Tower Controllers reported ground vehicles failed to communicate and follow hold short instructions resulted in taking evasive action to avoid landing traffic.
Synopsis
Tower Controllers reported ground vehicles failed to communicate and follow hold short instructions resulted in taking evasive action to avoid landing traffic.
Narrative
During this event I was working Ground Control; Clearance Delivery and Flight DATA. I was informed by Ops that a vehicle had crossed Runway XXR from Taxiway 1 and Taxiway 2 heading eastbound and joined the vehicles staged at Taxiway 2. Vehicle returned crossing XXR again at the same intersection heading westbound; narrowly missing the landing of a [priority handling] Aircraft X on RWY XXR. It was reported by Ops that the driver of the vehicle had to 'slam their brakes' to avoid a collision with Aircraft X. At no point in time during the two XXR incursions was the vehicle in communication with ground control or the local controller when utilizing the taxiways or crossing XXR. Vehicle was not visible from the tower due to nighttime conditions and no vehicle flashing lights were observed.Time of events as observed in ASCC (Airport Surface Surveillance Capability) playback:XA:40:32z - Vehicle 2 + 3 cross Rwy XXR at Taxiway 2 intersectionXA:41:07z - Vehicle 2 + 3 are clear of RWY XXR on Taxiway 2XA:41:24z - Vehicle target appears on ASCC on the West RampXA:41:53z - Vehicle crossed RWY XXR at Taxiway 2 eastboundXA:43:34z - Vehicle reappears on ASCC heading westbound attempting to cross RWY XXR and is within 200 ft of Aircraft X [priority handling] landing.XA:43:36z - Vehicle crosses RWY XXR behind Aircraft X and returns to the west rampThe second vehicles in this report were Aircraft Tow + 1. Tow was accompanied by another vehicle and exited the east ramp via Taxiway 4 and was instructed to proceed Taxiway 4 southbound and to hold short of RWY XXL. Tow acknowledged the transmission but failed to provide a correct readback. Tow proceeded southbound on Taxiway 4 and crossed RWY XXL without authorization and proceeded onto Taxiway 5. Local control had given a RWY XXL landing clearance to Aircraft Y. Tow +1 had cleared RWY XXL prior to Aircraft Y crossing RWY XXL threshold; as observed in the ASCC playback.Time of events as observed in the ASCC playback:XB:04:46z - Tow + 1 crosses RWY XXL at Taxiway 4 South intersectionXB:04:59z - Tow + 1 clear of RWY XXL on Taxiway 5XB:05:15z - Aircraft Y helicopter crosses RWY XXL landing threshold. Recommend all personnel/vehicles utilizing taxiways/runways be equipped with transponders; flashing lights and be in direct communication with the ground control or local control. Direct line to the fire department was OTS (Out of service) during the time of event. Fire department did not answer the crash phone. Due to low visibility at night; vehicle was not visible from tower.
Second reporter narrative
On Day 1 we had Aircraft X land at approximately XA:42Z after requesting priority handling. Aircraft X successfully landed and positioned itself on Taxiway 5 for inspection from response vehicles. After the response the aircraft remained on the taxiway; awaiting to be towed back its hangar.A vehicle; Tow; was dispatched from the East Ramp and authorized onto Taxiway 4 by the Ground Controller. Prior to me receiving a request from the Ground Controller for the vehicle to cross RWY XXL at Taxiway 4 (to proceed onto Taxiway 5); I was informed by the Ground Controller that the vehicle had crossed the runway without permission. We also received a call from a representative from Operations that they had witnessed the vehicle cross the runway without permission. Later on that evening I received another call from Operations at XB:31Z in which a representative questioned if I was aware of a situation involving a vehicle that had to slam on its brakes to avoid an aircraft. Unsure of any situation I asked for more questions and was told the event happened on Taxiway 1; and then told it was Taxiway 1/Taxiway 2 and that it occurred during the time of the earlier Aircraft X response. Later after receiving more information; I was informed that a vehicle potentially crossed RWY XXR at Taxiway 2 before and after Aircraft X landed; approximately XA:43Z. Immediately before and after Aircraft X landed I never authorized any vehicles to cross RWY XXR at Taxiway 2. Once the aircraft landed and began its taxi roll; control of the RWY was released to the Ground Controller.While I attempted to maintain a continual scan of the airfield there; during the Tow incident I was on dual positions; LC and CIC. It was nighttime and vehicles can be hard to see; especially those without flashing/strobe lights. Additionally; vehicles on our airfield are not equipped with transponders which would make them more identifiable on ground radar. The ground radar is also a new system for us which was certified recently. Recommendation: Ground vehicles should have transponders and flashing lights for visibility.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.