It's a bed for a fish or something like that.

Description

The MiG-21Bis was the ultimate development of the MiG-21, fitted with the Tumanskiy R25-300 turbojet engine and a great number of other advances over previous types. The aircraft were developed into two variants, the Izdeliye 75A and 75B, with the difference being their avionics, the 75A was made for the export market whilst the 75B was made for the Soviet Air Force, with both having the designation Fishbed-L and Fishbed-N respectively.

Iraq received 61 MiG-21Bis (izdeliye 75A), delivered from 1983, these aircrafts would partake in the Gulf War as interceptors and fighter cover, four of these were shot down during the war, two by F-18s and another two by F-15s, some fled to Iran and the rest were destroyed either during the Gulf War or during the 2003 Iraq War

In this SimplePlanes version, I have to admit I actually gave the airplane the wrong designation, it should've been Fishbed-L not Fishbed-N, but anyways, the aircraft is armed with two R-3Rs and four R-60MKs, it had a detailed cockpit, roundels, and camouflage, it carried a fuel tank that can be detached.

Credits to striderxxl for HUD and radar display

Controls

VTOL : flaps
Trim : trim
Throttle 100% : afterburner
AG2 : drop fuel pod
AG3 : jettison weapons
AG4 : drogue chute
AG5 : open canopy
AG6 : landing lights
AG7 : lights

Other version

Simplifed version