Per the FlightRadar24 logs, it looks like only about 45min was wasted over Prestwick, not 2hrs. First approach was around 18:06, and they're breaking off to head for Edinburgh by about 18:51.

If there's considered to be a mistake here though, I'm guessing it's going to be spending too long before committing to the initial diversion.

Without knowing the weather they were seeing at the time, seems hard to say if they should have gone for a closer 2nd alternate than Manchester.

I don't think we know yet when min fuel was declared. At that point, they will be resequenced. Then we need to know when mayday fuel was declared. It sounds pretty odd, like perhaps there were multiple simultaneous situations and the crew did not have adequate information.

Assuming it wasn't just luck, it seems impressive they managed to maximize their (landing attempts/fuel reserves) ratio like that.

It is a requirement [1] to land with 45 minutes of fuel remaining, if the pilots go under that, it is considered an incident. As soon as estimated landing fuel goes under the limit, the flight needs to declare an emergency (as was done in this case).

[1]: https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F... is the US rule, EASA has a similar rule.

Exactly. This will have a lot of consequences.

They got within a hair of crashing, there is nothing impressive about this. 30 minutes, ok, you still get written up but this is cutting it way too fine.

> this is cutting it way too fine.

Either this is true, or this is why there’s a 45 minute reserve requirement. There were three failed landing attempts in two airports prior to the successful landing, and they spent almost as much time attempting to land as the scheduled flight took.

Seems like this was exactly the scenario it was designed for?

No, this is what should never happen. I wrote fuel estimation software for cargo 747's and the one thing I would have never ever wanted to read is that an airliner of the company I worked for had landed with too little fuel.

Right but this is an emergency… they didn’t plan to run out of fuel

Clearly, that's why it makes the news.

Are there ever situations where running into the reserve would be a good trade off?

This one. The reserve is there in the same way that a crash barrier is there on the highway. You really don't ever want to use it, but when you do use it and it ends well you treat it just as seriously as though you would treat a crash.

I would imagine 6 min fuel left was designed for something extreme. Maybe involving damage to aircraft limiting where it can land etc. Or extreme weather event such had high winds affecting all airports within 500 miles.

About 5 years ago before ATC recordings became mainstay on YouTube, there was an American pilot that declared an emergency at JFK and very firmly said "we are turning back and landing NOW. Get the aircraft OFF all runways".

He was low in fuel and also frustrated with Kennedy ATC because he declared "minimum fuel" earlier and was still getting vectored around. (I know "minimum fuel" is not an emergency and has a very precise meaning).

They must have been very close to running out. But it was a valuable lesson learned in speaking up before you get to that point.

I’m guessing that pilot had also been taught the lesson of Avianca 052, which crashed at JFK because the FO / captain did not explicitly declare a fuel emergency.

JFK ATC in particular has an enormous workload with many international flights, combined with direct, even conflictual at times, NY communication style. It puts the onus on the pilot for conveying the message to ATC, rather than ATC for extracting the message from the pilot.

You might be thinking of https://www.youtube.com/watch?v=-sQuHnrJu1I

For comparison, this is what can happen when the pilots are not that assertive https://en.wikipedia.org/wiki/Avianca_Flight_052

this was it, thanks for finding it. I didn't realize it happened 14 years ago

> But it was a valuable lesson learned in speaking up before you get to that point.

I'm not sure it was a lesson learned per-se because the captain was merely doing his job as fundamentally defined.

A captain has ultimate responsibility for the aircraft.

However there is a side question in relation to your post...

When you say "declared an emergency" in your post, the more interesting question would be whether it was actually formally declared by the captain (i.e. "MAYDAY") or whether the captain was merely "working with" ATC at a lower level, maybe "PAN" or maybe just informal "prioritised".

If the captain DID declare "MAYDAY" earlier in the timeframe then yes, Kennedy would have a lot to answer for if they were spending excessive time vectoring around.

But if the captain did not formally declare and then came back later and started bossing Kennedy around, that would be a different set of questions, focused on the captain.

The word Mayday is not required to declare an emergency. Pan pan still indicates an emergency. And neither phraseology is required as long as the intent is clear, see https://www.faa.gov/air_traffic/publications/atpubs/atc_html...

In fact, it doesn’t even need to be the pilots who declare an emergency https://hsi.arc.nasa.gov/flightcognition/Publications/non_EA...

> The word Mayday is not required to declare an emergency.

That may be so in the US.

But it is a bad habit to pick up.

Especially if you are an airline pilot and you frequently fly to destinations where English is not the first language.

Or indeed in US airspace where you frequently get international carriers flying in and out.

There is a reason why there is internationally agreed standard phraseology for radio communications.

Everyone learns MAYDAY/PAN and the associated expectations around it (e.g. radio silence etc. etc.)

Not everybody will be able to adequately follow along if you have a long drawn-out waffle discussion over the radio ... "we have a little problem" ... "do you want to declare?" ... "oh wait, standby ...." ...."oh, we're ok for now" ... "oh actually maybe this or that"... yada yada yada.

If its truly an emergency then cut the crap and use the standard phraseology and keep the communications terse.

In the US, we don't typically call Mayday/PanPan (despite it being both allowable and more correct). Pilots literally say "N777DS declaring an emergency. Engine out/Low fuel/Birdstrike". The effect is that all emergencies are Mayday.

someone further down found the incident [1] I was referring to. It was 14 years ago, not 5 as I had initially thought. Curious to hear your take on it. Pilot said "if you don't give me this runway, I'm going to declare an emergency..." which I don't think is the most helpful thing to say. But there were definitely many swiss-cheese holes lining up that day.

1. https://www.youtube.com/watch?v=-sQuHnrJu1I

Context: because of bad weather.

But I'm truly surprised (in a bad way) people on the ground couldn't solve the situation earlier. The plane was in an emergency situation for hours, wtf.

Also, the airport density in the UK is high, they should have been diverted since before the first attempt, as it has happened to me and thousands of flights every single day around the world.

The incident investigation will surely focus on exactly those things. But: just like shipping aviation is at the mercy of the weather and even though the rules (which are written in plenty of blood) try to anticipate all of the ways in which things go wrong there is a line beyond which you are at risk. I've had one triple go-around in my life and it soured me on flying for a long time afterwards because I have written software to compute the amount of fuel required for a flight and I know how thin the margins are once you fail that third time. I am not going to get ahead of the investigation and speculate but I can think of at least five ways in which this could have happened, and I'm mostly curious about whether the root cause is one of those five or something completely different. Note that until there is weight on the wheels you don't actually know how much fuel remains in the tanks, there always is some uncertainty, to the pilots it may well have looked as if the tanks were already empty while they were still flying the plane. Those people must have been extremely stressed out on that final attempt to land.

There must be measurements of the fuel tanks state, right?

There are but this is not as precise as you might think due to a lot of confounding factors. Even the best flow meters are only about 0.2% accurate, and I find that seriously impressive.

Armchair quarterbacking it, but it was human error. They should have diverted sooner and been more aware of the weather.

Edit: there might also be part of Ryanair culture that contributed, but that's speculation.

That's one conclusion. But don't rule out a lot of other things that may have been a factor, for instance, they may have had a batch of bad fuel, they may have had less fuel to start with than they thought they had (this happens, it shouldn't but it does happen), the fuel indicators may have been off (you only know for sure after touch down), there may have been a leak, an engine may have been burning more than it should have. There are probably many others that I can't think of of the top off my head but there are a lot of reasons why the margins are as large as they are.

Those are all possibilities, but

https://www.flightaware.com/live/flight/RYR3418/history/2025...

They had at least an extra hour of fuel, and they landed at the third airport they tried.

Yes, that's how it should be. Something went badly wrong here. The big question is what.

I read and agree with all those options being possible. Except the "they may have had a batch of bad fuel". How would that work in your thinking? I can imagine a bad batch of fuel leading to engine damage or flameout and many other things, but it is hard for me to imagine how a bad batch would lead to not enough fuel remaining in the tank.

If you have more water in the fuel than you think you do (there always is some due to condensation in the tanks) then you might be able to reach your destination but you'll be burning more 'fuel' than your original estimate would have you believe because there is less power per unit weight of (contaminated) fuel.

This is fairly common in GA and there are cases where it has happened in scheduled flights as well. That's why fuel sampling is common practice.

Interesting. That makes sense. Thank you for the explanation!

It's supposed to be an extremely low amount and the fuel pick-ups are placed such that it should never be a problem but there have been cases where water in the fuel caused problems, including at least one notorious crash where the cause was identified to be fuel contamination.