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https://www.flightaware.com/live/flight/QFA63/history/202501...

This is one of the more remote flights humanity operates. What even are the diversion points on this route, McMurdo airfield?

I'm not an Elon shrill but this seems as an ideal place for SpaceX to be re-entering things as they can choose with minimal damage to ecosystems.




I know you're not exactly serious, but to answer anyway: McMurdo isn't near this flight path, it's at New Zealand's longitude (so 2000 miles east of Australia) and much farther south. Perth would be the closest airport for almost all of that flight path.

(Your core point is correct, this trajectory is about as remote as SpaceX can possibly get, even if it's near a small number of flights. Let's not extend NIMBYism to space and ban SpaceX from everywhere.)


This is an interesting article about what is considered the most remote point on earth: https://www.theatlantic.com/magazine/archive/2024/11/point-n... A lot of satellite debris is targeted there but of course we cannot expect all space debris to be so controlled and in this case SpaceX went for a region that was quite remote.


But why does SpaceX need so much of that space? It's a massive ocean - drop the satellites somewhere else, or at a time there aren't airlines in the way.


Because small differences early in the trajectory result in large differences later on. Think of driving a trailer backwards and imagine you weren't allowed to do corrections after a certain point.


Most likely they don’t, but safety margins for experimental rockets need to be large.


I’m a bit surprised the Southern Indian Ocean wasn’t prioritized. That is even more remote.


The flight was over the Southern Indian Ocean?

https://www.flightaware.com/live/flight/QFA63/history/202501...


Duh, sorry. Got confused.

I don't think there are diversion points, you either keep going to destination or turn around. The A380 is rated for ETOPS-330, that's 5hr30min from a diversion airport.


Incase anyone is wondering about ETOPS-N

For example, if an aircraft is rated for ETOPS-180, it means that it is able to fly with full load and just one engine for three hours. [1]

Obviously in this case it 5hours 30 minutes on one engine at full load.

-- Slight edit: Unclear if with a 4 engine its rated with 2 functional or still 1 functional engine.

[1] https://en.wikipedia.org/wiki/ETOPS#Usage


I believe it's not just that it is able to fly with 1 engine. It's that the probability of a secondary engine failure in that time is below a certain threshold. Most twin engine planes can fly perfectly fine for basically any distance with an engine out, ETOPs provides confidence that the other one won't fail too.


Yes, for example the FAA requires a failure rate of better than 1 per 100,000 hours for ETOPS over 180 minutes.


do they test a failed engine or is it simulated? as in do AirBus and Boeing fly a plane intentionally fail an engine and then see what happens


Flying multi-engine aircraft with an engine shut down is a routine training and test maneuver, so these aircraft have all been flown a lot of hours with an engine out. The tricky thing about ETOPS is ensuring very high engine reliability (so that the probability of coincidentally having two engines fail on a flight is low) and avoiding failure modes that would affect both engines at once (one of the reasons for a lot of redundancy in electrical systems).

And while technically different rules, ETOPS in practice gets attached to other requirements for transoceanic flights, so ETOPS aircraft often have additional life rafts and other equipment.


There’s a bunch of regulations, but from looking through them quickly I think they start with a bunch of testing and analysis initially to show a predicted rate under the requirement, and afterwards they look at the real-world rate with a 12-month rolling average.


It is my understanding from a (no-longer-available) MIT OCW aircraft systems design video that these requirements are based on one engine failure on the aircraft, regardless of the number of engines on the aircraft.


ETOPS per se makes no sense for a 4 engine aircraft (the T in the acronym is "twin-engine".) Three- or four-engine aircraft have equivalent engine-out long-range operations ratings, though.


Apparently the acronym can now be read as the blander "ExTended OPerationS", or according to the ICAO all such flights can be referred to as EDTO (Extended Diversion Time Operations", which is less fun to say out loud and loses the joke definition "Engines Turn Or People Swim")


There is a runway (YWKS) on antarctica 'moderately' close to the point where the midpoint of the great circle for that flight is, I'm willing to bet it's used as a diversion point for ETOPS purposes for those flights. It couldn't handle airliners daily, but in an emergency (in summer at least) I bet it could be mobilized just fine.

edit: allegedly YWKS does have a regular A319 service from Australia.


A380 has 4 engines, so maybe it doees this with more than one ?


I think it means it can do it with 1, but the fact it has 4 gives it great redundancy.


I'm not sure. In the case of 4 engines, it may be 2 is how they certify it. Specifically I think the case where both engines on the same wing fail (as the worst case other that losing 3)


The rating is taking into consideration that it has 4 engines. The term is just confusing because it used to only apply to twin engine aircraft.


In practice do they normally fly that far between possible landing spots? My understanding is that they try to normally stay within 2 hours of a possible landing spot

does aircraft only operate engine as minimal as possible to save fuel or they burn more if they use fewer engine to having engine work extra because of its weight ?


Yes they’ll use more fuel than running on all engines. They always load the extra fuel that would be required for the maximum flight time with an engine out.

The extra fuel burn is due to the drag from pushing a non-working engine through the air, and from the rudder deflection to counteract the unequal thrust. It’s less of an issue on a four engine aircraft with a single engine out as they can increase thrust on the remaining engine on the side with the engine out.

Extra fuel burn is also required because a twin engine aircraft with an engine out can’t maintain the normal cruising altitude, and the higher you are the more efficient the engines are.

Thrust can’t be reduced much to save fuel because the speed margins at altitude are quite narrow - if they reduce thrust and therefore airspeed they’ll descend.


> It’s less of an issue on a four engine aircraft with a single engine out as they can increase thrust on the remaining engine on the side with the engine out.

Do they also decrease the opposite engine to help with this as well?


That's an option.

Aircraft with disabled flight controls have occasionally steered / maneuvered utilising variable engine thrust alone. A notable instance is UA 232 (1989), Denver Stapleton to Chicago O'Hare, which crashed on landing at Sioux City, Iowa. Despite a nearly completely disabled aircraft and a violent landing, there were 184 survivors of 296 souls, including the pilot Alfred Clair Haynes (he died in 2019, aged 87).

The aircraft, a DC-10, suffered an uncontained fan failure which severed all three hydraulic control systems, disabling virtually all flight control surfaces (elevators, ailerons, rudder), and the pilots (with assistance from a dead-heading pilot/instructor passenger) controlled both horizontal and vertical orientation using engine thrust alone.

I've heard and read numerous times that in simulations of the incident afterwards few or no pilots managed to land the plane. Haynes was an absolute master pilot.

<https://en.wikipedia.org/wiki/United_Airlines_Flight_232#Att...>

<https://en.wikipedia.org/wiki/Al_Haynes>


> The A380 is rated for ETOPS-330

I thought ETOPS is for 2 engine aircraft. Are there minimum diversionary requirements for 4 engine aircraft?


Yes that changed some time ago, it applies to 4 engine aircraft as well.

You are correct. Diversion points are Perth or Durban. Nowhere else.


It's incredible a 14 hour flight can run with that level of certainty!


>This is one of the more remote flights humanity operates. What even are the diversion points on this route, McMurdo airfield?

The acronym ETOPS is sometimes jokingly expanded to Engines Turn Or Passengers Swim... but, in this case, it is perhaps closer to reality than usual.

https://en.wikipedia.org/wiki/ETOPS


In this case the water's probably cold enough nobody would need to swim for long.


I used to geek out on this, another one from pre-covid was Santiago Chile to Sydney AUS, 2-3x a week. That looked like one _lonely_ flight.



> shrill

I suspect you may have meant to say shill instead.


Why is that anyone else's problem besides SpaceX's? Are they going to pay for it?


Why would Qantas have the implicit right to the airspace first? Space travel and air travel are both value-added human activities. I can't see why we would always prioritize air travel (particularly in very remote locations like this) over space travel.

Most flights will never be impacted this way.


You're kidding right? This is space debris. If a Qantas flight crashed into your neighborhood, you know who's responsible right?


It's not space debris, it's the deliberate disposal of the upper stage of the rocket precisely to prevent it from becoming space debris. The time and location of re-entry are planned and controlled. This is not going to crash into your neighborhood (except if you're neighborhood is in certain areas of China, where they they happily dump spent rocket stages on populated areas).


To be fair, I’m not sure happily describes it. Indifferently? ‘We warned them and they didn’t move, so f them?’ Ly?


Are international waters in the southern Indian ocean Qantas' neighborhood?


Would you ask the same question if it were Long March rocket debris falling into the Atlantic with very short notices from China?


It's not the waters that's important here. It's the debris passing through the flight path.


Another way of phrasing the situation is that Quantas _very inconveniently_ chose to put their flight path straight through the projected trajectory of rocket debris.


Qantas doesn't own the flight path either?


Oh common?! Do you own the travel path when driving down the highway? No you don't but there are agreed upon and codified rules on right of way that protect your right to safe passage or navigation. Similar convention applies to air space and air travel, look up Annex 2: Rules of the Air by ICAO which outlines right of way principles for air travel


What does it say has right of way between a rocket stage, that cannot be steered, and aircraft, that can?


The FAA confirmed that debris fell outside designated areas, temporarily disrupting air traffic and causing several aircraft to divert or delay flights.

You can read more here and other news sources

https://www.foxbusiness.com/technology/spacexs-starship-grou...


> between a rocket stage, that cannot be steered

This is just trash. Debris as they call it.

If drive in front of you on a highway and throw some "debris" out of the window, will you enjoy it ?


Will I enjoy it? What's that got to do with anything?

That’s because I own my back yard. Qantas doesn’t own a 3D space in the sky.

A flight is using a very narrow path, the rocket debris is "claiming" a huge unavoidable areas over probably a relatively long period of time.

I wonder what the math is on the plane actually getting hit if it took it's normal route.


Something with a lot of significant decimal places that are mostly zeroes.

Unfortunately "got hit by space debris in designated NOTAM area" looks bad in headlines.


> Space travel ... value-added human activities

Heavily debatable.

And you're equating to SpaceX dumping debris and trash in addition to their original flight path to a plane's flight path. Those are not equal things.


Why not? Both are an essential part of the operation.


Do you consider launching spy satellites "value added human activities"?


depends who's doing it. china, for instance, classifies everything they send up as "military" with the ITU to avoid disclosure. the US is a net positive in the world, so our satellites are too.


Curious which countries you think are net positives. China?


china is a tougher one. she has been strongly positive in the past, as well as strongly negative; now she is much closer to negative. net all that i'd say negative overall.

> What even are the diversion points...

perhaps Diego Garcia

https://en.wikipedia.org/wiki/Diego_Garcia


I can't imagine that much ... nothing out there.


[flagged]


> Is this [SpaceX flight] for the benefit of humanity?

Yes. Much more so than that one weird flight that's "merely profitable for a single company".

> Do we all get a profit sharing check at some point?

Yes, in the form of more space sector jobs, more jobs and economic benefits that come from more kinds of useful stuff being launched to space more often, and eventually - hopefully - more jobs in space and economic benefits coming from that.


That really downplays the amount of collaboration needed to make a flight like this happen. The airplane was designed and built by tons of people in lots of different counties, building on a century of aviation industry knowledge. The amount of work and experience that goes into making a machine that can safely be 5+ hours from a landing site is enormous.


None of that means you're automatically operating it on behalf of humanity or even to the benefit of all humanity.


“This is one of the more remote flights humanity operates.” doesn’t mean that either, so what’s your point?




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