WesWorld

Polikarpov I-31 all-metal monoplane fighter with enclosed cockpit and retractable landing gear
Wingspan - 9.15m; Length - 7.9m; Height - 3.0m; Wing Area - 16.7m2
Crew - 1; Engines - x 700HP Klimov radial engine; Empty weight - 1,425kg; Maximum weight - 1,815kg
Defensive armament - 4x 7.62mm ShTAS machineguns
Top speed - 255kts; Maximum altitude - 8,500m;
Maximum range - 1,000nm
Combat radius - 350nm

Figures courtesy of Planebuilder

Capabilities of obsolescent biplane fighters:

I-3
Crew - 1
Speed - 135 kts
Range - 110nm
Ceiling - 7,200m
Armament - 2x 7.62mm MG
Strike version I-3S can carry a 100kg bombload 70nm

I-6
crew - 1
Speed - 140kts
Range - 130nm
Ceiling - 7,500m
Armament - 2x 7.62mm MG
Strike version I-6S can carry a 100kg bombload 90nm

Why not simply use the I-16 which is essentially the same?

With regards to planebuilder and the range figures. Thats essentially the absolute maximum range. Normally you're limited by the volume of the fuel tanks. Planebuilder goes by weight instead.

I don't see that that is a problem with a fighter: it makes sense for MTOW to consist of structure, full ammunition and full fuel tanks.

I don't think there have been that many occasions when a fighter has needed half a ton of sandbags...

Quoted

Why not simply use the I-16 which is essentially the same?

Yes, its the I-16's airframe. However, the Russian Federation has access to more powerful engines than OTL USSR did. The first I-16 started out with, IIRC, a 480hp radial.

Its not common to actually take off at mtow, tending to need longer unways then and generally more difficult to handle.

Speed is pretty high compared to the historical, but normal for WW i think. What supercharger pressure have you used, probably around 1.2-1.5bar at this period.

Polikarpov I-34 all-metal monoplane fighter with enclosed cockpit and retractable landing gear
Wingspan - 9.15m; Length - 7.9m; Height - 3.0m; Wing Area - 16.7m2
Crew - 1; Engines - x 1,000HP Klimov radial engine; Empty weight - 1,500kg; Maximum weight - 2,000kg
Defensive armament - 4x 7.62mm ShTAS machineguns
Top speed - 314kts; Maximum altitude - 13,000m;
Maximum range - 1,000nm
Combat radius - 350nm

Lavochkin IK-34 all-metal carrier-based monoplane fighter with enclosed cockpit and retractable landing gear
Wingspan - 10.0; Length - 9.0m; Height - 2.5m; Wing Area - 18.5m2
Crew - 1; Engines - x 1,000HP Miliukov in-line engine; Empty weight - 1,855kg; Maximum weight - 2,600kg
Defensive armament - 2x 7.62mm ShTAS machineguns, 1x 20mm ShVAK cannon
Top speed - 310kts; Maximum altitude - 13,000m;
Maximum range - 1,000nm
Combat radius - 350nm

Range vs weight seems awfully high for a single-engined plane of this period and speed. The historical I-16 had a range of less than 450 nm, on a similar weight. WW's better engines will raise the top speed, but the range won't change by much. Ranges of the sort listed are, for the period, more the province of the twin-engined fighters that were popular.

The I-34 seems to be an I-16 with an uprated engine, presumably a two-row radial given the power. I'm sure the change in the CoG would make it even more lethal than it was historically. Range is rather massive without drop tanks.

The IK-34 seems to be similar to the LaGG-1 but with massively less weight somehow. You'd think a carrier version would be heavier...

For both aircraft the maximum altitude is massive for the period. Could you tell me what figures in planbuilder you used for 1. supercharger altitude 2. failure g and 3. maximum design airspeed please?

Wouldn't have to be a two-row radial, the BMW-132N was pushing 1000 hp, and later models exceeded 1000 hp, with only 9 cylinders in 1 row.

Supercharger altitude-15000ft
Indicated airspeed - 350kts
Failure Gs-9

What efficiency are you using for the Klimov and the Miliukov engines? I'd be worried about a not-to-exceed speed of 350 kts IAS when the plane's top speed is 314 or 310 kts, either way you'd be in danger of reaching it in a dive, I'd think.

Typical efficiency for the time [for performance engines] is between 250g/hp-hr and 300g/hp-hr which comes out at between 14% and 20% efficient IIRC.

For the max permissible airspeed you can modify the planebuilder sheet by putting a formula into the square on the airframe page. = [factor] * [IAS airspeed on the maximum speed page]. The factor depends on how safe you want your aircraft to be. Italy used a factor of 1.5x so that is what I'm using. You might want to go for 1.33x instead and accept the dive limits. Of course you might be limited to lower speeds in practice because of the critical mach of the wings (0.69M for the P-38 which is about 450mph at alt, caused a lot of crashes)

I'll work on revisions.

Lavochkin IK-34 all-metal carrier-based monoplane fighter with enclosed cockpit and retractable landing gear
Wingspan - 12.2; Length - 9.15m; Height - 2.5m; Wing Area - 22.3m2
Crew - 1; Engines - x 1,000HP Mikulov in-line engine; Empty weight - 1,650kg; Maximum weight - 2,031kg
Defensive armament - 2x 7.62mm ShTAS machineguns, 1x 20mm ShVAK cannon
Top speed - 312kts; Maximum altitude - 13,000m;
Maximum range - 800nm
Combat radius - 270nm

Empty and maximum weights are reversed.

Essentially, an early in-line version of a Zero?

Looking at the data for the Zero, it is quite close.

But without the Zero's long range.

Teh Zero WAS a few years later, which will help with the range. But for the mid-30s, a range of 800 miles on a single engine fighter is VERY good.

of the Pe-2

First flight in 1936

Pe-2 twin engine Fighter
Wingspan - 18m; Length - 12.65m; Height - 3.5m; Wing Area - 46.5m2
Crew - 1; Engines - 2x 1250HP Klimov in-line engines; Empty weight - 5,280kg; Maximum weight - 7,260kg
Armament - 2x 14mm machineguns and 2x 20mm cannon in the nose
Top speed - 342kts; Maximum altitude - 12,500m; Maximum range with no bombload - 2,100nm at 293 kts
Combat radius - 800nm at 293 kts



Recce version is similar to the fighter, with the following changes:
Deletion of both 20mm cannon
1 additional crew member
Increased pressurized volume

Pe-2 twin engine high-altitude recce aircraft
Wingspan - 18m; Length - 12.65m; Height - 3.5m; Wing Area - 46.5m2
Crew - 2; Engines - 2x 1200HP Klimov in-line engines; Empty weight - 4,775kg; Maximum weight - 7,260kg
Armament - 2x 14mm machineguns in the nose
Top speed - 342kts; Maximum altitude - 14,000m; Maximum range with 200kg payload - 2,350nm at 293 kts
Combat radius - 900nm at 315 kts




Petlyakov Pe-2
Year of First Flight: 1936

Description
Carrier or Rough Field
Monoplane with Struts
Conventional Fuselage Interceptor/long-range escort Characteristics: Weight (maximum) 16,000 lbs Weight (empty) 11,046 lbs Length 41.5 ft Wingspan 60 ft Wing Area 500 sq ft Sweep 10 degrees Engines 2 Klimov 1200 Piston 1263 hp
at 17,000 ft Crew 1 Typical cost $0.087 million in 1939
Total number procured 2000
Performance: Top Speed 343 kts =393 mph at 17,000 ft Operational Ceiling 41,000 ft Range 2,350 nm = 2,706 miles with 372 lbs payload 435 lbs released at halfway point Climb 2,441 fpm Cruise 293 kts = 337 mph at 33,000 ft Corner Speed 210 KIAS = 313 kts at 25,000 ft

Turning Rate 18.3 deg/sec Radius 3,320 ft
Internal Data: Intake / Fan Diameter 10 ft Bypass Ratio 91 Engine Weight 1518 lbs
Overall Efficiency 22.5 percent

Structural Factor 1.00
Number of Wings 1.01
Number of Fuselages 1
Limiting Airspeed 500 kts
Wing Ultimate g Load 8.00 g
Wing Taper 0.3
Wing Thickness at Root 1 ft
Tail / Canard Factor 0.4
Number of Nacelles 2
Length 6 ft
Diameter 2.8 ft
Fullness 0.2
Fuselage Diameter 3.8 ft
Fuselage Fullness 0.2
Pressurized Volume 20 percent
Cargo Decks 0
Cleanness 78 percent
Unstreamlined section 3 sq ft
User equipment 650 lbs

Edited to back down some stats

Got a Planebuilder for this? It seems awfully fast and long-ranged.

The historical Pe-2I (a fast interceptor version of the Pe-2), which was equipped with a pair of 1650 hp VK-107A engines and flew in 1944, only had a top speed of 408 mph, with a range of around 750 miles.

Quoted

Originally posted by AdmKuznetsov

Description
Carrier or Rough Field
Monoplane with Struts

Fuselage Fullness 0
Cleanness 80 percent

How does a plane with external bracing have top notch streamlining? And also, the fullness is at the absolute minimum indicating a teardrop shape. Should it not be up around .3+ ?

Also, the Klimov was based off the Hispano Suiza 12Y, which would not fit in a 2 ft. diameter nacelle. None of the various engines I've dug up diameters for would.