With the recent announcement of germany transfering gepard to ukraine.
Can a helicopter engage something like a gepard with unguided rocket with any real chance of success or it's just gonna get shot down?
Unlikely. To use rockets one has to be flying towards the target. Aerial rockets generally have a maximum range of 2.5km-3 km (although theoretical ballistic ranges are sometimes higher). The Gepard has a maximum range of 4km.
Helicopters would be engaging with missiles though - with Vikhr giving about 8km range and Ataka closer to 6km they can easily outrange the Gepard. However, to do so they have to see the Gepard first. If the safe window is only 2km-4km wide (and more than 4km away from the SPAAG to begin with) the probability increases that the helicopter won't spot the Gepard until it is already within range of the Gepard.
So this system is quite dangerous to helicopters, even if the Mi-28, Ka-52, and some versions of the Mi-24 can theoretically attack it with guided missiles from ranges at which they are immune.
