6 ms·

>Especially getting 20+ mpg for 4500 miles, while flying at 450mph That's not what they're claiming though. They're claiming that: 1. 20+ mpg 2. maximum spee

by desdiv 6y ago

>Especially getting 20+ mpg for 4500 miles, while flying at 450mph That's not what they're claiming though. They're claiming that: 1. 20+ mpg 2. maximum speed of 450 mph 3. range of 4500 miles are possible individually, not that 1+2+3 are possible all at the same time.

aidenn0 6y ago
TFA did not say maximum speed 450mph, it said "maximum cruising speed of at least 450mph" Still doesn't mean it gets 18-25mpg at 450. If it can realistically do half of 4500 miles at 450mph, there are a lot of interesting routes (Gets you as far as Tel-Aviv from London, Boston to Phoenix, or Los Angeles to Miami). Using that completely-pulled-out-of-my-ass number of half the range at 450, and assuming quadratic drag, the full range would be at about 300mph, so a roughly 12 hour flight from New York to London at a cost of $5k.
- qzw 6y ago
  $5k plus pilots (I’d want two for a transatlantic flight). And you’d still be stuck inside a very small space for 12 hours, with what’s likely to be a porta-potty level lavatory and minimalist galley. Oh, and a single piston engine, which is less reliable than turbines, over a lot of very cold water. Not sure that would be the best use case for this plane.
  - anovikov 6y ago
    Well, the size of aircraft certainly allows for fully enclosed, proper lavatory. CJ3 used for size comparison, has one.
  - kristopolous 6y ago
    Everything deserves to have a Version 1.0 I have high hopes for the future efforts
  - dzhiurgis 6y ago
    Plus airports, airspace, immigration, depreciation, insurance. So more like 20k.
  - aidenn0 6y ago
    12 hours transatlantic is probably worse than coach (or premium coach at least) transatlantic in 7 hours for most cases. With these specs (which are completely fictional at this point), it's the size and cost of a light-jet with the speed and range of a mid-sized jet, which is a under-served niche with the increasing numbers of people in the "very wealthy, but not quite embarassingly wealthy"
  - nradov 6y ago
    The single engine is a concern. Something like Garmin Autonomí might eventually allow for single pilot flights while maintaining a reasonable level of safety. https://www.garmin.com/en-US/autonomi/ https://www.garmin.com/en-US/autonomi/
qzw 6y ago
Sure, there are all kinds of trade offs between speed, range, useful load, altitude, burn rate, etc. But it’s really the combination of 450, 4500, and 20+ that would make this plane revolutionary. Otherwise it wouldn’t be all that interesting. And if we are to take seriously their claim of competing with commercial aviation, then it would really have to perform pretty close to all three of those numbers at the same time to even have a chance. Edit: just to add a few numbers from the back of my napkin. To go 4500 miles, it would probably need to do 20mpg anyway. That’s 225 gallons of fuel. JetA is 6.7lb/gl, so ~1500lb. Not sure a small plane could carry a whole lot more than that without giving up all the useful load. And if it can only cruise at ~300mph in order to go 4500 miles, then we’re looking at a 15-hour flight in a pretty confined space with likely fairly basic amenities. It’s not exactly bringing back the glamour of aviation.
- justinclift 6y ago
  Well, from London to New York is apparently about 3500 miles, and a 15 hour journey for that sounds reasonable.
  - cerebellum42 6y ago
    A single engine plane is most likely not going to be used for ocean crossings regularly, for safety reasons, even if it is technically capable of it. Additionally, I'm not sure it has enough spare fuel reserves to make the trip with enough margin for error or unforeseen circumstances.
    - VBprogrammer 6y ago
      Single engine aircraft with a range of around 800 miles are regularly ferried across the Atlantic. Now, I'm not for a minute suggesting that this is an everyday pleasure flight, it's something which takes planning, preparation and additional equipment. However, all I'm pointing out is that range would be the least of your problems if any of the claims prove true. If you are interested this site gives a good overview of the routes and the legs involved http://220kts.com/ferry-flights/atlantic-ferry-routes.html http://220kts.com/ferry-flights/atlantic-ferry-routes.html

by desdiv 6y ago

aidenn0 6y ago

TFA did not say maximum speed 450mph, it said "maximum cruising speed of at least 450mph" Still doesn't mean it gets 18-25mpg at 450. If it can realistically do half of 4500 miles at 450mph, there are a lot of interesting routes (Gets you as far as Tel-Aviv from London, Boston to Phoenix, or Los Angeles to Miami). Using that completely-pulled-out-of-my-ass number of half the range at 450, and assuming quadratic drag, the full range would be at about 300mph, so a roughly 12 hour flight from New York to London at a cost of $5k.

qzw 6y ago
$5k plus pilots (I’d want two for a transatlantic flight). And you’d still be stuck inside a very small space for 12 hours, with what’s likely to be a porta-potty level lavatory and minimalist galley. Oh, and a single piston engine, which is less reliable than turbines, over a lot of very cold water. Not sure that would be the best use case for this plane.
- anovikov 6y ago
  Well, the size of aircraft certainly allows for fully enclosed, proper lavatory. CJ3 used for size comparison, has one.
- kristopolous 6y ago
  Everything deserves to have a Version 1.0 I have high hopes for the future efforts
- dzhiurgis 6y ago
  Plus airports, airspace, immigration, depreciation, insurance. So more like 20k.
- aidenn0 6y ago
  12 hours transatlantic is probably worse than coach (or premium coach at least) transatlantic in 7 hours for most cases. With these specs (which are completely fictional at this point), it's the size and cost of a light-jet with the speed and range of a mid-sized jet, which is a under-served niche with the increasing numbers of people in the "very wealthy, but not quite embarassingly wealthy"
- nradov 6y ago
  The single engine is a concern. Something like Garmin Autonomí might eventually allow for single pilot flights while maintaining a reasonable level of safety. https://www.garmin.com/en-US/autonomi/ https://www.garmin.com/en-US/autonomi/

qzw 6y ago

Sure, there are all kinds of trade offs between speed, range, useful load, altitude, burn rate, etc. But it’s really the combination of 450, 4500, and 20+ that would make this plane revolutionary. Otherwise it wouldn’t be all that interesting. And if we are to take seriously their claim of competing with commercial aviation, then it would really have to perform pretty close to all three of those numbers at the same time to even have a chance. Edit: just to add a few numbers from the back of my napkin. To go 4500 miles, it would probably need to do 20mpg anyway. That’s 225 gallons of fuel. JetA is 6.7lb/gl, so ~1500lb. Not sure a small plane could carry a whole lot more than that without giving up all the useful load. And if it can only cruise at ~300mph in order to go 4500 miles, then we’re looking at a 15-hour flight in a pretty confined space with likely fairly basic amenities. It’s not exactly bringing back the glamour of aviation.

justinclift 6y ago
Well, from London to New York is apparently about 3500 miles, and a 15 hour journey for that sounds reasonable.
- cerebellum42 6y ago
  A single engine plane is most likely not going to be used for ocean crossings regularly, for safety reasons, even if it is technically capable of it. Additionally, I'm not sure it has enough spare fuel reserves to make the trip with enough margin for error or unforeseen circumstances.
  - VBprogrammer 6y ago
    Single engine aircraft with a range of around 800 miles are regularly ferried across the Atlantic. Now, I'm not for a minute suggesting that this is an everyday pleasure flight, it's something which takes planning, preparation and additional equipment. However, all I'm pointing out is that range would be the least of your problems if any of the claims prove true. If you are interested this site gives a good overview of the routes and the legs involved http://220kts.com/ferry-flights/atlantic-ferry-routes.html http://220kts.com/ferry-flights/atlantic-ferry-routes.html