SU1946 stands for Simple Universe 1946, it is a series of late-WWII (or prototypes) planes plus some fiction. Planes in this series would have significantly better performance than their historical counterpart, and would receive a "Z" in their names to distinguish them from other, more accurate replicas.

History:
Kostikov 302, in real world, was a Soviet prototype interceptor that comes in two configurations, a rocket powered version (302P) and a rocket + ramjet version (302).

In our Simple Universe story, after the end of the Second Simple Universe War, the Soviets began to lose ground in making better fighters than the West, and they had to find ideas in some less normal places. They recruited the Germans and absorbed some of the late-war Junkers design, and they had to restart the project they gave up back in 1944, the Kostikov Project 302.

The 302 uses ramjet engines to provide most of the power, but ramjets require reaching a certain speed to start up, so it would have to use a conventional liquid-fuel rocket motor to reach the speed before igniting the ramjets.

In real world, ramjets for subsonic operation have different design with those for supersonic operations (supersonic ramjets require a cone to slow the airflow to subsonic). However, since there's no supersonic mechanism in the Simple Universe, this became a non-issue.

The 302 boasts good agility, but the complexity in operation limits its use.

Features:

• Ramjet engines (start at 0.8 mach, 614mph/990 km/h)
• Working ramjet thrust meter (important because the ramjet throttle only has on/off)
• Custom gun sight
• Nav lights and antenna wire

Performance:
Speed: 1790 km/h at sea level (ramjet only)
Agility: 6.78 seconds to turn 360 deg at sea level @1530 km/h (ramjet only)

Activation Groups:
AG1: Airbrake (red light on the left engine gauge)
AG7:Nav Lights
AG8: Ramjet master switch (Green light on the right engine gauge)

It's a bit difficult to land without spinning, but after some practice you should be able to correct it before it spins out of control.