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Tesla Model S Floats Well Enough To Act As a Boat, According To Elon Musk

It appears a Tesla Model S car can float and effectively drive on water. Tesla CEO Elon Musk tweeted a video of a Model S car which was able to float well through a flooded tunnel in Kazakhstan. Musk also noted that the company "definitely" doesn't recommend trying this -- but still vouched for the availability of this feature. The Guardian reports: The car appears to power through the water using the thrust of the wheels turning in the water, as the bow wave laps over the car's bonnet. Most internal combustion engine cars are sunk in water when the exhaust becomes flooded, which is why serious off-roaders have big exhaust scoops leading to the roof. Electric cars don't suffer from that particular issue, but how the rest of the car will react is unknown.

7 of 238 comments (clear)

  1. Wow the car knowledge here is bad by Anonymous Coward · · Score: 5, Informative

    "Most internal combustion engine cars are sunk in water when the exhaust becomes flooded, which is why serious off-roaders have big exhaust scoops leading to the roof"

    No. Most internal combustion engines are destroyed via hydrolock when (significant) water enters the intake of the engine. Because it can't be compressed, the engine basically explodes internally (pistons, valves, etc, etc). If water enters the exhaust and the engine is running, this is usually not a big deal because the air pressure from the engine will push it back out. Also, the exhaust valves don't suck in air so it will take some serious water pressure to get past those.

    Typically, to combat this, the intake will have a snorkel attached to it and that will be as high as possible, thus preventing water entry into the intake. The exhaust may be raised as well (but that is not absolutely necessary) and this is a serious consideration if the engine is to be turned off while submerged (as then water will enter the combustion chamber through the exhaust valves, hydrolocking when you try to start it again).

    1. Re:Wow the car knowledge here is bad by msauve · · Score: 4, Informative

      "once a Tesla starts taking on water I'd imagine it'd sink like a lithum rock."

      Which is to say, it would still float? Lithium has a density similar to wood (pine).

      --
      "National Security is the chief cause of national insecurity." - Celine's First Law
  2. Synopsis wrong by MouseR · · Score: 3, Informative

    Musk didn't say (less even vouch) for the availability of this "feature". It's not a feature. It's a capability inherent to any car with closed cabin. All cars will float for a brief period of time (which is what Musk said: it will float for a brief period of time).

    The batteries and electrical system is isolated enough to sustain sub-bar pressures and will hapilly drive along as the engine is not dependant on any air intake system not being flooded.

    Technically, all EVs should be able to do this for a period. DONT drive across the lake.

    Ranged-extended vehicles (Gen 1 & 2 Volt, BMW i3, Fisker Karma) dont have this luxury. While the electrics will continue working, any flooding of the ICE will require major repairs.

    Disclaimer: I own a Gen2 Volt.

  3. Re:Batteries by necro81 · · Score: 4, Informative

    Electronics in automotive environments tend to be very well sealed, because they are exposed to all kinds of crap. Rain is the least of it: snow, salt, sand, mud, marine air, gasoline, motor oil, washer fluid - all of these would utterly destroy electronics if they were not well protected against it. The electronics enclosures, cabling, and connectors used in automobilies are typically rated to IP55 at least, and typically are IP67. Once you have sealed it well enough to keep out all the crap you'd encounter on the road, you get protection against temporary submersion more or less for free.

  4. Re:Batteries by Anonymous Coward · · Score: 2, Informative

    Yes, you can. The stuff is called "Lith-X", and we were trained in its use. Lith-X was applied by the bucket load. For very small fires, like foils, something that resembled a salt shaker was used.
    Of only minor interest here: we were working with Lithium-6...

  5. Re:Floats unlike Tesla by Anonymous Coward · · Score: 3, Informative

    WHoooooosh.

  6. Re:Float? Not quite. by kamakazi · · Score: 4, Informative

    hmm, that is a point. If the wheel stays up in the fender it may act as a very inefficient impeller, taking in water at the rear of the fender opening, the fender liner acting as the casing of a very poorly coupled pump.

    It would work better if it was a fully skirted fender, which they aren't, so most of the water being pumped is going to just blast out sideways, mostly out, because the inside of the wheel well is lower that the outside.

    Just guessing, without modeling, I think the thrust would be mostly down, with some backwards.

    I don't know my Tesla models that well, but if it is AWD any thruster effect from the front wheels would be less, because of the larger wheel well clearances for turning, and would disappear almost entirely when the wheels were turned left or right at all.

    Teslas probably have an advantage in this regard, because they have a pretty taught suspension, and probably won't droop as much as the cars us mere mortals drive, which at full droop can be almost entirely out of the wheel well, below the body of the car.

    You are correct, I had not considered the ducting action of the fenders. However I stand by my final judgement that the car in the video is not floating.

    --
    "Proximity to wonder has blunted our perception and appreciation of it" --Tim Hartnell in 'Exploring ARTIFICIAL INTELLI