Two SpaceX rockets stand on launch pads several miles apart on Florida’s Space Coast awaiting launch opportunities Thursday and Friday, once an often delayed Delta 4-Heavy rocket from rival United Launch Alliance is in able to take off from Cape Canaveral with a top secret US government spy satellite.
ULA has been trying to launch the Delta 4-Heavy rocket since late August, but a series of problems with the launch pad kept the heavy lift on the ground. The mission will deploy a classified payload in a geosynchronous orbit more than 22,000 miles (nearly 36,000 kilometers) above the Earth.
Delta 4-Heavy flight, with its homeland security payload likely worth more than $ 1 billion, took priority over the Space Force’s Eastern Range, which oversees the planning of launches from the pads of Cape Canaveral Air. Force Station and the nearby Kennedy Space Center.
A pressure regulator failed on the launch pad during the Delta 4 ignition sequence on August 29, prompting ULA to refurbish and retest the equipment before preparing for a launch attempt on Saturday, September 26. ULA has again delayed the mission to assess a problem with the swingarm hydraulic system at pad 37B, the launch pad of Delta 4 in Cape Canaveral.
Officials kicked off a countdown on Monday afternoon for a launch opportunity just after midnight on Tuesday. But the threat of lightning prevented ground crews from retracting the launch pad’s towering mobile gantry, which is needed to link the satellites in a vertical configuration on the platform and also provides protection for the rocket before launch.
On Tuesday, storms again delayed the rollback of the Mobile Service Tower, but the weather cleared in time for technicians to begin moving the gantry. Then a hydraulic leak interrupted the gantry rollback procedure, causing ULA to clean up another launch attempt.
ULA will begin its fifth countdown for Delta 4-Heavy mission – codenamed NROL-44 – on Wednesday afternoon. The clocks will be scheduled to tick down towards takeoff at 11:54 pm. EDT Wednesday (0354 GMT Thursday).
Analysts believe the payload aboard the Delta 4-Heavy is a signal intelligence satellite with a giant deployable antenna designed to intercept voice and data traffic from US adversaries.
Several SpaceX missions have been delayed by the ever-changing Delta 4-Heavy launch dates. The launch of a Falcon 9 with Argentina’s SAOCOM 1B radar observation satellite was delayed for a month in August due to concerns about the rocket’s flight path near the Delta 4 platform, where the NRO’s high-value payload is was located above the ULA rocket.
The SAOCOM 1B satellite was finally cleared for flight on Aug.30 after military officials apparently gave up their concerns following the Delta 4-Heavy’s last-minute disruption on Aug.29.
A Falcon 9 rocket and a navigation satellite from the US Space Force’s global positioning system were due to ascend Tuesday night from Pad 40 at Cape Canaveral Air Force Station. But SpaceX delayed the GPS mission this week in response to canceled Delta 4-Heavy launch attempts.
SpaceX initially rescheduled its GPS launch for Wednesday night after Delta 4 was delayed to Tuesday. After the Delta 4-Heavy scrub on Tuesday, SpaceX announced that the GPS launch would be postponed until Friday, when a 15-minute launch window will be available at 9:43 pm. EDT (0143 GMT Saturday).
The Falcon 9 will point to an elliptical orbit to release Lockheed Martin’s GPS 3 SV04 navigation satellite. The spacecraft will then move in a circular orbit 12,550 miles (20,200 kilometers) above the Earth to enter the GPS constellation providing positioning, navigation and timing services around the world.
The launch of SpaceX’s next 60 Starlink broadband satellites was also impacted by the shuffling program in the Cape Canaveral range.
The 60 Starlink satellites are flattened above a Falcon 9 rocket at Pad 39A, located at NASA’s Kennedy Space Center, a few miles north of Pad 40 and Pad 37B. SpaceX tried to launch the Starlink mission on Monday morning, but canceled the countdown less than a minute before takeoff due to unfavorable weather.
SpaceX plans to retry launching the next 60 Starlink satellites on Thursday at 9:17 am EDT (1317 GMT). The Falcon 9 rocket will aim to carry the 60 quarter-tonne Internet satellites in a low-altitude orbit on the way to the operational orbit 341 miles (550 kilometers) above Earth.
SpaceX has two maritime landing platforms in the Atlantic Ocean several hundred miles northeast of Cape Canaveral for the recovery of first-stage reusable repeaters in GPS and Starlink missions.
The ever-changing launch program on Florida’s Space Coast has been dizzying for space enthusiasts, space journalists and other observers. Michael Ellis, space launch division director for national security at SpaceX, said last week that it can be stressful for launch teams as well.
“These things happen. We are quite used to the whiplash effect of new information arriving,” Ellis said in a conference call with reporters Friday. “We are able to manage it because we have such a strong partnership (with the range) and communication is transparent.
“I would be lying if I told you that sometimes it is not stressful, but up to this point we have two pads. We have dedicated teams to support simultaneous operations and we are able, thanks to our partnership, to work side by side with the Space Force.”
Brig. General Doug Schiess, commander of the 45th Space Wing who oversees range operations at Cape Canaveral, said on Friday that the range has improved its ability to handle the accelerated pace of launches.
“I’ve been in the launch business for quite some time and for the most part I was keeping things to ourselves,” Schiess said. “Recently, we’ve done a lot of work where we’re all in the same room together – ULA, SpaceX and eventually others as they come into the Eastern range – and we try to work through the program.”
The introduction of autonomous flight safety systems has helped safety officials reduce the time needed between launches. Autonomous safety systems allow rockets to automatically terminate their flights if they fly off course, replacing destruction systems that rely on manual command from a remote safety officer.
SpaceX’s Falcon 9 rockets use autonomous safety systems. ULA’s Atlas 5 and Delta 4 rockets still use the old flight termination system design, but will transition to an automated design with the next-generation Vulcan Centaur rocket.
Because the military considers the NROL-44 payload of critical importance, the 45th Space Wing offers the Delta 4-Heavy three launch opportunities at a time. Most missions only receive two dates, a primary and backup opportunity, before having to submit a new request to the range.
“Since Delta 4 had a launch date with two backups due to its importance, in the past we would not have given SpaceX the opportunity to launch (on one of the backup dates),” Schiess said.
Now the range offers SpaceX the opportunity to set a date on a Delta 4 backup date. The launch opportunity is therefore contingent upon the actual launch of the Delta 4, or at least the delay long enough to clear the road.
“I think it’s part of that collaboration, with the caveat that, ‘Hey, you can have this (date), but if that doesn’t work out, we’ll have to do something else,” Schiess said. “In the past we wouldn’t have done that. We would have said those three days are for Delta 4-Heavy, and you’ll have to wait. So I think it’s part of that collaboration that we’re really trying to work to be able to seize as many opportunities as possible. “
Ellis said SpaceX also prioritizes homeland security missions, such as the GPS launch, on its internal poster when deciding when to find slots for the company’s Starlink launches.
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