According to the project, at an altitude of ten thousand metres the carrier was to make a "slide" with separation from the aircraft "shuttle" at the time of descent.

Advantages of MAKS were considered: absence of tie-ups with the spaceport, possibility of rescuing crews on space objects, and high-altitude reconnaissance.

[5] The 6-month Joint Study Program was carried out concurrently in the Soviet Union and the United Kingdom, with data and analyses shared between the two organizations, leading to the design of the An-325.

When compared to vertical launch, the implementation of this project promised a fourfold decrease in the cost of orbital payload placement.

In addition to other things, HOTOL could more efficiently address the issue of getting crews to orbital stations and removing them from there in an emergency.

[2][6] In the case of Interim HOTOL, it would be carried by the An-325 during an approximately hour-long flight to an altitude of 9 km and the proper release point would be reached after liquid hydrogen/liquid oxygen was supplied to the Orbiter on the ground.