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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 adjusts one key detail of Robotaxi operations in Austin

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Tesla is adjusting one key detail of Robotaxi operations in Austin: service hours.

Tesla’s Robotaxi platform in Austin has been active since late June and has been running smoothly since then. It has its limits, as Tesla has set hours that Robotaxis can operate, as well as a distinct Service Area, also known as a geofence, which has expanded three times already.

While the geofence is currently approximately 170 square miles in size, Tesla has recently enabled freeway drives, which also necessitated an adjustment to the company’s strategy with its “Safety Monitors.”

Tesla explains why Robotaxis now have safety monitors in the driver’s seat

Traditionally, they sit in the passenger’s seat. During highway driving, they move to the driver’s seat.

These are just a few adjustments that have been made over the past two and a half months. Now, Tesla is adjusting the service hours of Robotaxi operation in Austin, but only slightly.

Tesla will now operate its Robotaxi ride-hailing service from 6 a.m. to 2 a.m., extending the hours by two hours. It previously shut down at midnight.

Tesla has implemented a variety of safeguards to ensure riders and drivers are safe during Robotaxi rides, and they have made it a point to adjust things when they feel confident that it will not cause any issues.

Many people have been critical of Robotaxi, especially because a person sits in the front of the car.

However, an accident or some type of mistake could do more damage to the autonomous travel sector than anything else. This would not just impact Tesla, but any company operating an autonomous ride-hailing service in the country.

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Tesla Model Y ownership two weeks in: what I love and what I don’t

With any new car, I don’t really find things I dislike within the first few months; the novelty of a shiny new vehicle usually wears off eventually.

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Credit: Tesla

I am officially two weeks into Tesla ownership, having picked up my Model Y Long Range All-Wheel-Drive on Saturday, August 30. I have many things I really love, and I’ll do my best to come up with a few things I don’t, although I find that to be very difficult currently.

With any new car, I don’t really find things I dislike within the first few months; the novelty of a shiny new vehicle usually wears off eventually. In the past, I’ve had a car I only kept for nine months, but I loved it for the first two months. I am sure down the road, some things about the Tesla will bother me, but right now, I don’t have too much to complain about.

As for the things I love, I’ll try to keep it to just five, and as I continue to write about my ownership experience in the coming months, I’ll see if these things change.

A Quick Rundown

In the two weeks I have had my new Model Y, I have driven 783 miles. I have driven it manually, used Full Self-Driving, navigated tight city streets in Baltimore, and driven spiritedly on the winding back roads of Pennsylvania.

I traded my ICE vehicle for a Tesla Model Y: here’s how it went

I have had the opportunity to put it to the test in a variety of ways, and I feel like I have a great idea of this car and how it handles and drives just two weeks in.

What I Love About My Tesla Model Y

I am only going to pick a handful of things, but do not take this list as a complete one. I truly have so many things I love about this car, but I want to mention the ones that are not necessarily “novelties.” I love the A/C seats, but it’s not something I feel deserves a mention here, because it would not likely sway someone to consider the car.

Instead, I want to highlight what I feel are things that truly set the Model Y apart from cars I’ve had in the past.

Tesla Full Self-Driving

Available on all Teslas, Full Self-Driving is something I use every day. It is not only a convenience thing, but it is also truly a fun feature to track improvements, and it’s been fun to show a lot of my friends who are not familiar with its capabilities just how safe and impressive it is.

My Fiancè and I have watched Full Self-Driving make slight changes in performance in the two weeks we’ve been using it. I tracked one instance on a Pennsylvania back road when the car stopped at an “Except Right Turn” Stop Sign. Initially, the car stopped, holding up traffic behind it. Just days later, FSD proceeded through that same Stop Sign cautiously, but without coming to a complete stop, which is the proper way to navigate through it.

This quick adjustment was very impressive, and it even caught the attention of my better half. I will say it has been very fun to watch her fall in love with this car after being very reluctant to watch me get rid of our Bronco Sport.

The Handling

Tesla refined the suspension with the new Model Y, and you can surely feel it. Coming from a larger SUV, I did miss being able to really push the limits of my car on a beautiful, sunny, and warm day, and the winding roads of Pennsylvania are calling me for a drive.

The way this car hugs turns and genuinely puts a smile on my face when I’m pushing it. Dare I say I like driving it more than I like it driving me?

Interior Storage

One of my biggest complaints about my Bronco Sport was that, despite being an SUV, it felt smaller than it was supposed to be. I had trouble fitting golf bags and luggage in the back without having other storage options. It led me to install a roof rack and get a cargo container. I would have to put longer clubs in the back seat so the bags could lie without clubs getting bent.

I don’t seem to have a significant problem with this in the Model Y. Plus, the frunk and the additional cargo under the floor of the trunk are great for bags and other things. It offers 10 cubic feet more of space with the seats down than the Bronco Sport does.

The Entertainment

Not only is the sound system in this car absolutely unbelievable, but I also really enjoy the Tesla Theater, which is really something that has revolutionized how we spend our time in the car.

Charging at the Superchargers has become a new way for us to spend time together. Even if it’s just 30 minutes, my Fiancé’s busy work schedule at the hospital means we don’t get to spend as much time together as we would like. The charging lets us go grab a snack, watch a movie or show in the car, and just be with each other.

It’s honestly my favorite thing about the car so far, that we’ve both truly enjoyed what it has done for us. It put a smile on my face to hear her say, “It’s just so much fun to be in this car” last night when we met friends for dinner.

What I Don’t Love

I’m just going to get nitpicky here, because I don’t have much to complain about.

The Paint

I love the Diamond Black, and it gets so many compliments. However, it sure does get dirty fast. I feel like I’m going to have to invest in a car wash membership or set aside time each week to clean it. This is not a Tesla-specific problem, of course.

Climate Control

Another “first-world problem,” but sometimes I do have trouble getting the A/C to go right where I need it. I feel like, to feel the air, I have to put the fan speed to 7 or higher.

Swing Mode has been a real savior in this sense, but my Fiancè sometimes complains that my cold air will hit her when she’s already freezing. I think this is just something I need to get used to, as the vents are significantly different than any other car. It’s really not that bad, but it is worth mentioning that we’ve both said we are still adjusting to it early on.

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Tesla brings closure to head-scratching Cybertruck trim

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(Credit: Tesla)

Tesla has ended the production and sale of a Cybertruck trim level that had many people scratching their heads. The move comes after slow sales on the trim, as many Cybertruck buyers opted for other configurations that seemed to be a better value for the money.

On Friday, Tesla officially brought closure to the Long Range Rear-Wheel-Drive configuration of the Cybertruck, a build that was introduced earlier this year at a lower price point than its All-Wheel-Drive counterparts, but missed many of the key features that made the Cybertruck, the Cybertruck.

Tesla Cybertruck RWD production in full swing at Giga Texas

Rolling the variant out at a price of $69,990, only $10,000 less than that of the All-Wheel-Drive configuration. However, it was also void of many other things:

  • Single Motor
  • Textile Seats instead of Leather
  • 7-Speaker Audio System instead of 15-Speakers
  • No Rear Touchscreen
  • No Powered Tonneau Cover for Truck Bed
  • No 120v/240v outlets

For $79,990, just $10,000 more, owners could receive all of these premium features, plus a more capable All-Wheel-Drive powertrain, which truly made this Rear-Wheel-Drive build of the Cybertruck a sitting duck for criticism.

It was simply not enough meat for the price, and demand was evidently low. From those I spoke to, orders were few and far between; people simply found more value in the All-Wheel-Drive configuration based solely on the additional motor. Adding all the premium interior and functionality features made it a no-brainer.

In a way, it seems Tesla was overly optimistic about the Rear-Wheel-Drive configuration of the Cybertruck, but even after it was launched, plenty of loyal fans were confused by it:

The Cybertruck is a great vehicle, and it is among the best vehicles in the company’s lineup. However, it really missed a price point for the Rear-Wheel-Drive configuration that was effective enough to drive people toward it. Many said they would have considered it if Tesla could have brought the price down into the high $40,000 or low $50,000 range.

I took a Tesla Cybertruck weekend Demo Drive – Here’s what I learned

It seems it just did not have the appeal to keep up. Now, Tesla has the All-Wheel-Drive and Cyberbeast for $72,490 and $114,990, respectively.

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