I’d love a source indicating it’s permissible to override the RWSL for emergency vehicles. In all training materials I’ve seen for pilots, it’s clear that an ATC clearance does NOT permit overriding the RWSL indication precisely for this scenario where ATC inadvertently provided a bad clearance. The direction to pilots is to query the controller to give them a chance for a second look and trap the error of the incorrect clearance. I linked the FAA page in another post where it provides direction to ground vehicles as well. Tomorrow I will have more time to research but this might be one of those things buried in a difficult to find Advisory Circular or something.
From what I've found it seems like the indication of the RWSL should match the clearance from ATC. This to me suggests a ground vehicle is permitted to request:
> • DO NOT proceed when the Runway Entrance Lights have extinguished without an Air Traffic Control clearance. Runway Status Lights verifies an Air Traffic Control clearance, it DOES NOT substitute for an Air Traffic Control clearance.
> • If an Air Traffic Control clearance is in conflict with the Runway Entrance Lights, do not cross over the red lights. Contact Air Traffic Control and advise that you are stopped due to red lights.
The page never directly states it¹, but the implication is that a ground vehicle can request clearance, and the clearance from the ATC can be granted, & RWSL should match. If they do not match, red RWSL prevails, and green RWSL are not a substitute for clearance.
Truck 1 did request clearance. So then the question for this incident would be "what was the status of the RWSL when Truck 1 entered the runway?"² If they were red, according to the linked page, Truck 1 should not have entered the RW regardless of the clearance, and the mismatch between ATC verbally granting clearance & the RWSL system seems problematic. But, I don't know what the actual status of the RWSL was, so.
… hopefully, the NTSB report in a few months will contain an explanation.
¹I am treating this page as a non-authoritative explainer, not as legal regulations.
²The one video I've seen of the incident is not clear enough for me to make out the RWSL.
This was an emergency vehicle actively responding to an emergency, not a regular vehicle. I'm not sure if that changes SOP but it certainly seems worth considering.
