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December 14, 2017 6:50 AM   Subscribe

- Why Planes Don't Fly Faster [SLYT 11:32] "Nowadays American Airlines Flight 3 still leaves JFK daily at noon, but the difference is that today Flight 3 is scheduled to arrive at LAX at 3:27 p.m, 44 minutes later than in 1967." So what's going on?

Bonus
For everyone who's ever wondered just what is up when you can't get a flight leaving at the time you want, this should offer some answers (it's not just to make your life difficult):

- How Airlines Schedule Flights [SLYT 9:41]

- Previously
posted by Juso No Thankyou (47 comments total) 31 users marked this as a favorite
 
That’s a great video thanks for posting.
posted by Annika Cicada at 7:06 AM on December 14, 2017


One interesting thing they left out of "How Airlines Schedule Flights" is that Abu Dhabi airport. All those flights happen at local nighttime.

Why? This may not be obvious unless you've had to fly out of Las Vegas or Phoenix in the summertime during the day (and had your flight delayed or cancelled)

On really hot days, the air is much less dense, and it can prevent the airplane from being able to take off fully loaded, given speed and runway length constraints. Abu Dhabi, being in the middle of the equatorial desert, has this problem daily. So they run their flights at night, when the air is cooler and the safety margins are better.
posted by Xyanthilous P. Harrierstick at 7:14 AM on December 14, 2017 [36 favorites]


He sort of glosses over the "congestion" part, which is a shame because there's so much interesting work being done to streamline airspace operations. The FAA's NextGen push is all about safely reducing separation minima and allowing greater flexibility in route planning to deal with the congestion issue. There's still an impetus to reduce travel times even allowing for the physical speed limit mentioned; longer routings caused by antiquated approach and departure procedures, weather diversions, congestion-related holds, and a bunch of other things all cause extra time in the air and more fuel burned. New equippage and procedures allow aircraft to avoid a lot of these problems.
posted by backseatpilot at 7:16 AM on December 14, 2017 [3 favorites]


Also, planes fly slow because people don't like sonic booms. You can't go supersonic over land in the US. You could build a much better Concorde today and half the flight time from NY to LA if you could go supersonic.
posted by leotrotsky at 7:17 AM on December 14, 2017 [7 favorites]


Interesting, but riddled with crap - particularly when he talks about Turbojets and implies that's what power modern fighters. His stuff about Concorde misses the fact that BA were still making a hefty profit on theirs even after they returned to flight after the 2003 accident - it was Air France who were unable to fill their seats and hence pulled the plug. Faced with having to take on the full maintenance cost of the fleet by itself, BA pulled the plug on their Concorde flights as well.
posted by Nice Guy Mike at 7:34 AM on December 14, 2017 [12 favorites]


I'm not keen on the summary of "Time is the enemy of the privileged few, cost is the enemy of the masses." While it's true that if once assumes plane flight is necessary to all, then cost will matter more to those with less resources, but my time is as valuable to me as it is to any person of greater privilege absent that necessity, which is why I don't look to fly at all anymore since my time is treated as almost worthless by airline companies and any "need" I'd have to travel by air is largely illusory, driven by desire rather than physical demand. I'll skip the vacations in Maui or visits home to save myself a day of purposelessness in the hell of airports and airplanes. (Of course I also understand that option isn't the same for everyone.)
posted by gusottertrout at 7:35 AM on December 14, 2017 [2 favorites]


Also, planes fly slow because people don't like sonic booms. You can't go supersonic over land in the US. You could build a much better Concorde today and half the flight time from NY to LA if you could go supersonic.
posted by leotrotsky at 10:17 AM on December 14 [1 favorite +] [!]


You'd also quadruple or quintuple your fuel consumption for a not-equivalent gain in revenue-per-seat-mile.

Transsonic and supersonic make more economic sense for flights to the other side of the globe, but not domestically.
posted by Thistledown at 7:36 AM on December 14, 2017 [5 favorites]


The second video explained what's been bugging me for a long time: why flights to/from the US to South America are vastly more expensive than a similar duration flight to Europe, for example. Very interesting!
posted by Liesl at 7:41 AM on December 14, 2017 [1 favorite]


"So I'm on the plane, we left late. Pilot says we're going to be making up some time in the air. I thought, well isn't that interesting. We'll just make up time. That's why you have to reset your watch when you land. Of course, when they say they're making up time, obviously they're increasing the speed of the aircraft. Now, my question is if you can go faster, why don't you just go as fast as you can all the time? C'mon, there's no cops up here, nail it. Give it some gas! We're flying!" - Jerry Seinfeld
posted by Servo5678 at 7:51 AM on December 14, 2017 [7 favorites]


I seem to have missed something - is he saying that the planes today are worse, efficiency-wise, than the planes in the 1960s? He never goes back to the 60s planes or compares them directly, and it's not clear in which era the engines he mentions are/were used. So for me the question was never answered or I just don't understand the answer. Why do they fly slower today than in the 60s? The Concorde is a derail since it never flew from NY to LA.
posted by AFABulous at 7:54 AM on December 14, 2017 [4 favorites]


Concorde basically stopped flying after the Air France 4590 crash.
posted by carter at 7:58 AM on December 14, 2017


Haven't watched it (sorry, no time?), but I always assume it's so they can increase their on-time arrival stats.
posted by allthinky at 8:02 AM on December 14, 2017


Interesting, but riddled with crap - particularly when he talks about Turbojets and implies that's what power modern fighters.

Or that high-bypass turbofans on airliners get most of their thrust from the engine core, which AFAIK hasn't been true for decades.

is he saying that the planes today are worse, efficiency-wise, than the planes in the 1960s?

No, just not faster.

Why do they fly slower today than in the 60s?

The tl;dr about that seems to be: they don't actually fly any slower. The published departure and arrival times have more slack in them for longer toodling around airports, more waiting in line for takeoffs and maybe circling for a landing time, etc.

It's probably also the case that airlines' posted times now simply have to be more accurate by law than they did in the 1960s.
posted by GCU Sweet and Full of Grace at 8:02 AM on December 14, 2017 [10 favorites]


His stuff about Concorde misses the fact that BA were still making a hefty profit on theirs even after they returned to flight after the 2003 accident

Correct me if I'm wrong, but BA's regular scheduled LHR-JFK-LHR runs also lost boatloads of money from what I recall. Even when the flights were full, half the people on the plane used miles to get their ticket. What made it profitable for BA to operate was wet leasing their aircraft to holiday charter operators who could offer cheap seats on a day of short hops around the country or flights to some sunny places in Europe and North Africa.

There didn't seem to be any similar market in France for that sort of thing.

But yeah, in the end it's all about fuel cost. If it were possible to build a supersonic transport aircraft that used the same fuel per seat mile as a 757 or similar it might be doable for now. For it to have a real future it would have to be closer to the 787's operating cost. Fuel cost is why we didn't get back an hour or so on transoceanic flights back in the early 2000s. The sudden jump in fuel cost got us the 787 instead of the Sonic Cruiser, which had a design cruise speed of about Mach 0.98 while using the same fuel per seat mile as a 767/777 class aircraft. After 9/11 they used some of the same techniques to improve fuel consumption at lower speed instead and after much BS due to excessive outsourcing we finally got the 787.
posted by wierdo at 8:04 AM on December 14, 2017 [1 favorite]


Another interesting perspective on this is the first third of (Metafilter's own) Maciej Cegłowski's Web design - the first 100 years.
posted by Homeboy Trouble at 8:05 AM on December 14, 2017 [9 favorites]


Or that high-bypass turbofans on airliners get most of their thrust from the engine core, which AFAIK hasn't been true for decades.


Literally 100% of the energy that propels a jet aircraft is generated in the engine core. A high bypass turbofan adds turbine stages (relative to a low bypass model or straight turbojet) to bring the core exhaust energy down as low as possible to cut down on noise and increase propulsive efficiency by using the giant fan that propels air at a velocity much closer to that the plane flies at rather than the uselessly excessive speed that normally comes out, wasting much energy as heat and noise. Thing is that it's literally impossible to make them even as efficient as a turboprop. They're just faster and less annoying to ride on than most turboprops, but something like 20% less efficient.

That said, it is true that very little of the thrust in a turbofan comes out the turbine exhaust since literally as much as is possible, without causing problems with the airflow in the engine stalling, is extracted to provide the energy to drive the fan.
posted by wierdo at 8:13 AM on December 14, 2017 [2 favorites]


Yeah, that is what I meant and stated inelegantly. Spasibo.
posted by GCU Sweet and Full of Grace at 8:19 AM on December 14, 2017 [1 favorite]


I guess what I'm saying is that in reality all turbojet engines work the same way. The differences come in with how you make use of the energy generated by the combustion process. You can either use it directly as in a straight turbojet, turn as much as is possible into mechanical energy as in a turboprop or turboshaft, or do some combination of the two, as in a turbofan.
posted by wierdo at 8:23 AM on December 14, 2017 [1 favorite]


That How Airlines Schedule Flights video was way more interesting than I would have expected.
posted by COD at 8:25 AM on December 14, 2017 [4 favorites]


This is all true about the current state of the industry being quite sad, and their seeming lack of progression since the 60's, but flights are cheaper, the hub and spoke model is not as popular as it once was, which drastically reduces travel time. While legroom in economy is worse than ever, business class on international flights has lie-flat seating and Netflix.

Still, a story lamenting the current state of the industry and the death of the Concorde could mention Boom Supersonic who wants to launch a new/modern supersonic jet by 2023.

However, the supersonic jets are more of the same. SpaceX, with its far cheaper launch costs, is proposing to bring travel time from anywhere in the world to anywhere else in the world down to less than an hour by taking people briefly to space.
posted by fragmede at 8:56 AM on December 14, 2017 [2 favorites]


One interesting thing they left out of "How Airlines Schedule Flights" is that Abu Dhabi airport. All those flights happen at local nighttime.

Why? This may not be obvious unless you've had to fly out of Las Vegas or Phoenix in the summertime during the day (and had your flight delayed or cancelled)


I had a 9am flight out of Las Vegas in June once. I had gotten maybe 3 hours of sleep the night before because bachelor party. I was also, unsurprisingly, extremely hung over. You could see the heat waves coming off the tarmac. The first hour or so of that flight was extremely rough because of the low-density air, and coupled with the gassy ex-marine who had clearly been drinking screwdrivers the night before it made for the most awful flight of my life.
posted by grumpybear69 at 9:00 AM on December 14, 2017 [3 favorites]


Homeboy Trouble, that link is worth it for "White Nerd's Burden" alone. Thanks!
posted by clawsoon at 9:12 AM on December 14, 2017 [1 favorite]


That was interesting, thanks for posting it.

One direction I was hoping it would go is why there haven’t been any breakthroughs in airplane propulsion in the last 60 years. Having the top of the efficiency curve land just below the transonic gap — or above it — would be extremely useful for time sensitive items such as troops and materiel so there is at least some impetus (heh) to be working on the problem.

Also, speedier passenger flights mean you can move more passengers per day with the same number of planes. So while I can understand the benefits of bigger planes on well travelled routes, it seems like regional airlines could benefit from speed too.
posted by Tell Me No Lies at 9:31 AM on December 14, 2017 [1 favorite]


They didn't go into it much, but the fact that airlines like Southwest fly short-hop routes means flight time can't really be improved that much by going faster. As an example, American Airlines has 8 daily flights between New York and LA, but Southwest has 19 daily flights between Dallas and Houston. So the number of short haul flights dwarfs cross-country where speed matters. Flying from LAX to Las Vegas for example is only about 30 minutes at cruising altitude, the rest of the hour-long flight is ascending and descending.

So yeah, if the majority of flights in the US were cross-country then I think you would see airlines trying to whittle that time down. But they aren't, so they don't.
posted by The_Vegetables at 10:08 AM on December 14, 2017


When it is cheaper and quicker to drive a 1985 VW Westfalia fom SLC to Bakersfied, then you know there are more factors than airspeed. The last time I tried flying that I found my self standing on the runway in San Francisco, in the rain at the twelve hour mark. United had overbooked the airspace and promised an arrival next day. My daughter called them and made a case for frailty and possible confusion that got me to LA, then onto a three hour shuttle ride back to Bako, arriving at 7:30 PM. I drove to the SLC airport at 4 AM, expecting to be with family at 10:30 AM after a 6AM takeoff. This is the flight where I heard a male voice speaking from the cockpit, to say, "Well, I can FLY the plane!"
posted by Oyéah at 10:14 AM on December 14, 2017 [1 favorite]


They didn't go into it much, but the fact that airlines like Southwest fly short-hop routes means flight time can't really be improved that much by going faster.

Hmm, good point.
posted by Tell Me No Lies at 10:30 AM on December 14, 2017


It's our damn fault really. Planes go slower due to the fact people only buy the cheapest possible ticket. So airlines now compete on cost. Since people only buy plane tickets based on costs

Before deregulation the costs to the consumer was fixed, so the airlines needed to compete on speed and luxury. Now there is no point, they go slower to save on fuel to make the flight cheaper in costs.
posted by jmauro at 10:43 AM on December 14, 2017 [2 favorites]


The second link explains why every international flight I take seems to connect through LAX, instead of the far preferable option of never connecting through LAX. IMO a small amount of increased time spent in the air isn't nearly the issue that the the vastly increased time on the ground dealing with security is.
posted by surlyben at 11:00 AM on December 14, 2017


Ugh Wendover videos are the perfect example of an entire genre of YouTube videos that are really bad for society. Like it's an amateur who thinks he understands a subject but really really doesn't, explaining a topic in a fundamentally flawed way to a bunch of people who will now smugly think they've gained something but have in actuality learned nothing. All driven by ad revenue.
posted by danny the boy at 11:01 AM on December 14, 2017 [15 favorites]


Like all the science-lite videos on YouTube are oversimplified and treat actual understanding as optional, but at least they encourage enthusiasm and curiosity about the world. This kind of shit just enables know-it-all-ism but with incorrect information. It's the Reader's Digest we deserve.
posted by danny the boy at 11:06 AM on December 14, 2017 [6 favorites]


If pure fuel efficiency and speed are the sole criteria the very simple ram jet engine is by far winner (per an ancient encyclopedia) but has a bunch of other issues. Only works over 600mph? and pretty darned noisy. Always wondered how it got up to 600mph.

I saw an account (here or Mr Leff) about badly delayed flight from like Singapore to Houston (5-7 hours) that took a circuitous route over south america, found good wind at high altitude, and landed early. But most planes are like trains, if one moves faster it messes the entire system. Could go much faster 20000 feet higher if the pilots were willing to wear oxygen masks the entire trip.
posted by sammyo at 11:38 AM on December 14, 2017


At one point the narrator talks about turbofans but shows a plane with an oval engine nacelle -- the kind you use for opposed piston engines.
posted by Monday, stony Monday at 11:46 AM on December 14, 2017 [2 favorites]


the very simple ram jet engine is by far winner (per an ancient encyclopedia) but has a bunch of other issues. Only works over 600mph? and pretty darned noisy. Always wondered how it got up to 600mph.

Presumably pure ramjets would be boosted to useful speed by a carrier aircraft, disposable rockets, or something of that ilk.

There's a good video about the turboramjets the A-12/SR-71 family used, but the tl;dr is that it's a turbojet surrounded by a larger nacelle. At "low" speeds, the air is compressed a little bit by speed + the inlet design and all the air flows through the engine core where it's further compressed in the usual way. At high mach, the air compression from speed + inlet design is high, so lots (most?) of the pre-compressed air is routed around the engine core and straight into the afterburner section where it's mixed with fuel and ignited.
posted by GCU Sweet and Full of Grace at 12:23 PM on December 14, 2017 [1 favorite]


(I may be misremembering and maybe the air is routed from an early compressor stage to the afterburner? Either way it bypasses at least *most* of the engine core)
posted by GCU Sweet and Full of Grace at 12:24 PM on December 14, 2017


On really hot days, the air is much less dense ...

A friend told me a story one time about flying out of Reno and wondering why they had a 10,000 foot runway. (Wikipedia shows the longest runway is currently 11,002 feet.) They took off on a fine, sunny afternoon, lifted off, and flew in ground effect for what seemed like a really, really long time before they actually started climbing. Turns out the density altitude that day was 9,000 feet, as compared to the 4,415 feet actual altitude.
posted by Bruce H. at 12:46 PM on December 14, 2017 [1 favorite]


At one point the narrator talks about turbofans but shows a plane with an oval engine nacelle -- the kind you use for opposed piston engines.

The air inlets on 737 engines are not round due to ground clearance reasons. Remember that it was originally designed to use much smaller diameter low bypass turbofan engines. To be able to fit a high bypass turbofan without causing a completely intractable FOD problem, they built the inlet such that it is mostly flat at the bottom so as to change the way the air flows into the engine on the ground. It's akin in function to the inertial separator found on a lot of turboprops.
posted by wierdo at 5:50 PM on December 14, 2017


And yes, dude sometimes gets his details wrong, but I have yet to see a video of his that is blatantly misinformed and gets the central thesis wrong.

Yeah, a 30 minute or hour long documentary will be much more complete, but there is value in having a basic knowledge of the way the world and the things within it work, even at a somewhat dumbed down level when the underlying ideas are too complex to convey directly and accurately in a video or even book of any reasonable length. Brains are great at figuring out how to do things given incomplete knowledge, so having some knowledge of many topics is helpful even in a practical sense.

That said, videos like this are often as much a place to start to see if the thing is even at all interesting before moving on to more substantial sources on YouTube and elsewhere. (There is so much physics geekery on YT, it's ehrmaaazing)
posted by wierdo at 5:58 PM on December 14, 2017 [3 favorites]


The tl;dr about that seems to be: they don't actually fly any slower.

Actually, modern airliners do fly a little slower than their jet-age 707 and DC-8 counterparts. However, contemporary engines are quieter and more efficient.

Before deregulation the costs to the consumer was fixed, so the airlines needed to compete on speed and luxury. Now there is no point, they go slower to save on fuel to make the flight cheaper in costs.

Which is why Boeing cancelled the Sonic Cruiser.

the fact that airlines like Southwest fly short-hop routes means flight time can't really be improved that much by going faster.

Well, sure, if we're restricted to flying those short-hop routes.
posted by Rash at 8:54 PM on December 14, 2017


surlyben: Fly Air New Zealand, they go through SFO. SO MUCH BETTER when I was dealing with possible Travel Ban bullshit earlier this year (they didn't care).
posted by divabat at 1:18 AM on December 15, 2017


I thought the second "Bonus" video was the more interesting one: learned some new stuff about "banking" flights and "scissor hubs".
posted by TheophileEscargot at 3:07 AM on December 15, 2017 [1 favorite]


weirdo, it wasn’t a 737 that was misidentified as a turboprop (?). There was video of a twin engine Cessna or similar running under the explanation of turboprops, even though it is a piston engine. Is it so hard to get stock video of a De Havilland Dash 8?
posted by chrchr at 6:48 AM on December 15, 2017


It's been a bit since I have watched the video, so I probably shouldn't have been so snarky about it.

And upon rewatching, I'm assuming you're talking about the aircraft we see for a second or two just after he starts talking about turboprops. You're right that that does look more like a piston twin, but I think it's a King Air, though the wing looks a bit off from what I remember. Can't say I have ever stood in front of one on takeoff, though, or ever for that matter. I only ever saw them from the left side and the inside, lol.
posted by wierdo at 8:32 AM on December 15, 2017


And yes, dude sometimes gets his details wrong, but I have yet to see a video of his that is blatantly misinformed and gets the central thesis wrong.

How about the one that is the subject of this FPP and the one we're all talking about?

Like the question he purports to answer, which is the title of the video, is why planes are slower today than they were 50 years ago. He gives one sentence that hints at the actual answer before spending the entire rest of the video talking about engine types and fuel efficiency (poorly), all of which don't actually answer the question. It's all signifiers of knowledge, which hook up to interesting things you personally may know as an aviation wonk but the general audience does not.

Planes aren't slower because people prefer to pay less than get somewhere faster. Like, think about that idea for a minute and consider how you might prove something like that. The only example where consumers had the choice of a faster more expensive flight on the same route was the Concorde, and... that was commercially successful until the early 2000's, far into the modern era of flying.

Planes aren't slower at all, but it takes longer to get going because there are far more passengers and flights. Air passengers tripled between the 70s and 2011, because deregulation worked--ticket prices dropped by half since 1978.

The video is worse than incorrect. It's just... incoherent.
posted by danny the boy at 10:19 AM on December 15, 2017 [5 favorites]


It mentions Concord without mentioning that its speed necessitated it having an entirely separate flight path into and out of airports. I don't know the details of it, but my understanding is that it basically couldn't slow down enough to go into the standard stacking/queuing system (please correct me if I'm wrong). As mentioned by backseatpilot, congestion is an issue; I presume that reintroducing commercial jets would be a headache as they need a different window to every other plane you're trying to organise.
posted by Vortisaur at 2:47 PM on December 15, 2017


Yeah, except it is in fact true that it does take longer to get somewhere then it used to and it isn't just increased block time due to newish FAA regs on delay calculations. (Until the regulatory change, block times were still longer, though shorter than they were in the late 90s when congestion was last extremely high but the newer airspace efficiency measures had not yet been implemented.

But yes, if you disagree with what a video is saying you will quite obviously think it's shit whether your disagreement is based in reality or not. Luckily, nobody is holding your eyes open and make you watch any of this sort of content. And happily, despite your disagreement, it is in fact true that planes fly slower now then they used to. Not because they can't fly faster, but because airlines intentionally fly more slowly to save fuel. I remember quite well the day AA finally convinced their pilots to stop hooning. It started taking an extra 15 minutes in the air to get between DFW and my home airport a few hundred miles away. Fokker, MD-80, 757, 767, or E-jet it didn't matter. Flights that used to take 20 minutes of flight time when they used maximum power for takeoff and flew as fast as was legal and safe started taking 30-35 when they started doing the minimum power takeoffs that everyone does these days and also reduced the allowable cruise power usage, whereas the previous procedure was, as in every plane, to use maximum cruise power absent some specific reason to use a lower power setting. Some of that slowness has been offset with more efficient arrival and departure procedures for flights under IFR developed in the intervening years, but by no means all.

Moreover, if you bothered to look at the entirety of the jet market you'd not that commercial planes are not getting faster, yet private jets are. That's all about economics. Point being that no, the video is not incoherent, it in fact covers the biggest single driver in why it takes longer to fly somewhere now than it used to. I would have liked it if the video also covered the secondary causes, but not covering them doesn't make the video incorrect or incoherent, just somewhat superficial.
posted by wierdo at 7:03 AM on December 16, 2017


Also, if you listen to the airlines of course it's all about congestion. That isn't seen as their fault, although it actually is since they choose where to fly and how often. If they told everyone their flight was going to be 10% longer because the airline was choosing to make them listen to the screaming baby that much longer people would be incensed given the billions of dollars a year the airlines have been making lately now that they've finally gotten rid of most of the competitors in the market and the ever increasing add-on fees continue their expansion.
posted by wierdo at 7:11 AM on December 16, 2017


A sign of our gilded times, Lockheed Martin has signed on as a partner in a venture to build supersonic business jets. So people who can afford to fly in supersonic planes will be limited to people who can afford their own damn plane.
posted by peeedro at 9:37 PM on December 16, 2017


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