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SpaceX to shrink, tweak Starship’s forward flap design, says Elon Musk

Elon Musk says that SpaceX is redesigning Starship's forward flaps. (NASASpaceflight - bocachicagal)

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SpaceX CEO Elon Musk says that there is a “slight error” with the current design of Starship’s forward flaps, necessitating a few small but visible changes on future prototypes of the spacecraft.

Measuring 9m (30 ft) wide and approximately 50m (~165 ft) from tip to tail, Starship is the combined upper stage, spacecraft, tanker, and lander of a two-stage, fully-reusable rocket with the same name. While SpaceX has a long ways to go to achieve it, the company’s ambition is for Starship and its Super Heavy booster to be the most easily and quickly reusable spacecraft and rocket booster ever built, nominally enabling the same-day reuse of both.

Beyond a Space Shuttle-style heat shield of blankets and ceramic tiles, the Starship upper stage is meant to achieve that reusability by descending through the atmosphere and landing unlike any other spacecraft, plane, or rocket ever flown. Instead of flying, gliding, or knifing through the atmosphere nose or tail-first, Starship freefalls perpendicular to the ground for the last few dozen kilometers (~10-20 mi) before aggressively flipping into a vertical orientation at the last second and landing propulsively on its tail. Now, according to Elon Musk, two of the four ‘flaps’ that largely make that exotic maneuver possible are set for a small but significant redesign.

Over the course of five suborbital test flights of full-scale Starship prototypes completed between December 2020 and May 2021, SpaceX took that exotic landing concept from the drawing board and subscale wind tunnel testing to reality. Though four of those five tests ended in destruction, their respective Starship prototypes really only failed in the last 15-30 seconds of test flights that were more than six minutes long.

After reaching an apogee of 10-12.5 km (~6.2-7.8 mi) over the course of some four and a half minutes, all five Starship prototypes successfully shut down their Raptor engines, tipped over onto their bellies, and then used a combination of small pressurized gas thrusters and four large flaps to stably fall back to Earth. Much like a skydiver can tweak their body, arms, and legs to control their orientation and attitude, Starship uses two pairs of forward and aft flaps to achieve a very similar level of control.

Thanks to Starship’s significant surface area and relatively low mass shortly before landing, that unprecedented freefall-style descent naturally slows the rocket to just 100-200 mph (~50-100 m/s) while simultaneously allowing SpaceX to avoid the massive complexity and added mass of structural wings or fins like those on the Space Shuttle. Further, whereas the Shuttle used its wings to glide (albeit like a brick) and land on very long runways, Starship is designed to use three of its six Raptor engines to flip into a vertical orientation and land much like SpaceX’s own spectacularly successful Falcon boosters.

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During the actual process of reentry, in which Starship uses a heat shield made up of ~15,000 ceramic tiles to slow from orbital (Mach 25 or ~7.5 km/s) to subsonic speeds, those same flaps also come in useful to control the vehicle’s angle of attack and thus the degree of extreme heating experienced. According to Musk, to improve the moment arm (i.e. leverage or, all else equal, torque) of Starship’s forward flaps and reduce or remove undesirable aerodynamic characteristics, SpaceX is going to shrink those forward flaps further, move them closer together and more towards the tip of Starship’s nose, and angle them toward the ship’s leeward side (back).

Apparently, those relatively minor changes mean that a portion of Starship’s forward flaps will no longer be directly subjected to reentry heating, potentially allowing SpaceX to entirely remove static “aerocovers” that wrap around the ship’s flaps to prevent superheated plasma and gas from reaching sensitive components. Ironically, SpaceX’s thermal protection team completed the installation of heat shield tiles on one of those forward flap aerocovers for the first time ever just a few days ago – a structure and portion of heat shield that will apparently no longer be needed on future Starships.

For now, though, it looks like Ship 20 will attempt Starship’s first orbital launch with its now-outdated forward flaps. Depending on how far along Ship 21 production is, the next prototype could feasibly sport that new flap design.

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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Verizon, AT&T and T-Mobile are trying to shut Starlink out before FCC vote

AT&T, Verizon and T-Mobile want 290 MHz cut from an FCC satellite plan before Thursday.

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Starlink D2D direct to device vs Verizon, AT&T (Concept render by Grok)

AT&T, Verizon and T-Mobile are asking the Federal Communications Commission to pull nearly 300 MHz of spectrum out of a proposal that would let satellite companies like SpaceX offer cell service directly to ordinary phones. The request lands one day before the agency votes on it.

The FCC will vote Thursday, October 29, on a notice of proposed rulemaking that would make an additional 482 MHz available for direct to device service, expanding the number of eligible bands from five to 13, according to the FCC fact sheet. It would also scrap the rule requiring a satellite operator to lease spectrum from carriers, replacing it with a certification that the operator has coexistence agreements in place or holds the terrestrial license itself.

That second path matters for SpaceX. As Teslarati reported earlier this month, SpaceX agreed to buy Grain Management’s nationwide 800 MHz portfolio to turn Starlink Mobile into a full US carrier, adding to the spectrum it already bought from EchoStar.

The carriers want two bands removed, 2.5 GHz and 3.45 GHz, which make up 290 MHz of the 482 MHz on the table. Through industry group CTIA, they argued that about 300 million users depend on those bands and that satellite operations in them are not technically feasible. T-Mobile, which calls 2.5 GHz the foundation of its Ultra Capacity 5G network, said in its own filing that satellite interference could wipe out up to 96% of a cell site’s uplink coverage area and cut uplink speeds by 88% to 99%.

Executives from all three carriers met with FCC staff on October 20, and T-Mobile CEO Srini Gopalan met separately with FCC Chairman Brendan Carr. T-Mobile’s role stands out because it is still SpaceX’s US launch partner for Starlink Mobile. The three carriers have also teamed up on their own satellite joint venture to pool spectrum, a move widely seen as a response to Starlink.

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SpaceX is asking for the opposite. In an October 23 filing after meetings with FCC staff and commissioners’ offices, the company asked regulators to add the 902 to 928 MHz band to the proposal. “Doing so now saves time later,” SpaceX wrote. The company also asked the FCC to modernize interference rules and align satellite deployment requirements with those for terrestrial cell networks, saying the goal is to let satellite and ground networks work together so Americans stay connected wherever they are.

The carriers have not been shy about how they view SpaceX as a competitor. On Verizon’s third quarter earnings call Monday, its chief executive said Starlink Mobile “just can’t compete with a terrestrial network” and estimated SpaceX would need four to six years and $300 billion to $500 billion to build a full US carrier network.

Thursday’s vote will not settle which bands survive. Adopting the notice opens a public comment period, with final rules to come later in the proceeding. The FCC already considered and rejected 2.5 GHz for satellite coverage once, in 2024. SpaceX also is not the only satellite player watching: the FCC approved Amazon’s $11.6 billion acquisition of Globalstar on October 27, giving its planned direct to device fleet its own mobile satellite spectrum.

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Tesla Semi catches fire in California: what we know

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Credit: KTVU

A Tesla Semi caught fire in Hayward, California, which caused both directions of traffic to shut down for hours before being completely reopened early on Wednesday, the California Highway Patrol said.

The fire occurred just after 5:30 local time in Hayward on Tuesday, as the Semi caught fire in the southbound lanes of I-880 before CHP officials made the decision to shut down both lanes of traffic due to potential risks from hazardous chemical smoke.

There were no injuries reported.

The cause of the fire is currently unknown, as neither Tesla nor the CHP have not determined a cause.

However, some images taken before the Semi was completely destroyed by the fire seem to indicate this might have been an older unit, as it appears to be one of the designs that Tesla shipped as part of its pilot program, before revising it and starting mass production just a month ago.

At the time of publication, CHP had not returned our request for a comment for additional details, including the Semi involved and any potential collaboration on an investigation between the CHP and Tesla. We will update this story when we hear back from them.

The southbound lanes were reopened at 3:30 a.m. on Wednesday, with the northbound lanes opening last night a few hours after the fire began. The CHP did state that the lithium batteries were “incredibly difficult to extinguish,” according to NBC Bay Area.

The truck’s driver said that the Semi caught fire, but he did not have an explanation.

An estimated 5,000 to 7,000 semi-truck and large commercial vehicle fires occur on U.S. roadways every year.

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Tesla’s ‘Emergency Drive Away’ function gets its first use in the real world

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Credit: Tesla

Tesla’s launch of the “Emergency Drive Away” function a few months back offered owners a safe option to evacuate an area if they were in reasonable danger. The function finally got its first use in the real world, but it appears it was by mistake.

A video shared by u/Joshalander in the r/TeslaLounge subreddit recorded the instance from his vehicle and said the incident took place in Austin this past weekend during the city’s F1 Race.

“Was charging around 6 AM this past Sunday in Austin before heading to the F1 race and heard a pop. Looked over and saw the new emergency drive-away feature in action. Genuinely felt bad for the dude when he got out and realized what happened, since he looked exhausted and only seemed to half-read the prompts.”

Emergency Drive Away unlatches the Supercharger connector from the vehicle, but still causes damage to both the car and the Supercharger. Tesla has said that it will cost up to $25,000 in repairs to have everything fixed back to normal.

Additionally, the company said that if it were not used in an emergency situation, the driver of the vehicle who activated the Emergency Drive Away feature would be responsible for all repair costs.

Tesla constitutes the following situations as reasonable justifications for activating the feature:

  • You face an immediate threat to your life or personal safety.
  • You must leave the area immediately.
  • Exiting the vehicle is unsafe.
  • Unplugging the charge connector would unreasonably delay your departure or expose you to a risk to your personal safety.

After using the feature, Tesla requires the driver to schedule Service so the car can be inspected.

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