TSLA Market Action: 2018 Investor Roundtable

[Artful Dodger]

I'd also expect the first iteration of the Tesla Pickup Truck to have a higher price - north of $100K I'd guess.

First establish pickup truck street creds with a <100k/year production rate, then extend into mass production. The specs of the Rivian pickup truck looked good enough to me, but I guess Elon will want to beat a few of those specs.

Yes, definately better specs than Rivian. For instance, with COPV and SpaceX cold gas thrusters, it should be able to leap over obstacles instead of just jump them.

P.S. Hope they include a BRS parachute as standard equipment. Or maybe by the time the SpaceX ed. Pickup is ready, the SpaceX fairing recovery system will be working.

Cheers!

 

[winfield100]

Yes, and my (speculative) guess is that the new SpaceX Starship heat shield is basically working on the conceptual basis of a "steam iron":

• The titanium+steam heat shield is infinitely reusable. PICA-X SpaceX's ablative heat shield material at the moment which is used on the Dragon spacecraft, ablates several millimeters per landing, and is also very brittle.
• If the "ablative material" is water instead it can be refilled on Mars with low tech ISRU, while PICA-X needs a complex industrial base making carbon fiber and impregnates. PICA-X is also a classified technology.
• If the load bearing structure is pure metal then it also has very good heat conduction properties and it is also a good heat sink. While re-entry heat load is in the megawatts of heat per square meter, much of that is ablated - residual heat flux reaching the metal surface is in the kilowatts per square meter range. Still very hot but manageable.
• This new Titanium allow has similar strength per weight to carbon fiber, allowing SpaceX to standardize on metal structures alone, which is their main specialty with the Falcon 9 already.
• Metal can be 3D printed much more easily than carbon fiber.

The "ironing surface" (heat shield) would be made of O₂ doped Titanium alloy - which might also be used to make the lightweight, high-strength frame of the Tesla Pickup Truck with a body-on-frame skateboard design.

The superior strength/weight ratio of Ti-O2 is what makes it a superior material choice for a 200kWh class EV pickup truck that must carry ~2 tons of batteries in its frame. It would be a lighter yet stronger frame than steel or aluminum based frames.

To address @KarenRei's reply: obviouslyTesla would use a less expensive titanium alloy as SpaceX, but both would still use the O₂ doping process which works on a wide range of alloys. (Note: SpaceX might have already known this technique already but it could be classified like most metallurgical technologies of aerospace - now that it has been independently discovered by Chinese scientists it's out in the open for Tesla to use?)

I'd not be surprised to see shared R&D between Tesla and SpaceX, and maybe shared branding as well - like Elon already alluded to with the "SpaceX Options Pack" with the Roadster 2.

could the ablative shield be some variant on a Menger sponge? Menger sponge - Wikipedia

 

[capster]

Elon is tweeting right now, at a pretty quick pace. He seems really hyped about FSD/Nav on AP

Well now, I am glad I got FSD!

 

[Artful Dodger]

I'd also expect the first iteration of the Tesla Pickup Truck to have a higher price - north of $100K I'd guess.

Yes, the obvious target competitor, the 2018 Ford Shelby Raptor, sells for $117,460 USD.

Tesla can build a phenomenal EV truck at that price point. How about three Model 3 motors AWD and a 500 KWhr bty pack? oOF!

Cheers!

 

[Fact Checking]

OT

could the ablative shield be some variant on a Menger sponge?

So my guess is that they'd want the SpaceX Starship "steam shield" to be as robust and simple as possible, because current heat-shield designs are passive which is a big plus (you really don't want your heat shield to fail):

• a dense network of holes drilled into the rocket skin
• a really simple pressurized reservoir of at least two (but possibly three) redundant water tanks. Pressurization:
  • could in principle be completely passive, using the very significant (~5g) deceleration force during re-entry,
  • or it could be some really robust high pressure gas based pressurization system.
• before Earth launch the holes would be sealed via wax or any other material that is guaranteed to be ejected by pressure, but which keeps dust and insects out.
• in principle the water supply system could also act as coolant, with channels in the skin doubling as cooling channels - but it's probably better to have that system be a separate cooling system that transports away the excess heat.
• excess heat could also be used to autogenously pressurize the propellant tanks, which is normally performed either through the engines or through separate heaters. I.e. the cryogenic coolant would help cool down the rocket skin. But I think that would be too fragile, and there's certainly re-entry profiles that require very little engine thrust.
• I think it would also be smart to design the 'steam shield' to be self-sufficient and failure proof: i.e. if active cooling fails then that could be counteracted by rotating the ship around slowly during re-entry, and the side facing away from the plasma would be radiating away heat. This combined with higher use of water and the heat sink property of 50+ tons of metal would be calculated to be a guaranteed re-entry method even if all cooling fails.

 

[ggr]

Wait you are hiar? Let's go grab a drink.

Back to work in US tomorrow but downtown this arvo (PM me if serious).

 

[Fact Checking]

How about three Model 3 motors AWD and a 500 KWhr bty pack? oOF!

I'd say 4 motors and 'true' all-wheel-drive would be a nice feature, extreme off-road performance is so much better with what amounts to a fully flexible differential. It would also offer superior traction control on normal highways or in slippery conditions, obviously, not to mention a superior way to do a 180 degrees bootleg turn at full speed, in 'Stunt Mode'.

500 kWh is excessive I think - 4+ tons for the battery alone? 200 kWh sounds high enough to me.

 

[Fact Checking]

True historic image of Tesla accountants facing a new financial complication: "Cash Storage Hell".

 

[Artful Dodger]

could the ablative shield be some variant on a Menger sponge? Menger sponge - Wikipedia

WEEKEND OFF-TOPIC:

Yes, good idea. Indeed, silica aerogels are menger sponges already used in aerospace enginneering for composite structures:

A multi-level fractal model for the effective thermal conductivity of silica aerogel - ScienceDirect​

I think the reason for specifying a water film => steam cooling system is to allow variable active cooling via phase change + conduction by simply varying the coolant flow.

Aerogels work passively via radiated heat, with a fixed rate depending on surface temperature. So good for general structures, but not ideal for leading edge (hi-temp) components. These areas require active or ablative cooling.



^^ New materials designed to deal with hypersonic and supersonic hot stuff ^^

Cheers!

 

[replicant]

The political unrest in France is one of the many reasons why Tesla should not invest in a factory in France. And almost certainly will not.

I guess you don't know what you're talking about. I'm Parisian. Since 2012, I've been long tesla, cofounded a company that employs 5 persons and bought an appartment in Paris XVII (I hear grenades explode on the Champs Elysee from my bedroom). I was protesting along with yellow vests on Saturday. The unrest you've watched or heard about is the tip of the iceberg. What's going on on here are two ends of the political spectrum joining forces to compell politicians to commit to an ecological transition that poor people can afford. Without the latter (transition supported by all), we will end up with the far right. It is critical and urgent to get the governement to care about the way les petites gens are living. So far, they haven't care but they start to listen, now. People are finally trying to get something going (liberté, égalité, fraternité, all that) and will not accept the status quo. I recommend to listen to Nicolas Hulot when he explained why he had to resign.

 

[nwdiver]

I guess you don't know what you're talking about. I'm Parisian. Since 2012, I've been long tesla, cofounded a company that employs 5 persons and bought an appartment in Paris XVII (I hear grenades explode on the Champs Elysee from my bedroom). I was protesting along with yellow vests on Saturday. The unrest you've watched or heard about is the tip of the iceberg. What's going on on here are two ends of the political spectrum joining forces to compell politicians to commit to an ecological transition that poor people can afford. Without the latter (transition supported by all), we will end up with the far right. It is critical and urgent to get the governement to care about the way les petites gens are living. So far, they haven't care but they start to listen, now. People are finally trying to get something going (liberté, égalité, fraternité, all that) and will not accept the status quo. I recommend to listen to Nicolas Hulot when he explained why he had to resign.

Well... hopefully they find some leadership, a better narrative and clear goals or it's just going to end up like the occupy wall street protests in the US. A big waste of time that just gives a big leg up to a populist right wing moron. Right now the only clear message that's getting out is that they're angry about rich people and expensive fuel.

 

[mongo]

OT

possibly three) redundant water tanks. Pressurization:

• could in principle be completely passive, using the very significant (~5g) deceleration force during re-entry,
• or it could be some really robust high pressure gas based pressurization system.

Deceleration based pressurization can't push water uphill/ against deceleration (unless you have a piston denser than water). Having the water tank in the nose could cause self pressurization due to reentry heat.

Shuttle deceleration was under 2 G due to long time spent in thinner upper atmosphere (benefit of lifting body.

before Earth launch the holes would be sealed via wax or any other material that is guaranteed to be ejected by pressure, but which keeps dust and insects out.

Could also have smaller than insect size holes or keep air flowing out of them when outside. Need to deal with being on Mars (dust wise).

I think it would also be smart to design the 'steam shield' to be self-sufficient and failure proof: i.e. if active cooling fails then that could be counteracted by rotating the ship around slowly during re-entry, and the side facing away from the plasma would be radiating away heat. This combined with higher use of water and the heat sink property of 50+ tons of metal would be calculated to be a guaranteed re-entry method even if all cooling fails

Agree on failsafe.
If that backup works, what is the advantage of the primary steam system?

I wonder if it would be similar to the Saturn V engines which used the turbo pump exhaust as a thermal barrier in the nozzle. Feeding water at the leading edge would cause a steam barrier of rapidly expanding volume that keeps the reentry plasma away from the skin. Wouldn't need holes along the entire surface. Sort of like the water drop on a hot skillet trick, water skates around on a steam barrier instead of just boiling off.

 

[replicant]

Capital gains tax in France is 36.2%.
Income taxes are:
Below €9,700 0%
From €9,711 to €26,818 14%
From €26,818 to €71,898 30%
From €71,898 to €152,260 41%

Excluding PEA and abattement sur durée de detention and all the other niches. I never paid these 36+% on capital tax gains (and don't expect to, thanks Macron!) but I do pay more than 41% on each extra € I earn from work. No wonder why people are angry...

 

[Fact Checking]

The difference between market expectations and reality is much smaller for Q4 than it was for Q3. Q3 GAAP EPS was $1.75 and current market consensus for Q4 is ~$1.14. I would be very surprised if we do much better than $1.75 in Q4, and am currently expecting slightly less.

I expect $2+, there's a number of upsides in Q4 and very few downsides. Cash flow could be a positive surprise as well.

I.e. not as dramatic quarter-to-quarter as Q3, but better than Q3 in every metric, powerfully falsifying the residuals of the short/bear thesis, setting the stage for March 1 convertibles payback with ease, and making both the Moody's upgrade and the S&P 500 inclusion inevitable.

 

[replicant]

Well... hopefully they find some leadership, a better narrative and clear goals or it's just going to end up like the occupy wall street protests in the US. A big waste of time that just gives a big leg up to a populist right wing moron. Right now the only clear message that's getting out is that they're angry about rich people and expensive fuel.

You may question how the media is presenting this.

 

[Fact Checking]

OT,

Deceleration based pressurization can't push water uphill/ against deceleration (unless you have a piston denser than water).

If the reservoir is on the far end of the rocket it might work - but self-pressurization would probably be better.

Having the water tank in the nose could cause self pressurization due to reentry heat.

Yes - but also a separate pre-pressurized system.

Shuttle deceleration was under 2 G due to long time spent in thinner upper atmosphere (benefit of lifting body.

Starship has a much higher ballistic coefficient though, so I think peak 5 G is probably closer.

Could also have smaller than insect size holes or keep air flowing out of them when outside. Need to deal with being on Mars (dust wise).

Yeah, but smaller holes are harder to maintain. On Mars water could be allowed to freeze to seal it (titanium should be strong enough)?

If that backup works, what is the advantage of the primary steam system?

Fixed attitude of the ship, less nausea for crew and passengers.

I wonder if it would be similar to the Saturn V engines which used the turbo pump exhaust as a thermal barrier in the nozzle. Feeding water at the leading edge would cause a steam barrier of rapidly expanding volume that keeps the reentry plasma away from the skin. Wouldn't need holes along the entire surface. Sort of like the water drop on a hot skillet trick, water skates around on a steam barrier instead of just boiling off.

Maybe, but note that cooling via turbopump exhaust possibly is also an afterburner: the turbopump is fuel-rich to keep it cool, and the exhaust might be combusting near the neck where it's led into the main chamber exhaust? Might not have enough oxygen though. Also, film cooling is a secondary mechanism that helps nozzle cooling. It also solves the problem of the off axis parasitic thrust a turbopump creates.

Also, the primary role of the steam layer wouldn't be just thermal/physical insulation, but optical insulation: steam filters out the very significant radiation of 10K+ interplanetary entry plasma. At those temperatures radiative heating is 80%+ of the heat load IIRC.

This means the steam layer must be thick and uniform: 1+ cm thickness perhaps? For that the pressure and flow has to be kept high, and I'm not sure whether that's possible with a nose feed only.

Ablative heat shields evaporate along the whole surface as well. By having holes and valves they could precisely shape the steam layer during every phase of re-entry. With nose only water feed it's the weakest link with the highest heating that defines the required flow of steam. Also, the constant "outgassing" on the whole surface ensures that the hottest steam never recirculates back to the skin.

 

[anthonyj]

 

[mutle]

CBS released a new clip with at least some new parts. Elon says he doesn’t respect the SEC, which we all knew already:

Elon Musk: "I have no respect for the SEC" - CBS News

 

[Carl Raymond]

You may question how the media is presenting this.

Placards would be a good way to ensure the story cannot be spun. In all those photos I cannot see a single placard.

 

[PaulRocket]

Any way to watch the 60 minutes Elon Musk bit in Europe?