Я не переводчик авиационной тематики.

I do not see that отработка means "testing". It is probably "development".

aero servo elasticity is a technical term. - Google Search

Multitran shows: трёхстепенной стенд поворотаtotal-freedom tilt rig (испытываемого объекта по трем степеням свободы)

So I would say:
Three-stage test stands have a high level of dynamic and positional accuracy. The control signals used are accurate to the arcminute.