In 1970s the antonov AN-22was adopted as a test bed for air launched ballistic missiles
was this something that was realistic and operationally possible
any potential advantages over SLBM ALCM and silo based ICBM
thanks
I presume you are thinking in terms of intercontinental range ALBM's carried by transport style air craft as opposed to shorter ranged weapons carried by bombers ?
As I understand it, on paper at least a force of intercontinental range ALBM's with a portion on permanent air borne alert (or perhaps more plausibly having the ability to keep a portion on air borne alert during a crisis and or perhaps at random times) was seen as having some advantages but as I understand it the costs involved in keeping a useful number of ALBM's on air borne alert made the idea a non starter. I suspect in practice there would likely have been political issues with having aircraft carrying nuclear armed ALBM's on air borne alert in peace time, and I suspect a crisis or war time only air borne alert scheme might have been seen as to vulnerable to a bolt out of the blue surprise attack.
I suspect once SLBM accuracy levels began to approach ICBM accuracy levels and technology made communications with SSBN's easier that any residual perceived advantages of Intercontinental ALBM's were likely seen as simply not worth the bother.
I expect with a bit of work a search of DTIC or other sources would provide you with at least partial copies of various US cold war era studies that outlined the pros and cons of various basing schemes.
Maybe for a smaller rich country that already had SLBM's and Bombers and for what ever reason wanted to have ICBM's but didn't have the land to plausibly base them away from populated areas the idea might have made some sense (perhaps for some nations advanced SSBN technology might be harder to acquire or develop than ALBM technology and they might have concerns about the survivability or effectiveness of their SSBN force.)