrowV12]

.478:1 and .480:1 is less than 1/2% difference in RPM. At 3,000 engine RPM one prop is turning 1,434 RPM and the other is turning 1,440 RPM. Not sure that a 6 RPM difference between the two equates to a noticeable variation in thrust. I'm guessing the engine core itself turns the same direction and the nosecase has an idler gear for opposite rotation that affects the gear ratio.

What manifold pressures are these HP figures at and is that with water injection?

This is all a guess on my part though.

The reduction gear ratio's are .478/1 and .479/1 according to my parts book. The -23/-25 are nothing more than glorified -9's with one difference being the inducer wheels in the super charger are substantially more aggressive than the -9 is. The -9 made that horsepower wet (ADI) at 3000/90" MAP. They would've also employed the use of the Simmonds fuel control as I recall.

[bdk]

Thanks for that SparrowV12!

[marine air]

A half a percent of thrust on the Falcon 20-5F and the Falcon 2000 is quite noticeable when hand flying. It makes it feel like the aileron trim needs to be reset or the fuel re-balanced. The North American engineers were no doubt seeking perfection. We have a glass cockpit and everything is digital so it's easier to set the power levers to 1/10th of a percent.

[Snake45]

Big article on the airplane, with lots of great pics, in the new issue of Air Classics, which I got in the mail today.

The gear seemed to be down in all the inflight pics except the one on the cover. Has the airplane flown gear-up yet? Or were the gear 'shopped out of the cover photo?

[JohnTerrell]

In-case it was overlooked earlier, the XP-82 will be displayed and flying at the Space Coast Warbird Airshow in just a few weeks - the weekend of March 15-17.

[OD/NG]

The XP-82 will be coming to Oshkosh this year.

[Ed Likes]

I would like to follow up with the same question someone else posted about the engines on the XP-82. I know the engines are extremely rare. Having said that does anyone know if the XP-82 has any back up engines whatsoever? Or are the 2 engines on the aircraft the only ones known to be in existence?
Also in regards to the XP-82 going to Russia I have it from a source who I consider to be in the know that rumor is just that a rumor no plans of it going there at all. I don't know if the XP-82 is for sale at this time.

[Kyleb]

I would like to follow up with the same question someone else posted about the engines on the XP-82. I know the engines are extremely rare. Having said that does anyone know if the XP-82 has any back up engines whatsoever? Or are the 2 engines on the aircraft the only ones known to be in existence?
Also in regards to the XP-82 going to Russia I have it from a source who I consider to be in the know that rumor is just that a rumor no plans of it going there at all. I don't know if the XP-82 is for sale at this time.

The XP-82's rebuild was financed by investors. The end goal was to find a buyer for the complete airplane and make a profit on the endeavor. As to engine availability, I'm sure there are plenty of right turning Merlins available, but the left turning engine, not so much. Finding one in Mexico was a big enabler for the project.

[JohnTerrell]

Having followed the XP-82 blog, I can only recall the two engines (-23 and -25) being overhauled that are currently in the aircraft. I remember that the left-turning -25 Merlin was a lucky find for the XP-82 project, found in a shed in Mexico City, and I don't recall there being any others found (at least going by the project blog over the years).

At C&P Aviation, which is restoring the F-82E, they're rebuilding, in-house, two sets of left and right turning Allison G6 engines (four engines) for their project, so that there will be a spare for both left and right.

[GRNDP51]

Is overhauling the left-turning Merlin any different? Asking because even though Vintage is the best in the game, could the rarity and very minimal time spent overhauling -25's lead to it being more prone to failure?

[EW439]

If there is a 1/2 percent difference in PROPELLER RPM, that does not equate to 1/2 percent
of THRUST. It just means the propellers are not at the exact same angle of attack. Power is set
by MAP and RPM. So if both engines have the same settings,the POWER output will be the same.
Minus of course the tiny loss from the opposite turning engine having an extra gear in the nose case.
While I agree in theory they will probably have some sort of asymmetrical power,but it would be less than a B-25 with a fresh overhaul on one side and a run-out on the other. Interesting topic.

[mdwflyer]

It is far beyond semantics. The props are synched (by sound), and the manifold pressure is matched, zero rocket science.

[Triplane102]

I would like to follow up with the same question someone else posted about the engines on the XP-82. I know the engines are extremely rare. Having said that does anyone know if the XP-82 has any back up engines whatsoever? Or are the 2 engines on the aircraft the only ones known to be in existence?
Also in regards to the XP-82 going to Russia I have it from a source who I consider to be in the know that rumor is just that a rumor no plans of it going there at all. I don't know if the XP-82 is for sale at this time.

O.K, here it goes fro me, several years ago I got a chance to talk to a "person" who works for a Texas Warbird Collection, & I asked about the XP-82. He said that, yes, the collector wants the XP-82. I HOPE he was/is right about that . I would LOVE to see it stay in the good old U.S.A esp. in Texas !
LET THE PITCHFORKS & TORCHES FLY !!!