This January, russian defense ministry's official media Krasnaya Zvezda has claimed that their Su-34 tactical bombers were already using Kh-47M2 Kinzhal air-launched ballistic missiles for strikes on Ukraine. Later this information was denied by the russians themselves.
This time, there's a new narrative shared in the russian media: that their allegedly hypersonic missile can be fired from the Su-57 aircraft — the self-proclaimed 5th (in fact 4++) generation fighter. The press is citing the opinion of Vladimir Popov, an airman and retired major general, who allegedly "settled this question."
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In short, his verdict on this matter is that russian Su-57s can use Kinzhal missiles but it "will have to sacrifice stealth" for this.
The statement is followed by Popov's speculations, he believes that the russia "does not equip Su-57 with a container or bomb bay for the Kinzhal system" precisely because in that case, the fighter would glow on enemy radar displays in the same way a Su-34 or a Su-35 does. This, he says, would be "impractical for a fifth-generation aircraft." The retired airman also assumes that tests could be underway of a Kinzhal "made specifically for the [Su-57] fighter."
Defense Express finds these arguments untrustworthy for the following reasons. Firstly, the range of the Kinzhal aeroballistic missile is anyway more than enough to launch Kinzhals from a standoff range, beyond the reach of Ukraine's air defense systems. Therefore, preserving stealth should be of little worth in relevant realities.

Secondly, the mention of Su-57's visibility to radars is also surprising. After all, in the case of MiG-31K aircraft, the constant tracking of Kinzhal carrier takeoffs and missile launches by war monitoring channels has never made russians have second thoughts about using MiGs.
Earlier, Defense Express covered why the russian project on adapting Kinzhal missiles for the Tu-22M3 strategic bomber failed.
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