Narrative:

A B737 landing runway 30R in the flare; asde-X alarmed with known vehicle on a closed taxiway putting up barricades. I should have sent the B737 around according to procedures. However; I saw the vehicle and it was not going on the runway and the B737 was so close to ground that issuing a go around would have been unsafe in this phase of flight.

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Original NASA ASRS Text

Title: STL Controller elected not to issue a go around to an Air Carrier about to flare when the ASDE-X alarmed apparently due to an airport vehicle operating on a closed taxiway.

Narrative: A B737 landing Runway 30R in the flare; ASDE-X alarmed with known vehicle on a closed taxiway putting up barricades. I should have sent the B737 around according to procedures. However; I saw the vehicle and it was not going on the runway and the B737 was so close to ground that issuing a go around would have been unsafe in this phase of flight.

Data retrieved from NASA's ASRS site as of July 2013 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.