Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 33; Flight Crew Total 22000; Flight Crew Type 550
Confusion
ATC Issue All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued Advisory / Alert; Flight Crew Returned To Clearance
ATC Equipment / Nav Facility / Buildings; Aircraft; Human Factors
ATC gave us a block altitude between 8;000 FT MSL and 12;000 FT MSL between two radials northwest of TXK VOR. We were asked by Center to remain within 25 miles of the TXK VOR. We then set up; on the pilot's EFIS display; a visual picture of this area using the Navigational equipment on board. These instructions defined an area in which we could perform the required maneuvers for an FAA Type Rating Test. About 5 minutes later; the Controller angrily told us we were 31 miles from the TXK VOR and were guilty of drifting outside of the assigned area. Our onboard display showed our position well within the required 25 miles. We finished our training and returned to TKI without any further discussion with the Controller about distance from the TXK VOR.
DA2000 Captain is informed by ATC that he has drifted outside the designated airspace while doing maneuvers for a checkride. The on board display; which had been programed by the crew to remain withing the designated area; indicated that they had not drifted out.