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by bombcar 88 days ago
Emergency vehicles almost always can override/ignore warning devices (think firetrucks running red lights) which can cause "fun" for some value of "death/dismemberment/vehicle loss".

https://www.youtube.com/watch?v=A0Xf7aU5Udo

4 comments

Airport emergency services are presumably trained in this, but since a plane cannot stop easily (or not at all on takeoff after V1), I seem to remember the general rule is that even emergency vehicles with lights and sirens on give way to planes, and don't enter runways without permission from the tower.

In the audio released by the BBC, the fire truck DID get permission from the tower to cross something, I can't tell if it was the runway in question. However, to cross the red runway lights if lit, you normally need that spelled out too something like "truck one, cross four delta, cross red lights". This did not happen on the BBC audio, which could mean one of many things.

They got clearance, which was overruled by a STOOOP!

The guy was alone operating 2 frequencies, had an emergency of another aircraft going on… is not so easy as many commenters from the armchair are insinuating

They got clearance and then obviously didn't bother to look outside, which is a dereliction of the basic responsibility of operating any vehicle on an airport surface. Clear left, clear right, then cross the hold short line.

(See my other comment below if you're tempted to say something about visibility.)

They could not see, because delta crosses in diagonal to the runway, such that the plane comes from behind (and the right side) so the driver has no chance to see. The truck was moving fast which is ok, because you want to clear the runway as fast as possible.
It doesn't matter what the orientation of the taxiway is. If you can't see when you're stopped straight on the taxiway centerline, you stop at an angle instead.

There is never an excuse for not visually clearing a runway before entering it.

Then peak your head out of the window, that’s not an excuse.
From where I'm sitting, it's not really "the fault" of ATC (even though it is) simply because I'm not trusting enough of ATC even when they're on "my side".

When cleared across a runway I'm still going to be looking in all directions, and proceed as fast as I can. I also look both ways at railway crossings even if the guards are up and silent.

I wonder if visibility was good enough that looking both ways before crossing the runway would have prevented this.
That'll be one of the things the NTSB investigates.

I also wonder if you're down to a "one controller" scenario if it would be better for there to be once frequency, not a ground/air split.

Or perhaps a "one controller" scenario is just terrible policy.
No. it wasn't. Delta crosses 04 in diagonal, so basically they should have taken the head out of the window and look behind. They had the clearance, so they just tried to cross. The problem is for some reason they did not hear the "Truck 1 stop" call.
>The guy was alone operating 2 frequencies, had an emergency of another aircraft going on… is not so easy as many commenters from the armchair are insinuating

I'm not saying its easy, I'm actually specifically saying it's such a hard job we should have automated most of it away ages ago. If the only thing stopping an accident like this is an ATC employee, this _will_ happen in the future.

They came up with rail signals long before the idea of a computer even existed. It's hard to believe voice only communication of routes and runway access is the best path forward. Especially when passenger airliners are involved.

Automation emboldens policy makers to reduce human count because of the perceived increase in safety. This results in less eyes and brains monitoring for situations of automation failure or abnormalities. The corner stone of aviation safety over the last several decades has been having multiple, highly trained and experienced operators on station monitoring aviation systems to catch those moments when something goes wrong. Additionally, a culture where those operators are encouraged to speak up and be heard when something goes wrong without fear of being reprimanded is essential.

Automation is fantastic. We use it extensively in aviation. However, the long tail of 9s in reliable requires constant vigilance and oversight because anything that can go wrong will.

Who's entering the signal that the runway is locked? What if they screw up?

There are so many failure modes with vehicles and planes using the same tarmac that I fail to see how anything would be worth developing here that doesn't eliminate that requirement altogether.

Currently it’s automated at this airport: https://www.faa.gov/air_traffic/technology/rwsl

Presumably this is lack of familiarity with this on the part of firefighters.

Ah, okay. I suppose it'll be part of the investigation but I wonder if the RELs were indiciating an unsafe runway which prompted the firetruck to ask or if they always ask for permission. Either way, I think my assesment is still correct: there are a lot of edge cases that neither lights nor humans are going to stop. O'Hare apparently has tunnels/underpasses for ground vehicles to use which seems basically foolproof for avoiding collisions like this.
From the FAA’s site [1] on RWSL:

> 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. (ex.: "Orlando Ground, Ops 2 is holding short of runway 36 Left at Echo due to red lights").

Airports are highly controlled environments unlike typical motor vehicle roadways and generally the same rules apply for aircraft, vehicles, and equipment on airport surface movement areas. From all sources I can find, if the RWSLs were working they should have been red and nobody should have entered the runway without further clarification from ATC.

[1] https://www.faa.gov/air_traffic/technology/rwsl

All vehicles can override/ignore warning devices. Doesn't make it right. Emergency vehicles should not override/ignore train or plane crossings. Trains and Planes don't care about flashing lights. Crossing an active runway requires clearance for safety.

In this case, from the available information, the drivers of the fire truck thought they were cleared, and proceeded to cross while a plane was cleared to land. I'm not familiar with ATC ground radio to know if they were actually cleared or not, but it seems clear that that the drivers thought they were cleared.

Investigation reports will give us more details.

Anyone can override if needed, not just emergency personnel.

However that is not permissible here. Airplanes are similar to trains, you have to stop and wait and there are no exceptions.