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The potentially revolutionary Celera 500L aircraft

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Re: The potentially revolutionary Celera 500L aircraft

#171

Post by Gravityloss »

refurb wrote: post #130
Gravityloss wrote: post #74

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…

You don't have to cancel flights because of weather. I don't think many flights today are cancelled because of weather on the route there, it's the weather over each airport, which would still impact this aircraft.

Small unpressurized planes do cancel a lot of flights since they fly lower and are affected by weather.

Many other six seat planes are like that.

Re: The potentially revolutionary Celera 500L aircraft

#173

Post by VBprogrammer »

qzw wrote: post #58
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.…

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 t…

I'm calling bullshit. Compare it to the TBM900 which has a 900hp turbine engine and vastly similar layout. There is no way they can go 60 knots faster on 300 less horse power.

And even if they somehow pull off that trick, that short skinny wing will make the MU-2 feel like a safe family minivan.

Re: The potentially revolutionary Celera 500L aircraft

#174

Post by TulliusCicero »

> This and aircraft's other notable performance characteristics are made possible in large part due to its highly aerodynamic overall laminar flow shape, which produces approximately 59 percent less drag than existing similar-sized, more conventionally-shaped aircraft.

Wait, if the shape is that much more efficient, why don't we already see this sort of shape for commercial jets? Are there other compromises involved?

Re: The potentially revolutionary Celera 500L aircraft

#175

Post by Shivetya »

karlkatzke wrote: post #81
baybal2 wrote: post #49

Earlier quoted context omitted.

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.

One engine, a turbocharged V-12.

which pretty much keeps it restricted to overland only. it took a long time for the FAA to permit twins to fly across the ocean? ETOPS (Extended-Range Twin Engine Operational Performance Standards) is just what it says, twin engine but is there any possible means a passenger carrying single engine could get certification? Now as an unmanned cargo drone it might get this permission.

Re: The potentially revolutionary Celera 500L aircraft

#176

Post by VBprogrammer »

sunstone wrote: post #148
brunooo wrote: post #101

Earlier quoted context omitted.

I’m not sure those mpg numbers are correct: the more fuel efficient Piaggio EVO update, with winglets etc, in the extended range version can hold about 450 gallons of Jet A and has a 1770nm range, so even with plenty of reserves that doesn’t get it anywhere above half of 15mpg (from what I can find IFR reserve comes out to 75 gallons, thus 4.72mpg nautical or 5.4 statute). Which is why the jump in efficiency would be…

I recall from the last time this plane hit the news cycle that it is designed to cruise at 60,000 feet where air density is lower and better fuel efficiency can be had.

To put that claim into context the manned single engine piston height record is held by a specially modified Rutan Long Ez and was around 35,000ft.

Re: The potentially revolutionary Celera 500L aircraft

#178

Post by Stevvo »

nikitaga wrote: post #142
Stevvo wrote: post #88

Earlier quoted context omitted.

As awesome as the new Flight Simulator is, as an avgeek the Flight model is very disappointing. X-Plane can, and has, been used to design real world aircraft because you input the aircraft geometry and it simulates how it should fly based on that. MSFS extrapolates a lookup table over the input geometry, making it useless for real-world aerodynamic predictions. From the consumer perspective, both models are capable o…

Which aircraft were actually designed with X-plane, and why? I've heard this several times but that never made sense to me. I wouldn't be surprised if their blade element theory approach is superior to whatever Microsoft is doing (not familiar), but still both of those are optimized for realtime simulation, not for correctness. When I wanted to analyze performance of a hypothetical rigid wing hang glider I went with…

Beta eVTOL.

https://www.beta.team/

Re: The potentially revolutionary Celera 500L aircraft

#179

Post by sgt101 »

qzw wrote: post #58
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.…

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 t…

I think that the evidence can be really simple (not extraordinary) - just gas it up, fly it for 4500miles in about 11hrs.

Re: The potentially revolutionary Celera 500L aircraft

#180

Post by TLightful »

justinclift wrote: post #152
qzw wrote: 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…

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

Only if it has cryosleep chambers on-board.
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