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Comment by michaeljx | Hacker News Reader

From what I understand, despite the tower not being able to create a gap for 30+ minutes,which although extreme may be understandable due to SFO being the way it is, another major factor was the fact that the tower was unable to provide a realistic estimated time to enter the circuit. That is completely unacceptable.

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If you mean “traffic pattern” (from https://www.faa.gov/air_traffic/publications/media/pcg_10-12...), that is also something you would do visually, which I don’t think Lufthansa would accept.

As for not being able to give an accurate estimate, that is not for the on-the-radio approach controller to calculate, given their view of the airspace. The video posted by parent shows how long the inbound flows were (at least on the east side); approach wouldn’t have seen that.

The coordination necessary to get an accurate estimate should’ve involved managers, which might be affected by the current shortage (see https://www.npr.org/2023/11/09/1211838624/air-traffic-contro...).

I meant for the ATC to provide a descent estimate of when Lufthansa should be expected to enter the AERODROME TRAFFIC CIRCUIT (since you want tolink the FAA glossary) in order to land (they had them on a hold pattern for 35+ minutes). This is independent of whether the approach is IFR or VFR. A TOWER controller has all the information necessary to calculate that estimate, and should be expected to do so, the same way a stock trader is expected to calculate PnL of their positions on the fly given the current stock price.

Most of the queue would have been with approach, not tower. The aircraft sequenced to land were split across at least two controllers, tower and approach, and possibly more than one approach controller depending on how SFO splits them up. I would expect approach to be able to provide a reasonable estimate but it seems like in this case the estimate was found to be four minutes off, which seems totally within the bounds of a reasonable estimate from an approach controller.

The traffic pattern (US term) isn't really a factor here either way, airliners flying visual still usually use charted routes (like the instrument procedures) or radar vectors rather than the pattern. Remember that the pattern is only about one mile out from the field. By the time airliners are that close they're probably cleared.

> but it seems like in this case the estimate was found to be four minutes off

No, I don't think you are being at all accurate about characterizing that; maybe you lost count of the delays. After being told to wait ten more minutes, the pilots waited an extra four minutes before pressing for an update, and got told to wait another 10-15 (or f off).

Aerodrome traffic circuit is the ICAO term for traffic pattern, which is it what it is called in the US (it may be in the glossary but the point is that manual uses "traffic pattern" repeatedly). And this "traffic circuit" you refer to is almost always a VFR thing, as IFR approaches use specific charted procedures that generally do not end with a traffic circuit.

https://skybrary.aero/articles/aerodrome-traffic-circuit

Aerodrome traffic pattern is completely different from holding patterns. And this is what LH was instructed to do, keep holding. Holding patterns are published for all airports and usually planes are stacked on those holding patterns and they are emptied FIFO style. Busier airports have multiple holding patterns to accommodate a large number of aircraft in case of on ground emergencies.

Sure, but GP stated wrt traffic patterns, "This is independent of whether the approach is IFR or VFR." which is not the case. For IFR, as was the case here, the LH was looking to execute an IFR approach, not ever enter the aerodrome traffic circuit.

> that is not for the on-the-radio approach controller to calculate

In that case they should not have given an estimate in the first place if it's just made up

That's why it is called an estimate. It is how much you think it might take, not the exact amount of time.

When asked about how long something it is going to take, everyone is given an estimate, not an absolute value. And this is because a lot of things can happen in between that are out of everyone's control.

I found that part delightfully ironic, because it's basically a meme that whenever a flight is delayed ground staff/pilots will always tell passengers "we'll just be off in just a few minutes" over and over again regardless of how long the delay is going to be.

The controller tried to give an estimated time, but that original estimate was blown out of the water by the other planes in the queue taking longer than expected, and the controller didn't have time to keep trying to give an updated estimated time to the one plane in the queue that wanted to do things the hard way (that also, due to circumstances within its own control, departed its original airport late and arrived outside of the window where SFO could have accommodated its silly request without any delays).

Your framing here is weird and doesn't match the facts. The airplane didn't want to do anything. Its pilots were following a mandatory company safety policy.

My framing here is literally based on the transcript of the conversation between the pilot and ATC.

Its pilots were following a mandatory company safety policy.

This is not true, because if it was true the pilot would already have diverted to Oakland per "mandatory" company "safety" policy when he was first told that they would not be able to accommodate his non-standard request to disrupt the twenty plus planes that were already in the queue.

It's not the ATC's fault the pilot didn't manage his plane's schedule properly.

> first told that they would not be able to accommodate his non-standard request

Now you are just making things up. Please go take a chill pill and stop spreading misinformation.

Edit: You may not be aware of the international differences in views on visual approaches. Requesting ILS is far from the "silly request" you seem to be trying to mock. This doesn't mean that ATC was wrong to make the decisions that they did, but it does mean it is a reasonable safety request to make. https://aviation.stackexchange.com/questions/47638/why-are-v...

if you are not willing to accept "no", you are not making a request, you are making a demand.

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