First flight of the Airbus A321XLR with up to 4700 NM range | Hacker News Reader

First flight of the Airbus A321XLR with up to 4700 NM range

airbus.com

113 pointskken167 comments

Couldn't figure out what the big deal is from the link, so after some further research, this is what's going on. The A321XLR is a smaller more efficient plane that will make long range but less frequently travelled routes profitable without the need for transfers on bigger planes.

4700nm would allows flights from say London to 49 states and all of Canada (as well as the middle east and most of Africa etc)

http://www.gcmap.com/mapui?R=4700nm+%40lhr&MS=wls&MP=o&DU=mi

That said there's already a 4000nm range, and narrow body flights of that distance aren't that common.

> 4700nm would allows flights from say London to 49 states and all of Canada (as well as the middle east and most of Africa etc)

Isn't that already possible? An ancient 747 can do up to 5300.

Yes, but a 747 wide-body is a lot larger and hence needs a hub-and-spoke route network to fill these giant planes at a hub to make the flight viable economically. The narrow-body A321 can be filled with ~200 passengers (compared to almost 500 pax capacity for a 747-800) at many smaller airports, making long-distance point-to-point routes from these airports viable.

FWIW long-range widebodies are not necessarily jumbos, a 787-9 seats under 300, and an A350-900ULR has 315 passengers.

Assuming the XLR can be configured like a regular 321neo, it can reach 244 passengers in single-class configuration, and 200 in dual-class.

A 787-9 seats "just" 300 because typically 30 seats are 'premium business' where your seat becomes a bed and you have a partition - basically first class but less service and a bit less cushy. 30 are business. 30 are premium cattle class. 200 are cattle class.

https://thepointsguy.com/guide/tour-aa-boeing-787-9-dreamlin...

A 787-9 can seat 400 in single-class configuration. It has more than twice the maximum take off weight of the A321XLR. It's a significantly larger plane.

(the A350 is even larger)

That's a widebody, it's a completely different capability (and price, or purchase and operation) than the narrowbody A320 family. Long-range widebodies can fly more than 9000nm.

The issue is that a 747 is too big to fly from, say, London to St Louis profitably.

This is a single aisle, small aircraft. It is a big unlock for more point to point, small market to big market flights (and even small market to small market flights).

Flights like NY-FLR without having to transit somewhere in the EU will become an option, at least over the summer, might become an option (if FLR even has customs/immigration).

Are labor costs a significant percentage of the cost to run a route? A smaller airplane with less passengers will need less flight attendants but I'm guessing it'll need nearly the same number of pilots, co-pilots, and relief pilots. Given the ever-worsening pilot shortage, simple staff availability might be an issue regardless of labor costs.

"767-300ER consumes 1,600 gallons of fuel for each hour in flight" according to one link, to give you some back-of-envelope math.

Looks like in the US, Jet A costs roughly $4/gal (I'm sure airlines pay less, due to volume and such) but that means the plane is burning $6500/hr in fuel.

Very rough guesses on labor: figure the two pilots are making $100k/year, that's $100-200/hour just for them. Cabin crew I'd guess are 50k/year, google says 7 of them, so that's $350-700/hour there (figures are doubled because I seem to recall the true cost of an employee is usually twice their salary?)

So very very roughly, fuel costs are 10x labor costs

Commercial pilots flying international routes should be making way more than $100k/year.

> Very rough guesses on labor: figure the two pilots are making $100k/year

Fuel costs still outweigh labour, but a captain on a 767 makes more than double that (~$220,000-$250,000 USD or thereabouts). A first officer would be looking at $120,000ish, I think?

I used the average airline pilot salary according to glassdoor. I doubled all the labor costs to account for non-wage expenses.

I'm sorry that wasn't good enough for you in a comment where I repeatedly qualified things as "back of the envelope" and "very rough" and so on, and made it clear I picked one particular model out of the blue.

...and the difference between fuel and labor was an order of magnitude, which more than answered the parent commenter.

Also, pilot seniority / pay varies with the route and schedule, not airplane model.

> I'm sorry that wasn't good enough for you in a comment where I repeatedly qualified things as "back of the envelope" and "very rough" and so on, and made it clear I picked one particular model out of the blue.

Dude, I was just adding information for the unaware reading this thread, you can unnail yourself from that cross. It wasn’t an attack.

> Also, pilot seniority / pay varies with the route and schedule, not airplane model.

It varies by seniority and model they’re checked out on. Model they are qualified on determines the routes they can bid on - because you recertify every 6 months in simulator on your model, it’s not really possible to maintain a bunch of different active certifications and fly routes with different models routinely, so your model determines your pay. Source: close family member has been a commercial airline pilot for decades and has been actively involved in union negotiations.

Is this a recent development where people take a reply to by-default be an argument rather than sometimes just adding to discussion? I've seen it a few times on HN in the last year.

No, it's been that way since Eternal September

Plus the cost of the airplane (8x for A350?) divided by its lifetime in hours

the big cost reduction is engines. a jet engine is the most expensive part of a plane, so halving the number of engines dramatically reduces the plane cost and maintenance cost.

Fuel is bigger. A 4-engine 747 is thirsty.

It's a big reason why the A380 fizzled out as a program. The era of the very large plane is pretty much over, as long as it has more than two engines.

---

Labor is not a particularly large cost, especially if you are in a country that has access to cheaper labor.

Pilots get paid less for flying smaller planes.

Florentine here. We already have a JFK-PSA with Delta in the summer season operated with A330. FLR has a very short runway, so very few aircraft are allowed to landing there. A320neo is one of them, so I suppose also A321.

I don't think they've flown that flight in a lot of years....

But a 747 or similarly large aircraft carries 400+ passengers and is not economically viable at 180-200 passengers like the A321.

Smaller but longer range aircraft (like the 787) have enabled airlines to fly direct on long routes with lower demand (instead of having to make a stop, usually at the airline's hub eg. Dubai for Emirates)

A modern twinjet has much better fuel specifics than an ancient, 4-engine 747.

The thing is that a narrow-body like this can land at a much broader ranger of airports than a wide-body like a 747, which forces you to run people from regional airports to a hub and then transfer onto the wide-body. So this gives you the ability to run far more point-to-point routes with a couple of hundred passengers, with less of the scheduling complexities of point-hub-hub-point connections.

In larger planes it's an easy range, yes. But it's not currently possible in any other commercial passenger plane this small.

Even a slug has a 4000nm (4um) flight range.

Nautical miles (unfortunately) 7408 km (kilometers).

Oh, that is only 4,759,624 fathoms. Got it.

A nautical mile is one minute (60th of a degree) of latitude, in other words defined with the same technique as the meter originally was.

These days it's just exactly 1852 meters. Since the Earth is not perfectly spherical the historical definition is ambiguous and until relatively recently the distance was different depending on jurisdictions.

The same applies to the meter.

The point is the unit makes back of envelope calculations easy for coordinates on Earth, which used to be important to sailors and airplane crews with limited CPU time allotted for math ops.

So this plane can run for 4700 minutes? ...

So long as you understand "minute" to be a measure of distance, not time.

Interestingly, "minute" as a unit of distance derives from it's usage as the small (or minutus) division of the day (the larger one being the hour). The hour (and thus the minute) were defined by how far the stars traveled overhead, their speed thought to be constant for any given celestial latitude. So dividing that speed by distance does bring us back to a unit of time, as expected. But the Earth is divided in 360 degrees yet the day by 24 hours, so 1 minute of latitude (at the Equator) is not the distance that a star travels in 1 minute of time. Let's see... 360/24 = 90/6 = 15... 4700/15 >~ 4500/15 = 300. So the A321XLR can travel just a bit further than the distance that a star over the equator would pass over the surface of the Earth in just over 300 minutes or just a bit over 5 hours.

And just as an interesting aside, you can now understand why the word for the second smaller division of the hour is called what it is.

and then some

> 4700nm would allows flights from say London to 49 states

The official website for this aircraft doesn't seem to suggest that, for example all of California is outside its range graphic:

https://aircraft.airbus.com/en/aircraft/a320/a321xlr

I'm not able to use that gcmap website linked.

Flying from London to the west coast goes against the jet stream, so range is shortened by flying into the wind. Transatlantic routes that are currently using narrowbodies will sometimes have to divert for a fuel stop when the jet stream is particularly strong.

Isn't the latter what they want to change?

For me it's very interesting to get direct flights to locations that don't have enough traffic for a widebody.

There are narrowbodies across the Atlantic though, the question is how low can a company like ryanair price say a Dublin -> Manchester NH flight to ensure they can fill a flight connecting New England to Ireland.

But they don't operate that type of route with existing planes, not sure how the extra range would help.

This will open up cities that are further and bigger than Manchester NH (Wikipedia gives me a population of 115k).

I was thinking Manchester or similar because Boston would be too expensive to land at, but still serves the general area -- that's Ryanair's M.O.

It could open up a new industry specifically for this purpose. Right now for narrowbodies all transatlantic routes are pretty marginal in terms of range. There are some but only on very specific routes, which doesn't scale (you don't buy airliners for just one route because you'll have a huge problem if you need to change it).

And Ryanair is an Irish airline but Ireland is far from its main market these days. For the rest of Europe it's already a lot harder to reach with their aircraft.

There are a few lowcost airlines already targeting this market, like "Level" in Spain. They had to scale down long-haul destinations significantly since Corona and I could imagine smaller capable aircraft could pick these back up.

I live in a smaller city in Europe that could really benefit from such destinations.

But a ryanair, or ryanair style system, could fly from a large part of the US (certainly the east coast) to a large part of Europe already without the XLR A321s. What new routes does it really open compared with the A321LR?

First read it as 4700 nano-meters, and really couldn't figure out what the big deal was.

Right? Clearly they are talking about torque, which makes it more impressive, although I'm not sure what torque exactly.

distance not torque, Nautical Miles (NM)

My sarcasm meter is all over the place :/

I'm not sure what a range of 4700 Joules mean either!

Torque would be N⋅m or N m, not nm.

Fantastic Voyage?

Are you Android Auto in Canada? I've had it tell me numerous times that I'd be home at 8:04 micro-meters.

For those of us used to Freedom units:

4700 nautical mile (NM) = 95,192 football fields

1.852e+12 nm in a nm

and 1.852 km in a nm

therefore 1.852e+12 * 1.852 km = 1 nm

i.e. 1 nm = 22927.4921 astronomical units

Talk about extra long range!

It'll enable point to point flights for many airport pairs which IMHO is the future of air travel. Connecting flight are too slow, too unreliable and too expensive to run.

Low cost airlines will use it to eat the more established players' lunch in longer haul flights (cross country, international).

So far no airline has managed to crack the low-cost transatlantic nut, usually they try it and collapse in a few years. I don't think anything is significantly changing in that regard.

What would need to change?

Honestly, probably the business model itself.

---

LCCs thrive on extremely efficient utilization; they basically match planes and crews to maximize as much time as possible in the air for everybody and as little rest as legally allowed. This is easy to do if you are a short haul carrier with lots of short flights that could reasonably slot around.

Transatlantic flights are 6+ hours. This makes things more difficult in terms of scheduling, particularly since these LCCs will probably only have a short-haul network to use up the rest of the time on one side of the pond. The longer a crew is in the air, the longer their required rest period is, and that decreases utilization.

---

Most of the money on transoceanic journeys is also premium journeys (e.g. first and business.) It's how British Airways books $1B in revenue annually on JFK-LHR alone. But LCCs don't really target this group of people, and the budget-conscious are a fickle market for such long journeys. They also can't easily attract this more expensive customer unless they stump up the cash to provide equivalent amenities, but then that blurs the line between legacy and low cost carrier.

The big deal is that two engine aircraft are now covering the routes that were once only practical (or legal, under ETOPS[0]) with three or four engine planes. This makes them more desirable and helps carriers phase out the larger planes they still have -- none of which are being manufactured anymore.

[0] https://en.wikipedia.org/wiki/ETOPS

Not that I'm in the market, but this page has the sales pitch stuff on it, and it's pretty interesting reading:

https://aircraft.airbus.com/en/aircraft/a320/a321xlr

According to a few other sites they appear to cost between 130 and 140 million. Looks like they've sold some already too.

"London" https://imgur.com/a/RSVdLjM

After Brexit it was much cheaper to just move London into the middle of France, apparently.

Sheesh, and I thought the commute from Stansted to the city was rough.

meh, National Express takes you to Golders Green where you have the northern line.

On the maps of where it can fly, are they using some super advanced model to give the 'odd' shapes (for example the delhi one, which is totally not just a circle projected onto the globe and then reprojected onto a map)?

Or is it just an artist impression who was given a list of cities and has drawn a dotted line around them?

I wondered from your question whether it was accounting for ETOPS requirements but it doesn't look like it.

> Or is it just an artist impression who was given a list of cities and has drawn a dotted line around them?

Seems to be the latter, some cities aren't even in the right place (London is set in french Brittany, Rome seems to be adrift in the Thyrrenian sea).

Rather purchase an EUV machine for that price.

Why would an airliner purchase and EUV machine? Unless you know something I don’t. Delta 4nm process node coming to a chip near you.

Funnily of all airline companies out there you picked Delta which is not to be confused with Delta Electronics (https://www.deltaww.com/), so a Delta 4nm node is not that far-fetched.

One EUV machine does not a fab make.

Yes, TSMC are apparantly investing $12 billion [1] to build and maintain their new Arizona fab over ~10 years. So yeah, costs a bit more than the $200m EUV machine!

1. https://www.eenewseurope.com/en/tsmc-confirms-5nm-fab-in-us/

But that can only do 4nm, so the airbus is like 1000x better

I have no desire to cross the Atlantic in a narrow-body. It's inhumane to have that many people locked together in a thin metal tube for that long.

The cabin is a bit wider than standard a320. They advertise 18" wide seats. If they are 32" apart that's ok. It can even fit lie flat business class seats. And if it means flying direct instead of changing planes in a busy overcrowded airport and having to lose time waiting and queuing (and "saving the planet") that's pretty appealing

> And if it means flying direct instead of changing planes in a busy overcrowded airport and having to lose time waiting and queuing (and "saving the planet") that's pretty appealing

That is the most important thing imo. A 6 or 7 hour flight to your destination is so much better that the same length to Frankfurt or wherever and then waiting and taking another 1-2 hour flight somewhere. Most of the pain with flying, except maybe of ultra long-haul, is what goes on before take off and after landing. If you only have to go though that once, it's a big deal.

Plus, I dont see any material difference in comfort between modern wide and narrow body, other than your less likely to be stuck in a middle seat on a narrow plane and they board faster.

The A321 is not wider than an A320. The A320 family[1] comes in a variety of sizes and configurations to support different profiles, but they are all variations in length, fuel capacity and MTOW.

Making a plane longer is relatively straightforward, just insert additional sections before or after the wings. Making a plane wider you may as well design a whole new aeroplane.

[1] https://en.wikipedia.org/wiki/Airbus_A320_family#Specificati...

I said "cabin is a bit wider" not the plane itself. I was under the impression that with neo they made the isolation on the walls of the cabin a bit thinner (2 inches?) gaining more room in the cabin while keeping the outside shape the same but I can't find anything about it anymore

EDIT: oh yeah found it: https://tqpr.com/airbus-new-single-aisle-airspace-cabin-ente...

> The new Airspace features include: slimmer sidewall panels for extra personal space at shoulder level

or https://www.ainonline.com/aviation-news/air-transport/2017-0...

> The Airspace package includes new sidewalls that provide one additional inch of shoulder-height cabin width

I'd take 8 hours in a A321 with Jet Blue's layout (in mint or economy) than any wide body from AA or United.

As a tall person, I don't think there really is any significant difference. The seat pitch in economy on most jetblue flights is 32" (per seatguru), which is generally the same as united/aa on transcontinental. Yes there are UA/AA/etc layouts with 31, as there are jetblue with 34". The bottom line, is that if you don't fit in these smaller seats, paying the upgrade fee on a crappy airline/ticket generally gets one more space than flying a more premium airline. But the difference is frequently nullified (cross airline) simply by selecting a different date/flight with an alternative plane/seat layout.

(and the widths all tend to be ~17.5" or so)

It's not all about seat pitch; on an A380 you can get up and walk around for a hundred meters or so, on a small plane you are basically stuck in your seat or the bathroom.

Not to mention the bars and lounges in business & first class.

https://onemileatatime.com/guides/airplane-bars-lounges/

A380 is mostly history. Many airlines abandoned them during Covid and I have not heard of any revivals.

Emirates have them going full steam ahead again (they have 120 of them). I hear the 9:00pm flying from my city to Dubai every night. Qantas have re-introduced them - I think four at least are back in service, three are undergoing cabin refits and by mid next year they will have 10 back in service (they are retiring 2 of the 12 they had).

Emirates for sure, but they are an exception. No other operator uses them at the same scale.

While I like the A380, I must say I am glad having avoided the Gulf Airlines so far. One time it was close that I booked family trip with Ethiad, but then my wife said they are supressing women, she will stay at home. Of course ethical arguments could be probably applied to any airline in Europe, flying with oil from the Middle East and now from Russia. And of course for all cars, but luckily I don't drive.

Narrowbodies have much less people in them. Already they're enabling much cheaper business class seats across the Atlantic.

To me international narrowbody travel is all win.

Airlines have been doing this with 757s for quite some time. This is the best spiritual successor to the 757, which is going to have to be retired in a lot of fleets sooner rather than later.

The layout makes much more of a difference than the number of aisles - I am fine with a 757 but have hated my economy experience in a 9-abreast 787.

I've flown more than I care to even think about, the carbon footprint of my life is about as ugly as it gets. That said, I do have a bit of experience to draw on and my current favorite is a narrowbody:

https://en.wikipedia.org/wiki/Airbus_A220

Originally designed by Bombardier, every flight with it that I've made so far (~10) has been an extremely nice experience, especially when compared to other planes on the same routes. The only plane that I would prefer is the 747 but that's pretty much gone on passenger routes now and those two planes would not be found on the same routes anyway. So a long flight in a narrow body is definitely not something that I would run away from.

Yes, I will pay extra if it’s an option to fly with their planes.

I've only flown on 747-400s with BA and Qantas, and I've found them to be terribly loud. I've heard the 747-8s were a little quieter, but would you really say that would be better than a 787, A350, or A380?

I too have heard that the A220 is a fantastic plane. I'm looking forward to Qantas flying them.

The A220 emits very strange engine noises in some phases of the flight. Personally I must say I find them very unpleasant. My wild guess it's the gear fan.

It doesn't help to know that their have quite some engine problems. Although objectively I doubt the noises and engine failures are related.

You mean the "whale song"? It's just a quirk of the Pratt and Whitney PW1000G series at low power settings. The same engine family is fitted to new Airbus A320neos and makes the same sound. Examples:

https://youtu.be/Eeq4rYQUozY

Ah, I didn't know it's called whale song, but yes that's what I mean. Low power setting might be correct, I think you hear that typically in approach phase. I have been flying with many types planes from Vickers propeller, Caravelle, 727, L-1011, 717 and its predecessors to 747-8, A350, Dreamliner, but I never remember hearing a sound making me feel so uncomfortable. Despite the fact that the old ones were uncomfortably loud. After over 40 years of flying I nearly thought, now I can understand people suffering from flying anxiety.

Don't remember hearing it on a A320 neo, but I guess they come with 2 engine options?

I've never flown an A380 so I can't really comment on that and yes, I much prefer the 747 on longer routes over 787, A350 vs 747 would be more or less a wash, noise is mostly a function of where you're sitting in the plane so you have a bit of control over that (and these days: very good noise cancelling headphones).

What's the difference? Like how does the width of the body have any impact on me? I'm asleep in my seat the whole time either way. I'm not pacing side to side!

Not only is it wider, but it's taller. At least for me, all else being equal, widebodies feel far less cramped just because there is much more room inside. It's a bigger difference than a regional jet versus a mainline narrowbody.

Are you flying standing up?

I said they feel far less cramped.

Ryanair is going to pounce on this idea

They already tried to implement it years ago, or at-least Michael O'Leary claims so.

Imagine how much GHG emissions they could reduce if authorities let them innovate on pods or bunk beds.

Heck just give me bean bag or even a yoga mat and I’ll be happy.

When you have long flights it's nice to have space to walk around the cabin, go to the back and have a drink etc.

Also I feel like even if you are sitting the whole time, there's a difference in perception between sitting in a small confined space vs sitting in a space that is larger.

I've done JFK-OPO on TAP on a 321LR a few times; it's 2-2 staggered 1-1 in Business and quite nice. (https://thepointsguy.com/reviews/tap-air-portugal-a321lr-bus...)

That doesn't look bad at all. I probably just hate A320s and 737s from too many easyJet and Ryanair flights where there wasn't even the option of a good seat.

This is a frequent argument I see, but I don't see much substance in it. I've flown with both narrow and wide body, and the most critical dimension is leg room and shoulder width. And I did not find any particular wide body advantage with the sardine-packed 777 comparing to a regular A320, or especially A321, which I have flown in many times. Comparing to a 737, maybe some, but the 737 is an age old design, it is known for not being too spacious. It's not a A321 contender.

I expect they'll have different seat configurations for longer range planes. 3-4hrs is fine but I can't see how anyone would want to fly 8 hours with the legroom common in Ryanair or Spirit.

I mean, people have been trying to make transatlantic low-cost happen for a while now. not successfully, but people have tried.

> 8 hours with the legroom common in Ryanair or Spirit

At this point I’d rather just stand like in a bus

Jet Blue is doing narrowbody JFK to London and I have to say the seat isn't the problem. One aisle is.

It was fine but even as a JetBlue fan, I'm not in a rush to get back on the narrrow body for transatlantic.

What was wrong with the single aisle?

1 person can block the aisle completely.

Every person that goes to the bathroom in front of you will pass you and the plane is smaller so the commotion is noticeable.

Service blocks the bathroom for a long time because of less bathrooms.

Just booked a cautionary flight on new airline called Breeze, nonstop LAX > WHITE Plains, bypassing the major NY airports and impressive bridge tolls in an A-221 configured with 5 seat rows where the middle seat is innovatively wider than the rest, at a very competitive coach fare even after the upsells. A first passage with a new airline is always a leap of faith but my first translantic flight back in 1971 was a venerable, loud and smoky 707, so the long-haul single aisle flight doesn't faze me like it does the younger travellers.

Still beats swimming. Besides if it means not having to transfer to a connecting flight I'll take it. Airports are hell.

I was once on a United 757 from Chicago to Dublin. It wasn't my favourite flight.

I’ve flown 7 hours on a (commercial) all business class A320 and it was pretty nice. Seat config is going to be everything

I don't see what impact the aircraft being narrow-body has on travel comfort. It's all about seat pitch IMO, and that can be bad also in a wide-body.

After a huge investment in the hub-and-spoke uber-plane (the A380), this plane feels like a hopeful departure, especially for people that travel to the less popular ends of the earth that have to take 3 hops to get there.

https://www.flightradar24.com/data/aircraft/f-wxlr/#2c40a673

These could become quite popular for tourist charter flights as they should have a decent range even when packed to max capacity. Plenty of long-haul tourist flights from Europe to Africa, South-East Asia and Caribbean could use something like this. Not the most comfortable way of travel perhaps, but people won't care if the price is right.

Looks like it uses PW1000G which in its most efficient version is 12:1 bypass https://en.wikipedia.org/wiki/Pratt_%26_Whitney_PW1000G#Ultr...

The Trent 1000 on 787 is 10:1.

Fuel capacity 40,000 liters of fuel. At a range of 8,700 km, that'd be 0.217km/l or .511mi/g.

An Airbus A350-LM, a widebody/higher-capacity plane that can go 15,000 km, has 141,000 liters of fuel. That'd be 0.106km/l, or .249mi/g.

I suspect these figures are a bit off, as I doubt "range" == "all fuel burned". But it's at least somewhat representative.

Normally for airliners you compare fuel burn per distance per passenger.

At 200 passengers you'd get 2.3 l per 100km per passenger (100 miles per gallon per passenger), in line with a small sedan car.

Personally I think it's useful to use scales & dimensions people already know & grasp. I'm having a hard time combining all the factors you're smooshing together. I haven't figured out- 2.3 what per 100km per passenger? I haven't run any numbers to run that have gotten me 2.3 anythings.

Using my figure, if you want to get per-passenger, if we say it seats 200, we can multiply .217km/l by (1 plane/200 persons) and get 43.4 km/l / person, or, 102mpg/p, which I think most people will understand reasonably intuitively, compared to what they already know. This is indeed a rather impressive claim. It makes me wonder why they don't just call this thing the 100mpg plane, if true.

> Personally I think it's useful to use scales & dimensions people already know & grasp.

To the best of my knowledge, most of the world reports transport efficiency in l/100km. And the poster even nicely included the US-centric mpg value for people in not-most-of-the-world.

Some (most?) regions compare fuel efficiency by how much fuel in liters is needed to travel 100km.

English speaking countries (or at least most of them) usually do it the other way around and compare the distance one can travel by fuel unit.

distance per fuel quantity ~~ efficiency

fuel quantity per distance ~~ inefficiency or cost

The US and UK are probably the only English-speaking countries that measure efficiency in miles per gallon (and not even the same gallon). Everywhere else uses litres per 100 km. I believe my car (2003 VW Jetta TDI diesel) gets about 4.5 L/100 km, which is quite good compared to a typical truck that gets 15+ L/100 km.

Australia and New Zealand only use L/100km, so it's not a language thing.

You weren’t able to divide 1 by 43.4 and multiply by 100 to get 2.3L per 100km?

I flew from Ohio to Melbourne back in ~2001. It was CMH-DEN-LAX-MEL. The leg from DEN to LAX was a 747 and there were probably 30 passengers in the entire plane. I was near the back of the plane and it gave me an entirely new perspective of just how much they bend and twist in flight. You could see the walls above the wings sort of bow in when lifting off.

Probably tied with hot air balloons for least efficient transport I've ever taken.

(For the leg from LAX to MEL i had the aisle seat beside the shitter galley in the back. 14 hours of people fanning their farts in my face.)

You should see what a big plane does fully laden.

The fuselage and wing of a cargo jet in turbulence basically "banana" in perpendicular planes.

I flew on a 757 from ORD to ROC years ago as the only passenger on the plane. The flight attendant just came and sat down next to me to do the safety briefing, told me she was sorry but no refreshment service, and then went up front. I didn't see another soul again until we were getting ready to land. That was a very eerie two hours.

I am not able to verify the accuracy of your calculations, but for comparison, Delta circa 2018 marketed how its entire fleet (flying at a pretty high capacity factor) averaged ~44 passenger miles per gallon.

I don’t know how air freight is factored into fuel efficiency calculations, but it has become an increasing part of passenger airlines’ business models in the past decade, too.

(Source: I spent way too much time keeping tabs on Delta as a top level frequent flier)

First I considered that 2.3l/100km is pretty great. But when actually scaling it to full car with 4 persons in it doesn't feel that special anymore about 9.1 l/100km. Which really isn't anything to write home about even in larger sedans.

If fuel economy is your goal, you can take a glider.

A skilled glider pilot can go (slowly) as far as they like with no fuel. The typical limit is when you get tired and need to sleep (gliding can't yet be done well by a computer, because it takes quite some skill to find the necessary thermals and wind currents).

There are also terrain and weather conditions.

Typically it is very hard to glide at night since a large part of gliding is the air movement caused by local and regional thermal differences.

Ardupilot (or one of its offshoots, I can't recall exactly) does have a lift detecting autopilot in beta. I don't know how it works with a specific route, but it seems to lock in thermals pretty well.

Now this is something I'd like to see. A permanent glider, in the sky for years on end. Obviously with humans onboard you'd have to resupply it with food and water.

But with a computer - train ML on human pilot behaviours? - it could stay there for quite some time.

Well, yes, but this doesn't drive on a road at 130km/h, it files through the sky at close to speed of sound

As long as you fill your car with 4 people, then yes it pollutes less.

Even that is only a fair comparison when comparing specific routes, as an airliner has the significant penalty of having to carry aloft its own fuel, and therefore becomes less fuel efficient on longer routes.

This doesnt make sense. I divided range by fuel capacity. There's no longer range possible.

Right, but the max range for an airliner is the distance at which its least fuel efficient, as it has to carry its max fuel load. Shorter routes will be much more efficient due to the lower fuel loading.

> At 200 passengers

Unfortunately, most planes fly far from their maximum capacity (even though most passengers are in fact flying in overcrowded planes).

Wonder how emissions/seat/km on representative routes differs from the larger planes?

Given that landing and takeoff is particularly bad for emissions if you're avoiding a change of planes I guess that might be a win ? Not as big a win as not flying but better ...

Given that the first example they give is NYC-LON it's a question that interests me.

the issue with big planes is that they're more efficient if you fill them up.

with 747 or 380 sized planes that was always a tenuous proposition at best. if it's not full it's still burning the fuel to lug its heavy big self around.

I find the other trade off (against the extra fuel consumption from each takeoff and climb) interesting. Additional fuel is consumed to carry the weight of the additional fuel required for a longer range (and so that is recursive). For example, under the Weight - Flight Distance heading of the Fuel Economy in Aircraft Wikipedia page, it notes that for trips above 3000 NM, it is more efficient for a 777-300 to make a stop for refuelling.

https://en.m.wikipedia.org/wiki/Fuel_economy_in_aircraft

4700*10^-9 meters seems like an extraordinarily small range for an airplane.

NM = nautical miles or what?

The main alternative I can think of is nanometers, which they probably wouldn't write an article to brag about. :)

Probably not Newton-Meters either. That's a lot of torque.

Yep, most airplane things are measured in nautical miles.

Stuck in the past of nautical miles and knots for distance and speed. And feet for height. Not that nautical miles don't make sense for navigation on maps.

Uh huh... feet is more useful for aviation than meters. 1,000ft is a comfortable vertical separation between planes and it's a nice round number instead of ~300m.

As for nautical miles and knots, one nautical mile is equal to one minute of latitude making for easier navigation when you're traveling over significant distances of the planet.

I'd hardly call it stuck in the past but rather the right units for the application at hand.

So by that logic we should mix metric and imperial whenever it rounds to a nice number. Pretty awful argument.

1. No one is mixing metric and imperial here. All planes use knots, nautical miles, and feet. No one is measuring altitude in meters in one location and then feet in another.

2. I guess we should just use metric for every application even when it doesn't make sense to do so then.

If you want to measure distance travelled over the earth you want nms since the earth is a sphere and you don’t want your route length to be longer when you’re at higher altitudes

If you’re measuring distance in nms you want knots as they’re nms/hour

We use kms for other things though- like weather minima, runway length - things on (or close to) the surface. Eg I need either 5km or 8km forward visibility to enter some controlled airspace.

Ft for height is less functionally defined though- that’s just the way it is because it’s the way it’s always been. Not much gain in changing it though

Correct, as other people have noted.

Nautical miles are used for shipping and air travel since the length of a nautical mile is derived from the size of the earth. A nautical mile is 1/60 of one degree of latitude.

Is it going to use https://en.wikipedia.org/wiki/Aviation_biofuel ?

Sadly I wasn't able to watch it lift off. I enjoy watching the Airbus models, esp. the Airbus Beluga XL over Hamburg, Germany.

Seen one for the first time in flight in RL when being to Hamburg last month. Was amazed!

Why isn't there a flight between Buenos Aires and cape town? Who is planning this routes?

As nearly all airplane are now twin jet, you need to respect the ETOPS rating of your aircraft, which is the time the aircraft can fly with one engine down before landing. That's why the transatlantic or transpacific routes are not direct and go over small islands

The ones quoted are just examples. The airlines will decide the actual routes.

Got excited briefly cos I misread "first flight" as "fist fight"

/r/planeswitharms

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