SpaceX tested a Falcon 9 rocket on Cape Canaveral on Saturday night, clearing the way for a delayed lift with the Israeli-owned Amos 17 commercial communications satellite as soon as Tuesday, provided SpaceX can work its way into a busy form ahead of a previously scheduled Atlas 5 launch this week on the U.S. Air Force's eastern range.
After completing a ridiculous countdown, Falcon 9's nine Merlin 1D first-stage engines ignited for several seconds at 23:30 EDT Saturday (0330 GMT Sunday) at Cape Canaveral's Complex 40 launch pad holding clamps holding the rocket to the ground .
SpaceX said in a tweet that the team is targeting the launch of the Amos 17 satellite on the Falcon 9 rocket as soon as Tuesday night, "pending availability level."
An Atlas 5 rocket owned by United Launch Alliance, a SpaceX rival in the launch market, has already been booked on the Air Force to be launched on Thursday morning from neighboring Cushion 41, more than a mile north of SpaceX's Cushion 40.
SpaceX previously reserved launch attempts Saturday and Sunday in the Eastern range, but the company bypassed these launch opportunities to solve a technical problem.
The Falcon 9 launch delay sets up the possibility of departure from Cape Canaveral on Tuesday, separated by less than 36 hours. Officials from the Air Force's 45th Space Shuttle, which oversees the shooting range at Cape Canaveral, said last year the military unit could hold two missions in 24 hours, thanks to recent technology upgrades.
One of the primary changes that allow rapid launch of turnaround operations in range is the introduction of the autonomous flight termination system, which will be able to destroy a rocket if it flies off course. Area security teams are now also tracking rockets fired from Cape Canaveral using GPS satellite data, rather than relying on ground-based radars.
The Eastern Range consists of a network of communications, tracking and security installations used at every launch from Florida's Space Coast. The series typically works on a first come, first served basis.
Assuming the trial can continue on Tuesday, lifting the Falcon 9 rocket with Amos 17 is scheduled for a launch window that opens at 6:52 p.m. EDT (2252 GMT) and extends to 20:20 p.m. EDT (0020 GMT).
Atlas 5's two-hour launch window on Thursday opens at 05:44 EDT (0944 GMT).
The Atlas 5 rocket will launch the Air Force's Fifth Advanced Extremely High Frequency, or AEHF, communications satellite to join a fleet of geostationary spacecraft providing secure voice, video and data connections between US government and military commanders.
The Lockheed Martin-built AEHF satellites each cost more than $ 1 billion, forming the backbone of the military's protected satellite communications infrastructure, which the Air Force says is resistant to jamming, cyberattacks and nuclear war.
The Atlas 5 rocket, which was scheduled to launch the AEHF 5 satellite, is scheduled to roll out of its vertical hangar on tamp 41 on Tuesday morning. When the starter is on the ropes, the ground crews will connect the Atlas 5 to electrical, data and propulsion preparations for the start of the countdown on Wednesday night.
Officials raised the possibility of rapid fire of Falcon 9 and Atlas 5 from pads 40 and 41 last year when SpaceX launched a Spanish communications satellite the same week as a new NOAA GOES geostationary weather observatory awaited a ULA rocket.
Atlas 5 and Falcon 9 pads at Cape Canaveral both have a "clean cushion" design with no protective building to provide rocket shelter after rolling out in preparation for lifting.
The Air Force was originally prepared to support Atlas 5 and Falcon 9 launches last year only 16 and a half hours apart.
Although the Falcon 9 cushion is more than a mile away from the Atlas facility, ULA and NASA officials responsible for launching the NOAA weather satellite were concerned about the Atlas 5 rock and sensitive optics on GOE's meteorological payload would be exposed to Falcon 9's exhaust pipes when it fired into space.
Officials also studied whether Atlas 5 and the GOES-S weather satellite may be threatened by a potential accident during Falcon 9 launch.
In that case, the SpaceX launch was eventually delayed after the Atlas 5 rocket lifted off with the GOES weather satellite.
The air defense leaders in charge of the eastern area and the AEHF satellite will make final determinations in the week's launch plan. A review of the readiness assessment for the Atlas 5 mission is scheduled for Monday morning.
The Saturday shooting was the second for the Falcon 9 rocket in the Amos 17 launch campaign, following a test shooting on Wednesday night. SpaceX decided to replace a valve after the hotfire test on Wednesday night, and completed another fuel and engine test on Saturday.
Crew crew planned to remove the Falcon 9 rocket from the launch on Sunday and return it to a hangar south of Cushion 40 for attachment of the spacecraft Amos 17, already encapsulated inside the payload screen.
The Boeing-built Amos 17 satellite is owned by Spacecom Ltd., an Israeli company based in Tel Aviv. The last time a Spacecom-owned satellite was to launch on a SpaceX rocket, the spacecraft was destroyed during an explosion minutes before a scheduled static fire test.
Since that accident, SpaceX has not placed one of the customer's payload on the static fire test rocket.
The official weather forecast suggests that SpaceX's support team will battle stormy conditions during a possible countdown on Tuesday. There is a 60 percent chance of weather conditions that would be unacceptable for a shooting Tuesday night, according to a U.S. view. Air Force & # 39; s 45th Weather Squadron.
The main weather concerns Tuesday are with lightning and thick cloud rules. The forecast does not list a backup option for Amos 17, presumably because the Air Force area would not be able to support a countdown Wednesday in the hours before the Atlas 5 launch.
“Thunderstorms will affect the Space Coast most of the afternoon. and early evening hours, which means a higher potential for weather violations at the beginning of the window, ”forecasters wrote Sunday. "But as the sun goes down and thunderstorms diminish in coverage, we will likely see improved launch potential through the latter half of the launch window."
The Falcon 9 rocket launched with Amos 17 will fly in consumer mode without landing legs. The heavy weight of Amos 17, at approximately 6.5 tonnes (14,330 pounds) fully powered, requires all of the Falcon 9's lifting ability to deliver it to a geostationary transmission path extending more than 22,000 miles (nearly 36,000 kilometers) across the equator.  This will be the second time SpaceXs has flown one of the Falcon 9 rockets in the new generation "Block 5" configuration without trying to recover the first stage.
The booster launch with Amos 17 flew earlier twice from Cape Canaveral last year sent communications satellites Telstar 19 VANTAGE and Es & # 39; hail 2 toward orbit, then returned to landings on SpaceX's Atlantic drone ship for refurbishment and reuse.
Amos 17 will use its own engine to circulate its orbit more than 22,000 miles above the equator, where it will park at 17 degrees east longitude. In geostationary orbit, Amos 17's orbital velocity will match the rotation of the Earth, giving the satellite a fixed geographical coverage area over sub-Saharan Africa, Europe, Asia and the Middle East.
Spacecom states that Amos 17 is designed for a 20-year lifespan, and the mission costs around $ 250 million, including spacecraft, launch services and insurance.
Pollack, Spacecom's President and CEO. "Amos's 17 launch is a meaningful and strategic milestone that enhances Israel's continued presence in space and our business growth."
Amos 17 will replace the Amos 5 satellite 17 degrees east, which failed in 2015. The new satellite has C-band, Ku-band and Ka-band communication payload to provide TV broadcasts, broadband Internet and other networks and data relay services.
Spacecom purchased the Amos 17 satellite in 2016 from Boeing under a $ 161 million contract.
The launch of Amos 17 will be the 10th flight of SpaceX's Falcon rocket family this year.  Email the author.
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