Briefly, from a "classical" military science point of view, here are a few related definitions and theorems.
1- BTR (APC): BTR's main role is to provide for the infantry support of tanks. Amphibious capability is a must.
2- BMP (IFV): BMP's main role is to provide for the infantry support of tanks. Amphibious capability is a must.
3- Medium/heavy tank (MBT): Requires supporting infantry.
4- TBTR ("main battle APC", MBAPC): BTR with an armor which is in the same class as a medium/heavy tank.
5- TBMP ("main battle IFV", MBIFV): BMP with an armor which is in the same class as a medium/heavy tank. MBBMP can replace both the MBT and the IFV; this form of deployment would not be optimal though.
6- Mi-28, Ka-50, and Ka-52: Aerial main battle tank (AMBT)
7- Ka-50: Aerial main battle tank (AMBT) enabled through artificial intelligence (AI)
8- Mi-24, Mi-40, Mi-42, Ka-??: Aerial main battle IFV (AMBIFV). By analogy, AMBIFV's main role is to provide for the aerial infantry support of AMBTs. In reality, AMBIFVs can be utilized independently of AMBTs; this form of deployment may not be optimal though.
9- If we assume an AMBT is 6 times as fast as an MBT, just due to this factor, each AMBT can replace at least 6^2 = 36 MBTs (plus all the huge amount of the water obstacle assets crossing, the air defense assets that would become redundant, and ...). By the way the only time I have seen this power-of-two relationship being put in writing outside Russia was when Mindstorm wrote about it here.
10- By analogy with the MBTs, AMBTs require supporting aerial infantry. In reality, AMBTs can be utilized independently of aerial infantry.
Last edited by Morpheus Eberhardt on Thu Aug 14, 2014 4:33 am; edited 1 time in total