Dubai near disaster..?
According to the raw data received from the Mode-S transponders from both aircraft:
- at 18:04:04 EK-568 had already passed the hold short line M5A but was still short of the runway edge at position N25.2576 E55.3616
- at 18:04:05 EK-524 had reached 102 knots over ground at position N25.2500 E55.3767 while accelerating on runway 30R.
- at 18:04:15 EK-568 was at position N25.2582 E55.3620 crossing the runway centerline
- at 18:04:19 EK-568 had crossed the other runway edge and was now on taxiway N4 between runway edge and hold short line N4 at position N25.2586 E55.3623
- at 18:04:24 EK-524 had slowed to 24 knots over ground again at position N25.2537 E55.3702
- at 18:04:04 EK-568 had already passed the hold short line M5A but was still short of the runway edge at position N25.2576 E55.3616
- at 18:04:05 EK-524 had reached 102 knots over ground at position N25.2500 E55.3767 while accelerating on runway 30R.
- at 18:04:15 EK-568 was at position N25.2582 E55.3620 crossing the runway centerline
- at 18:04:19 EK-568 had crossed the other runway edge and was now on taxiway N4 between runway edge and hold short line N4 at position N25.2586 E55.3623
- at 18:04:24 EK-524 had slowed to 24 knots over ground again at position N25.2537 E55.3702
Nice graphic.
A quick bit of back-of-the-envelope arithmetic, based on a couple of additional runway points in the data, would suggest that groundspeed at the point where the RTO was initiated could have been of the order of 140 kts.
A quick bit of back-of-the-envelope arithmetic, based on a couple of additional runway points in the data, would suggest that groundspeed at the point where the RTO was initiated could have been of the order of 140 kts.
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RWSL have their uses maybe but of far more Importance here is a complete analysis of the human factors involved. I have grave concerns that these will be addressed given the employers history though.
Not a bad idea about the landing lights though. I quite that about the USA
Not a bad idea about the landing lights though. I quite that about the USA
Not absolving any of the guilty from blame, but I do not fathom why is it necessary to give taxi instructions that involve crossing the active runway when there are at least two perfectly feasible (and possibly shorter) tracks to the departure threshold that do not require a runway crossing. Maybe not direct, but certainly a contributing cause. EK524 took the direct route, so clearly they did not have a mental image of possible departing traffic crossing ahead of them.
Unlike the one that just missed the houses at the other end of the runway, you can see how this could happen. Crossing, I look both ways, check TCAS and listen out (not that they’d have heard a takeoff clearance in this instance) but am aware of how vulnerable you can be. Same with entering: I verbalise “line up ONLY” whether I’m PF or PM, but I sometimes get a moment of doubt half down the runway if we had clearance or not.
I have been impressed by RWSL whenever I’ve encountered them - no way would you set off by mistake. I’d have thought DXB would have installed them by now?
I have been impressed by RWSL whenever I’ve encountered them - no way would you set off by mistake. I’d have thought DXB would have installed them by now?
Airmann wrote,
”What needs to change is that it should become standard procedure that aircraft only turn on thd landing lights once starting T/O role, as opposed to when entering the runway. This is the best indication for pilots crossing.”
On the surface this sounds like a good idea, but remember the accident at LAX in 1991 where USAir 1493 a 737 landed on top of a Metroliner awaiting takeoff clearance on the runway. If memory serves me right, the Metroliner’s lights were washed out by the centerline lights and the arriving 737 didn’t see it on the runway and landed on top of it. If the Metroliner had all their lights on while holding short, this accident may have been averted. It’s also why I don’t line up exactly on centerline when I’m told to “line up and wait” with another aircraft on approach to the same runway. If I offset my jet a few feet the lights of my jet won’t align with the runway centerline lights and might be more easily seen at night by an approaching aircraft.
”What needs to change is that it should become standard procedure that aircraft only turn on thd landing lights once starting T/O role, as opposed to when entering the runway. This is the best indication for pilots crossing.”
On the surface this sounds like a good idea, but remember the accident at LAX in 1991 where USAir 1493 a 737 landed on top of a Metroliner awaiting takeoff clearance on the runway. If memory serves me right, the Metroliner’s lights were washed out by the centerline lights and the arriving 737 didn’t see it on the runway and landed on top of it. If the Metroliner had all their lights on while holding short, this accident may have been averted. It’s also why I don’t line up exactly on centerline when I’m told to “line up and wait” with another aircraft on approach to the same runway. If I offset my jet a few feet the lights of my jet won’t align with the runway centerline lights and might be more easily seen at night by an approaching aircraft.
Last edited by Chiefttp; 14th Jan 2022 at 00:46.
That makes a lot of sense - I suspect you're not the only one. Was flying EK A388 as pax the other night and noticed on line up the airframe was not centred and at an angle while lined up and waiting. Straightened out smoothly with minimal power before applying t/o thrust. Seemed intentional.
Paxing All Over The World
A pax here: Are there many airports in Europe with this equipment? I doubt at any in the UK but I might be too cynical about cost.
The only airport I’ve come across with them in Europe is Paris CDG. They have every landing aircraft needing to cross an active departure runway, so the RWSL system is a huge safety net in CDG. In the UK very few airports (off the top of my head) have a departure runway where crossing traffic is a common sight.
Maybe this will be a wake-up call for airports around the World to invest in RWSL? It comes into its own in poor vis, and is also completely autonomous.
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And that's the key. Every airport doesn't need the system, it's those that have designs that require constant crossing of active runways. Some only need it on a few runways e.g. LHR only needs it on the southern runway.
Not really, the main issue at hand is aircraft crossing an active departure runway. So crossing whilst an aircraft has commenced it’s takeoff roll.
RWSL wouldn’t do anything at MAN with 23L, no aircraft cross that runway. They cross 23R which in that configuration is for landing only, when the pilots have a clear view of the runway and the RWSL system wouldn’t make a difference.
RWSL wouldn’t do anything at MAN with 23L, no aircraft cross that runway. They cross 23R which in that configuration is for landing only, when the pilots have a clear view of the runway and the RWSL system wouldn’t make a difference.
Although many aspects are good, there is one potential problem with some of the suggestions about RWSL, particularly if it is only installed at an airport where it is perceived that 'there is a need'. The mindset with RWSL is that when the red lights are off, we can cross/roll, when you then arrive at an intersection or line up on a runway where there is no need, at least half the protection of the system is lost. There is an additional gotcha if you are used to operating from airports with RWSL and then find yourself somewhere with a less sophisticated system, the usual mindset can be a problem.
I've also got a slight hesitation about the control systems, which are driven by ASMGCS data, and rules about when the RWSL is activated - having had some involvement in setting up RIMCAS (Runway Incursion Monitoring and Alerting System) at a pretty simple airport, getting the rules correct so there are no false alerts is not easy. With RIMCAS, the alerts are 'only' raised to ATC and humans can assess whether the alert is legitimate, although there is often little time for this (or, worse, an alert is ignored because 'it always goes off when this happens'), RWSL, as I understand it, is fully autonomous - the system is most useful at complex airports where the ruleset which does not produce erroneous operation will be difficult to compile. And then, of course, one day ATC will say, "Ignore the THLs, clear for take-off". The tech-savvy will now start talking about AI......
I've also got a slight hesitation about the control systems, which are driven by ASMGCS data, and rules about when the RWSL is activated - having had some involvement in setting up RIMCAS (Runway Incursion Monitoring and Alerting System) at a pretty simple airport, getting the rules correct so there are no false alerts is not easy. With RIMCAS, the alerts are 'only' raised to ATC and humans can assess whether the alert is legitimate, although there is often little time for this (or, worse, an alert is ignored because 'it always goes off when this happens'), RWSL, as I understand it, is fully autonomous - the system is most useful at complex airports where the ruleset which does not produce erroneous operation will be difficult to compile. And then, of course, one day ATC will say, "Ignore the THLs, clear for take-off". The tech-savvy will now start talking about AI......
Not really, the main issue at hand is aircraft crossing an active departure runway. So crossing whilst an aircraft has commenced it’s takeoff roll.
RWSL wouldn’t do anything at MAN with 23L, no aircraft cross that runway. They cross 23R which in that configuration is for landing only, when the pilots have a clear view of the runway and the RWSL system wouldn’t make a difference.
RWSL wouldn’t do anything at MAN with 23L, no aircraft cross that runway. They cross 23R which in that configuration is for landing only, when the pilots have a clear view of the runway and the RWSL system wouldn’t make a difference.
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Fact: There have been more collisions and near misses on runways than in the air.
So, where is RTCAS? (Runway Traffic Collision And Avoidance System). It needs to be an onbaord system. Going forward, ICAO should demand all runway lighting is LED and have the edge lights turn red when there is crossing traffic.
So, where is RTCAS? (Runway Traffic Collision And Avoidance System). It needs to be an onbaord system. Going forward, ICAO should demand all runway lighting is LED and have the edge lights turn red when there is crossing traffic.
It sometimes seems strange that despite such levels of automation, redundancy and independent checking by multiple different systems on both aircraft and ATC, designed to catch even fantastically unlikely errors, some absolutely critical information is transmitted between the two by voice alone. And then it’s held in short term memory in human wetware before being being fed into a/c systems.
couldn’t there at least be a status flag on both a/c and ATC showing released for takeoff or not?
couldn’t there at least be a status flag on both a/c and ATC showing released for takeoff or not?