According to this link, these Su-34NVOs have got Su-35s 117S engines on them. Maybe new electronics as well. Interesting:[Su-34] The NAZ factory in Novosibirsk (UAC(ROSTEC)) has given the VKS a batch of Su-34s, reference not visible. Type not specified, NVO? At least 2 aircraft, judging by the photos. A (white) fuel tank can be seen under the belly.
Russia received deeply upgraded Su-34Ms powered by Su-35's engine
Russia received deeply upgraded Su-34M powered by Su-35's. This will bring more thrust than the current one. Rostec announced the delivery as the first for 2023
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