Su-27 at a USAF research centre !?!

In the wake of the dissolution of the Soviet Union, Ukraine and Blarus have repeatedly tried to sell their inherited Soviet aircraft to froeign countries at a relatively low cost.
According to some sources, a number of such deals were realised.
For instance, Belarus is known to have managed to sell two Su-27s to a USAF research centre , …

by Thomas Andrews from page 42 + 43 of the “International Air Power Review” Volume 8

Can anyone confirm this …. ???? I’ve heard of this rumour some time ago and I know that the USA managed to buy some of the Ex-Moldavian MiG-29s …. but? two Su-27s at a USAF research centre !???