371–380 of 531 posts
Burning more Jet-A to get less people around the world faster has got to be the most tone deaf idea this decade. I'm a pilot, I just attended Airventure, and I love the history around SR-71, Concorde and the other incredible high speed planes we've built. But this is an idea that had its time and aviation has moved on to high bypass turbofan engines, reliability, safety, fuel efficiency and reducing our environmental…
Burning more Jet-A to get less people around the world faster has got to be the most tone deaf idea this decade. I'm a pilot, I just attended Airventure, and I love the history around SR-71, Concorde and the other incredible high speed planes we've built. But this is an idea that had its time and aviation has moved on to high bypass turbofan engines, reliability, safety, fuel efficiency and reducing our environmental…
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IMHO a better title would have been: "American Airlines to buy 20 Overture aircraft from Boom Supersonic" When reading the original title, I had the impression that the company was going to be acquired by AA. Instead, it's "just" an order of 20 aircrafts. Note that this is not a new move by Boom, they played this card when raising money when they pitched at YC demo day, and they're doing it again. The problem I have…
Same. I think their timelines are too aggressive. I want to be proved wrong though!
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This isn't going to be applicable to 95+% of aviation, but for something like a flight between the US and Australia, e.g. LAX to SYD? Going from a 15h to 8h flight will be huge -- that's 30h to 15h round-trip. I'm American and visited Australia once, and realized I probably never would again, it's just too far. An Australian friend of mine here in the US only went home to see his family every few years. It just takes…
You don't need to go everywhere, really. Especially not halfway round the world for a vacation.
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ah, neat! looks like they recently switched from 3x turboprop to 4x turbofan edit: had to correlate sources to find that a bunch of popular aviation blogs got the original design wrong. was actually 3x turbofan -> 4x turbofan
why the downvotes? the original design was trying to use 3x turboprops, and i can see articles on google about them switching to 4x turbofans after the xb-1 work edit: see parent edit, i was wrong. you guys are pretty good at making someone with misinfo feel bad though
It’s the original source of the mistake that should feel bad as they’re supposed to be experts in the field.
Overture is being designed to carry 65 to 80 passengers at Mach 1.7 over water — or twice the speed of today’s fastest commercial aircraft — with a range of 4,250 nautical miles. Optimized for speed, safety and sustainability, Overture is also being designed to fly more than 600 routes around the world in as little as half the time. Flying from Miami to London in just under five hours and Los Angeles to Honolulu in t…
> over water All the imagined routes are over large bodies of water. Is it key to the functionality or intent of the aircraft in some way? Why not NYC to LAX in 3 hours?
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why the downvotes? the original design was trying to use 3x turboprops, and i can see articles on google about them switching to 4x turbofans after the xb-1 work edit: see parent edit, i was wrong. you guys are pretty good at making someone with misinfo feel bad though
You have to be mixed up; a turboprop has a propeller attached to the jet engine. No-one in their right mind would use a turboprop supersonically. It would make an insane amount of noise.
Since this is the pedant thread I feel obliged to point out that turboprops are propellers attached to gas turbine engines, not jet engines. Jet engines are gas turbine engines that produce thrust using a jet of hot exhaust gas out the back. Gas turbine engines that don't produce thrust using a jet of exhaust gas aren't jet engines; examples are turboprop engines and turboshaft engines (popular in helicopters, some tanks, etc.) Turbofan engines produce at least some of their thrust with an exhaust jet, so it's fair enough to call those jet engines. Probably the truest sort of jet engines are turbojet engines, which are no longer used for commercial aviation and only have some niche applications remaining (for instance cruise missiles.)
Then there are the "jet engines" which aren't gas turbines at all; jetskis use gasoline powered piston engines to produce thrust using a jet of water. And rockets, which don't breath air, could be called jet engines in a sense because they produce thrust using a jet of exhaust gas. But if you go around calling rocket engines "jet engines" you're going to get a lot of people correcting you by pointing out that rocket engines don't breath air. Many rocket engines do contain gas turbines though, using gas turbines to power propellant pumps, e.g. turbopumps...
And if we really want to get into the weeds, some piston powered aircraft get a small amount of thrust from their exhaust too. And some exploit the "Meredith effect", wherein air over the radiators gets heated and produces a small amount of thrust. These effects may contribute a few percentage points of the total thrust of the plane, and in truth, some turboprop configurations do this too. But >90% of the thrust is coming from the propeller, not the exhaust.
So they went from scaled down Concorde configuration : https://www.airway.com.br/wp-content/uploads/2020/10/Boom_Ov... to a very scaled down Boeing 2707-300 configuration : https://en.wikipedia.org/wiki/Boeing_2707 (that tiny fin tho...). While reducing cruise speed to 1.7 mach. I see no visible changes to deal with the sonic booms problem. So operation would be like Concorde I suppose, subsonic (or hi-subsonic) over…
And they still have not solved the problem that ultimately sunk the Concorde. Fuel costs made it unprofitable to operate whenever the price of oil went up. The small niche of customers willing to pay a significant premium in order to save some travel hours is not big enough to sustain an entire industry of specialized mechanics, parts suppliers, pilots, etc... Basically you need a critical mass of people riding these…
Going from the Concrods 3550nm range to 4250nm should help with that as it opens up several new routes and longer routes see a more significant drop in travel times.
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Right. At this point a new aircraft program is easily $15B+ of development. That kind of money is hard to come by for a new aviation company. China, Russia, and Japan have all tried breaking into the market as well without much success.
Why aren't the Chinese and Russians successful at building airliners? International politics aside, they have workable products, so why can't they break into the duopoly.
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And they still have not solved the problem that ultimately sunk the Concorde. Fuel costs made it unprofitable to operate whenever the price of oil went up. The small niche of customers willing to pay a significant premium in order to save some travel hours is not big enough to sustain an entire industry of specialized mechanics, parts suppliers, pilots, etc... Basically you need a critical mass of people riding these…
They seem to have dramatically reduced fuel consumption, but fuel wasn't the issue for the concord the limited number of viable routes where. Going from the Concrods 3550nm range to 4250nm should help with that as it opens up several new routes and longer routes see a more significant drop in travel times.