SpaceX has a busy weekend ahead of it

Company will attempt to launch two used boosters.

SpaceX has launched five rockets so far during the first quarter of 2018, but now the company will amp up that pace by tryng to go for two launches in four days. If successful with these flights, the cadence would put the company two months ahead of 2017's record pace, when SpaceX launched a total of 18 rockets. Last year, SpaceX didn't launch its seventh rocket until June 3.

The company's first attempt comes Friday, when SpaceX is scheduled to lift a batch of satellites for the Iridium NEXT mobile communications fleet. This is the fifth set of 10 satellites in a series of 75 total satellites SpaceX will launch for Iridium. This flight will occur from the company's launch pad at Vandenberg Air Force Base in Southern California. Then, on Monday, SpaceX plans to launch its 14th cargo supply mission to the International Space Station from Cape Canaveral in Florida.

Iridium-5

After engineers with Iridium solved an issue with the payload of communications satellites, SpaceX set a launch date of March 30, with an instantaneous launch window of 10:13am ET. The 10 communications satellites and their dispenser, combined, weigh just under 10 metric tons and are bound for low-Earth orbit. A backup launch window is available on Saturday.

The first stage booster for this flight initially launched the Iridium-3 mission in October, 2017. SpaceX has not attempted a third flight of any of its boosters yet and won't do so until it debuts the latest version of its Falcon 9 rocket—the Block 5—later this spring. Therefore, the company will not attempt to recover this used first stage at sea after its flight Friday.

However, SpaceX is likely to try to successfully recover the rocket's payload fairings—valued at about $5 million to $6 million—for the first time. It came close to doing so during a launch attempt in February, but the payload fairing splashed down "a few hundred meters" away from the recovery ship. The ship, Mr. Steven, is again on the moveahead of Friday's launch attempt.

CRS-14

After the Iridium-5 launch, SpaceX's focus will move to the East Coast of the United States, where it is scheduled to attempt the launch from Florida on a space station supply mission on Monday, April 2, at 4:30pm ET. The Dragon spacecraft will carry 1.7 tons of pressurized cargo to the station, as well as 926kg of unpressurized cargo in its "trunk."

The first stage of this rocket, which previously flew during the 12th cargo supply mission last August, will probably not attempt a land-based landing. The booster underwent a successful static firing on Wednesday at Launch Pad 40, according to the company.

After these flights, SpaceX has a couple more missions planned for the month of April, including the launch of NASA’s Transiting Exoplanet Survey Satellite on April 16 and the Bangabandhu 1 communications satellite at the end of the month. The latter flight is much anticipated, as it should see the debut of the aforementioned Block 5 version of the Falcon 9 rocket.

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source:https://arstechnica.com/science/2018/03/spacex-has-a-busy-weekend-ahead-of-it/