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Comment Re: Screw it (Score 4, Informative) 160

To elaborate on the above AC's point, here's a list of SpaceX launches (starting with the first oceanic "landing" attempt) and their success/failure rate.

29-sep-2013: Ocean failure
03-dec-2013: No attempt
06-jan-2014: No attempt
18-apr-2014: Ocean success
14-jul-2014: Ocean success
05-aug-2014: No attempt
07-sep-2014: No attempt
21-sep-2014: Ocean success
10-jan-2015: Drone ship failure
11-feb-2015: Ocean success
02-mar-2015: No attempt
14-apr-2015: Drone ship failure
27-apr-2015: No attempt
**********28-jun-2015: In-flight failure
22-dec-2015: Ground pad success
17-jan-2016: Drone ship failure
04-mar-2016: Drone ship failure
08-apr-2016: Drone ship success
06-may-2016: Drone ship success
27-may-2016: Drone ship success
15-jun-2016: Drone ship failure
18-jul-2016: Ground pad success
14-aug-2016: Drone ship success
**********01-sep-2016: Pre-launch testing failure
14-jan-2017: Drone ship success
19-feb-2017: Ground pad success
16-mar-2017: No attempt
30-mar-2017: Drone ship success
01-may-2017: Ground pad success
15-may-2017: No attempt
03-jun-2017: Ground pad success
23-jun-2017: Drone ship success
25-jun-2017: Drone ship success
05-jul-2017: No attempt

These don't even tell the whole story because not only has their success rate gone way up, but they've also been attempting to land from increasingly difficult flight envelopes that previously they wouldn't have even attempted from (and simply flown legless / finless rockets)

The issue with testing rocket landing is, you can't just do it in some research lab; you can only do it by actually landing rockets, and changing whatever doesn't work. That's the only way you can learn of your failure modes. Sure, you can use scaled-down testbeds, and SpaceX did that with the Grasshopper series - but there's the difference between a testbed and something that actually goes to orbit. There's a reason that SpaceX used to call them "experimental landings". I don't think they use that term any more; nowadays a landing failure would be seen as a pretty significant setback.

Comment Re:I'm shocked! (Score 5, Insightful) 160

So.... he didn't read the requirements before he started

Right, so you apparently think there was just some printed list sitting around of what NASA will and won't accept when you want to do something that's not been done before (propulsive crew landing)? As was made abundantly clear, what NASA will and won't accept came out of discussions with NASA. It became increasingly clear over time that they weren't going to allow it, so they cut it. I'm sure that you and your army of space psychics could have handled it better.

didn't look at previous NASA designs used successfully,

Yeah, let's just go back to Redstones. Because that will surely lead us to the future that SpaceX is working to achieve! The whole point is to innovate in ways that can make access to space cheaper and more routine, not to keep repeating what we know doesn't allow for cheap, routine access to space.

Even his cars are low-sales,

I love this double talk that you get from Slashdotters. On one hand, bringing a brand new mode of transportation from almost nothing to huge demand, to the degree that each new model is produced is in volumes an order of magnitude than the previous and yet accumulates even greater waiting lists, isn't happening nearly fast enough, that Tesla is "low sales" (actually, no, they're not, not when you take into account market segment). On the other hand, we're also always flooded with posts about how Tesla isn't paying dividends and keeps having to take capital rounds. So let me get this straight, Slashdot. Tesla is supposed to have, in a decade, gone from "design concept for an electric car" to "selling more cars than the major automakers", of an entirely different type of vehicle, while paying dividends and not raising capital. Am I understanding this correctly?

Tesla's rate of growth has been phenomenal. The fact that you find an automaker going from almost nothing to opening up factory lines to produce hundreds of thousands of $35k+ vehicles per year in under a decade to be way to slow, boggles the mind.

Sure, it's nice that he's throwing his money away so others don't have to, but as yet he hasn't really achieved much that couldn't have been done better, faster and more usefully than just giving that same money to NASA

For decades, US launch costs had stagnated. In the matter of a few years, SpaceX cut them to a small fraction of their former value - and they've only barely just started reuse. Again, the fact that you find this to be "not really achieving much" and that you think NASA would have done better (despite decades of distinctly not doing better) likewise boggles the mind.

Comment Re:More difficult with people? (Score 3, Insightful) 160

beta testing his shitty half-assed autopilot junk on the buying public

Questions Answer: Yes
(1) Have you ever used Autopilot before? 99 %
(2) Are you familiar with the car warnings that Tesla provides about how Autopilot is to be properly used? 98 %
(3) Are you aware that when you first enable the Autopilot, you have to do so through the Drivers Assistance section of Settings on
the center screen? 93 %
(4) Are you aware / Do you know that after enabling Autopilot, you had to agree to an acknowledgment box which stated that
Autopilot “is an assist feature that requires you to keep your hands on the steering wheel at all times” and that “similar to the
autopilot function in airplanes, you need to maintain control and responsibility for your vehicle” while using Autopilot? 99 %
(5) Do you know that each time you activate Autopilot, a message appeares on the screen behind the steering wheel stating:
“Please Keep Your Hands On The Wheel; Be Prepared To Take Over At Any Time“? 96 %
(6) Based on these communications, have you understood that when using Autopilot, the driver is expected to maintain control of the
vehicle at all times? 98 %
(7) Has the name “Autopilot” caused you to believe that the car is fully autonomous, meaning that it does not require the driver to be
supervising the car? 7 % (No : 93 %)

There was an interesting study done (unrelated to the German owners survey above) which showed that the minor autopilot failures (occasional lane drift, unexpected speed changes) are ironically improving consumer safety. Users were well aware of its ability to make mistakes specifically because they're common enough, and this keeps the vast majority of users from treating the vehicle like a tool you don't have to pay attention to it; instead they tend to treat it more like cruise control. As automation improves, the danger may counterintuitively increase as users get used to never having to do anything when the vehicle is driving and thus stop paying attention.

At the same time, despite the frequency of errors, the overwhelming majority of users felt that its failures presented either no risk, or little risk, as they tend to be things that any reasonable driver could react to (in the same way that we don't fear cruise control because if it's looking like it's going to drive us into the rear of the car ahead of us, we slow down). E.g. autopilot never just suddenly jerks the wheel to hard right in the middle of a road or whatnot. They also get quite used to what situations you use it in and what you don't use it in (just like people do with cruise control); the fact that the system won't let you use it when it perceives its ability to follow the road to be too poor doesn't even need to factor into the equation.

Comment Re: Screw it (Score 5, Insightful) 160

That's the thing I don't get. SpaceX is saving the US government huge amounts of money. Yet so many Slashdotters have this weird conception that they're a giant leach sucking government budgets dry. Their conception is precisely the opposite of reality. ULA has been getting an unbelievable sweetheart deal for government launches, getting paid even when they don't launch anything, and charging massive fees when they do, while also getting government subsidy to develop new craft. SpaceX paid back its COTS funding in spades versus what was being doled out to ULA.

Comment Re:I'm shocked! (Score 5, Informative) 160

It's like you didn't even read the article or pay attention to what he said. So I guess someone has to repeat it for you.

NASA's regulations for propulsive landing of a Dragon 2 capsule are too difficult to reasonably meet. So they're dropping propulsive landing from Dragon 2. Meaning it can't land on Mars either. At the same time, they've decided that there's a better approach to landing on Mars than Dragon 2's approach of a bottom-mounted heat shield and side-mounted thrusters.

And for the record, that better approach is what they're looking at with ITS - a side lifting body heat shield with base thrusters for landing. The latter spreads the heat out over a much larger area (Dragon 2 had no option for that because it had no giant, partially empty propellant tanks attached) and increases the length of time over which the heating occurs, slowing the rate.

It'll be interesting to see their changes to ITS. I'm glad to see that "smaller" is among them - I like ambition, but ITS was a step too far, IMHO.

Comment Re:Dear clients: (Score 3) 243

Where I am, our code doesn't work with newer versions of a dependency library. Two developers have tried to work around the incompatibility, and failed. So until we can scrounge together enough time to redevelop the frontend from scratch, we're stuck installing old versions of the library, and just hoping that no OS changes render older versions of the library inoperable - otherwise we won't be able to upgrade OSes either.

That said, this doesn't fit the topic, because our boss knows all of this. We keep our boss well in the loop. He used to work as a programmer the software, and still does some work on it from time to time. That's IMHO how it should be.

Things work best when workers aren't afraid of their boss. I hate Machiavellian workplaces.

Comment I've said it before, and I'll say it again: (Score 2) 125

Autopilot is the best excuse for a driver getting into an accident that ever was invented. "No officer, it wasn't me! My car did it on its own!"

Thankfully, it's easy for Tesla to avoid legal liability for things like this because the car logs when autopilot is actually in use and what it's doing. Unfortunately, it doesn't help with the PR aspect, as the media just blindly reports that it was Autopilot before taking the time to find out if it actually was.

Comment Re: We'll be fine. (Score 1) 201

So the model S isn't very good around the track.

You're interpreting "not being designed for the track" as "has bad handling", as if the two are at all the same thing. The Model S has superb handing, and reviews are almost uniformly in agreement on this. It's not a track car because it's not designed to handle track cooling loads, having nothing to do with handling.

The track car market is much smaller than the luxury sedan market, so obviously it isn't their target. That said, they do plan to make an actual track car, which will be their next generation Roadster (the first generation, like Tesla's other cars, was a road car, not a track car). It's also targeting a bone-crushing sub-2-second 0-60, too - they're calling the drive mode "Ultimate Plaid" ;) And that's stock, with stock tires, etc.

Comment Re: We'll be fine. (Score 1) 201

This is about the closest you'll get

I don't know if that's the drivetrain I sampled. But from the back seat, on a short stretch of road closed off for the Tesla event, the Model 3 launched with ferocious grip and absolutely zero drama. It wasn't quite the chest-collapsing wallop of a Model S P90D in Ludicrous mode, but without a stopwatch, I'd say the Model 3 I rode in zipped from a dead stop to 75 mph a bit quicker than a Subaru WRX STI—silently.

Sadly, there was no place to get a good impression of the Model 3's steady-state handling or lateral grip, but our driver zig-zagged through a handful of quick slalom maneuvers. The Model 3 stayed nearly flat, with plenty of grip. Credit Tesla's low-slung platform, which puts the mass of the batteries (and in this case, the dual motors) as low as possible in the package.

From this, you apparently derive that it has horrible handling?

Expected to be 400-600 kilos lighter than a Cayenne in the baseline version, and similar to a Mustang. The center of mass is ridiculously low. It should stick to the roads like a dream.

If you're basing your expectations on the S, again, that's baffling, because the S has gotten superb reviews on its handling. Here's Jalopnik's, for example:

On an open, winding stretch of Skyline Road the P85D feels at home. It's a road I know, and the Tesla hunkers down and devours it. But underneath the sheer speed is that battery pack and extra motor, mounted oh-so-low in the car. Through high-speed sweepers and cambered corners is this thoroughly odd sensation of ample mass sliding underneath you, but it never feels cumbersome. There's a certain amount of security that comes with hurtling that amount of weight with such a lower center of gravity through corner after corner, and the tires and motors do their best to keep it in check. There's grip for days, more than I expected, and the only time the Tesla felt out of its element was in the tightest, single-lane switchbacks that vein out from Skyline. Good sports sedans shrink around you; the Model S doesn't, but that seems like a lowly demerit given everything else it's capable of.

S is much heavier than 3, because it's a larger vehicle and has a larger pack. The all-aluminum frame helps compensate (Model 3 is steel + aluminum), but the baseline 3 will almost certainly be sub-2 tonne, with a lot of the speculation in the 1,6 to 1,9 tonne range.

Comment Re: We'll be fine. (Score 2) 201

For some more figures....

Porsche Cayenne: Baseline (2012 and earlier) 7,3sec; Diesel V6 (2013) 6,8 sec; Diesel V8 (2013) 5,3 sec; S (2011) 5,6 sec; S (2015) 5.1 sec; S hybrid (2011) 6,2 sec; S E-hybrid (2016) 5,2 sec; Turbo (2015 and earlier) 4,2-4,3 sec; Turbo S (2016) 3,8 sec.

Ford Mustang: Ecoboost (2015, various): 5,3-6,0 sec; V6 (2016): 5,3 sec; GT (2015, various) 4,3-4,7 sec

It's funny how much we've gotten used to these sort of performance figures being affordable (mid-5 figures). 5 seconds was supercar speeds back in the 1980s (e.g. 1985 Ferrari Testarossa). Nowadays, for an econobox you get figures like 8,3 sec (2016 Civic EX sedan); 8,0 sec (2017 Camry XSE); etc. And even the econoboxes have options to improve performance - for example for $35k you can get a Camry getting closer to a baseline Model 3's performance (XSE V6, 6,1 sec), and Honda has the sporty Civic Type R beating a baseline Model 3 (4,9 sec) for around the same price (although with less impressive standard features and much higher operating costs). By comparison, the 1973 Honda Civic had a 0-60 of 19,1 sec ;)

Comment Re: We'll be fine. (Score 3, Informative) 201

I don't understand either of the above posts.

5.6 seconds is the acceleration of a low-end Mustang (which also costs about the same as a baseline Model S). A typical econobox sedan these days does it in about 8 seconds, more like 9 for a typical crossover. On the opposite side of the spectrum, the fastest Veyron is 2.4, and the fastest Model S 2.34. The performance option for the Model 3 hasn't been announced (although it's been announced that there will be one); I'd expect it to be in the 3.5-5 second range, depending on a lot of factors. It won't be able to hit the top S speeds because it can't support as big of a pack; nor would Tesla want to make it be able to, as they want to have a reason for higher-end buyers to choose the higher-end vehicle class (Model S).

As for driving range: the more powerful you make an EV, the further it's range. It's the opposite of gasoline vehicles. In addition to needing a larger pack for more power, more power also means lower resistance conductors; this means lower energy loss at cruising speeds.

Now, if the GP meant "if you're constantly pushing a vehicle to its limits, you go a shorter distance with a more powerful vehicle", that's obviously true for both EV and gasoline. But range figures (for both EV and gasoline) are not for track duty, they're for normal road duty.

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