Hello Jean-Philippe.

I'm pretty sure at all MiG-21 bis aircrafts had the SPS installed. A more interesting question would be "Did all MiG-21 PFMs have the SPS installed ?". To my knowledge, the first batch (MiG-21 PFM type 77 with a single-piece canopy) didn't, the later batches (MiG-21 PFM type 94 with a fixed windscreen) did. Could someone please confirm this statement or not ? Thanks.

The "French modellers"