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Hi - I'm Blake, Founder/CEO at Boom. After watching no tangible progress in supersonics since Concorde was shut down, I started Boom because I want supersonic flight in our lifetime. Not just as a private jet, but something most anyone can afford to fly. Will try to answer as many questions here as I can.
didn't YC also invest in a nuclear startup? how's that going?
UPower less so.
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specially if the F-18 pilot is making sure that every bug smasher from Mount Whitney to the Mojave knows what true speed is. I've read and re-read that story so many times, each reading results in a fresh batch of goosebumps. I'd love to read the book (Sled Driver, I think?), but it is over $500 on Amazon. I wish they either ordered another print OR published as an ebook.
Yikes! I have two copies, having thought that I'd lost mine years ago -- bought a new one -- then found the original again.
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Very skeptical this little company can go all the way with this. Look at how hard it is to get a new automobile company up and running. Tesla almost went completely bankrupt more than once. I do think there is a need and market for faster than sound air travel. We have the technology to even minimize the sonic booms for over land travel. Still, it would take an enormous amount of capital to get a new company up and r…
I am not saying this is easy, but what they need to do is build one airplane, and get it to fly back and forth. That is nothing like the scalability and repeated reliability that building thousands of car is asking for. I know several people (starting by my brother) who build their own plane (granted, it was a two-seater several several times louder than a grass-mower and seemingly slower, but you get the idea). One…
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"Since the aircraft can do nearly 3X as many trips in the same time" Isn't that a bit optimistic? I would think it's closer to 2X. 2.6 times the airspeed, but why would turnaround time at the airport be any lower than for a comparably modern 'slow' airplane? For example, 6 hour flight plus 1 hour turnaround time versus 2.3 hours plus 1 hour turnaround time is more or less a factor of 2. For longer flights, the ratio…
Boarding should be faster, since it's only 40 seats and, ostensibly, roomier.
Hi - I'm Blake, Founder/CEO at Boom. After watching no tangible progress in supersonics since Concorde was shut down, I started Boom because I want supersonic flight in our lifetime. Not just as a private jet, but something most anyone can afford to fly. Will try to answer as many questions here as I can.
What about CO2 emissions?
Adding CO2 reduction engineering to an already difficult project means less resources available to actually get the thing to work.
Imagine if The Apollo program had to worry about CO2 emissions on top of just trying to get a rocket to launch.
You also could argue some economy of scale efficiencies. If one flight on this plane caused just 3 passengers to forego a private jet trip for the same distance, you'd save 3 private jet's worth of flights. Given the time savings, this project would certainly disrupt a segment of the private jet market.
A 777 burns 1680 gallons per hour with 365 maximum passengers. A Gulfstream G650 burns about 865 gallons per hour.. holding a max of 18 passengers. So the G650 is burning 48 gallons per hour, per passenger while the 777 is doing 4.6 gallons per hour per passenger. We're assuming fully loaded for comparison but we all know that a G650 is rarely flying a 18 pax capacity, generally it's in an 11 seat configuration.
So as you can see, even if the fuel efficiency were half of a 777, it would still be a massive efficiency compared to a G650 and thus a net gain for those concerned about CO2.
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To be fair to our electric friends, electric motors are >90% efficient while turbofans top out at somewhere near 35% efficiency (as far as I can find).. So what appears to be a 40:1 advantage to kerosene is more like a 15:1 advantage -- substantial but much more accessible with ongoing battery improvements. Though as another commenter mentioned, fuel planes do definitely benefit from shedding weight the entire time t…
A jet engine (e.g. turbofan) relies on combustion in the engine in order to function. The ignition of the fuel from within the engine is key… it is not just there to just create energy to drive rotational force. You would you use an electric motor on a plane without going back to what is essentially a propeller design?
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And yet Musk claims transcontinental range (NY-LA) would be possible with 400 Wh/kg batteries and mid-70% battery mass fraction. http://www.aviation.com/general-aviation/elon-musk-toying-de...
A 70% battery mass fraction seems like a huge engineering challenge for an aircraft. I did a quick calculation of fuel mass fraction for the various Boeing 777 models [0] which ranged from ~13% to ~36%. Not saying it's impossible. Just hard. [0] https://en.wikipedia.org/wiki/Boeing_777#Specifications
Building an economically viable mass-market aircraft with a 70% mass fraction might be another question, but if we're just talking about the engineering challenge of building it at all I don't think that's hard?