Gulfstream G650
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown
ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Human Factors
This is to report an ATC incident flying on airway A466 in cruise and level at FL430 while approaching intersection AMDAR (which is on the northern FIR boundary of Afghanistan). The normal procedure is to call ahead 10 minutes prior to the Afghanistan boundary for entry permission.I have flown this route many times previously. The Controller has always been an American equipped with a strong and clear radio. On [this flight;] on initial contact I was answered by a male with a heavy accent using a weak radio and instructed to descend to 'thirty thousand' (not the correct phraseology - [should have been] 'flight level 300'). I refused the instruction saying we could climb if traffic was the issue. A few moments afterward the 'real' controller came on saying 'disregard'; maintain FL430; verify squawk and report position AMDAR.So be careful for bogus ATC instructions approaching the Afghanistan FIRs.
G650 pilot reported contact with an apparent interloper issuing bogus ATC clearances on the Afghanistan FIR frequency.