Flight Crew Air Transport Pilot (ATP)
Confusion
ATC Issue All Types; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Airport; Chart Or Publication
We were cleared a visual approach to 9R; and upon asking; were re-cleared to land on 9L. We had briefed the approach before the descent into PHL. Our logic was with reduced traffic we had a chance of getting it; thus shortening taxi in and saving gas. Once Tower cleared us to land on 9L; we side-stepped over to land. We conducted a visual approach because the ILS was not turned on. Runway 9L has REIL's and MALSR lighting. Runway 9R has PAPI's and ALSF-II; with the PAPI's on the right side of the runway. In between the runways; and this is the problem; there is some kind of airport structure or antennas or something with horizontal red and white lights that give the appearance of a PAPI. We were unable to distinguish what exactly it was on short final in the dark while focusing on landing. From a long way out on a visual approach it gave us the mis-perception that we were on a valid glide path; but it is not a PAPI. This caused confusion to us as a crew because it was not the picture that was briefed; the lights are in an abnormal position in relation to the runways; and there is no descent guidance whatsoever in these lights. We ended up slightly high but not so high that only a small correction was needed to execute a safe; uneventful landing. In less than perfect visibility; an aircrew might be misled into a dangerous approach. All the lights in this structure need to be red and a note on a safety page or the 10-9 or approach plate. Proper diagramming on the 10-9 would work too.
Air carrier Captain reported seeing and following a set of horizontal lights which appeared to be PAPI between two parallel runways at PHL. On short final; the crew determined these were not PAPI lights and they gave the misperception of being on a valid glide path.