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‘Confirming we are cleared to land?’ Who said what at Austin

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Re: ‘Confirming we are cleared to land?’ Who said what at Austin

#181

Post by hef19898 »

defrost wrote: post #154
hef19898 wrote: post #134

Earlier quoted context omitted.

It is still just changing vectors and speed in three dimensional space so...

I suggest you take your objections up with the authors of, say, A Four-Dimensional Space-Time Automatic Obstacle Avoidance Trajectory Planning Method for Multi-UAV Cooperative Formation Flight or any number of other similar papers. Many prefer to think of an objects path as a trajectory in space-time (four dmensions) and for two ojects to "collide" their paths must coincide within that 4-D space within an Epsilon for…

I never considered time as a 4th dimension in that sense. TIL.

Fun fact, now I can claim to plan in the 4th dimension by using lead times in supply chain planning!

Re: ‘Confirming we are cleared to land?’ Who said what at Austin

#182

Post by sfeng »

blitzar wrote: post #177
sfeng wrote: post #174

Earlier quoted context omitted.

It's very likely the Southwest pilots were completing a checklist, programming their flight computer, or some other minor pre-takeoff activity before being ready to takeoff. A minute just isn't all that much of a delay. If the controller needed it to happen immediately, they should have first asked if the plane was ready, and then should have issued a takeoff clearance with 'without delay' or 'immediate' in it. Only…

As a passenger that flys almost exclusively long haul from very busy airports, it is rare that my plane will come to rest on the runway, generally accelerating in the turn onto the runway and taking off.

Did they come to rest on the runway, or did they wait a minute at the side of the runway and then proceed to takeoff? I don't think you would notice the difference as a passenger, unless you were listening in on the ATC transmissions.

Re: ‘Confirming we are cleared to land?’ Who said what at Austin

#183

Post by taeric »

zaarn wrote: post #157
HPsquared wrote: post #155

Earlier quoted context omitted.

"Deterministic" only insofar as it's repeatable, but their behaviour is not predictable. If the behaviour is not predictable, how can it be validated as being correct?

If for a given set of inputs there is a deterministic output, then the overall behaviour to a series of inputs is just as deterministic and predictable. I'm not sure what you mean with "is not predictable" when you also admit that it's repeatable.

I think the point is that reality is essentially a chaotic system. That is, yes, you can repeat a failure from an input once you've seen it, but the search space is too big to enumerate beforehand.

Re: ‘Confirming we are cleared to land?’ Who said what at Austin

#186

Post by Xcelerate »

I know nothing about ATC, but to be blunt, it sounds like the controller is absolutely not paying attention and possibly even distracted with something else throughout most of the video until they realize there is a near-collision. Is there video footage of the control room that will be reviewed?

Re: ‘Confirming we are cleared to land?’ Who said what at Austin

#187

Post by mulmen »

jnsaff2 wrote: post #165

I got my PPL in EU and here it was drilled into me that in Europe there can be exactly ONE plane cleared to use a runway at any time. When the approaching plane is cleared then there is no allowance for anyone and anything to be on the runway. So if there is a departing plane waiting on the runway or someone crossing then the approaching plane is given "cleared approach runway 08" but never "cleared to land". Which a…

Europe uses pessimistic runway locks but the US prefers optimistic locks. This improves throughput at US airports with the risk of a rollback on a dirty runway.

Re: ‘Confirming we are cleared to land?’ Who said what at Austin

#188

Post by AdamN »

bilekas wrote: post #144
SQueeeeeL wrote: post #142

Earlier quoted context omitted.

I'm not sure how many people know this, but one of the first instances of "union busting" ever committed by the US federal govt was against air traffic controllers. The job used to be extremely competitive and prestigious, but overall lower wages and security has made it way harder to attract as many highly talented individuals. And with how many rules there are in that pdf, it's shocking we don't see multiple accide…

I don't knock unions but I will add : > The median annual wage for air traffic controllers was $129,750 in May 2021 SOME unions do take advantage, given the traffic controllers' 'single point of failure' it can be very attractive for some unions who are greedy. Again I reiterate, unions are not a bad idea, just not all of them are solely in the interests of the actual employees.

That's not some statement unique to unions. Every organization suffers from the principal-agent problem and every union has a tension between what the union wants, what it's officers want, and what the members want. Also, there's nothing wrong with greed: it's one of the prime human motivators and is encourage in capitalist/individualist societies.

Unions are frequently reasonably well aligned and sometimes not.

There are many solutions like government mandated elections of the officers, rotation of the officers, multiple unions for a given sector or company or factory, etc... Each solution of course comes with a cost including weaker officers coming in, dilution of the power of the union, etc...

This pattern also exists for governments, transnational organizations, corporations, non-profits, etc... and it doesn't make them bad or good or greedy or saintly - it just is the nature of any group.

Re: ‘Confirming we are cleared to land?’ Who said what at Austin

#189

Post by twawaaay »

F for Southwest and the tower for lack of awareness, big fucking A+ for FedEx guys for babysitting everybody around.

I think one problem with the radio communication is that because of its terse and scripted nature all of the emotion is removed and it does not convey the urgency.

I can imagine the apprehension of FedEx pilots when they asked "confirming we are cleared to land Runway 18 Left?". I can also understand why the controller just treated it as one of the million other question of the same type without ever catching there is anything wrong here.

Re: ‘Confirming we are cleared to land?’ Who said what at Austin

#190

Post by AdamN »

_cenw wrote: post #179
camgunz wrote: post #164

Earlier quoted context omitted.

Not to be snarky, but these last couple close calls in the US feel like indication to me.

In 2020, ATC directed an incoming United 787 on the wrong runway at Paris-Charles de Gaulle Airport. The only reason nothing terrible happened is that the Easyjet pilot on the wrong runway called for go-around after looking out the window, moments before the would-be collision. Didn't make it beyond aviation news, probably because recording ATC is not allowed in France. Human error will creep up everywhere, all you c…

ATC cannot be recorded? Where else is that the case?
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