Pilots know about this and so do airports, it's a part of any navigation system.
Magnetic poles wander a little each year. Around most of the world that translates to a degree or so of drift per year (in some places it can be 2-3, if you're closer to the pole)
A 60-year old runway like at Wichita will have been renamed several times. Yes the signage needs changing but it needs periodic replacement due to weathering anyway.
They're getting better all the time - and if the civilian ones are as good as we're seeing now that means the military lenses are an order of magnitude better.
"They also have trouble with cloud cover."
Nope. Clouds are transparent at certain IR and radio frequencies. You don't have to rely soley on 400-900nm
"A turn-around time of three days on a satellite would be astounding. "
Then be astounded, because satellites have been achieving that for a decade at least. The trick is to use more than one.
"Just burn their sensors and communications equipment, and let their orbit decay. "
Or their fuel tanks/reaction wheels - bigger/easier targets and if you can pinhole the fuel tank then it's only got ion thrusters to work with - which moves it into "predictable orbit" territory and probably wont be interpreted by the owners as a hostile action (more likely a bit of debris)
if I take the plane, I have to pay more than that difference to get to the airport in London - and be there 3 hours ahead of time and only have 20kg (10kg with some airlines)
If going to amsterdam by air the train from Schipol is free (but the train from London probably passed through schipol 15 minutes earlier.
If going to paris, the subway fares in from the airports Paris and London would more than make up the difference.
The primary reason twin beats quad at any given size is simple: Mass.
Both of the extra two engines and the wing structure to hold them. The extra fuel consumption factors in too, but it's not that much extra fuel consumption.
Given you have a MTOW based on what the wheels and runway can handle, losing mass to engines+support structures means that much less revenue freight, fuel or self-loading freight can be carried.
The A380 _can_ do that - its takeoff and landing speeds are 20-35 knots slower than the 747.
However they _don't_ do that.
It's better for the engines (maintenance wise and therefore cost-wise) to use just enough power to takeoff in the available runway length than to punch it and use the shortest possible length. It's also better for the neighbours' hearing.
Watch any airport and you'll see that despite massive differences in power and size, all aircraft tend to take off about the same point. TOGO power is only used when things go pearshaped.
The A319 was discontinued long before the Bombardier acquisition started. They weren't selling enough of them to make it worthwhile as downsizing an aircraft results in higher per-seat costs.
"That tanker contract was contested, multiple times, and after multiple rounds and bids Boeing won"
Primarily because Airbus walked away when it was made clear that no matter how many times they won on technical grounds, it will be challenged and killed on politics.
In the meantime they made and sold a bunch of A330 Voyager tanker/transports to other militaries, so they didn't lose any money on R&D for the competition. One of the huge cost savers of the Voyager over every competing craft is that because the wing is common to A330 and A340, there are 2 built in "free" wing hardpoints for fuelling with no heavy re-engineering needed to make use of them (being designed for engine mounts, they're significantly _over_ engineered for this purpose.)
R&D spent on the A380 was directly applied to the A350XWB, shortening the development cycle and reducing costs substantially. It also had a lot of input into the NEO programs.
They may never recover the R&D costs on direct A380 sales, but they've already covered them on A350 preorders.
> while Boeing sat there and said "cost-per-seat is gonna be too fucked up with supersonic...let's just build a really big, efficient plane."
Um, no. Boeing was set a target by the US government of building a transport that was both 50% faster than concorde and carried twice as many passengers, over twice the range.
The passenger load and range was probably doable, but Concorde was about as fast as it was technically possible to reliably fly using metallurgy of the day (Before anyone says "SR71", I'll just mention all that fuel pouring out onto the runway and the fact that it had to be refuelled after takeoff before it could do anything meaningful and about every 90 minutes after that when travelling at speed))
The 747 was a backstop freighter design derived from a scaled-up 707 for a military contract competition and only intended to sell 2-300 or so whilst they got their SST flying. The Hump was only there to allow a nose door. They weren't expecting Juan Trippe to say "I'll take two dozen kitted out for passengers!"
Concorde and the Boeing SST were pretty much the last time that makers built what governments told them to, vs asking the airlines what they really wanted and building that.
"If you go back 20 years ago when the A380 was being proposed "
Go back a decade further. It was being actively pitched at about the launch size when I started pilot training in 1990 and Airbus had feelers out for a few years earlier than that (Trent 800 and 1000 were actively promoted as design targets for the A3XX at the start of Trent production in the early 1990s). Virtually every large airline in the world was expressing interest or making preorder noises.
Large aircraft design and production involves very long-distance crystal ball gazing and risk calculation.
Back at that point the 747 was the only game in town for Trans-pacific flights and ETOPS was only viable across atlantic and islandhopper routes. Most airlines were still using 747s on transoceanic and islandhopper flights not so much due to distrust of ETOPS as the risk of being stranded at XYZ tiny island if there was an engine failure
If you've ever seen how much of an event each 747 flight was and the issues involved in getting 300+ people off and on these aircraft, 1-2 immigration officials on duty, along with local acommodation only being able to take a fraction of them due to most passengers simply passing through, you'll understand those concerns. It wasn't unusual for 200+ passengers to have to bunk down in the airport lounge when breakdowns occurred simply because there was nowhere else to put them.
On top of that fuel prices were only going in one direction - upwards - and stayed that way until just before the first A380s were launched.
Trains have far more doors per passenger than aircraft.
A train carrying 1000 passengers will typically have 40 doors PER SIDE
WRT china's pressurised trains, yes they're pressurised but the difference between inside and outside isn't particularly high and unlike aircraft the mass of door mechanisms/pressurisation equipment isn't an issue.
Or 1088 if you're not careful about counting passengers when loading (operation Solomon)
The limit on capacity is set by evacuation time, not by seating. The 830 capacity of the A380 was determined by running practice evacuations and counting how many could get out in 90 seconds. The actual seating capacity if you used 777 sardine class is in excess of 1200.
Depending what you're flying in even a 737 can be bad (hot day, thermals lifting up the wake on approach, flying 5-6 minutes behind in a PA-38 == unpleasant)
Those big empty spaces are there for an important reason - space below decks for freight.
A fully-stuffed A380 has 6 spaces for cargo containers after passenger baggage is loaded, but can still carry twice the cargo mass of a similarly-stuffed 777 at MTOW, over a much longer distance.
By reducing seat count to ~500, space is freed up below decks to carry freight and you can use the space above decks to offer better seat pitch and halo accomodation at no cost - most of the time that halo accomodation isn't sold so goes to some lucky frequent flier as a fantastic advertising gimmick. When they do sell it, the halo space is a nice sidestream earner.
Freight is significantly more profitable than passengers, doesn't complain about being bumped to the next flight and doesn't have to be loaded/unloaded in 15 minutes (quite apart from the catering costs) It also fills an aircraft more reliably than passenger flows.
This cargo issue is the primary disadvantage of double passenger decking on a long-haul aircraft. The aircraft would have benefitted significantly from double freight decking and combi conversions may well do so. Freighter designs do make provisions for 3 layers of containers, even though none are flying.
The development costs of the A380 are kind of interesting, as much of the R&D turned out to be directly relevant to the other lines it made and substantially shortened the development cycle of the A350XWB (as well as the development costs) - to the point that the savings on that aircraft probably make up for what the A380 incurred - and that's before considering how much the A330/A320NEO programs benefitted.
In fact, even before the A380 launched there was virtually nothing older than 747-400 left in revenue cargo/passenger service and airlines were retiring those at 15 years old.
The size of this market is small. Small enough that Boeing as first to market, owned that market. McD-D and Lockheed both found that out the hard way when they tried to muscle in.
One of the main things that is in Airbus' favour about the A380 is that unlike Boeing, McD-D, or Lockheed, it didn't "bet the farm" on the success of the A380. Had the 747 commercially failed, Boeing wouldn't exist. Airbus can afford to continue producing the A380 as a halo product even if there isn't sufficient demand to justify the reengineering for a NEO.
"Airbus has sold a comparable number of A320 family aircraft as Boeing has the 737, and they did it while Boeing enjoyed a 20 year head start. How's that not a successful product?"
Not only that, but the backlog of orders for A320 is higher than for 737
Airbus could sustain another 2 assembly A320 assembly lines without much difficulty and now they're venturing into a market that Boeing doesn't even operate in (100-seats) with the Bombardier purchase that has a large degree of interest as the world's turboprop fleet is aging out.
"When I fly from the Netherlands to London I have a choice between 4 source airports and 4 destination airports (or a train)."
I usually take the train - even before the dedicated HS lines were completed between France and A'dam it was only an hour longer doorstep to doorstep, with far less hassle and more scenery.
London to Paris or Brussels is almost always faster by train than by air, far less stressful and by the time all the costs are added up, usually cheaper than flying+ancilliary costs.
Once oil costs start ramping up again, the economics of trains with electric power supplies will start winning out over the time savings for longer distances. It's a different story in the USA where long distance trains generally operate at speeds which europeans associate with rustic rural backwater lines (frequently even slower than Indian railways infamously slow systems).
"Emirates fleet and network is the product of other countries protectionism"
Which makes the point that whilst major aircraft makers are frequently (and justifiably) accused of being government subsidised (it's a matter of national pride to have this kind of technology), many/most international airlines are similarly subsided via the backdoor with preferential deals as a matter of national pride/publicity/flagwaving
(Before anyone says US airlines are not, the fact that foreign operators are prohibited from flying revenue domestic legs is one example of this kind of protectionism/backdoor subsidisation)
"What US airlines have found, however, is that it's a heck of a lot cheaper to fly back and forth between regional airports"
The A380 is not a regional flier - it's a specifically tasked intercontinental loadhauler - and when you start flying intercontinental routes (even with big twins) you don't often fly from or to regionals as you start running into the same risky economics as you get with the big birds. Any segment less than 5-6 hours is on dodgy economic grounds even with a full load in a A380.
The bigger problem with the A380 is both that it's the right aircraft at the wrong time, and that just as in road haulage there are a lot more sales opportunities for smaller aircraft than larger ones - but having the larger ones means that you can sell more smaller ones on the basis of fleet uniformity (Airbus have unified cockpits and operators prefer to stick to one type of engine to keep maintenance prices down)
If fuel prices hadn't crashed it would be more popular. If they rise back to historic levels then it probably will be.
NEO would be a lot more doable if the engines have the same mounting and electronics interfaces as the existing ones, are not significantly larger (ie, don't need landing gear mods) and the efficiency gains don't come with significant mass penalties (embedded 20-30MW gearboxes are _heavy_) requiring that longer legs be flown to realise the efficency gains (this is the same reason why shorthaul aircraft don't have substantial winglets: The mass penalty outweighs the efficiency gain over the average flight leg)
Part of the problem there is that Trents are very good cores but P&W have the gearbox tech plus superlight fans, and there's no way you can mate the two parts together to produce a sum greater than the parts. For turboprops and suchlike you don't have that problem inasmuch as you can take engine from one maker and propellor from another (and in fact, usually do), but a turbofan is a complete packaged solution, so buyers are at the mercy of an individual maker's strengths, weaknesses and patent portfolios.
Slashdot Mirror
Pilots know about this and so do airports, it's a part of any navigation system.
Magnetic poles wander a little each year. Around most of the world that translates to a degree or so of drift per year (in some places it can be 2-3, if you're closer to the pole)
A 60-year old runway like at Wichita will have been renamed several times. Yes the signage needs changing but it needs periodic replacement due to weathering anyway.
"North Koreans have been able to avoid detection of sensitive equipment by moving it while spy satellites are not overhead"
That's not unusual. All the militaries do this.
The only countermeasure is to increase the number of satellites so they can't do anything useful between passes.
"Satellites take forever"
Only if you have one or two of them.
"and the pixels are really chunky."
They're getting better all the time - and if the civilian ones are as good as we're seeing now that means the military lenses are an order of magnitude better.
"They also have trouble with cloud cover."
Nope. Clouds are transparent at certain IR and radio frequencies. You don't have to rely soley on 400-900nm
"A turn-around time of three days on a satellite would be astounding. "
Then be astounded, because satellites have been achieving that for a decade at least. The trick is to use more than one.
"Just burn their sensors and communications equipment, and let their orbit decay. "
Or their fuel tanks/reaction wheels - bigger/easier targets and if you can pinhole the fuel tank then it's only got ion thrusters to work with - which moves it into "predictable orbit" territory and probably wont be interpreted by the owners as a hostile action (more likely a bit of debris)
if I take the plane, I have to pay more than that difference to get to the airport in London - and be there 3 hours ahead of time and only have 20kg (10kg with some airlines)
If going to amsterdam by air the train from Schipol is free (but the train from London probably passed through schipol 15 minutes earlier.
If going to paris, the subway fares in from the airports Paris and London would more than make up the difference.
"Speculations I've seen"
The primary reason twin beats quad at any given size is simple: Mass.
Both of the extra two engines and the wing structure to hold them. The extra fuel consumption factors in too, but it's not that much extra fuel consumption.
Given you have a MTOW based on what the wheels and runway can handle, losing mass to engines+support structures means that much less revenue freight, fuel or self-loading freight can be carried.
The A380 _can_ do that - its takeoff and landing speeds are 20-35 knots slower than the 747.
However they _don't_ do that.
It's better for the engines (maintenance wise and therefore cost-wise) to use just enough power to takeoff in the available runway length than to punch it and use the shortest possible length. It's also better for the neighbours' hearing.
Watch any airport and you'll see that despite massive differences in power and size, all aircraft tend to take off about the same point. TOGO power is only used when things go pearshaped.
When an A380 does punch it, you'll know about it.
The A319 was discontinued long before the Bombardier acquisition started. They weren't selling enough of them to make it worthwhile as downsizing an aircraft results in higher per-seat costs.
"That tanker contract was contested, multiple times, and after multiple rounds and bids Boeing won"
Primarily because Airbus walked away when it was made clear that no matter how many times they won on technical grounds, it will be challenged and killed on politics.
In the meantime they made and sold a bunch of A330 Voyager tanker/transports to other militaries, so they didn't lose any money on R&D for the competition. One of the huge cost savers of the Voyager over every competing craft is that because the wing is common to A330 and A340, there are 2 built in "free" wing hardpoints for fuelling with no heavy re-engineering needed to make use of them (being designed for engine mounts, they're significantly _over_ engineered for this purpose.)
R&D spent on the A380 was directly applied to the A350XWB, shortening the development cycle and reducing costs substantially. It also had a lot of input into the NEO programs.
They may never recover the R&D costs on direct A380 sales, but they've already covered them on A350 preorders.
> while Boeing sat there and said "cost-per-seat is gonna be too fucked up with supersonic...let's just build a really big, efficient plane."
Um, no. Boeing was set a target by the US government of building a transport that was both 50% faster than concorde and carried twice as many passengers, over twice the range.
The passenger load and range was probably doable, but Concorde was about as fast as it was technically possible to reliably fly using metallurgy of the day (Before anyone says "SR71", I'll just mention all that fuel pouring out onto the runway and the fact that it had to be refuelled after takeoff before it could do anything meaningful and about every 90 minutes after that when travelling at speed))
The 747 was a backstop freighter design derived from a scaled-up 707 for a military contract competition and only intended to sell 2-300 or so whilst they got their SST flying. The Hump was only there to allow a nose door. They weren't expecting Juan Trippe to say "I'll take two dozen kitted out for passengers!"
Concorde and the Boeing SST were pretty much the last time that makers built what governments told them to, vs asking the airlines what they really wanted and building that.
"If you go back 20 years ago when the A380 was being proposed "
Go back a decade further. It was being actively pitched at about the launch size when I started pilot training in 1990 and Airbus had feelers out for a few years earlier than that (Trent 800 and 1000 were actively promoted as design targets for the A3XX at the start of Trent production in the early 1990s). Virtually every large airline in the world was expressing interest or making preorder noises.
Large aircraft design and production involves very long-distance crystal ball gazing and risk calculation.
Back at that point the 747 was the only game in town for Trans-pacific flights and ETOPS was only viable across atlantic and islandhopper routes. Most airlines were still using 747s on transoceanic and islandhopper flights not so much due to distrust of ETOPS as the risk of being stranded at XYZ tiny island if there was an engine failure
If you've ever seen how much of an event each 747 flight was and the issues involved in getting 300+ people off and on these aircraft, 1-2 immigration officials on duty, along with local acommodation only being able to take a fraction of them due to most passengers simply passing through, you'll understand those concerns. It wasn't unusual for 200+ passengers to have to bunk down in the airport lounge when breakdowns occurred simply because there was nowhere else to put them.
On top of that fuel prices were only going in one direction - upwards - and stayed that way until just before the first A380s were launched.
Trains have far more doors per passenger than aircraft.
A train carrying 1000 passengers will typically have 40 doors PER SIDE
WRT china's pressurised trains, yes they're pressurised but the difference between inside and outside isn't particularly high and unlike aircraft the mass of door mechanisms/pressurisation equipment isn't an issue.
"Max capacity of a 747 is over 500."
Or 1088 if you're not careful about counting passengers when loading (operation Solomon)
The limit on capacity is set by evacuation time, not by seating. The 830 capacity of the A380 was determined by running practice evacuations and counting how many could get out in 90 seconds. The actual seating capacity if you used 777 sardine class is in excess of 1200.
"wake turbulance it has nothing on a 757"
Depending what you're flying in even a 737 can be bad (hot day, thermals lifting up the wake on approach, flying 5-6 minutes behind in a PA-38 == unpleasant)
Those big empty spaces are there for an important reason - space below decks for freight.
A fully-stuffed A380 has 6 spaces for cargo containers after passenger baggage is loaded, but can still carry twice the cargo mass of a similarly-stuffed 777 at MTOW, over a much longer distance.
By reducing seat count to ~500, space is freed up below decks to carry freight and you can use the space above decks to offer better seat pitch and halo accomodation at no cost - most of the time that halo accomodation isn't sold so goes to some lucky frequent flier as a fantastic advertising gimmick. When they do sell it, the halo space is a nice sidestream earner.
Freight is significantly more profitable than passengers, doesn't complain about being bumped to the next flight and doesn't have to be loaded/unloaded in 15 minutes (quite apart from the catering costs) It also fills an aircraft more reliably than passenger flows.
This cargo issue is the primary disadvantage of double passenger decking on a long-haul aircraft. The aircraft would have benefitted significantly from double freight decking and combi conversions may well do so. Freighter designs do make provisions for 3 layers of containers, even though none are flying.
The development costs of the A380 are kind of interesting, as much of the R&D turned out to be directly relevant to the other lines it made and substantially shortened the development cycle of the A350XWB (as well as the development costs) - to the point that the savings on that aircraft probably make up for what the A380 incurred - and that's before considering how much the A330/A320NEO programs benefitted.
There aren't any 47-year old 747s flying.
In fact, even before the A380 launched there was virtually nothing older than 747-400 left in revenue cargo/passenger service and airlines were retiring those at 15 years old.
The size of this market is small. Small enough that Boeing as first to market, owned that market. McD-D and Lockheed both found that out the hard way when they tried to muscle in.
One of the main things that is in Airbus' favour about the A380 is that unlike Boeing, McD-D, or Lockheed, it didn't "bet the farm" on the success of the A380. Had the 747 commercially failed, Boeing wouldn't exist. Airbus can afford to continue producing the A380 as a halo product even if there isn't sufficient demand to justify the reengineering for a NEO.
"Airbus has sold a comparable number of A320 family aircraft as Boeing has the 737, and they did it while Boeing enjoyed a 20 year head start. How's that not a successful product?"
Not only that, but the backlog of orders for A320 is higher than for 737
Airbus could sustain another 2 assembly A320 assembly lines without much difficulty and now they're venturing into a market that Boeing doesn't even operate in (100-seats) with the Bombardier purchase that has a large degree of interest as the world's turboprop fleet is aging out.
"747 was never popular as a passenger airplane for its capacity, it was popular because of its range"
To underscore that, 1000-passenger civil versions of the C5 Galaxy were proposed. No airline wanted them.
The 747 looks like a guppy. The A380 more like a plecostumus and the AN-225 looks like a sumo wrestler
There are a bunch of _far_ uglier aircraft in the sky.
"higher air pressure (I'll have to take that on trust since I had to give my barometer away to some bloody architect). "
FWIW, Most smartphones these days have one built in and they're surprisingly accurate (as is the calibration on their microphones)
"When I fly from the Netherlands to London I have a choice between 4 source airports and 4 destination airports (or a train)."
I usually take the train - even before the dedicated HS lines were completed between France and A'dam it was only an hour longer doorstep to doorstep, with far less hassle and more scenery.
London to Paris or Brussels is almost always faster by train than by air, far less stressful and by the time all the costs are added up, usually cheaper than flying+ancilliary costs.
Once oil costs start ramping up again, the economics of trains with electric power supplies will start winning out over the time savings for longer distances. It's a different story in the USA where long distance trains generally operate at speeds which europeans associate with rustic rural backwater lines (frequently even slower than Indian railways infamously slow systems).
"Emirates fleet and network is the product of other countries protectionism"
Which makes the point that whilst major aircraft makers are frequently (and justifiably) accused of being government subsidised (it's a matter of national pride to have this kind of technology), many/most international airlines are similarly subsided via the backdoor with preferential deals as a matter of national pride/publicity/flagwaving
(Before anyone says US airlines are not, the fact that foreign operators are prohibited from flying revenue domestic legs is one example of this kind of protectionism/backdoor subsidisation)
"What US airlines have found, however, is that it's a heck of a lot cheaper to fly back and forth between regional airports"
The A380 is not a regional flier - it's a specifically tasked intercontinental loadhauler - and when you start flying intercontinental routes (even with big twins) you don't often fly from or to regionals as you start running into the same risky economics as you get with the big birds. Any segment less than 5-6 hours is on dodgy economic grounds even with a full load in a A380.
The bigger problem with the A380 is both that it's the right aircraft at the wrong time, and that just as in road haulage there are a lot more sales opportunities for smaller aircraft than larger ones - but having the larger ones means that you can sell more smaller ones on the basis of fleet uniformity (Airbus have unified cockpits and operators prefer to stick to one type of engine to keep maintenance prices down)
If fuel prices hadn't crashed it would be more popular. If they rise back to historic levels then it probably will be.
NEO would be a lot more doable if the engines have the same mounting and electronics interfaces as the existing ones, are not significantly larger (ie, don't need landing gear mods) and the efficiency gains don't come with significant mass penalties (embedded 20-30MW gearboxes are _heavy_) requiring that longer legs be flown to realise the efficency gains (this is the same reason why shorthaul aircraft don't have substantial winglets: The mass penalty outweighs the efficiency gain over the average flight leg)
Part of the problem there is that Trents are very good cores but P&W have the gearbox tech plus superlight fans, and there's no way you can mate the two parts together to produce a sum greater than the parts. For turboprops and suchlike you don't have that problem inasmuch as you can take engine from one maker and propellor from another (and in fact, usually do), but a turbofan is a complete packaged solution, so buyers are at the mercy of an individual maker's strengths, weaknesses and patent portfolios.