NASA CALLBACK REPORT: A pilot reported that he used GPS successfully to navigate to a distant point on an IFR flight plan ? but ran afoul of the FARs in the process:
IFR flight plan filed on airways [with] equipment Code/A. Aircraft equipped with 2 VFR GPS units, with current database. Requested and received vectors (radar) for a short-cut on the route. Controller asked if I had GPS. I replied “VFR” GPS. Used GPS to aid navigation to vector fix. When handed over to next Center controller, he rerouted my flight plan and current radar vector to a quite distant VOR fix. All was going well until we were handed over to Approach, who complained that we were filed equipment /A but were flying to a distant fix on GPS navigation. He said I should have refused the unsolicited rerouting by Center. I remain confused, as it?s my understanding that using any GPS as an adjunct to flying an assigned radar vector to a fix is legal. Nothing dangerous occurred. Conditions CAVU, VMC, continuous radar contact.
IFR equipment rules apply to all conditions under which instrument flights may be made, including CAVU. According to Section 5-1-7(a)3 of the current Aeronautical Information Manual, the /A notation on an IFR flight plan indicates that the aircraft has transponder with Mode C capability only. The /G notation indicates that the aircraft is GPS/GNSS equipped with enroute, terminal, and approach GPS capability.
The reporter erred twice ? in requesting a route short-cut using VFR-certified GPS on an IFR flight plan; and in accepting the Center controller?s reroute to the distant fix. The Center controller in this case should not have approved the direct reroute, since the pilot legally should have had IFR-certified GPS on board in case radar coverage was lost.
NASA ASRS Reprint