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The potentially revolutionary Celera 500L aircraft

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Re: The potentially revolutionary Celera 500L aircraft

#61

Post by alfalfasprout »

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.

So if you're paying a pilot, FBO costs (or dealing with a commercial operator of the planes), etc. at the end of the day it's never going to be as cheap as commercial airlines. This certainly would make it affordable. But not that affordable.

Re: The potentially revolutionary Celera 500L aircraft

#62

Post by Ericson2314 »

Not gonna lie, this week I've read two HN postings about dope planes for rich people (boom, now this)......and news articles detailing a crisis of austerity for the NYC subway.

It's really sad to me that we can VC these wild bets on inefficient transport for the few, meanwhile perhaps the most efficient people-mover ever devised for the many is on an entirely politically-caused death bed.

Re: The potentially revolutionary Celera 500L aircraft

#63

Post by brunooo »

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.…

Feel the same, rooting for them but website is still a bit light on actual data and a lot of startup speak, wondering how they would get that big of an improvement vs similarly shaped (Avanti EVO) or powered (DA62) aircraft.

Other question is how safe the simplicity of the shape is, no front wing / canard with presumably very variable CG, or if they’ll have to sacrifice a lot of initial specs to make it work. Also if one should feel comfortable about the only semi-redundant engine over long stretches of water.

Re: The potentially revolutionary Celera 500L aircraft

#65

Post by baybal2 »

davidgould wrote: post #60
baybal2 wrote: post #43

Earlier quoted context omitted.

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.

Of course the crankshaft is shared. It is oil, fuel, and cooling that can be shut down to prevent leaks.

Re: The potentially revolutionary Celera 500L aircraft

#66

Post by gsnedders »

jdhn wrote: post #18

I'm kind of curious as to why they went with the engine that they did instead of something based off of Chevrolet's LS engine architecture, but tuned for the unique demands of planes. Seems that they place efficiency as a high standard, and the LS series of engines are pretty efficient in terms of how much power they generate vs how much space the engine takes up.

I expect in part fuel availability: Jet-A is available at practically all airfields nowadays, and the future of Avgas is still somewhat uncertain (the majority worldwide is still leaded!).

Re: The potentially revolutionary Celera 500L aircraft

#67

Post by owenversteeg »

msandford wrote: post #39
gregschlom wrote: post #27

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.

This is far lighter and significantly different from your usual diesel, though. It's an all-aluminum design and weighs 250-300kg. Heavier (for the same power) than competing turbine engines (like, say, the ubiquitous PT6?) Sure, absolutely. Crazy heavy? Nah. The entire thing probably weighs somewhere around 2000-3000kg (veeery roughly) if I had to guess. So the extra 100kg or so isn't a total dealbreaker, if they can make it up elsewhere.

Very interesting aircraft for sure. I'm still skeptical, but hoping it works out, and rooting for them!

Some discussion on its claims to fly at 65,000 feet here: https://www.beechtalk.com/forums/viewtopic.php?f=49&t=174467...

Re: The potentially revolutionary Celera 500L aircraft

#68

Post by jasonwatkinspdx »

geokon wrote: 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

They do, though it requires some conversion to meet reliability requirements and to optimize for cruise. Over the years the Subaru boxer engines have been a popular starting point.

Re: The potentially revolutionary Celera 500L aircraft

#69

Post by scarier »

brunooo wrote: post #63
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.…

Feel the same, rooting for them but website is still a bit light on actual data and a lot of startup speak, wondering how they would get that big of an improvement vs similarly shaped (Avanti EVO) or powered (DA62) aircraft. Other question is how safe the simplicity of the shape is, no front wing / canard with presumably very variable CG, or if they’ll have to sacrifice a lot of initial specs to make it work. Also if…

The CG question is really good, but considering the very conventional tail on the prototype, I imagine it has about the same acceptable CG range as a similar passenger aircraft. The wing just looks like it's way too far back since the engine's in the back instead of the front.

Hopefully it's not intended to do regular transoceanic flights, but it should be fine for shorter crossings (e.g. Great Lakes, Mediterranean north/south, etc.).

Re: The potentially revolutionary Celera 500L aircraft

#70

Post by [deleted] »

m4rtink wrote: post #56
Czarcasm wrote: post #46

Earlier quoted context omitted.

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. :-)

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