Flight crew flying 737NG aircraft received alert from air traffic control on approach.

Attributes
ACN	1762841
Time
Date	202009
Local Time Of Day	1801-2400
Place
Locale Reference	LGA.Airport
State Reference	NY
Environment
Light	Night
Aircraft 1
Make Model Name	B737 Next Generation Undifferentiated
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Route In Use	Visual Approach
Flight Plan	IFR
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 91 Flight Crew Type 91
Events
Anomaly	ATC Issue All Types Deviation - Procedural Published Material / Policy Inflight Event / Encounter CFTT / CFIT

Narrative:

We were doing the RNAV visual to runway 31. Weather was not a factor. Autopilot was on; everything was set; stabilized; on path; pretty much a perfect approach; or so we thought. VASI was also red over white; so from our end there was nothing wrong. Tower gave us a low altitude alert asking us to check our altimeter setting immediately. We had no GPWS (ground proximity warning system) warning; like I said we were right on profile. My concern is; why did the tower give us that alert? If we got that alert; shouldn't every company aircraft flying the RNAV visual to 31 get the same alert? Is there something wrong with the procedure? Their equipment? Or did we make a mistake? If we did; we don't know what we could have done differently. Could you guys look into this? Is lga handing out this warning to everyone? Because if we received this alert based on what we were doing; then everyone landing on 31 on the RNAV should be in the same place altitude and position as us plus or minus 10 feet?

Original NASA ASRS Text

Title: Flight Crew flying 737NG aircraft received Alert from Air Traffic Control on approach.

Narrative: We were doing the RNAV Visual to Runway 31. Weather was not a factor. Autopilot was on; everything was set; stabilized; on path; pretty much a perfect approach; or so we thought. VASI was also red over white; so from our end there was nothing wrong. Tower gave us a low altitude alert asking us to check our altimeter setting immediately. We had no GPWS (Ground Proximity Warning System) warning; like I said we were right on profile. My concern is; why did the Tower give us that alert? If we got that alert; shouldn't every Company aircraft flying the RNAV Visual to 31 get the same alert? Is there something wrong with the procedure? Their equipment? Or did we make a mistake? If we did; we don't know what we could have done differently. Could you guys look into this? Is LGA handing out this warning to everyone? Because if we received this alert based on what we were doing; then everyone landing on 31 on the RNAV should be in the same place altitude and position as us plus or minus 10 feet?

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.