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Dan Thomas

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Any details on the battery?
BJC
All-electric Grand Caravan makes maiden flight
As configured, the Magni500-powered Grand Caravan can carry 4-5 passengers on flights up to 100 miles, taking into account the need for reserve power, says Ganzarski.

Magnix and AeroTEC are working on certificating that aircraft by the end of 2021. By then, Ganzarski predicts battery technology will have advanced to where the Grand Caravan will be able to operate 100-mile flights carrying a full load of nine passengers.
 

BBerson

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Dan Thomas

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Two ton battery. No room for a passenger.
From that article:
The flight does not herald the near-term introduction of all-electric, passenger-carrying Cessnas. The cabin of the plane was obstructed by two tons of lithium-ion batteries and cooling equipment, with little room for passengers. It certainly wasn’t a cabin setup that would make any sense commercially.

“Yeah, I couldn’t fit a person in that aircraft. There was not even an attempt to put the batteries in a more convenient place,” said MagniX CEO Roei Ganzarski. “This specific eCaravan was designed as a flying test bed.”

The flight proves a plane this size can be powered by an electric motor.


That's about what I figured. It's just a proof-of-concept thing, waiting for much better batteries that might be years away. Or decades. I'm reasonably certain that some fantastic batteries will appear someday, but they might show up just in time for some other completely different propulsion system shows up and they aren't needed. The Lycoming X-7700 radial engine comes to mind; it appeared just as jet engines were making their way into airliners.

I really wish journalists would do their research. We wouldn't be seeing breathless articles about how we'll very soon by flying in electric commuter planes.
 

BJC

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“Yeah, I couldn’t fit a person in that aircraft. There was not even an attempt to put the batteries in a more convenient place,” said MagniX CEO Roei Ganzarski. “This specific eCaravan was designed as a flying test bed.”

The flight proves a plane this size can be powered by an electric motor.
I.e., “This was all done for publicity.”


BJC
 

Riggerrob

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I suspect that STCed electric Caravans will carry batteries in quick-change belly panniers ... resembling the baggage panniers oftenretro- fitted to single-engined Cessnas.
 

stanislavz

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2000 kg per 6 persons - 333 kg per person or 13 tesla battery packs 65 kwh, or 50kw useable with reserve

+- as rotax 912 at cruise with 75% of power.

And take any eu ul class tandem aircraft with 160-200mph cruise - and you are in better position. But only single seater. And with batteries around you

Or do it in twin mustang style... Two seater and safer :)
 

12notes

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Dan Thomas said:
That's about what I figured. It's just a proof-of-concept thing, waiting for much better batteries that might be years away.
No, they stated that they have a battery weight of "about a tonne" right now in a plane whose useful load with a much, much heavier engine is 3,200 lbs. If you ignore the extra few hundred pounds switching the engine for an electric motor, and use the metric ton, that's still a plane with 1,000 lbs. useful load right now, without any advances in batteries needed, which they claim can hold 4-5 passengers on flights up to 100 miles right now. They backed this claim up with the flight. The numbers make sense, and need no advancements in technology at all to work.

I.e., “This was all done for publicity.”
Or they prioritized getting it flying over the final location of the batteries, and it was easier to get the cg perfect by strapping them in the cabin. Which is exactly the path I would've taken as well, and makes sense when developing prototypes. You make sure it works before you spend time on the details. They're not hiding it, the quote about not having room for passengers in this version isn't some insider secret, it is from the CEO of the company.

Look, I'm the first to jump on unrealistic claims of battery life and technology advancements. There are many companies that make sketchy claims and are little more than dreams and a CAD model, and I tend to hammer on every one. But this continual beating up of actual flying planes really needs to stop. Magnix has been really open about their planes, they have been really good about stating what they're doing, what stage of development they're in, what the limitations are, and what are hopeful projections. The article clearly states "Magnix and AeroTEC hope to eventually carry nine people 100 miles once the technology has advanced, but that won’t happen until after the initial aircraft’s expected certification in 2021. " Note that they don't give a date for that goal, just hope eventually after certification. There is no ridiculous claim here. There are no unrealistic numbers with their flight. They've actually done it. It's a flying electric plane that can go 100 miles and has the weight capacity to carry 4-5 passengers. It is not in it's final form, but now they know it works they can worry about locating the batteries optimally. It's a much smaller problem than getting it working in the first place.

What benefit would it be for them to keep this secret?

They're not building planes for GA or airlines, electric power isn't realistic for either right now. They're building short hop airplanes with lower cabin capacity, but also greatly reduced fuel costs and lower noise, which the current state of electric power is sufficient to accomplish. Far from perfect, but adequate enough for a few short hop airlines to be interested. I'm fairly sure they've done way more math on the financial aspect of the number of passengers than anyone here.

Save the vitriol for the charlatans. There's plenty of them, you'll have ample opportunity. Back off on the people that are actually doing the work and building for a realistic market with what is available now.
 

Dan Thomas

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No, they stated that they have a battery weight of "about a tonne" right now in a plane whose useful load with a much, much heavier engine is 3,200 lbs. If you ignore the extra few hundred pounds switching the engine for an electric motor, and use the metric ton, that's still a plane with 1,000 lbs. useful load right now, without any advances in batteries needed, which they claim can hold 4-5 passengers on flights up to 100 miles right now. They backed this claim up with the flight. The numbers make sense, and need no advancements in technology at all to work.



Or they prioritized getting it flying over the final location of the batteries, and it was easier to get the cg perfect by strapping them in the cabin. Which is exactly the path I would've taken as well, and makes sense when developing prototypes. You make sure it works before you spend time on the details. They're not hiding it, the quote about not having room for passengers in this version isn't some insider secret, it is from the CEO of the company.

Look, I'm the first to jump on unrealistic claims of battery life and technology advancements. There are many companies that make sketchy claims and are little more than dreams and a CAD model, and I tend to hammer on every one. But this continual beating up of actual flying planes really needs to stop. Magnix has been really open about their planes, they have been really good about stating what they're doing, what stage of development they're in, what the limitations are, and what are hopeful projections. The article clearly states "Magnix and AeroTEC hope to eventually carry nine people 100 miles once the technology has advanced, but that won’t happen until after the initial aircraft’s expected certification in 2021. " Note that they don't give a date for that goal, just hope eventually after certification. There is no ridiculous claim here. There are no unrealistic numbers with their flight. They've actually done it. It's a flying electric plane that can go 100 miles and has the weight capacity to carry 4-5 passengers. It is not in it's final form, but now they know it works they can worry about locating the batteries optimally. It's a much smaller problem than getting it working in the first place.

What benefit would it be for them to keep this secret?

They're not building planes for GA or airlines, electric power isn't realistic for either right now. They're building short hop airplanes with lower cabin capacity, but also greatly reduced fuel costs and lower noise, which the current state of electric power is sufficient to accomplish. Far from perfect, but adequate enough for a few short hop airlines to be interested. I'm fairly sure they've done way more math on the financial aspect of the number of passengers than anyone here.

Save the vitriol for the charlatans. There's plenty of them, you'll have ample opportunity. Back off on the people that are actually doing the work and building for a realistic market with what is available now.
That article I quoted said two tons. One metric tonne is 1000 kg, or 2204 pounds. There's a big discrepancy here somewhere.
 

12notes

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That article I quoted said two tons. One metric tonne is 1000 kg, or 2204 pounds. There's a big discrepancy here somewhere.
From the first second article:
"The Magni500 on the Grand Caravan receives power from a 750V lithium-ion battery system weighing roughly one tonne "

2 metric tonnes doesn't make sense because that would make the empty plane about 700 lbs over the maximum landing weight, and more so with the pilot.

EDIT: corrected from first article to second, this one: All-electric Grand Caravan makes maiden flight
 
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Dan Thomas

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My statement doesn’t qualify as vitriol where I come from.
BJC
We old, experienced guys are entitled to some skepticism. We've seen, many times over the years, an awful lot of "new, revolutionary" aviation stuff that never lives up to its billing. Anyone my age that had the time and motivation to read all the Popular Mechanics magazines and their numerous competitors will know what I mean. We've been in and around this flying stuff for a long time, longer than many of the members here have even been alive. Maybe longer than their parents have been alive.

1591233483089.png

Physics is always getting in the way.
 

12notes

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We old, experienced guys are entitled to some skepticism. We've seen, many times over the years, an awful lot of "new, revolutionary" aviation stuff that never lives up to its billing. Anyone my age that had the time and motivation to read all the Popular Mechanics magazines and their numerous competitors will know what I mean. We've been in and around this flying stuff for a long time, longer than many of the members here have even been alive. Maybe longer than their parents have been alive.


Physics is always getting in the way.
That doesn't excuse you when the physics and math works out, and there is an actual, physical example of it, and the company isn't making any claims of it doing anything but exactly what it does. You're entitled to nothing in this case.
 

BBerson

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From the first article:
"The Magni500 on the Grand Caravan receives power from a 750V lithium-ion battery system weighing roughly one tonne "
Unable to find this comment in first article (thread post #1) or any article in this thread.
 

12notes

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Unable to find this comment in first article (thread post #1) or any article in this thread.
Sorry, it's in the second article, not the first. I'll correct my post. This one, third paragraph from the end:


It's a bit more aviation focused than the Seattle Times or Yahoo finance, so I think it's more likely to get the details of the plane correct.
 
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BBerson

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Well, it said "roughly" one tonne. (could be 3000 pounds)
And, the other article said 2 tons (with cooling system). So details matter.
 
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