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SpaceX CEO Elon Musk explains how Starships will return from orbit

SpaceX's Starship spacecraft will eventually have to survive orbital-velocity reentries, a spectacularly difficult feat for large spacecraft. (NASASpaceflight - bocachicagal)

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In the near future, SpaceX wants to begin putting its first two full-scale Starship prototypes through a series of increasingly challenging test flights, eventually culminating in their first Super Heavy-supported orbital launch attempts.

SpaceX CEO Elon Musk took to Twitter over the last 48 or so hours to answer a number of questions about how exactly Starship is meant to make it through orbital reentries – by far the most strenuous period for the ship and without a doubt the single most challenging engineering problem SpaceX must tackle.

Starship glows from heating as it reenters Earth’s atmosphere in this official render. (SpaceX)

Discussed yesterday on Teslarati, SpaceX technicians began the process of attaching numerous Tesla Model S/X battery packs to a subcomponent that will eventually be installed inside Starship Mk1’s nose, offering a storage capacity of up to 400 kWh. The need for all that power (Crew Dragon relies on a few-kWh battery) is directly related to Starship Mk1’s methods of reentry and recovery, recently described in detail by Elon Musk.

As noted above, ~400 kWh of batteries are needed to power the electric motors that will actuate Starship’s massive control surfaces – two large aft wings and two forward canards/fins. According to Musk, Starship’s “stability is controlled by (very) rapid movement of rear & fwd fins during entry & landing”, meaning that the spacecraft will need to constantly tweak its control surfaces to remain in stable flight.

This official graphic covers Starship’s exotic method of flight and landing. (SpaceX)

By far the biggest challenge SpaceX faces is ensuring that Starship can survive numerous orbital-velocity reentries with little to no wear and tear, a necessity for Starship to be cost-effective. In Low Earth Orbit (LEO), Starship will be traveling no less than 7.8 km/s (Mach 23, 17,500 mph) at the start of atmospheric reentry. In simple terms, the process of slowing from orbital velocity to landing on Earth involves turning the vast majority of that kinetic energy into heat. As Musk noted yesterday, this reality is just shy of unavoidable but there is some flexibility in terms of how quickly one wants to convert that energy into heat.

The fastest route to Earth would involve diving straight into the atmosphere, dramatically increasing peak heating on a spacecraft’s surface to the point that extremely exotic heat shields and thermal protections systems become an absolute necessity. SpaceX wants to find a middle ground with Starship in which the spacecraft uses its aerodynamic control surfaces and body to generate lift, slowly and carefully lowering itself into Earth’s atmosphere over a period of 15+ minutes. Musk notes that this dramatically lessens peak heating at the cost of increasing the overall amount of energy Starship has to dissipate, a bit like cooking something in the oven at 300 degrees for 30 minutes instead of 600 degrees for 10 minutes.

To an extent, Starship’s reentry profile is actually quite similar to NASA’s now-retired Space Shuttle, which took approximately 30 minutes to go from its reentry burn to touchdown. Per the above infographic, it looks like Starship will take approximately 20 minutes from orbit to touchdown, owing to a dramatically different approach once it reaches slower speeds. Originally described by Musk in September 2018 and again in recent weeks, Starship will essentially stall itself until its forward velocity is nearly zero, after which the giant spacecraft will fall belly-down towards the Earth, using its wings and fins to maneuver like a skydiver. The Space Shuttle landed on a runway like a (cement-encased) glider.

This unusual approach allows SpaceX to sidestep the need for huge wings, preventing Starship from wasting far more mass on aerodynamic surfaces it will rarely need. The Space Shuttle is famous for its massive, tile-covered delta wing and the leading-edge shielding that partially contributed to the Columbia disaster. However, it’s a little-known fact that the wing’s size and shape were almost entirely attributable to US Air Force demands for cross-range performance, meaning that the military wanted Shuttles to be able to travel 1000+ miles during reentry and flight. This dramatically constrained the Shuttle’s design and was never once used for its intended purpose.

Space Shuttle Endeavor shows off its main heat shield during an on-orbit inspection in August 2007. (NASA)

SpaceX thankfully doesn’t have its own “US Air Force” stand-in making highly consequential demands (aside from Elon Musk ?). Instead, Starship will continue the SpaceX tradition of vertical landing, falling straight down – a bit like a skydiver (or a brick) – on its belly and flipping itself over with fins and thrusters for a propulsive vertical landing. In this way, Starship doesn’t have to be a brick forced to fly, like the Shuttle was – it just needs to be able to stably fall and quickly flip itself from a horizontal to vertical orientation.

Additionally, Starship is built almost entirely out of steel, whereas the Shuttle relied on an aluminum alloy and needed thermal protection over every square inch of its hull. Steel melts at nearly twice the temperature of the Shuttle’s alloy, meaning that Starship will (hopefully) be able to get away with nothing more than ceramic tiles on its windward half, saving mass, money, and time. Once Starship completes its first 20 km (12.5 mi) flight test(s), currently scheduled no earlier than mid-October, SpaceX will likely turn its focus on verifying Starship’s performance at hypersonic speeds, ultimately culminating in its first orbital-velocity reentries.

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Eric Ralph is Teslarati's senior spaceflight reporter and has been covering the industry in some capacity for almost half a decade, largely spurred in 2016 by a trip to Mexico to watch Elon Musk reveal SpaceX's plans for Mars in person. Aside from spreading interest and excitement about spaceflight far and wide, his primary goal is to cover humanity's ongoing efforts to expand beyond Earth to the Moon, Mars, and elsewhere.

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Tesla Model Y gets fresh configuration with three highly requested features

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Credit: Tesla

Tesla has launched a new Model Y configuration in the “Premium” trim, and it comes with three highly requested features that have launched in markets outside of the U.S. and in other trims.

Tesla announced on Monday night that it has officially launched the Model Y Premium in a seven-seat configuration, which also comes standard with a 16″ touchscreen and black headliner, both of which are featured in the Model Y Performance trim.

The seven-seat configuration is highly requested by consumers and helps fill out the more spacious SUV offering that the lineup has missed outside of the Model X, which prices out many consumers. This new upgrade only costs $2,500 extra for all three features, bringing the cash price to $48,990.

The move to add the seven-seat configuration with the black headliner and additional screen size is a welcome addition, as many Tesla fans have asked the company to come out with an SUV with more seating capacity. Although it is not a full-size SUV, the additional seating will certainly attract some buyers with bigger families.

It appears the third row is slightly more spacious than the past iteration of the seven-seat Model Y, which was available in the previous design pre-Juniper:

 

Credit: Tesla

However, it definitely still appears to be pretty cramped in terms of legroom. It will definitely be a seating arrangement for smaller passengers, mostly reserved for children.

The other two upgrades are the black headliner, which was launched in other markets and in the Model Y Performance. Many owners have wanted this change, and Tesla listened, but is only offering it with the seven-seat configuration. It also has a larger 16″ touchscreen, also present in the Model Y Performance exclusively:

Credit: Tesla

It is a nice touch to add these highly requested features to the all-electric crossover, which was the best-selling vehicle in the world for the third consecutive year.

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Tesla expands its branded ‘For Business’ Superchargers

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Credit: Francis Energy

Tesla has expanded its branded ‘For Business’ Supercharger program that it launched last year, as yet another company is using the platform to attract EV owners to its business and utilize a unique advertising opportunity.

Francis Energy of Oklahoma is launching four Superchargers in Norman, where the University of Oklahoma is located. The Superchargers, which are fitted with branding for Francis Energy, will officially open tomorrow.

It will not be the final Supercharger location that Francis Energy plans to open, the company confirmed to EVWire.

Back in early September, Tesla launched the new “Supercharger for Business” program in an effort to give businesses the ability to offer EV charging at custom rates. It would give their businesses visibility and would also cater to employees or customers.

“Purchase and install Superchargers at your business,” Tesla wrote on a page on its website for the new program. “Superchargers are compatible with all electric vehicles, bringing EV drivers to your business by offering convenient, reliable charging.”

The first site opened in Land O’ Lakes, Florida, which is Northeast of Tampa, as a company called Suncoast launched the Superchargers for local EV owners.

Tesla launches its new branded Supercharger for Business with first active station

The program also does a great job at expanding infrastructure for EV owners, which is something that needs to be done to encourage more people to purchase Teslas and other electric cars.

Francis Energy operates at least 14 EV charging locations in Oklahoma, spanning from Durant to Oklahoma City and nearly everywhere in between. Filings from the company, listed by Supercharge.info, show the company’s plans to convert some of them to Tesla Superchargers, potentially utilizing the new Supercharger for Business program to advertise.

Moving forward, more companies will likely utilize Tesla’s Supercharger for Business program as it presents major advantages in a variety of ways, especially with advertising and creating a place for EV drivers to gain range in their cars.

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Tesla Cybercab ‘breakdown’ image likely is not what it seems

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Credit: TslaChan | X

Tesla Cybercab is perhaps the most highly-anticipated project that the company plans to roll out this year, and as it is undergoing its testing phase in pre-production currently, there are some things to work through with it.

Over the weekend, an image of the Cybercab being loaded onto a tow truck started circulating on the internet, and people began to speculate as to what the issue could be.

The Cybercab can clearly be seen with a Police Officer and perhaps the tow truck driver by its side, being loaded onto, or even potentially unloaded from, the truck.

However, it seems unlikely it was being offloaded, as its operation would get it to this point for testing to begin with.

It appears, at first glance, that it needs assistance getting back to wherever it came from; likely Gigafactory Texas or potentially a Bay Area facility.

The Cybercab was also spotted in Buffalo, New York, last week, potentially undergoing cold-weather testing, but it doesn’t appear that’s where this incident took place.

It is important to remember that the Cybercab is currently undergoing some rigorous testing scenarios, which include range tests and routine public road operation. These things help Tesla assess any potential issue the vehicle could run into after it starts routine production and heads to customers, or for the Robotaxi platform operation.

This is not a one-off issue, either. Tesla had some instances with the Semi where it was seen broken down on the side of a highway three years ago. The all-electric Semi has gone on to be successful in its early pilot program, as companies like Frito-Lay and PepsiCo. have had very positive remarks.

Tesla reveals its first Semi customer after launch

The Cybercab’s future is bright, and it is important to note that no vehicle model has ever gone its full life without a breakdown. It happens, it’s a car.

Nevertheless, it is important to note that there has been no official word on what happened with this particular Cybercab unit, but it is crucial to remember that this is the pre-production testing phase, and these things are more constructive than anything.

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