Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Last 90 Days 138
ATC Issue All Types; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Ground Equipment Issue
Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification
ATC Equipment / Nav Facility / Buildings
During arrival into HPN; I noticed the PAPI seemed different. After a few moments I realized that the light indications were backwards. The PAPI for 16 is on the left hand side of the runway but the red lights began on the left (farthest two lights from the runway were red).  The FAA requirements per FAA AC150/5340-30G Chapter 7.4 (d) are that the 'light housing assemblies nearest the runway (inboard) must be seen as red and the two farthest from runway (outboard) must be seen as white.' The VGSI (visual glideslope indicator) was at a corresponding angle to the ILS glideslope which we were using as a backup; despite the red and white being 'flipped'.  I wasn't sure the reference and didn't want to address my concern without being certain and without a reference so I did not immediately notify operations. In addition to my hesitation that evening; the Tower closed just a few minutes after we parked at the gate. The next morning when I arrived to the aircraft; I asked for a contact number for the Tower and gave them a call. The Controller who answered seemed helpful and keen on ensuring that the issue would be resolved. Controller said they would send OPS out to check on the system. Address with HPN operations to resolve the PAPI indications.
Pilot reported the PAPI's at HPN Runway 16 being reversed.