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Boeing today is so obviously a different organisation to the one that built their rapidly dwindling reputation. The 747 was an amazing engineering marvel. They

Boeing today is so obviously a different organisation to the one that built their rapidly dwindling reputation. The 747 was an amazing engineering marvel. They started designing it in '65, the first one rolled off the production line in '68, and they were still making and selling them right up to 2023. I have a book here somewhere that talks about how so many of the design decisions were based on cold hard physics facts combined with engineering pragmatism. They needed to run the engine at peak efficiency, and the tradeoff between air density and air temperature set the cruising altitude to ~35,000 feet. They knew they didn't know enough to be able to build a supersonic plane, so that set the top speed at just under mach 1 at 35,000 feet. They wanted to carry 2-3 times as many passengers as the 707 which set the payload and the all up weight. It needed to go slow enough to land safely at typical airport altitudes, which set the wing loading and given the weight the wing area. It needed to be as efficient as possible which meant a high aspect ratio, but given the required wing area and the available engineering capability for wing spars and aluminum construction that set the wing span. It was hard engineering tradeoffs like that which then set a whole bunch of aviation standards. Runway lengths, terminal and jetway heights, landing approach speeds - all those types of "standards" which still exist today in airports around the globe, are heavily influenced by the 747 and it's design parameters. Cessna 172s flying into international airports have to fly their landing approach way faster than usual for that type of plane because _everybody_ flies approaches at 747 speeds. That is not today's Boeing.

dghlsakjg 1y ago
> Cessna 172s flying into international airports have to fly their landing approach way faster than usual for that type of plane because _everybody_ flies approaches at 747 speeds. This isn't even close to true. https://en.wikipedia.org/wiki/Aircraft_approach_category https://en.wikipedia.org/wiki/Aircraft_approach_category. Cessnas approach at less than half the speed of 747s. The safe maximum cruising speed is 20-30 kts short of a 747 approach speed. You would have to be willing to risk your airplane and your life to get a Cessna up to the approach speed of a 747. My experience landing Cessnas and other light aircraft at airfields where they land the big boys (including busy international ones) is that you approach and land at the speeds that the aircraft you are flying is designed for (which, btw, ATC and the FAA don’t give two shits if you are an international airport, the rules are the same everywhere in the US. I am licensed and have flown in other countries, and it varies ever so slightly, but not in the direction you are implying). I have had controllers ask me to keep speed up for spacing, but they aren't expecting miracles, they know that you simply can't get a Cessna to go above a certain speed. The rest of your comment also has some dubious claims. I suspect that the top speed was set just below mach 1, not because Boeing had no engineering knowledge about supersonic flight, but because fuel efficiency, and a host of other factors that make supersonic flight difficult. As a counter to that assertion I would point out that Boeing had a supersonic engineering team that started in 1952. They even designed a supersonic airliner that was never built in the 1960s. Hard to believe that they chose not to make the 747 supersonic because they lacked the experience to design an SST while they simultaneously had an SST design and supersonic research team before the 747 was conceived. The 747 was a groundbreaking airplane, but it wasn't all of the things being claimed here.
- NegativeK 1y ago
  To your point, the large airport I worked at was annoyed at small, slow aircraft landing because it jacked up the spacing and slowed down the customers who paid the vast majority of the bills. But the feds required the airport to allow it for a low (relatively) fee, so the airport could only be annoyed.
okdood64 1y ago
> That is not today's Boeing. How do you know they don't take all this into account when designing their planes?
- carabiner 1y ago
  Everything he described, mission requirements, sizing, trade studies, is taught in undergrad aerospace engineering curricula today. It's part of every new clean sheet design, civil, military, fixed wing or helo. It'd be the computer science equivalent of extolling how Windows was built with OOP and compiled programming languages on 8 mb ram. Pretty amazing if you're not familiar with the concepts but SOP if you're in the industry.
kqr 1y ago
> I have a book here somewhere You can't just say that, mention a bunch of interesting things, and not tell me the name of the book...
- hannofcart 1y ago
  Am not OP, but wondering if the book being referred to is '747: Creating the World's First Jumbo Jet' by Joe Sutter. Sutter was one of the people who led the design of 747.
mattmaroon 1y ago
To be fair, they did not operate in today’s world. The airlines they sold to back then before deregulation had government-guaranteed profits and so were much less focused on cost cutting than in today’s deregulated environment. For decades after deregulation the total net profit of all airlines was negative. (Might still be, I’m not sure.) The industry got really cost competitive, and so the planes they purchased had to as well.
insane_dreamer 1y ago
That's because Boeing is primarily a defense contractor these days.

dghlsakjg 1y ago

> Cessna 172s flying into international airports have to fly their landing approach way faster than usual for that type of plane because _everybody_ flies approaches at 747 speeds. This isn't even close to true. https://en.wikipedia.org/wiki/Aircraft_approach_category https://en.wikipedia.org/wiki/Aircraft_approach_category. Cessnas approach at less than half the speed of 747s. The safe maximum cruising speed is 20-30 kts short of a 747 approach speed. You would have to be willing to risk your airplane and your life to get a Cessna up to the approach speed of a 747. My experience landing Cessnas and other light aircraft at airfields where they land the big boys (including busy international ones) is that you approach and land at the speeds that the aircraft you are flying is designed for (which, btw, ATC and the FAA don’t give two shits if you are an international airport, the rules are the same everywhere in the US. I am licensed and have flown in other countries, and it varies ever so slightly, but not in the direction you are implying). I have had controllers ask me to keep speed up for spacing, but they aren't expecting miracles, they know that you simply can't get a Cessna to go above a certain speed. The rest of your comment also has some dubious claims. I suspect that the top speed was set just below mach 1, not because Boeing had no engineering knowledge about supersonic flight, but because fuel efficiency, and a host of other factors that make supersonic flight difficult. As a counter to that assertion I would point out that Boeing had a supersonic engineering team that started in 1952. They even designed a supersonic airliner that was never built in the 1960s. Hard to believe that they chose not to make the 747 supersonic because they lacked the experience to design an SST while they simultaneously had an SST design and supersonic research team before the 747 was conceived. The 747 was a groundbreaking airplane, but it wasn't all of the things being claimed here.

NegativeK 1y ago
To your point, the large airport I worked at was annoyed at small, slow aircraft landing because it jacked up the spacing and slowed down the customers who paid the vast majority of the bills. But the feds required the airport to allow it for a low (relatively) fee, so the airport could only be annoyed.

okdood64 1y ago

> That is not today's Boeing. How do you know they don't take all this into account when designing their planes?

carabiner 1y ago
Everything he described, mission requirements, sizing, trade studies, is taught in undergrad aerospace engineering curricula today. It's part of every new clean sheet design, civil, military, fixed wing or helo. It'd be the computer science equivalent of extolling how Windows was built with OOP and compiled programming languages on 8 mb ram. Pretty amazing if you're not familiar with the concepts but SOP if you're in the industry.

kqr 1y ago

> I have a book here somewhere You can't just say that, mention a bunch of interesting things, and not tell me the name of the book...

hannofcart 1y ago
Am not OP, but wondering if the book being referred to is '747: Creating the World's First Jumbo Jet' by Joe Sutter. Sutter was one of the people who led the design of 747.

mattmaroon 1y ago

To be fair, they did not operate in today’s world. The airlines they sold to back then before deregulation had government-guaranteed profits and so were much less focused on cost cutting than in today’s deregulated environment. For decades after deregulation the total net profit of all airlines was negative. (Might still be, I’m not sure.) The industry got really cost competitive, and so the planes they purchased had to as well.

insane_dreamer 1y ago

That's because Boeing is primarily a defense contractor these days.