A B737-300 captain had to brake abruptly for two; apparently authorized; suv type vehicles crossing ...

Narrative:

As we were approaching taxiway a; I observed two vehicles (in trail) approaching from our left perpendicular to our movement. It appeared they were not going to stop to give way. I began to slow (estimate speed at six to eight knots) when the vehicles stopped abruptly at the designated stop marker. I then continued my taxi and was approaching the vehicular road way parallel to taxiway a when the vehicles accelerated toward us. Anticipating a collision; I retarded the thrust lever and applied the brakes. The aircraft stopped abruptly; but not harshly. I set the parking brake. The two vehicles also stopped; reversed quickly; and repositioned behind the 'stop' marker. The pm advised ground control of the incident while I queried the flight attendants about the cabin. The flight attendants informed me they were all seated during the incident and were okay. I took a picture of the vehicles from the cockpit but was unable to read the license plate. The vehicles were white cherokees with dual amber lights on the roof (the lights were not on.) on the side of both vehicles was [a sign identifying them as commercial security vehicles.] the pm made a PA to the passengers informing them of the reason for the stop. [After landing] I spoke with the lead flight attendant after deplaning the passengers. He informed me one passenger mentioned she had some discomfort from the stop.

Original NASA ASRS Text

Title: A B737-300 Captain had to brake abruptly for two; apparently authorized; SUV type vehicles crossing their path who initially failed to give right of way to the aircraft.

Narrative: As we were approaching Taxiway A; I observed two vehicles (in trail) approaching from our left perpendicular to our movement. It appeared they were not going to stop to give way. I began to slow (estimate speed at six to eight knots) when the vehicles stopped abruptly at the designated stop marker. I then continued my taxi and was approaching the vehicular road way parallel to Taxiway A when the vehicles accelerated toward us. Anticipating a collision; I retarded the thrust lever and applied the brakes. The aircraft stopped abruptly; but not harshly. I set the parking brake. The two vehicles also stopped; reversed quickly; and repositioned behind the 'stop' marker. The PM advised Ground Control of the incident while I queried the flight attendants about the cabin. The flight attendants informed me they were all seated during the incident and were okay. I took a picture of the vehicles from the cockpit but was unable to read the license plate. The vehicles were white Cherokees with dual amber lights on the roof (the lights were not on.) On the side of both vehicles was [a sign identifying them as commercial security vehicles.] The PM made a PA to the passengers informing them of the reason for the stop. [After landing] I spoke with the lead Flight Attendant after deplaning the passengers. He informed me one passenger mentioned she had some discomfort from the stop.

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.

Attributes
ACN	1106458
Time
Date	201308
Place
Locale Reference	BWI.Airport
State Reference	MD
Aircraft 1
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	Taxi
Flight Plan	IFR
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 213 Flight Crew Type 11000
Events
Anomaly	Conflict Ground Conflict Critical

A B737-300 captain had to brake abruptly for two; apparently authorized; suv type vehicles crossing their path who initially failed to give right of way to the aircraft.