Open Skies

[pilotcpb]

Was on approach to Halifax a few days ago, heard the callsign "open skies" used by a gent with an eastern european accent. Are these the military guys who fly observation missions on behalf of the open skies treaty? I did not get a chance to ask ATC the aircraft type.

[Itswindyout]

or Ocean Sky perhaps

a Russian / UK based corporate charter operation. ?

[slatch]

Yes, a Russian TU-154, unarmed aircraft certified in accordance with Treaty provisions.