The United Launch Alliance will try again on Thursday to launch the Delta 4-heavy rocket and a classified spy satellite of the U.S. government after a three-month delay due to uninterrupted problems with the mission’s launch pad.
The mission will start from Florida’s newly renamed Cape Canaveral Space Force Station on Thursday evening at 3:15 p.m. EST (2315 GMT) on Pad 37B. Forecasters forecast near-ideal weather with a 90% chance of favorable conditions during the launch window on Thursday evening.
The Florida launch base, formerly known as Cape Canaveral Air Force Station, was officially named Wednesday during a visit by Vice President Mike Pence. The nearby Patrick Air Force Base was also renamed Patrick Space Force Base.
The new names reflect the next step in the evolution of the U.S. Air Force, which was established about a year ago to manage most of the Air Force’s space.
The Delta 4-heavy rocket will be launched into a top secret pay-load orbit for the US government’s spy satellite agency National Reconnaissance Office. The mission has been named NRL-44.
ULA, a 50-50 joint venture between Boeing and Lockheed Martin, first attempted to launch the Delta 4-heavy rocket in late August.
The actual launch date of the launch company for the NRL-44 mission is 2. It was August. A pneumatics issue prevented the rocket from launching on August 2, and the countdown ended on August 29, when the automatic launch sequence detected a problem with a pressure regulator. Launch pad designed for helium gas flow to spill the center engine of the rocket for launch.
The center does not open the controller for the engine, telling the computer controller at the countdown to stop you from counting during the engine start-up.
Bruno said engineers have repeatedly tested and tested three pressure flow devices on the Pad 37B before continuing another launch effort.
The URL was scheduled for Sept. 26 to attempt the next launch of the NRL-44 mission, but officials again delayed the mission to investigate concerns about the swing arm retraction system at the launch complex off Cape Canaveral off the coast of Delta 4-Heavy. The swing arms, which feed liquid propellants and air-conditioned air into the car, are designed to move quickly off the lift off rocket.
Bad weather and a hydraulic leak in the hardware associated with the launch pad’s mobile gantry forced ULA officials to halt a pair of launch efforts in late September.
On September 30, just before the main engines in the rocket’s three hydrogen-fueled RS-68s were ignited, the R-T minus was stopped at 7 seconds.
While solving this problem, the ULA faced a deeper problem with swing weapons on the 37 pad. The three swing arms feeding propellant and the air-conditioned air in the rocket and its satellite payload are designed to withdraw due to the delta 4-heavy lifting shutdown.
ULA President and CEO Tori Bruno tweeted that the technicians extracted 2,000 gallons of oil from the hydraulic swing arm retraction system. Bruno tweeted that the system had replaced several dozen valves and “several important items” before recharging the system with new hydraulic fluid.
“The success of the mission is a priority,” he added.
Frequent problems with various parts of the Delta 4-heavy launch pad have raised questions about the twisted infrastructure on the Pad 37B, originally built to support Saturn rocket launches in the 1960s, then Boeing landed in the 1990s until it took advantage. led delta 4 program.
Boeing built a huge mobile gantry for the Delta 4 rocket with a newly-stationed sailor with three huge retractable swing weapons.
The ULA is retiring the Delta 4 rocket family after five more launches – three more from Cape Canaveral in California and two frames from Vandenberg Air Force Base. The company’s next-generation Vulcan Centaur rocket, scheduled for launch in the second half of next year, will replace ULA’s existing Delta 4 and Atlas 5 launch vehicles.
While SpaceX’s Falcon Heavy rocket is relatively inexpensive and can carry heavy payloads in low orbit, Delta 4-Heavy has demonstrated the ability to inject satellites directly into high-altitude circular geosynchronous orbits more than 22,000 miles (about 36,000 kilometers) above Earth.
The techniques required for such orbital injections take more than six hours. Although the payload of the NRL-44 mission has been classified, independent analysts say the rocket’s capabilities, its launch azimuth and the launch window are publicly known as parameters known to be ready to carry a signal spy satellite in Delta 4-heavy geosynchronous orbit.
In this orbit, the satellite is expected to spread a huge football field-sized antenna to listen to telephone calls and other data traffic from U.S. opponents.
The Delta Four-Heavy also has larger payload fairs than the Falcon Heavy, and mobile shelters in Cape Canaveral and Wendenberg allow ground crews to maneuver satellites on the rocket with vertical positions. SpaceX may support future national security missions that currently only operate on Delta 4-heavy aircraft, with Falcon Heavy offering an increased pay-load shroud and plans to build a vertical integrated hangar at the Kennedy Space Center.
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