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The potentially revolutionary Celera 500L aircraft

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Re: The potentially revolutionary Celera 500L aircraft

#41
post #14

Earlier quoted context omitted.

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

Wow, this is a literal nightmare for flight anxiety sufferers.

Not being sarcastic, my claustrophobia kicked in and my breathing literally became a bit heavier as I imagined sitting in a metal tube without windows. Had never considered how psychologically important windows are, before.

Re: The potentially revolutionary Celera 500L aircraft

#42
post #14

Earlier quoted context omitted.

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

Commercial airlines have a future? In the near future, only the wealthiest people will be able to fly, and good luck denying them windows. As for everyone else, Im thinking theyre taking the windows out because they are planning to convert over to cargo flights or something.

Why do you think that?

Re: The potentially revolutionary Celera 500L aircraft

#43

Earlier quoted context omitted.

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

Nothing is inherently bad but diesels tend to be heavier for the power they make. And there's a fairly well understood weight vs reliability tradeoff. Light an unreliable is bad for airplanes and so is heavy and reliable. You want light and reliable, ideally.

It is a V12. Historical military V12s had a feature of two bank redundancy. One row of 6 cylinders can be shut down along with its pumps, cooling, etc.

And I have a big suspicion that they use two of these engines inside.

Re: The potentially revolutionary Celera 500L aircraft

#44
post #14

Earlier quoted context omitted.

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

Wow, this is a literal nightmare for flight anxiety sufferers.

Only if they don't replace them with even larger digital "windows." There's also been work towards electronic windows in aircraft.

Re: The potentially revolutionary Celera 500L aircraft

#45
For some perspective, the Scaled Composites Catbird (powered by a 210-hp V6) achieved just over 20 mpg at 200 mph with close to 1000 lbs of payload (it could carry a pilot and four passengers) in the late '80s and early '90s.

Amateur-built experimentals have achieved upwards of 50 mpg in realistic flying conditions, but they generally tended to be tandem-seat designs with minimal frontal area and low-powered engines.

More recently, the Pipistrel Taurus G4 (a highly modified sailplane with an electric motor between twin fuselages, designed to carry a pilot and three passengers) achieved just over 100 mpg at ~107 mph.

I eagerly await proof that the Celera--a significantly larger, heavier, and faster aircraft than Rutan's Catbird--actually achieves similar fuel economy. If true, it would be a pretty incredible leap for an industry that's been largely stagnant for decades, but these sorts of claims have a long history of being either sadly mistaken or outright fraudulent.

Re: The potentially revolutionary Celera 500L aircraft

#46
post #29

Is there a reason why small aircraft don't just use a car engine (with some appropriate gearing I guess)? Those have had so much R&D in them and they're pretty much as efficient as you can get - plus much easier to maintain and repair

Automotive engines are designed to produce power at a wide range of operating speeds, at the detriment of peak power output and peak efficiency. Aircraft engines can take advantage of the fact that they will be operating at a single RPM range for most of their life, which allows you to optimize every single aspect of the system for that speed. Aircraft engines also have much, much higher reliability, lifecycle, and quality control requirements than automotive engines.

For these reasons and a few others, you would basically end up redoing most of the engineering work on an automotive engine to repurpose it for aerospace applications, thus negating the savings of reusing the existing design.

Re: The potentially revolutionary Celera 500L aircraft

#47

It seems to require a pretty seriously long runway to take off. On a warm day, we’re talking international airport length runway. While pistons are cheaper than turbines, that’s because almost all of the approved pistons on the market use 1940s or earlier technology. They are very, very, very simple machines. They are still extremely expensive. This engine is very complicated, even for an automotive engine. It’s got…

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

Re: The potentially revolutionary Celera 500L aircraft

#48
post #38

It seems to require a pretty seriously long runway to take off. On a warm day, we’re talking international airport length runway. While pistons are cheaper than turbines, that’s because almost all of the approved pistons on the market use 1940s or earlier technology. They are very, very, very simple machines. They are still extremely expensive. This engine is very complicated, even for an automotive engine. It’s got…

Since this plane is intended to compete with other business jets, don't owners of typical business jets mostly travel to (international) airports with long enough runways anyway?

Half the point of a business jet is flying to more convenient (but smaller) airports.

Re: The potentially revolutionary Celera 500L aircraft

#49
post #30

It seems a bit dishonest to compare it to a jet, when the obvious competition is a single engine Turboprop like a TBM or PC-12. On paper it beats those aircraft, but by a far less impressive margin when you consider engine TBO, which is currently 1250 hrs on the EASA cert. With the inherent unreliablilty of piston engines, a PT-6 might look more appealing. I'd love to see this aircraft come to market, but I fear it m…

Big guesstion, do they have one, or two engines? A combiner gearbox does not fare well in aviation, as history show.

I have a hard time believing they can get to such speed with just 500hp.

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