(Since i did use AI to colourise it... I'm posting the original just in case the shape was altered)
Mig-3U (I-231)
Empty Weight: 2583kg
Loaded Weight: 3287kg
Wing Area: 18.00m2
Engine: AM-39 (Credit to CORSNING for power output)
Grok Estimated Sustained Turn Time at SL-1000m, no flaps
20-21 sec (Military Power)
19-20 sec (WEP)
(BF-109G's are comparable in turn)
Armament:
2x 20mm ShVAK (150 rounds per gun)
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Here are the juicy AM-39 engine powercurves
Differences compared to standard Mig-3
Airframe
- Fuselage lengthened to 8.62 m (MiG-3 8.26 m); cockpit moved aft and raised.
- Fuselage all-wood monocoque (no welded steel centre truss).
- Canopy wider and higher; better view.
- Fin/rudder reshaped; I-231 stabilizer dropped 200 mm (back toward MiG-3 height) to kill tail shake seen on I-230.
- Main gear redesigned: new doors, smaller wheels 600×180.
- Tailwheel mechanism changed; tailplane raised 200 mm on I-230 to clear it.
- Empty weight down: MiG-3 ~2,700 kg → I-231 2,583 kg.
- Same span/area on the standard article: 10.20 m / 17.44 m² (D-02 only had a longer wing).
- Outer-panel spars metal, not wood.
- Centre spar no longer cut by the old ventral radiator tunnel.
- Radiator inside the fuselage under the cockpit (P-310); main intakes in the wing roots, plus two small ventral inlets.
- Oil cooler in a ventral tunnel between the wells.
- I-231: larger radiator (~30 m²) plus an intercooler loop for the AM-39 supercharger.
- New Engine: AM-39 (From 1350hp on AM-35 —> 1800hp on AM-39)
- Improved from machine guns on standard Mig-3 to 2x 20mm cannons on the Mig-3U (I-231)
