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The potentially revolutionary Celera 500L aircraft

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Re: The potentially revolutionary Celera 500L aircraft

#191
post #14

The idea of being stuck in a plane for hours with no windows is...odd.

This is the future of airplanes. Windows add cost and reduce the structural integrity of the plane. Commercial airlines are already removing them. https://www.bbc.com/news/business-44383220

[Off-topic] In the Mass Effect games series, Geth (a synthetic race) warships don't have windows as they are considered a structural weakness. In the game, there are some interesting conversations based on that.

Re: The potentially revolutionary Celera 500L aircraft

#192

Earlier quoted context omitted.

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

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 ?

Re: The potentially revolutionary Celera 500L aircraft

#193
post #129
post #100

Earlier quoted context omitted.

>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.

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…

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.

Re: The potentially revolutionary Celera 500L aircraft

#194
post #23

It's a Diesel. The engine is made by RED in Germany.[1] Almost the same Diesel powers the YAK-152 trainer.[2] Celera avoids the term "Diesel", but that's what it is. It runs on Diesel fuel, or JET-A, which is much the same thing. The base engine has been flying for several years. This is the turbocharged model. So it's an engine design with some flight experience. [1] https://red-aircraft.com/ [2] https://en.wikipedi…

Ok, but so what? Is there something bad about diesel engines?

BSFC as in horsepower generated per unit of fuel tends to be better in Diesel engines, but they’re heavier because the combustion events are more violent, requiring a stronger block and pistons.

Re: The potentially revolutionary Celera 500L aircraft

#195
post #137

Earlier quoted context omitted.

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,…

$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.

Re: The potentially revolutionary Celera 500L aircraft

#196

Earlier quoted context omitted.

I think this airplane is pressurized, flies very high and has a big turbocharger. And it has a diesel engine, so the MPG means a different thing - diesel is denser. It's optimized differently to the experimentals, and it's more useful commercially. Flying high avoids a lot of weather issues. You don't have to cancel flights because of weather. The drag from the streamlined shape is very low. It's just a textbook mini…

The design of the body reduces drag and acts as a mechanism for lift. https://en.wikipedia.org/wiki/Lifting_body

A lifting body sounds like you are getting something for free, but it does not really work out that way. In terms of efficiency, what matters is the overall lift/drag ratio, and so the first issue is whether shaping the fuselage for lift can be done without creating so much extra drag as to reduce the overall lift/drag ratio. In this regard, note that fuselages are long and narrow, while efficient wings are wide in span and short in chord.

A second factor is the effect of a lifting body on stability, and the cost of compensating for it. Even in the case of nominally non-lifting fuselages, they tend to produce lift at high angles of attack, and that tends to be destabilizing, producing an increasing pitch-up moment as the angle of attack increases (ordinary straight wings do too, but the effect is proportionately less, as the wing chord is considerably less than the fuselage length.) This has to be corrected with measures (typically a larger stablizer) that also create drag. Having a fuselage designed to produce lift exacerbates this problem, commensurably with the amount of lift being generated.

Modern sailplane design is a case study in the persuit of aerodynamic efficiency, at least at low speeds, and lifting bodies have not proved to be useful. The fact is that, once you are flying, you do not need more lift; what you want is less drag.

Re: The potentially revolutionary Celera 500L aircraft

#197

Earlier quoted context omitted.

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.

Re: The potentially revolutionary Celera 500L aircraft

#198
post #47

Earlier quoted context omitted.

3,300 feet in not a long runway - it means you can access ~80% of the ~5,000 runways in the US. On the the other hand A 777 needs 8,000-10,000 feet meaning it can only access https://www.cia.gov/library/publications/the-world-factbook/... https://en.wikipedia.org/wiki/Boeing_777#777-200LR

3300 feet in balanced density conditions. You’d better not bet on 3300 feet in Phoenix during the day time most of the year. Or Denver for that matter.

Aspen seems like a likely destination for this kind of craft. Is an 8000' runway at 9000' of elevation sufficient?

Re: The potentially revolutionary Celera 500L aircraft

#199
post #129

Earlier quoted context omitted.

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…

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.
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