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The potentially revolutionary Celera 500L aircraft

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51–60 of 252 posts

Re: The potentially revolutionary Celera 500L aircraft

#51
post #9

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

I've seen similar concepts that cover the walls with hi-res lcd to simulate sky & landscape

It's frightening to think what the ultra low cost airlines would do with such video walls. I doubt it would involve showing the passing landscape but instead would be advertisements the entire flight.

Re: The potentially revolutionary Celera 500L aircraft

#53
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

Read the many reasons below, but one big one not named is that auto engines are not designed to be operated at near peak power constantly.

Auto engines are severely derated for use in airplanes, and then all of the advantage is gone.

Re: The potentially revolutionary Celera 500L aircraft

#54
post #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.…

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Re: The potentially revolutionary Celera 500L aircraft

#55
This is super neat. Wish them the best of luck trying to get this commercialized!

One thing which was a bit surprising was actually how small the whole craft is. Scroll down the page and they show a human for scale. Looks like you can barely stand up in the center of it. But I’m sure as a private craft they will come up with some incredible interior designs nonetheless.

Re: The potentially revolutionary Celera 500L aircraft

#56
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 q…

But you can do it the other way around, resulting in the M4 Sherman. :-)

Re: The potentially revolutionary Celera 500L aircraft

#57
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

Some do, but not many

http://www.epi-eng.com/aircraft_engine_products/big-block_62...

Re: The potentially revolutionary Celera 500L aircraft

#58
post #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.…

Definitely some extraodinary claims that will require extraordinary evidence to prove. Especially getting 20+ mpg for 4500 miles, while flying at 450mph, which is near the top end of what piston/propeller aircraft are capable of. For reference, the P51 (one of the fastest fighters of WWII) had a comparable top speed. The Piaggio Avanti [0] has a somewhat similar design and top speed (460 high speed cruise), but has twin turboprops and a far shorter range and far lower claimed mpg.

[0] https://en.wikipedia.org/wiki/Piaggio_P.180_Avanti

Re: The potentially revolutionary Celera 500L aircraft

#60
post #43

Earlier quoted context omitted.

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.

V* engines share a common crankshaft with both banks, that's the V part. Please cite any specific V12 aircraft engine that can have one bank of cylinders shut down. I don't believe one exists.
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