A young French skeptic, who reads (skeptically) the UFO review OVNI
Presence (O.P.), sent me the following excerpt from an August 92
issue of this review (R.G. = Robert Galley, French minister of
defense in 1974, answering about the Belgian UFO wave):

"O.P. : Can you conceive that the U.S. could allow themselves to send
 their most modern crafts over foreign territory, with the Belgian
 hierarchy ignoring that ?"
"R.G. : Absolutely ! The best proof which I can give is that, some time
 ago, without informing the French authorities, the U.S. based in
 Germany sent a plane to make photos of Pierrelatte (*). We followed
 this plane, and, after its landing on the Ramstein airport, Colonel X
 got back the shots of Pierrelatte. The U.S. had not informed us..."
(*) There is an important military plant of enrichment of uranium at
Pierrelatte (Drome).

What kind of plane could it be ? Surely not an SR-71, which our planes
could not follow (and still can't)...