It could be a fuel tank or a storage for carrying atgms.
Or maybe a ECM/Radar pod?
It seems the box can open itself. Maybe it is used for carrying mines or bombs.
Cargo pod or maybe measuring equipment
I’ll go with some kind of sensor, either a radar or EW surveillance/jammer. With just a cargo box being a close second.
It’s not related to this pod, but this can be seen on the Mi-28NM if you have it in your line up and you have another aircraft selected
It’s a radar pod used to guide khrizantema.
This shit will haunt me, 3h of searching and nothing… I would write to Mil Helicopters if I wasn’t too tired
Seen a couple of discussions about it on other sites - no one seems to know - suggestions of ECM pod, storage space for tools, or flight monitoring equipment.
something that hasn’t been suggested but is equally plausible - a counter weight for the full load out on the other side!! Why you would fully load one side and not split it I have no idea…
The helo is the prototype Mi-28N #014 (converted from Mi-28 #012). The only pics with this pod seem to be this one helo during its time at the test centre at Ramenskoye airfield.
Although similar in shape the pod isn’t the VSM-1 mining system is wrong in detail and it lacks the very prominent tubes visible poking out the bottom.
As its the prototype, at a test airfield, and the pod doesn’t seem to match any recognised systems I would say it’s most likely proprietary test equipment.
I did some more research and I think it was full of electronics for testing, like you said. 014 was also called OP-1.
Is there a way to visually estimate its volume?
It’s a cope box