Live coverage of the countdown and the launch of the SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida. The Starlink 4-20 mission will launch SpaceX’s next batch of 51 Starlink broadband satellites and Boeing’s passenger payload to demonstrate broadband communications technology. Follow us Twitter.
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SpaceX launched a Falcon 9 rocket Sunday night with 51 Starlink internet satellites and a payload that would use a spaceflight-built orbital transport vehicle to ascend into a higher orbit to test Boeing’s broadband communications technology.
Liftoff from Space Launch Complex 40 at Cape Canaveral Space Force Station aboard a Falcon 9 rocket occurred at 10:09:40 p.m. EDT (0209:40 GMT Monday), marking the 40th launch of SpaceX of the year.
There was an 80% chance of weather suitable for a launch chance Sunday night, according to the US Space Force’s 45th Weather Squadron.
The main payload for Sunday night’s mission, designated Starlink 4-20, was the next batch of SpaceX’s Starlink Internet satellites. The rocket carried 51 flat-packed Starlink spacecraft, fewer than the number carried in a typical Starlink launch from Florida, to accommodate the passenger payload.
The secondary passenger was the chemical-propulsion Sherpa-LTC orbital transport vehicle that rides on the Starlink payload stack inside the Falcon 9 payload cruiser. The Sherpa-LTC orbital transport vehicle was designed by Spaceflight, a Seattle-based spacecraft developer and rideshare launch broker, to transport Small satellites are hosting experiments to different altitudes and inclinations after an initial flight into orbit from a large rocket.
The Sherpa-LTC orbital transport vehicle on the Starlink 4-20 mission carries Boeing’s Varuna Technology Demonstration, or Varuna-TDM. The mission is designed to demonstrate technologies and perform in-orbit performance testing of the V-band communications system, a lunar constellation of 147 satellites to provide broadband connectivity to commercial users and the United States government.
Boeing said the Varuna-TDM mission will provide potential users of the broadband satellite constellation “an opportunity to assess the performance of fifth-band communications links and ascertain their attributes and acceptability for specific applications.”
The Falcon 9 rocket deployed the Sherpa-LTC Transfer Vehicle with the Varuna tech experimental mission into a semi-circular orbit at an average altitude of approximately 192 miles (310 kilometers) above Earth, and an inclination of 53.2 degrees to the equator.
Sherpa-LTC deployed first about 49 minutes into the flight, followed by the separation of 51 Starlink satellites at T+ plus 72 minutes.
The spaceflight solar-powered orbital transport vehicle will perform a series of burns to reach a circular orbit 620 miles (1,000 kilometers) above Earth, where it will begin the experimental Varuna tech mission. The experimental payload Varuna tech was designed and built by Astro Digital, which also provided the command and control system for the Sherpa-LTC orbital transport vehicle.
The Sherpa-LTC uses a two-way, “green” or non-toxic propulsion system developed by Benchmark Space Systems.
“Sherpa-LTC’s transportation capabilities combined with the reliability and consistency of Starlink missions create an ideal solution to a customer’s unique mission needs,” said Kurt Blake, CEO and President of Spaceflight. “Our OTV removes the barriers that make it difficult for spacecraft to reach unfamiliar orbits in LEO and beyond. We are keen to continue to provide innovative, cost-effective, and reliable space transportation services to our customers and partners such as Astro Digital.”
With Sunday’s Starlink 4-20 mission, SpaceX launched 3,259 Starlink Internet satellites, including prototypes and test units that are no longer in service. Sunday night’s launch was SpaceX’s 59th mission primarily dedicated to moving Starlink’s internet satellites into orbit.
The SpaceX launch team, stationed inside the Launch Control Center south of Cape Canaveral Space Force Station, began loading ultra-cold, condensed kerosene and liquid oxygen thrusters into the 229-foot (70-meter) Falcon 9 at T-minus 35 minutes.
Compressor helium also poured into the rocket in the last half hour of the countdown. In the last seven minutes before takeoff, the Falcon 9 Merlin’s main engines were thermally adapted to fly by a procedure known as “chilldown”. The Falcon 9’s guidance system and range safety are also configured for launch.
After liftoff, the Falcon 9 missile directed 1.7 million pounds of thrust — produced by nine Merlin engines — to point northeast over the Atlantic Ocean.
The missile exceeded the speed of sound in about one minute, and then shut down its nine main engines two and a half minutes after takeoff. The boost stage was fired from the Falcon 9’s upper stage, then fired pulses from cold gas control thrusters and extended titanium grille fins to help steer the vehicle back into the atmosphere.
Brake burns slowed the missile as it lands on the “read instructions only” drone ship about 400 miles (650 kilometers) after about eight and a half minutes of take-off.
The first stage for Sunday’s launch is scheduled for B1052 in SpaceX’s inventory. The booster craft made its seventh flight into space. This vehicle flew as a side booster on two Falcon Heavy missions in 2019, then was converted to fly as a first stage on a Falcon 9 rocket, starting earlier this year.
The Falcon 9’s reusable payload fairing was discarded resulting in a second stage burn. The rescue ship was also at a station in the Atlantic to retrieve the halves of the nose cone after they had been sprayed under parachutes.
The first-stage landing on Sunday’s mission occurred moments after the Falcon 9’s second-stage engine failed to deliver the Starlink satellites into a primary transition orbit. A second upper stage burn about 45 minutes after launch put the payloads into orbit appropriate for the separation.
After the Sherpa-LTC payloads were launched, the upper stage retaining rails were removed from the Starlink payload stack, allowing the flat-packed satellites to fly free of the Falcon 9’s upper stage into orbit. The 51 spacecraft will launch and power the solar arrays through automated activation steps, then use krypton-fueled ion engines to maneuver into their operational orbit.
The satellites will use onboard thrust to do the rest of the work to reach a circular orbit 335 miles (540 kilometers) above Earth.
Starlink satellites will fly in one of five orbital “shells” in different directions to SpaceX’s global Internet. After reaching their operational orbit, the satellites will enter commercial service and begin transmitting broadband signals to consumers, who can purchase Starlink service and connect to the network through a ground station provided by SpaceX.
Rocket: Falcon 9 (B1052.7)
Payload: 51 Starlink and Sherpa-LTC satellites (Starlink 4-20)
launch site: SLC-40, Cape Canaveral Space Station, Florida
Lunch date: 4 September 2022
launch time: 10:09:40 PM EST (0209:40 GMT)
weather forecast: 80% chance of acceptable weather; low risk of upper level winds; Reduced risk of conditions unfavorable to enhanced recovery
Recovery from reinforcement: Drone “Just Read Instructions” Drone East of Charleston, South Carolina
AZIMUTH LAUNCH: the Northeast
target orbit: 188 miles by 196 miles (304 kilometers by 316 kilometers), 53.2 degrees miles
Launch timeline:
- T+00:00: take off
- T+01: 12: maximum air pressure (Max-Q)
- T+02:29: First stage main engine cut-off (MECO)
- T+02:33: Phase separation
- T+02:39: Second stage engine ignition (SES 2)
- T+03:13: Get rid of the calm
- T+06:05: Ignition of burning entering the first stage (three engines)
- T+06:36: First stage entry combustion cut off
- T+08:05: 1st stage burner ignition (single engine)
- T+08:27: First stage landing
- T+08:45: Engine cut-off in second stage (SECO 1)
- T + 45: 25: ignition of the engine in the second stage (SES 2)
- T+45: 27: second stage engine cut-off (SECO 2)
- T+49: 28: Sherpa-LTC chapter
- T + 1: 12: 23: Starlink satellite separation
Job stats:
- The 174th launch of the Falcon 9 since 2010
- The 182nd launch of the Falcon family since 2006
- Seventh launch of Falcon 9 Booster B1052
- Falcon 9 #149 launched from Florida’s space coast
- Launch of Falcon 9 No. 96 from the 40 . platform
- The 151st release overall from the 40 board
- Flight 116 of the reused Falcon 9 booster
- The launch of the 59th dedicated Falcon 9 with Starlink satellites
- The 40th session of Falcon 9 will start in 2022
- SpaceX40 launching in 2022
- The 38th orbital launch attempt from Cape Canaveral in 2022
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