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desdiv

>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.

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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.

I'd take any sleeping pod any time, even if I had to bring my own sandwiches, piss into a bottle and have 0 entertainment than sit for more than 8 hours in economy flight of any current airline.

I'd similarly prefer a low-headroom bunk bed. I think the problem is bracing for take-off and landing and evacuations.

Well, from London to New York is apparently about 3500 miles, and a 15 hour journey for that sounds reasonable.

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.

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

Ferrying is not a paying passenger flight, correct?

How would single-engine craft comply with ETOPS - the relevant standard for passenger flights, or equivalent?

https://en.wikipedia.org/wiki/ETOPS

https://aerosavvy.com/etops/

The short answer is they don't and it's pointless to ask about it since these flights are conducted under part 91 for private aviation. There is almost no charter or scheduled flights allowed on single engine aircraft in Europe and the few that do exist are using single engine turbines on an exemption (the exemption is based on the fact turbines have a demonstrated order of magnitude better reliability).

This has changed relatively recently (2017) in the EASA rules and single-engine IFR charter flying is possible without special exemptions as long as the engine has demonstrated good reliability (basically it means turbine engines).

> There is almost no charter or scheduled flights allowed on single engine aircraft in Europe

So, without new regulation, this aircraft will not carry out "charter or scheduled flights in Europe" ?

This airplane has a "2 in 1" engine. Two separate engines running on one physical engine block. So there is some engine redundancy.

yes but that really only matters if the second "engine" produces enough power for maneuvering if the first one fails. Plus, there is still mechanical interconnectedness so it isn't truly redundant. That said it is likely far safer than a traditional twin, the axiom with those is if you lose one engine the second will fly you all the way to the scene of the crash.

There's a link to the motor manufacturer in the article (but it's down right now). As I recall the two motors are identical with no common parts other than the engine block.

Especially if you're saving time at either end by skipping all the Heathrow delays (long security checks, baggage check, etc)

People who fly privately don't need to go through any checks ?

Not the ones protecting expensive commerical planes.

And here I was thinking it was to protect the passengers.

No need to protect the passengers if there aren't any other people on your flight!

Only if it has cryosleep chambers on-board.

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.

$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.

Plus airports, airspace, immigration, depreciation, insurance. So more like 20k.

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"

Well, the size of aircraft certainly allows for fully enclosed, proper lavatory. CJ3 used for size comparison, has one.

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/

Everything deserves to have a Version 1.0

I have high hopes for the future efforts

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