Saw Concorde take off a few times, once from a A320 told to wait while the lady passed by.
Each time the noise was incredible. It was not only the boom which caused noise problems.
Having three afterburners in a civilian airport will restrict the times the plane will be able to take off and land, and I do not see the billionaire owners schlepping off to desert airports to start their trips…
Very interesting, noted the pilot is not wearing gloves/nomex, which I guess is testament to expected level of safety. Also, the standby instrument is a GRT Avionics Mini; great to see they’re using small companies that make great gear!
I was at a formal critique of an F111 check ride by a standards puke and all went well until the evaluator mentioned that I didn’t wear my nomex gloves during the flight. The visiting General attending the debrief asked me why I didn’t wear them. In my best Robin Olds mode I replied that I don’t wear gloves when flying or making love, Sir. And then I pointed out that wearing gloves was an air training command thing only. It didn’t go too well after that. The desk jockeys hate a smart ass pilot.
The prospect of yet another domestic supersonic aircraft brings back memories of my youth as an air traffic controller (Bos ARTCC), controlling aircraft (nonradar) over Nantucket, and with a mix of climbing/ descending TransAtlantic east/west traffic crossing with Bermuda/Miami north/southbound traffic;
HORRORS!
here comes Concord out of JFK, climbing to 22,000, practically demanding an immediate climb to 43,000 or it would burn so much fuel that it would have to return to JFK!
Beautiful video. But since the Concorde flew for several years, I’m not sure of this reinvention of a similar machine. Guess they know. Also, that page of checklist fluttering would drive me crazy as a distraction.
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I flew on the Concorde once, probably late summer 1981. I remember the fighter plane like takeoff. Once we left the ground, the pilot must have banked to almost 45 degrees probably for noise abatement. Otherwise, a smooth flight with an excellent meal. Before closed off cockpits so you could stand behind the pilots. Tight space wise. Hit Mach 2.0. Do not remember the altitude.
I doubt Boom plans afterburners, rather that’s one of the reasons they switched to four engines.
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Progress, but 0.82 is the cruising speed of many modern airliners.
Boom is working up to 1.0 in steps, checking data after each flight.
Boom claimed modern fabrication methods facilitate lower costs.
What fluttering are you talking about? (XB-1 has flutter testing gear, as any new airplane does.)
Not the airplane. I’m talking about the paper page of the checklist in his lap…
I was responding to Jon P’s comment; didn’t realize the new engines have no reheat. The R-R involvement sounded promising and lent credibility but apparently wasn’t a priority for them. Still, you’d think they’d go with an existing engine vs developing a new design.
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Using the camera is an interesting solution to the high AOA approach. Wonder why they didn’t do that with Concorde. Sure is a lot simpler than dropping the nose.
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Apparently existing suppliers were not willing to commit to an engine for supersonic transport aircraft, takes investment.
So instead Boom is obtaining investment itself and put together a consortium of experienced engine parts makers and assemblers. I don’t remember where the design expertise is to come from. Standard Aero has several decades of overhaul experience, including Allison turboprops and probably turbojets from fighter aircraft.
Boom certainly has morphed its design from their first notions.
But disappointingly only plans M1.7 for the airliner, whereas Concorde was 2.07 IIRC limited by temperature of aluminum skin even painted white, Boom wanted to go a bit further to an inflection point in drag. I hope they take the XB-1 demonstrator to that speed.
I wish development would be on stuff that would help us, like big fat airliners that had nice wide comfortable seats. The development on “extreme” aircraft like electric and supersonic don’t seem to really address the crappiness of modern air travel.
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Synthetic vision may not have been ready, if even thought of.
Afterburners are hard on engines, I understand, and heavy.
Water injection has been used, also hard on engines. IIRC on B-52s and even on a few B747s - one record weight takeoff from BFI consumed 6,000 lbs of water and fuel in the takeoff.
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While another supersonic startup does not fly far.
Supersonic flight startup Exosonic closes down after running out of funds - AeroTime
Did fly a small scale UAV.
Note US military has been giving supersonic startups some money, to advance the industry in general as products may have military use.
It’s the fuel flow, not so much engine life, that is the major drawback of augmentors/afterburners. The core hardly notices whether the augmentor is in operation or not, but everything aft of it does, especially the nozzle. Added heat, loads, vibration, and thermal cycles. The fuel flow though, is astronomical, much more than the core’s fuel flow. Of course the other issue is that augmented commercial engines are not currently in production, and the standards military engines are designed to are not suitable for certified commercial use. Stress margins and lifing requirements, for instance, are more rigorous for commercial engines.
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Not in a properly designed engine. Just as in the core combustors, fuel burning creates increased volume that is converted to velocity by the divergent nozzle, with no pressure rise. The highest pressure still is just past the last stage of the HP compressor.
Absolutely right AJ. If airliners flew 30-50 Kts slower due to a comfortable, wide cabin with decent seats and good legroom there would be a good market as the flight would now be something to anticipate in good terms and not in a horrendous prospect of several hours of overcrowding and crammed seating. This wonderful idea of supersonic passenger travel is so long past public acceptance that any corporation that enters the public domain will be socially tarred and feathered together with their corporate profile. A really bad avenue to follow in social, political and economic terms.
Not necessarily, in modern engines, but the engineering answer is always “it depends”. There are different power ratings in and out of augmentor operation and different core conditions to suit. Maximum continuous, maximum (duration limited), maximum with no augmentor… however named all would be defined by the manufacturer. At a duration limited or overall maximum power setting you would necessarily see higher core (typically Turbine Inlet Temperature is the limiting factor) temperatures than at continuous power, even if the engine speeds are the same, so that would be the core “working harder” in afterburner, but that condition of working harder is not necessary for all augmentor operation. Typically there will be a minimum engine speed required for augmentor operation which depends on the operating conditions but the EPR and temperatures would be managed by the engine control systems using fuel flow schedules, nozzle geometry, bleed control, bypass ratio control. There’s a lot at play. The root result is the same though, with augmentor in operation specific fuel consumption will skyrocket, so if you can go supersonic without it, that is always going to be preferable.