Minimum fighters mayhem

...
WI Messerschmitt had installed the motorkanon and propeller ABOVE the crankshaft?
How far would the thrust line be above the original?
How much would that shorten MLG legs?
How much would that reduce landing accidents?

If anyone will install the prop above the crankshaft on the DB 601/605 engines, that would've been the Daimler Benz. Had that happened, we'd have Bf 109s without front vision to speak about.
Shortening landing gears on Bf 109s means that they wheels also more closely together now, that will play havoc with ground handling, especially - it was the non-vertical stance of wheels that was to blame for the tricky ground handling of the 109s, as well as non-vertical stance of the U/C legs

That XP-77 profile explains the unique canopy shape. Rumour has it that Bell’s XP-77 suffered poor airflow over its tail feathers because the canopy’s rear half was sloped too steeply.
WI Bell installed a more gently-sloped aft canopy?
How much would that improve airflow over the tail?

I don't know about all of that.
What I know was that V-770 was a lousy engine before 1945-something, while even post-war was not regarded well. The British, German, Czech or Italian air-cooled Vee engines were far, far better.

Perhaps I was not clear enough in explaining when I suggested ROTATING a single-row, Wright/Continental R-1820, radial engine 30 degrees about its crankshaft. The crankshaft would still be pointed straight ahead, but rotation would center a gap - between cylinders - top dead center.
Then an offset PSRU raises the thrust line (er propeller hub) above the crankcase, allowing installation of a Motorkanon through the - raised - propeller hub.
The PSRU would still be bolted to the crankcase, though there might be an extra - engine mount strut - running straight back to the firewall.

That would've been off-set reduction gear. It was done, eg. on the Pobjoj Niagara engines, that were making 10% power the Cyclone 9 did. For the prop gun installation, it would've needed rotating engine so the cannon barrel clears the top cylinder. Obviously, Wright will need to make the reduction gear in such a fashion 1st. It will also mean that USA is actually manufacturing cannons for aircraft in said 1938 year. Perhaps too many techological novelties for an emergency fighter?

We might install a cooling fan, but it would be behind the engine, pulling air towards cowling flaps. Cowling flaps would only be on the sides of the fuselage - like FW109 or Sea Fury.

I like the idea of cooling fan. Quirk being that it is an another thing engine manufacturer needs to design and produce - all well for a fighter that will enter service in 4-5 years, but for an emergency fighter?
 
This is late Just Leo's take on minimum fighters - alternative versions of the XP-77, Ambrosini 207, Caudron 714 and Irbitis I-16. Obvious things are that Bell is now used by the USN, Caudron got a V12 engine, while I-16 got the retractable U/C.

091014-335-png.368685
 
Bell F2L needs a taller turtleneck to smooth airflow over the tail feathers.

Caudron C.417bis needs a much larger wing to improve climb rate.
 
Over on www.secretprojects.co.uk there is a thread on a North American Aviation light weight fighter proposal designed by Edgar Schmued and variously referred to as NAA P-500 or Shop Charge SC-46. It looked like a cross between a P-51H and a Bell XP-77, powered by an air-cooled, inverted Ranger V770 engine.

Speaking of the Bell XP-77, the thread includes a cutaway drawing of a proposal to fit the XP-77 with a sliding bubble canopy, intercooler, turbo type 4 and a jet exhaust. It would be armed with .50 HMGs.

There are also a few pictures of Edo’s XOSE-1 prototype floatplane - also powered by a Ranger V770 - that competed with the Curtiss Seamew.
 
Last edited:
Much thought was put into the Madsen 23mm for US designs before 1940

It was, however neither that cannon was in production in the USA. IMO, both UK and USA made a mistake by not purchasing license for Oerlikon cannons already by mid-1930s.

Bell F2L needs a taller turtleneck to smooth airflow over the tail feathers.

Caudron C.417bis needs a much larger wing to improve climb rate.

Well, those are Just Leo's drawings, he is not anymore with us, unfortunately.

Size of the wing is a trade-off. It mostly depends on weight of complete aircraft, so the wing loading is within desirable range - eg. wing loading of the C.714 was lower than of the Bf 109E. What the C.714 lacked was power, the Renault engine making just 450-500 HP, or less than half of what DB 601A or Merlin III were making. Even the latest HS 12Y engines were almost twice as powerful. In order to improve power to weight ratio (= that will help both for high speed and climb), French went with a prototype that was powered by I-F Delta 12, another 12 cyl air-cooled engine (probably J-L had that one in mind?). A 50% increase of power improved both speed and RoC, while another prototype was supposedly even faster:
link

Over on www.secretprojects.co.uk there is a thread on a North American Aviation light weight fighter proposal designed by Edgar Schmued and variously referred to as NAA P-500 or Shop Charge SC-46. It looked like a cross between a P-51H and a Bell XP-77, powered by an air-cooled, inverted V770 engine.

Speaking of the Bell XP-77, the thread includes a cutaway drawing of a proposal to fit the XP-77 with a sliding bubble canopy and a jet engine powered by engine exhaust.

There are also a few pictures of Edo’s prototype for hat competed with the Curtiss Seamew.

The earlier the V-770 is cancelled, the better ;)
I'm not sure that M4 37mm cannon was a good idea, too (the XP-77 being the smallest A/C that was set to carry it). If someone in the USA wants a light fighter ASAP in the late 1930s, people can design a fighter around the Wright Whirlwind or the P&W TWjr: both are in series production, there is plenty of mechanics that know the engine well, engines were noted as reliable, they were lightweight, short and of small frontal area - what's not to like? Later versions of the TWjr were making 825 HP, granted not at altitude, but still.
Bell proposed a turbocharger-outfitted improved XP-77, not jet ('jet exhaust' is not a 'jet engine'): link
 
......
I'm not sure that M4 37mm cannon was a good idea, too (the XP-77 being the smallest A/C that was set to carry it).
———————————————————————————-

Are you sure?
Most sources say that Bell XP-77 would be armed with a 20mm motorkanon and various Browning .50 cal. MGs.
I doubt if any light fighter could lift a 37mm cannon.
————————————————————————-

If someone in the USA wants a light fighter ASAP in the late 1930s, people can design a fighter around the Wright Whirlwind or the P&W TW......... link[/QUOTE]
———————————————————
Which is why I suggested a (fictitious) Gregor Monoplane with a 20mm motorkanon firing between the upper cylinders of an R-1820 single-row radial engine.
OTL a few years later, the US Navy adopted the - popular - Vought Kingfisher armed with a pair of .30 caliber Brownings. One Browning fires between engine cylinders (R-985 radial) and the breach was in the lower right corner of the pilot’s cockpit. The rear observer fired the second Browning from a flexible mount.
 
Are you sure?
Most sources say that Bell XP-77 would be armed with a 20mm motorkanon and various Browning .50 cal. MGs.
I doubt if any light fighter could lift a 37mm cannon.

Indeed you're right, the 20mm was proposed.

Which is why I suggested a (fictitious) Gregor Monoplane with a 20mm motorkanon firing between the upper cylinders of an R-1820 single-row radial engine.
OTL a few years later, the US Navy adopted the - popular - Vought Kingfisher armed with a pair of .30 caliber Brownings. One Browning fires between engine cylinders (R-985 radial) and the breach was in the lower right corner of the pilot’s cockpit. The rear observer fired the second Browning from a flexible mount.

What kind of cannon you are planing for that one? How much the Gregor monoplane can loose (drag, visibility reduction) due to installing a 55 in Cyclone 9 engine instead of 44.13 in TWjr?
Having synchronised MGs firing through the prop arc is nothing new, even if the MG fires between the cylinders.
 
................... What kind of cannon you are planing for that one? How much the Gregor monoplane can loose (drag, visibility reduction) due to installing a 55 in Cyclone 9 engine instead of 44.13 in TWjr?
........ [/QUOTE]
———————————————————————————-

ATL Gregor Monoplanes’ outer mold lines, pilot visibility, etc. would be similar to other 1938-vintage, radial-engined fighters (Curtiss P-36, Grumman Wildcat, Seversky, etc.) because none of the new gear would project above the cowling. A GM pilot would barely see the top edge of the prop spinner because upper mold lines run straight forward /horizontal from the base of the windshield until the intake lip curves inward/downward.
As seen from a distance the only visible difference would be the upward-displaced prop spinner. From a distance, GM cowlings resemble Avro Lincoln, Avro Shackelton or NAA F-86D intakes. Intake area would be roughly the same size as other airplanes powered by Wright/Continental R1820 radial engines.
Yes, the R1820’s larger diameter would increase drag slightly more than a Twin Wasp.
Improved internal airflow would reduce drag a little

Only when you got close, would you see the 20mm motorkanon’s muzzle protruding from centre of the spinner.
Trials included Bofors, Oerliken, Hispano-Schwuiza, Polsten and Madsen 20mm autokanons. At press-time, engineers were still narrowing down armament options.

I keep repeating ‘single-row radial engine’ because it took Gregor and Wright many months to figure out how to install a motorkanon in a single-row engine. When asked about installing a motorkanon in a twin-row radial engine, they mumble, scratch their heads and wander off looking confused.
 
Last edited:
Top