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The potentially revolutionary Celera 500L aircraft

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Re: The potentially revolutionary Celera 500L aircraft

#151

Post by rad_gruchalski »

Animats wrote: 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…

Interesting trivia: the CTO of RED and part of the staff used to work for and build Toyota F1 engines in Cologne.

Re: The potentially revolutionary Celera 500L aircraft

#152

Post by justinclift »

qzw wrote: post #129
desdiv wrote: 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…

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

Re: The potentially revolutionary Celera 500L aircraft

#153

Post by badestrand »

alfalfasprout wrote: post #61

It's still a GA aircraft though... so you still have to deal with all the BS. If you don't own it yourself then you need to pay a pilot (though with the recent downturn there's no shortage of pilots). There is absolutely no way many people will try and get their pilot's license. The FAA written test for a PPL may be easy compared to IR but it's still not a walk in the park. The checkrides are very strict nowadays too…

Is there automated flying on the horizon? Seems to me that it should be a lot simpler than for cars and would make operating so much simpler and more cost effective.

Re: The potentially revolutionary Celera 500L aircraft

#154

Post by marvin »

scarier wrote: 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.…

Stands to reason that a modified glider will achieve the best efficiency characteristics. That is after all, practically speaking, the raison d'ètre for sailplanes.

Re: The potentially revolutionary Celera 500L aircraft

#155

Post by benhurmarcel »

dmix wrote: post #102
karlkatzke wrote: post #80

Earlier quoted context omitted.

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.

Sorry for the amateur question, but why does it take longer to take off in hot places? Doesn’t heat generate lift, like in gliders crossing hilly terrain? Or is it the heat offsetting with the cooler ground that helps, so you’d need a greater amount in hot places?

Other answers already address the engine performance loss and lift loss, but about that:

> Doesn’t heat generate lift, like in gliders crossing hilly terrain?

That lift is generated by a temperature difference, not a globally high temperature. Thermals used by gliders are thermals because the air is locally hotter than the environment. If the whole environment gets warm, you don't get thermals.

Re: The potentially revolutionary Celera 500L aircraft

#156

Post by benhurmarcel »

CydeWeys wrote: post #73
alfalfasprout wrote: post #61

It's still a GA aircraft though... so you still have to deal with all the BS. If you don't own it yourself then you need to pay a pilot (though with the recent downturn there's no shortage of pilots). There is absolutely no way many people will try and get their pilot's license. The FAA written test for a PPL may be easy compared to IR but it's still not a walk in the park. The checkrides are very strict nowadays too…

I think the point is more that this kind of tech could be scaled up to make commercial airliners more fuel efficient too?

A big part of the "tech" is the engine and its turbocharger. That doesn't really scale.

Re: The potentially revolutionary Celera 500L aircraft

#157

Post by KMag »

baybal2 wrote: post #143
KMag wrote: post #121

Earlier quoted context omitted.

> Success is dependent on the gearbox. This uses a single V12 Diesel engine. The Lear Fan used dual turboshaft engines.

It is not clear yet: https://the-drive.imgix.net/https%3A%2F%2Fs3-us-west-2.amazo... And the speed figures are hard to believe for just 500hp, and an aircraft of this size. What is on the photo make me think they have 2 of them, mounted at 120 degrees.

Ahh, that makes much more sense. Upvoted.

Re: The potentially revolutionary Celera 500L aircraft

#158

Post by londons_explore »

desdiv wrote: post #103
davidgould wrote: post #60

Earlier quoted context omitted.

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.

>Please cite any specific V12 aircraft engine that can have one bank of cylinders shut down. The RED A03 Engine[0], which is what this sub-thread is about. >Two cylinder-bank redundancy concept for high safety. >Robustness and safety are incorporated into the engine design. The two 6-cylinder banks are capable of independent operation. All critical engine sub-systems are mutually-independent. [0] https://red-aircraft…

Except the crankshaft...

Oh, and any mechanical issues with pistons or valves in one side will jam the crankshaft, therefore stop the other half working...

And that crankshaft needs some kind of oil... And a pump to pressurize that oil. And if a leak forms anywhere the oil drains out and the crankshaft seizes. Pretty hard to lube one crankshaft with two redundant and isolated oil systems...

Overall, I'd call the engine 1.5x redundancy...

Re: The potentially revolutionary Celera 500L aircraft

#159

Post by magicalhippo »

littlestymaar wrote: post #145
generatorguy wrote: post #108

Earlier quoted context omitted.

When it is hot out Air is less dense so the wings don’t generate as much lift. I believe engines make less power when the air in is hotter too as there is less delta T. Something something Carnot cycle

The engine indeed makes less power, but since the air density is lower, you also have much less drag. (I know that for cars, the drag reduction dominates the power efficiency). For airplanes take-off, the lift is the issue I'd say.

As a concrete example, current Formula 1 cars reach their fastest speed at the Mexico Grand Prix, held at Autódromo Hermanos Rodríguez in Mexico City. Current race record is 372.5km/h (231.5 mph)[1].

The elevation of the track is around 2200m, and as you say the loss of drag more than compensates for the loss of engine power. Though being turbo engines helps as I understand.

[1]: https://en.wikipedia.org/wiki/List_of_Formula_One_race_recor...

Re: The potentially revolutionary Celera 500L aircraft

#160

Post by Kliment »

jacobwilliamroy wrote: post #114
romski wrote: post #35

Earlier quoted context omitted.

You can fly right now if you want to - flights are very cheap! What point are you trying to make?

You can buy a cheap ticket on an empty plane. Do the math. This is a passing thing, and airlines are either going to raise prices or go out of business.

You can buy a cheap ticket on an empty flight that then gets cancelled.
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