The Concorde relied on an afterburner to achieve supersonic flight, so it burned a ton of fuel. It also could not go supersonic over land because its sonic booms were too loud. This mean that flights could only go over the ocean, and they were expensive due to fuel costs. Boom's goal is to reduce the sound of their sonic booms 30x and eliminate the need of afterburners.
No. I don't think that's correct. The Concorde used its afterburners during take off and to get through the transonic region, where the drag is very heavy. Once you've gone past that the drag drops. At that point the Concorde can turn off the after burners.
IIRC Concorde could super cruise a Mach 2 which is unmatched. It would also flight supersonic for most of its journey which is also presented unprecedented difficulties.
Legend says the Tu-144 used afterburners the whole time while supersonic, but, then, it seems five units have engines without afterburners (RD-36-51's replacing the Kuznetsov NK-144 used in most of the fleet).
I wonder what was the noise level in those late models.
Not really, that's like saying "they relied on closing the doors to the aircraft to achieve supersonic flight". Both happened, but aren't related if I'm reading the comments correctly.
That's a really dumb response. Yes, it relies on closing the doors to achieve supersonic flight too.
The Boom plane doesn't rely on afterburners at any point in the trajectory to achieve supersonic flight. So yes, you would be reading the comments incorrectly.
Boom is not currently flying their intended engines, the Symphony, which does not exist yet. (1) The XB-1 is flying with J85's just like a T-38 has, and just like a T-38 it can go supersonic with afterburners. If the Symphony is able to meet its design goals, it will not need afterburners for any part of flight. How much they will be able to deliver on that remains the biggest open technical question for Boom. (2)
1: Well, their Plan B intended engines. Their Plan A was that one of the Big 3- RR, PW, GE- would make engines for them, but none were interested in taking the risk that a difficult engine could be designed and built in enough volume to make the investment back.
2: Their biggest legal question is over-land supersonic regulations. Their biggest economics question- and probably the biggest and most important of all of them- is how much will people pay for civil supersonic?
Do we know how much more it's likely to cost? I could easily see people paying 1.5x - 2x.
Anything beyond 2x I imagine would start to price out the average person and anything beyond 5x would probably price out the vast majority of potential customers.
People pay more than that for domestic first class, which doesn’t even have lay-flat seats. $2,500 or even $5k for a New York <> San Francisco 2-hour flight would absolutely sell.
A number of US carriers offer lay-flat seats for at least some of their coast-to-coast domestic flights. UA has over a half dozen Dreamliners flying back and forth daily, all with Polaris cabins. I know AA and Delta have routes with them, too. I agree, a two-hour flight time would be better!
Their business model for a long time has theorized that they can deliver an operating cost that would allow airlines to offer tickets at roughly current business class ticket costs, which would be a fraction of Concorde ticket prices expressed in current dollars.
I don't know if those theorized efficiencies will be delivered (a lot depends on that engine) or if airlines will price tickets at that level. But it's the theory so far.
When the production engine exists in physical form, we can absolutely discuss its capabilities. The XB-1 demonstrator is, using afterburner to get to speed, demonstrating other design features intended to keep the noise down.
The original plan was a commercial partner for the engines, but the big three - Rolls-Royce, Pratt & Whitney and General Electric - turned them down. It's one of the biggest remaining question marks in the entire project.
> Supercruise is sustained supersonic flight of a supersonic aircraft without using afterburner.
> Concorde routinely supercruised most of the way over the Atlantic
Real question: How many in-production/operation engines in world can fly supersonic without afterburners? I think it is only a handful, all insanely expensive and backed with squillions of dollars of gov't/military money. And, the maintenance cycle must be out of this world expensive.
