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Comment Re:Wonder how it compares to Airlander (Score 1) 111

That accident sure was a black eye for them... but the design is now better because of it. Also, gotta love having an aircraft whose crashes are in slow motion ;) "Coming soon on World's Least Dramatic Air Crashes!"

I imagine for the pilot it was sort of like when you're driving down a slope on ice and you lose traction, and you end up skidding down the whole slope at a several kilometers per hour: First, alarm and futile attempts to regain control, followed by acceptance, then "Okay, you can stop any time now...."

Comment Re:Going Howard Hughes... (Score 3, Informative) 111

Airships are not party balloons; they don't "pop" when you make a hole in them. They have low overpressure and a huge volume to surface area, so a "bullethole" is just a slow leak; it's not even a reason to land. A helicopter is far more vulnerable to small arms fire than a helium airship.

As for what it buys over a helicopter, show me a helicopter that can move 50-500 tonnes payload at a per-kilogram rate cheaper than a freight truck while flying halfway around the world without refueling. Because that's what people are looking to build with this new generation of airships. Even Airlander 10, which is just a commercial prototype for the Airlander 50, carries more payload than the largest helicopter used by the US military, the Sikorsky CH-53E Super Stallion.

Comment Re:Going Howard Hughes... (Score 3, Interesting) 111

A common usecase for large airships is remote mining operations. They need big, heavy pieces of equipment brought into places without roads. Currently, the first step is to build a road - which is expensive and environmentally destructive. An airship needs only a clearing - and the "skycrane" variants don't even need that.

Another advantage is that it's much easier to design them to carry "bulky" cargoes than airplanes. Again, especially "skycrane" designs where the cargo hangs beneath.

Comment Re:Wonder how it compares to Airlander (Score 2) 111

Given the fact that it's rigid, and given the size of Hangar Two and the fact that the frame is said to take up much of the hangar, it's probably much larger than Airlander 10.

Probably also doesn't look like a giant rear end ;) Even if it's a lifting body, the fact that it's a rigid airship (from the description) means that they can shape it however they want. So probably something like a flattened teardrop, if they go for the hybrid (lifting body) approach. Which generally seems pretty popular these days, for good reason (lots of extra lift at little cost, higher top speeds because you don't have to have as large of a cross section for a given cargo, etc). But of course there's nothing here to suggest whether it's actually a hybrid.

Comment Re:Money to burn I guess (Score 2) 111

It's easier to hate on?

I'm wondering what the "innovation" is. Because I'm sure that he's not doing this without some angle, something unusual that he's doing with this one vs. other airships. Some sort of wow factor.

Sergei, blow me away with something totally crazy. Like make its skin transparent, fill it with heliox and have people live inside the envelope farming, like an Earth prototype of a Venus colony ;)

But honestly, my expectations are that it's a generic freight carrier, and that the twist would be that it's a rigid lifting body. Maybe if we're really lucky, solar-powered too.

Comment Re:Going Howard Hughes... (Score 4, Interesting) 111

I personally find it very exciting. I knew that Alphabet had rented the Moffett Field hangars from NASA and were rennovating them. But their official stated purpose for doing so was to store a number of company planes. This is the exciting part:

Engineers have constructed a metal skeleton of the craft, and it fills up much of the enormous hangar.

So first off:

1) It's a rigid airship. Which used to be common but is now rare. Zeppelin NT is a semirigid, with a trilobate truss inside, but there's not many other examples. Rigids are favored when you're building something very large, as they reduce the stress on the skin.

2) It's huge. Hangar 2 is 52,1 meters high, 90,5 and 327,7m long.

I hope it's a lifting body! If I'm not mistaken it'd be the world's first rigid lifting body airship (correct me if I'm wrong!). Either way it's yet another sign that we're - at least temporarily - entering a new lighter-than-air renaissance. Who knows whether it will last, but it's great to see so many companies giving it another shot, making use of modern technology and design. Because there have been some huge improvements since the old Akron / Macon days. Also wonder about the fuel. Something like Blau gas, so it's buoyancy-neutral as it burns?

Of course, not everything in the article is exciting or new...

He went on to describe a prototype he was considering of a helium-based craft that appeared to breathe. "And so the way that works is that the helium in the main envelope is taken and stored in bags inside the airship at a slightly higher pressure," he said. "As you do that, air is taken in from the outside into essentially like lungs that are attached in the side of the vehicle. So the analogy of breathing is a good one. And the overall lift of the vehicle is equal to the weight of the air that is being displaced by the helium. And as you change that, you can control the amount of buoyancy that the vehicle has."

Um... yes, that's how lift cells work.... you either use them or you use ballonets, your choice... there's a couple other possibilities, like high overpressure superpressure balloons, or compressors + gas tanks, but the former doesn't scale, and the latter generally comes with too much mass and cost penalties with too poor responsiveness.

BTW, for those not familiar with the Macon and the Akron, I definitely recommend reading about them. They were literal flying aircraft carriers. You know how a landing jet on an aircraft carrier catches a cable with a hook? They did that too, but in the other direction - they caught a "trapeze" on their topside. They were then raised into the hangar, which was designed for five airplanes.

They unfortunately weren't long in service. Both of their losses could have been prevented with any combination of better weather prediction, computer controls, and better lift control. The Macon's loss was also stupid in that they were flying with unrepaired structural damage, out doing fleet maneuvers.

Comment Re:Couldn't the battery be replaced instead? (Score 2) 177

An EV battery is not some 12V with a couple leads sticking out of it. Just like an engine, it requires rigid attachment to the frame, integration with the airflow circulation, etc. It's not just sitting in some compartment that you can open up, it generally runs the length of the entire vehicle, having a meaningful impact on structural strength. The EV pack is also significantly heavier than most car engines (~500-600kg for Teslas - you can get whole cars lighter than that). And HV connectors are a lot more sensitive than just some random wire. When it comes to engineering, designing the HV connectors to survive numerous removal / reconnection connection cycles without degradation is one of the hardest parts. It's one thing to demonstrate simply swapping it once, but ensuring reliability is a much more challenging part.

Beyond that, your comparison of a car engine not designed for swapping with an EV pack designed for swapping is facetious.

Comment Re:Okay, but... (Score 2) 177

What is that website exactly? For one, it only seems to list Europe. Secondly, when you limit it to *fast chargers* (since that's what's being discussed), Tesla comes out in the middle in Europe. Lastly, the site doesn't seem to list nearly as many Tesla superchargers as Tesla itself does.Even if you only count "locations" rather than "chargers", then Tesla has 296 in Europe, while that map lists 146.

Comment Re:Sigh (Score 5, Insightful) 177

Global network.

10,000 chargers.

That's one every 5750 (ish) square miles.

Well done.

Did you seriously just divide Earth's total land area by the number of chargers? Great to know that I can pop over to a Tesla supercharger when I'm in the middle of Antarctica, Greenland or the Sahara.

Tesla Superchargers are only found in:
  * The US (not including Alaska)
  * Southern Canada (and not all of southern Canada)
  * Europe
  * Israel
  * UAE
  * Southeast coastal Australia (plus one in the west, and a couple in NZ)
  * Japan
  * South Korea
  * East China

In the US, Superchargers are spaced 50-100 miles apart along all but a handful of interstates (the latter to be added by the expansion), as well as smaller highways in more densely populated areas (many more to be added by the coming expansion). Which is more than enough to drive cross country. Note that we're only talking about superchargers; there are also many more slower chargers in place.

Comparing it to gas stations is a stupid comparison, firstly because there are vastly more cars on the road, and thus vastly more gas stations needed. But beyond that is the more basic point: EVs don't do most of their charging at superchargers. Gas vehicles must fill up at gas stations. EVs overwhelmingly don't fill up at superchargers. Superchargers are for trips.

Comment Re:Couldn't the battery be replaced instead? (Score 2) 177

Exactly this. The concept of "battery swapping" is at least as difficult as the concept of "engine swapping" (for someone else's engine, at that). It can be done, but you're dealing with a very large, heavy component critical to vehicle structure, with sensitive connections, and very high value, which high stockpiling requirements - multiplied by the number of batteries on the market. And mandating that everyone use the same battery pack will never fly - not out of stubbornness, but because different vehicles represent entirely different capacity needs, power needs, form factors, price ranges, etc, and the technology is a constantly moving target. The sort of battery you're going to put in a 2wd luxury sedan is not the sort of battery you're going to put in an electric jeep, which is not the same sort of battery you're going to put in in a sports car, which is not the same sort of battery you're going to put in a delivery truck, which is not the same sort of battery you're going to put in a motorcycle... (continues ad nauseum).

Battery swap is fun to prototype, but it's not at all practical. Faster and faster charging is the way forward. Which BTW comes inherently with increased capacity. If you go from a 100kW pack made of cells that can charge in half an hour to a 200kW pack made of cells that can charge in half an hour**, then you're going from charging at 200kW to 400kW, and doubling the kilometers-range-per-hour-spent-charging.

** - Pretending that charging is linear, rather than fast in the beginning and slow at the end, for simplicity's sake. ;)

Comment Re:Okay, but... (Score 2) 177

Freed patents are by definition not "proprietary".

Perhaps you mean "non-standard". But again, it's hard to declare Tesla to not be standard when there's more Tesla superchargers than others. And while there's a single widely accepted standard for lower rate charging (J1772 - which Tesla supports), there's a number of competing fast-charging "standards" for fast charging, so again it's hard to declare one arbitrary other standard to be "the" standard.

I'd also argue that Tesla's standard for fast charging is the best one. High peak power, compact footprint, broadly adaptable, etc.

Comment Re:Okay, but... (Score 1) 177

A lot of it simply comes down to battery size. As cells charge in parallel, then for a given cell chemistry and format, the rate you can safely charge is proportional to the vehicle's capacity. And Teslas have huge capacities compared to most other EVs (for example, the Ioniq is only 28kWh).

Now, of course, that's conditional on vehicles using the same types of cells. For example, if one vehicle is using cobalt-based 18650s and another is using, say LiPo or high-rate spinel cells, then the latter can take a much higher power for a given amount of capacity.

Obviously the charger can limit your rate. But in general the charger will be designed to max out at the maximum capability of the pack.

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