GTX AdminRadial Engined derivatives:
What kind of engine was intended for this design?
How about a P-51 with the Allison V-1710 and turbosupercharger from the P-38.
Where would you place the turbocharger?
What if instead of going to the Merlin, they simply added the turbosupercharger from the P-38 to provide the higher altitude performance sought?
It would produce a higher critical altitude, though depending on where the turbocharger was placed, it could lead either to excess bulk or a reduction in fuel capacity.
The British did actually analyze the idea of developing a RR Merlin with an integral turbocharger (which eliminates volume constraints), but they ultimately decided (if I recall), that the supercharger would be better
- The turbocharger would use a twin-staged arrangement with an intercooler: This variant would produce a higher critical altitude, probably a more linear increase in the turbochargers RPM with altitude, and only small losses of horsepower to drive the charger due to backpressure; regardless, thrust falls off at higher altitudes due to the speed of sound dropping at higher altitudes and the rotational velocity of the blades producing a loss of efficiency across the tips.
- The supercharger version as developed would be twin-staged, twin-speed, with an intercooler, aftercooler, and casing cooling as well: Though the supercharger would have a less linear increase in performance compared to a turbocharger, one could easily clutch to high speed at the critical altitude for the lower-speed setting and depending on the throttle position you'd maintain full pressure as you go; while some horsepower would be lost to drive the supercharger, the extra cooling would add more horsepower that the turbocharger design did not have, and no back-pressure would be present. All of these would come close to, or possibly offset the losses.
- Since superchargers do not tap off exhaust gases, those end up shooting out the pipes: With the pipes shaped properly, this can produce a thrusting effect; with manifold pressure kept at the max right on up into the high 20,000 foot range, the thrust increases as the air-pressure outside gets lower. Since the propellers are losing thrust at higher speed, this would recover some back.
If I recall, they ultimately felt the extra-cooling, and thrusting effect would offset the effects of the turbocharger with the exception of lower speeds at higher altitudes.
kitnut617I really like the Mustang FTB derivatives
elmayerleFrankly, a redesigned Allison with a two-stage supercharger similar to the Merlin's would be a simpler solution and allows some interesting alternatives.
Turns out they proposed exactly such a thing: I don't know why the USAAC rejected it
raafifthe Corstang ....
http://www.aircraftresourcecenter.com/Gal8/7001-7100/gal7073-Corstang-Miller/00.shtm
That is just genius, I've contacted the guy who created it: I'm asking some questions as I'd love to get a line-drawing of that made some-day.
TopheAfter the F-52, the F-52F turned back to single engine, like a "normal" Mustang...
Thanks Raafif
It's unorthodox, but it's absolutely fantastic.
Jeffry FontaineFound this at the Fine Scale Modeler forums (click on image or html to view article):
F-82R (R for racer) Twin Mustang built by Howard Markel
(Image source: Howard Markel via Fine Scale Modeler)
Looks like it'd be fun to race around, and considering the design has no second canopy, I could imagine that it not only could fly faster; one could stuff a lot of fuel in there...
BTW: This is a batch reply
(I haven't been on this site very often, and saw some very interesting ideas and responded to them, as well as provided what I assume to be constructive critique)
