Live coverage of the countdown and launch of a SpaceX Falcon 9 rocket from Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The Falcon 9 rocket will launch 40 broadband satellites for OneWeb. Follow us on Twitter.
SFN Live
Teams at Kennedy Space Center in Florida are counting down to launch of a Falcon 9 rocket at 5:27 p.m. EST (2227 GMT) Thursday with 40 satellites for OneWeb’s broadband constellation, the first of three dedicated Falcon 9 flights OneWeb booked with SpaceX after Russia’s government refused to continue launching spacecraft for the commercial internet network.
The Falcon 9’s upper stage will head into a 373-mile-high (600-kilometer) polar orbit to deploy the 40 satellites, while the first stage booster will return to Cape Canaveral for landing.
There is a 90% chance of favorable weather for launch Thursday, according to the U.S. Space Force’s 45th Weather Squadron. Forecasters predict mostly clear skies for the sunset launch attempt, with mild temperatures and north winds.
The launch was delayed from earlier in the week as SpaceX prepared the Falcon 9 launcher inside a hangar a quarter-mile south of pad 39A.
The 40 satellites on-board the Falcon 9 rocket will bring the total number of OneWeb spacecraft launched to 504. OneWeb needs nearly 650 satellites to complete its first-generation broadband network.
“This launch is very, very important for us because it’s going to allow us to increase significantly the coverage of our service,” said Massimiliano Ladovaz, OneWeb’s chief technology officer. “With this launch, we’ll be able to cover up to 25 degrees north and south (latitude). This means the entire United States, and half of Australia down, and (much of) South America.”
In a pre-launch interview with Spaceflight Now, Ladovaz said the OneWeb satellites already in orbit are performing well. OneWeb’s satellites are built in a factory just outside the gates of Kennedy Space Center by a joint venture between OneWeb and Airbus Defense and Space. The satellites are are designed to beam low-latency broadband internet signals to customers around the world.
“Our failure rate is very, very, very low,” Ladovaz said. “I think it’s probably less than 1%, and we want to keep it that way, even lower than that. The satellites have had very few issues.”
Based in London, OneWeb is one of several operators either already launching large fleets of internet satellites, or planning to begin launches soon.
SpaceX has launched more than 3,500 Starlink internet satellites using the company’s own Falcon 9 rockets. The 464 OneWeb satellites that were previously launched flew into orbit on 13 Russian Soyuz rockets purchased through Arianespace, the French launch services provider, and one flight on an Indian GLSV Mk.3 rocket.
Amazon plans to launch its first two prototype internet satellites of a planned constellation of 3,236 spacecraft next year on the first flight of United Launch Alliance’s new Vulcan rocket.
But OneWeb’s satellite deployment schedule hit a roadblock earlier this year after Russia’s invasion of Ukraine.
Arianespace was on the hook with OneWeb for six more Soyuz launches from the Baikonur Cosmodrome in Kazakhstan, including a 14th launch that was set to take off in March. But Russia’s space agency set conditions on the mission after rolling the rocket and the OneWeb satellites to a launch pad at Baikonur, including a demand that the UK government give up its stake in OneWeb.
The UK government declined, and OneWeb announced March 3 it was suspending launches from Baikonur. OneWeb reported a loss of $229.2 million on its financial statements as a result of the termination of the planned Soyuz launch in March. The financial charge also covers losses associated with the postponement of subsequent Soyuz missions, and the loss of 36 satellites stranded in Kazakhstan and not returned to OneWeb by Russia, which runs the Baikonur Cosmodrome.
Less than a month after Soyuz launches were suspended, OneWeb announced an agreement with SpaceX to launch some of its remaining satellites. OneWeb finalized a similar agreement with New Space India Limited, or NSIL, the commercial arm of India’s space agency, for launches on Indian rockets.
“Unfortunately, all those delays we had with the Ukraine crisis slowed us down,” Ladovaz said. “That’s why I’m so excited about this launch today.”
The contract with SpaceX was surprising to many satellite industry watchers because OneWeb is an indirect competitor in broadband market. SpaceX sells Starlink service directly to consumers, while OneWeb sells to enterprises and internet service providers to provide connectivity for entire businesses or communities.
Ladovaz lauded SpaceX for their responsiveness to OneWeb’s needs, saying there has been “absolutely no friction” between the companies. “We are not competing in the same markets. This is about, really, cooperation.”
“Honestly, it’s incredible what SpaceX can achieve in such a short amount of time,” he said. “It’s in another dimension compared to other launch vehicle providers.”
In one example of SpaceX’s rapid pace of development, the launch provider designed and built a new dispenser to accommodate OneWeb’s satellites inside the Falcon 9’s payload fairing. For its past missions, OneWeb used a carbon composite mounting tower built in Sweden by Beyond Gravity, formerly known as RUAG Space, with a capacity to hold up to 36 satellites.
SpaceX developed a multi-tiered metallic dispenser capable of accommodating up to 40 satellites. OneWeb’s satellites separated from their rocket in groups of four on the previous launches, while SpaceX will release OneWeb’s spacecraft in three batches of 13 or 14 satellites.
“It’s actually a completely different design … It’s incredible,” Ladovaz said. “If you think about it, designing from scratch a dispenser in two months, when SpaceX came back to us and proposed that idea, to be honest with you, we were a little bit concerned. But they explained that to us, and we accepted it and moved along with the idea.
Launching with SpaceX offers an extra benefit for OneWeb, which can deliver its satellites to the rocket integration hangar just a few miles away from their factory, instead of flying satellites to far-flung launch sites in Kazakhstan, Russia, French Guiana, or India.
“It’s so much easier,” Ladovaz said. “You can start shipping one satellite at a time instead of waiting to have all the satellites ready in one shot. You can integrate day by day.”
And OneWeb’s satellite builders in Florida will finally be able to see one of their launches in person.
During Thursday’s countdown, SpaceX’s launch team will turn over control of the Falcon 9 countdown to an automated computer sequencer 35 minutes before liftoff. About a million pounds of super-chilled, densified kerosene and liquid oxygen will be pumped into the 229-foot-tall (70-meter) rocket ahead of the 5:27 p.m. launch time.
After teams verify technical and weather parameters are all “green” for launch, the nine Merlin 1D main engines on the first stage booster will flash to life with the help of an ignition fluid called triethylaluminum/triethylborane, or TEA-TEB. Once the engines ramp up to full throttle, hydraulic clamps will open to release the Falcon 9 for its climb into space.
The nine main engines will produce 1.7 million pounds of thrust for 2 minutes and 17 seconds, propelling the Falcon 9 and the OneWeb satellites into the upper atmosphere as it heads south-southeast from Kennedy Space Center. Then the booster stage will shut down and separate from the Falcon 9’s upper stage to begin maneuvers to return it to Landing Zone 1 at Cape Canaveral Space Force Station.
While the upper stage lights its single engine to accelerate to orbital velocity, the first stage will reignite three of its engines for a “boost back” burn begin thrusting it back toward Florida’s coast. The booster, designated B1069 in SpaceX’s fleet of reusable rockets, will perform two more retrorocket firings with a subset of its engines to slow for landing. Touchdown at Landing Zone 1 is expected 7 minutes and 45 seconds after launch to wrap up the booster’s fourth flight to space. The rocket landing will be accompanied by double sonic booms that could be heard across Florida’s Space Coast.
A SpaceX recovery ship is on station to recover the Falcon 9 rocket’s payload fairing after the nose cone’s two clamshell halves parachute into the sea downrange from Cape Canaveral. The payload fairing will jettison from the rocket about three-and-a-half minutes into the flight, shortly after ignition of the Falcon 9’s upper stage engine.
After turning from an initial south-southeast course to a more southerly trajectory, the upper stage will complete its first burn eight-and-a-half minutes into the flight to place the OneWeb satellites into a preliminary parking orbit. The Falcon 9 will use a southern launch corridor parallel to Florida’s East Coast to reach the north-south polar orbit required for OneWeb’s constellation.
SpaceX launched its first polar orbit mission from Cape Canaveral Space Force Station in 2020, using the southern launch corridor for the first time since 1969. The OneWeb mission Thursday will be SpaceX’s eighth polar orbit launch from Florida, and the first to take off from pad 39A, the historic seaside facility originally used for Saturn 5 rocket launches in the Apollo moon program.
The Falcon 9’s upper stage will coast over the Caribbean Sea, Central America, and the Pacific Ocean before a three-second restart of the Merlin Vacuum engine about 55 minutes after launch to circularize the orbit before deployment of the 40 OneWeb satellites.
The satellites will separate in groups over a half-hour, with the final set of spacecraft expected to separate from the rocket about 1 hour and 29 minutes into the missions.
The OneWeb satellites, each weighing about 325 pounds (147.5 kilograms at launch), will deploy solar panels and activate xenon ion thrusters to maneuver into their operational orbit at an altitude of 745 miles (1,200 kilometers).
ROCKET: Falcon 9 (B1069.4)
PAYLOAD: OneWeb 15 (40 OneWeb satellites)
LAUNCH SITE: LC-39A, Kennedy Space Center, Florida
LAUNCH DATE: Dec. 8, 2022
LAUNCH TIME: 5:27:48 p.m. EST (2227:48 GMT)
WEATHER FORECAST: 90% probability of acceptable weather
BOOSTER RECOVERY: Landing Zone 1, Cape Canaveral Space Force Station, Florida
LAUNCH AZIMUTH: South
TARGET ORBIT: 373 miles (600 kilometers) altitude; 87 degrees inclination
LAUNCH TIMELINE:
-
- T+00:00: Liftoff
- T+01:12: Maximum aerodynamic pressure (Max-Q)
- T+02:17: First stage main engine cutoff (MECO)
- T+02:20: Stage separation
- T+02:28: Second stage engine ignition
- T+02:34: First stage boost back burn ignition
- T+03:22: First stage boost back burn cutoff
- T+03:33: Fairing jettison
- T+06:04: First stage entry burn ignition
- T+06:21: First stage entry burn cutoff
- T+07:18: First stage landing burn ignition
- T+07:45: First stage landing
- T+08:31: Second stage engine cutoff (SECO 1)
- T+55:14: Second stage engine restart (SES 2)
- T+55:17: Second stage engine cutoff (SECO 2)
- T+58:28: Separation of 14 OneWeb satellites
- T+01:13:53: Separation of 13 OneWeb satellites
- T+01:29:18: Separation of 13 OneWeb satellites
MISSION STATS:
- 188th launch of a Falcon 9 rocket since 2010
- 197th launch of Falcon rocket family since 2006
- 4th launch of Falcon 9 booster B1069
- 161st Falcon 9 launch from Florida’s Space Coast
- 58th SpaceX launch from pad 39A
- 152nd launch overall from pad 39A
- 128th flight of a reused Falcon 9 booster
- 1st SpaceX launch for OneWeb
- 54th Falcon 9 launch of 2022
- 55th launch by SpaceX in 2022
- 53rd orbital launch attempt based out of Cape Canaveral in 2022
Email the author.
Follow Stephen Clark on Twitter: @StephenClark1.
from Spaceflight Now https://ift.tt/iLHY1n3
via World Space Info
0 comments:
Post a Comment