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Heart aerospace completes first flight of largest electric aircraft

heartaerospace.com

141–150 of 170 posts

Re: Heart aerospace completes first flight of largest electric aircraft

#141

Earlier quoted context omitted.

What happens when a large amount of these batteries get submerged in fresh or salt water?

They burn. But generally speaking, if the plane's structural integrity is degraded enough that the water gets into the battery casings, everyone onboard is probably already dead.

Depends. Everyone survived the famous ditch in the Hudson.

Re: Heart aerospace completes first flight of largest electric aircraft

#142

Earlier quoted context omitted.

Where does 12kw/kg come from? A specific type of battery? That sounds like the energy density for lithium alone. There may be architectures like flow batteries which could get close for some chemistries, but a standard battery (intercalation of ions) cannot get remotely close, even in theory.

This was claimed by CATL chief battery scientist recently or at least that's what the press claimed could be mistranslation from Chinese to English.

As far as I could glean from the internet, it's a theoretical limit for lithium, rather than for a lithium-air battery. Any future device that gets close to that limit won't be a battery as we know it.

Re: Heart aerospace completes first flight of largest electric aircraft

#143
post #101

Earlier quoted context omitted.

Specific to the electric plane, you remove some of the battery weight, as that energy would then come from the catapult. But, as a general thing? I don't see it happening. There's a TON of complexity in a catapult system. Plus, the amount of spilled champagne in first class is going to ruin a lot of suits and blouses. Can't have that. ;)

> There's a TON of complexity in a catapult system. But it's all on the ground.

True, but you'd need, at minimum, a well-trained crew to operate. The catapult settings vary by take-off weight. Who manages that? Does each airline run their own crew (contract) as they do other ground services? Or does the airport run it?

The airframes would have be heavier, beefed up to take that load. FWIW, the Navy version of the F-35 weighs ~5000lbs more than the AF version's 29000 dry weight (granted, that's also additional folding wing changes). It also costs about 20% more per unit.

Anyways, it's all certainly possible. Just impractical without a real need.

But catapult launch ballistic passenger gliders would be pretty cool.

Re: Heart aerospace completes first flight of largest electric aircraft

#144

Earlier quoted context omitted.

They burn. But generally speaking, if the plane's structural integrity is degraded enough that the water gets into the battery casings, everyone onboard is probably already dead.

Depends. Everyone survived the famous ditch in the Hudson.

Would the famous ditch in the Hudson have broken the casings of the batteries?

Re: Heart aerospace completes first flight of largest electric aircraft

#145

Earlier quoted context omitted.

This was claimed by CATL chief battery scientist recently or at least that's what the press claimed could be mistranslation from Chinese to English.

As far as I could glean from the internet, it's a theoretical limit for lithium, rather than for a lithium-air battery. Any future device that gets close to that limit won't be a battery as we know it.

okay but anyway for electric commercial aviation 1000-1200w/kg would be enough to replace 70-80% of all flights.

Re: Heart aerospace completes first flight of largest electric aircraft

#146

VTOL aircraft have the same distance capabilities and make more sense in a lot more scenarios than this, with way more flexibility. It’s obviously larger but I’m just not sure of potential advantages over other modes of transport currently available and in the near future

I really like the STOL "blown lift" Electra design. It never has to do the dangerous transition to an inefficient VTOL mode, and can still land in very small places. Although, this is a much small aircraft, and it's a hybrid.

https://electra.aero/

https://www.youtube.com/watch?v=4INw9bclxeI

Re: Heart aerospace completes first flight of largest electric aircraft

#147
post #75

27 mins endurance (?) for $5 of power. Not bad. I rent a 172 and have been paying a $5/h fuel surcharge for the past few months due war in Iran - but at UK avgas prices 27 mins in my plane would be $55ish. Haven’t looked into the details but kind of crazy impact on economics of aviation if this size plane (10x 172 MTOW) can actually do useful short haul

I’m thinking they got this wrong by an order of magnitude.

The region they did this flight in charges ~$.25/kw. So they would have had to do the entire flight with 20kw/h or an average of 40kw of output. That’s 60hp, or about a third what your Cesnna uses on climbout. Even if you give them a very low price of $.10/kw then they are flying with less than the Cessna on climbout. Hell, a Cessna in level flight uses ~80 kw.

In other words, they are claiming that they can fly this thing on a VW beetle engine, or the PR guy got the number wrong.

Re: Heart aerospace completes first flight of largest electric aircraft

#148
post #125

Earlier quoted context omitted.

[flagged]

>Chat told me this type might be an option: but why do you think this was a meaningful contribution to the discussion?

Because their profile says they are “always happy to chat”. ;-)

Re: Heart aerospace completes first flight of largest electric aircraft

#149
$5 of energy at even $0.10/kWh is 50 kWh. One horsepower is roughly ~754 watts. 50 kWh for 27 min at 100% efficiency means 111 kW sustained output which is 147 HP. The math is wrong, there’s no way this plane flies with only 147 HP. That’s roughly what a Cessna 172 has for engine power.

Conclusion: AI wrote this article and it has at least one and probably several more errors.

Re: Heart aerospace completes first flight of largest electric aircraft

#150
post #80

> Powered entirely by batteries, X1 used approximately $5 worth of electricity during its first flight It's fun to look at the arithmetic behind this to pull out the assumptions. To lift a 25000 lb mass 1100 ft in the air requires just over 10kWh, but that's assuming no air resistance or friction, so let's triple the energy needed to 30 KWh. Let's add another 10 kWh for forward distance covered (assuming it was mostl…

> I'd guess the actual flight time was only 10 of the 27 minutes, 30 kWh used over 10 minutes is 300kW of peak power I would note this line from the press release: > its all-electric propulsion system delivered more than one megawatt of power. I assume this was peak during takeoff.

Planes still need like half throttle to maintain altitude, that’s why airplane engines are rebuilt every few thousand hours vs lasting hundreds of thousands of miles (tens of thousands of hours) for a car engine that only uses a small fraction of its power to keep a car moving.
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