Narrative:

I was not directly involved in this event; nor am I aware of what was coordinated between anyone. I was an observer. The aircraft had communication trouble. It appeared that instead of getting 7600 in the box; 7500 was entered. The datablock was showing [the incorrect information]. That was unable to be verified. It was apparent more than 20 miles from phl. The aircraft continued inbound to runway 35 and landed. It appeared that the pilot could transmit but not hear anyone. A light gun was used in the tower. I am unaware if the pilot saw the light gun. An aircraft was eventually scrambled [to intercept it]. However; aircraft X landed and was never intercepted. The scrambled aircraft got around 2 miles south of phl. There was a controller in charge in the tower. I am unaware if the local police were notified. It did not appear they met the aircraft at the general aviation ramp. Anyways; how was this aircraft allowed to fly right by the tower and land after appearing to be a [distressed] aircraft for at least 25 miles? I do not even know what to say about this incident. Why was management or whomever so confident that this was not a hijack with no way of confirming it? Why were they allowed to decide that nothing bad was going to happen? What did they base that on? If they were wrong and something went terribly wrong because it was an actual [hazard] how would that be explained to my family? How was this plane allowed to fly right by the tower with personnel in it? I realize is always better to be lucky than good but this incident is ridiculous. Phl continues to amaze me with its new circus acts.

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Original NASA ASRS Text

Title: PHL Tower Controller reported an aircraft was squawking 7500 when it actually had a radio problem. Reporter was concerned that the aircraft was allowed to land at a major airport.

Narrative: I was not directly involved in this event; nor am I aware of what was coordinated between anyone. I was an observer. The aircraft had communication trouble. It appeared that instead of getting 7600 in the box; 7500 was entered. The datablock was showing [the incorrect information]. That was unable to be verified. It was apparent more than 20 miles from PHL. The aircraft continued inbound to runway 35 and landed. It appeared that the pilot could transmit but not hear anyone. A light gun was used in the tower. I am unaware if the pilot saw the light gun. An aircraft was eventually scrambled [to intercept it]. However; Aircraft X landed and was never intercepted. The scrambled aircraft got around 2 miles south of PHL. There was a CIC in the tower. I am unaware if the local police were notified. It did not appear they met the aircraft at the general aviation ramp. Anyways; how was this aircraft allowed to fly right by the tower and land after appearing to be a [distressed] aircraft for at least 25 miles? I do not even know what to say about this incident. Why was management or whomever so confident that this was not a hijack with no way of confirming it? Why were they allowed to decide that nothing bad was going to happen? What did they base that on? If they were wrong and something went terribly wrong because it was an actual [hazard] how would that be explained to my family? How was this plane allowed to fly right by the tower with personnel in it? I realize is always better to be lucky than good but this incident is ridiculous. PHL continues to amaze me with its new circus acts.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.