Connect with us

News

SpaceX Starship pop test opens the door for 60,000 foot hop [update]

SpaceX has successfully destroyed a Starship 'test tank' for the fourth time. (NASASpaceflight - bocachicagal)

Published

on

SpaceX has successfully destroyed a Starship ‘test tank’ for the fourth time, opening the door for the first high-altitude prototype to roll to the launch pad as soon as tomorrow.

The culmination of three nights and more than 20 hours of concerted effort, SpaceX was finally able to fill Starship test tank SN7.1 with several hundred tons of liquid nitrogen before dawn on September 23rd. With just an hour left in the day’s test window, SpaceX closed the tank’s vents, allowing its cryogenic contents to boil into gas and expand with no outlet. At 4:57 am CDT, SN7.1 burst, bringing its lengthy test campaign to a decisive end.

A handful of hours later, new road closure notices revealed SpaceX’s plan to roll Starship SN8 – the first full-size prototype and first ship meant for high-altitude testing – from its Boca Chica factory to the launch site.

Update: All road closures planned for Starship SN8’s roll to the launch pad (Sept 24) and first test campaign (Sept 27-29) have been canceled. Stay tuned for updates on the high-altitude prototype’s test schedule.

Short of new information from SpaceX or CEO Elon Musk, little is known about the results of SN7.1’s lengthy test campaign, but the fact that it survived two nights of nondestructive testing – including the use of hydraulic rams to simulate Raptor thrust – effectively clears Starship SN8 for suborbital testing. Based on a speculative, amateur analysis of the aftermath of SN7.1’s burst test, it can also be tentatively concluded that the tank failed almost exactly where one would expect it to: the in-situ weld attaching the upper tank dome to SN7.1’s steel ring hull.

SN7.1’s forward dome appears to have cleanly sheared off around much of its circumferential weld joint – exactly what one would theoretically expect from a good, uniform weld. Assuming that SN7.1 reached pressures well above 8.5 bar (~125 psi) before it burst, the tank’s final test can likely be deemed a success.

Advertisement
-

The very same day SpaceX kicked off what would become Starship SN7.1’s last burst test attempt, teams worked to install functional flaps on a full-scale Starship prototype (SN8) for the first time ever. Effectively answering the question of whether SpaceX would fully outfit the ship with a nosecone and flaps before its first acceptance tests, SN7.1’s successful pop was followed by road closure notices for SN8’s transport to the launch pad around dawn on September 24th and cryptic “SN8 Testing” as early as September 27th.

As of September 23rd, SN8’s twin aft flaps – large aerodynamic control surfaces meant to stabilize free-falling Starships – have been fully installed alongside ‘aerocovers’ that will protect each flap’s control mechanisms. The only hardware Starship SN8 is missing is a ~20m (~60 ft) tall nosecone, two smaller forward flaps, and the plumbing needed to access a smaller liquid oxygen “header” tank located in the tip of said nose.

At the moment, SpaceX has installed one Starship nosecone prototype atop five unpressurized rings – creating a full nosecone stack. That particular prototype has no liquid oxygen header tank, however, meaning that SpaceX would likely need at least a day or two to weld one of the noses with a header tank atop one of several finished five-ring sections. In other words, to transport SN8 to the pad tomorrow, there’s almost no chance that SpaceX will have time to finish and install a proper nosecone on the prototype, meaning that the company has chosen to test the Starship before that milestone.

Starship SN8’s tank section is effectively complete as of September 23rd. (NASASpaceflight – bocachicagal)

Doing so should reduce any inconvenience caused by vehicle failure in the event that Starship SN8’s acceptance test campaign doesn’t go as planned. In hindsight, the inclusion of Starship SN8’s aft flaps and aerocovers during the ship’s first major tests was likely a necessity, given that almost half of each flap and its support structure is installed directly to the skin of its liquid oxygen tank. Theoretically, when chilled to the temperature of liquid nitrogen or oxygen, the diameter of the stainless steel rings Starship SN8 is built out of could shrink by as much as 0.3% (~20 mm or ~0.8 in).

Only half of Starship SN8’s aft flaps will be directly subject to that tank contraction, resulting in a relatively complex environment for such a large, high-stress mechanical system. As such, testing flap actuation under cryogenic loads is likely a critical part of SN8’s cryogenic proof test, otherwise meant to demonstrate the structural integrity and functionality of Starship’s propellant tanks. If SN8 rolls to SpaceX’s launch facilities on schedule, the Starship’s first cryogenic proof test could begin as early as 9pm CDT (UTC-5) on Sunday, September 27th.

Check out Teslarati’s Marketplace! We offer Tesla accessories, including for the Tesla Cybertruck and Tesla Model 3.

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.

Advertisement
Comments

News

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.

Published

on

By

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.

Advertisement
-

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.

Continue Reading

News

Tesla Semi catches fire in California: what we know

Published

on

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.

Continue Reading

News

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

Published

on

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.

Continue Reading