GPS III SV02 "Magellan" - Delta-IV-M+(4,2) [D-384] - CCAFS, SLC-37B - 22.07.2019, 13:06 UTC

Автор tnt22, 25.03.2019 21:58:33

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tnt22

ЦитироватьAug 22 09:52
The S-band system has been tested. This will be used for telemetry downlink during the flight.

Also, the internal battery checks have been completed.

tnt22

ЦитироватьAug 22 10:09
The initiation of gaseous nitrogen flow to the payload fairing is starting. This changes the environmental control systems to supply conditioned nitrogen gas rather than air to the rocket in preparation for the cryogenic fueling and in-flight environments.

tnt22

ЦитироватьAug 22 10:27
Hold-fire checks were complete satisfactorily. Also, guidance system testing is complete.

tnt22

ЦитироватьAug 22 10:33
The environmental control system changeover from air to gaseous nitrogen for the launch vehicle has started. This supplies conditioned nitrogen gas to internal compartments of the Delta IV rocket.

tnt22

ЦитироватьAug 22 10:36
Weather is GO for fueling

This is Delta Launch Control at T-minus 4 hours, 24 minutes (L-5 hours, 24 minutes) and counting. In the pre-fueling weather briefing, conditions at Cape Canaveral are acceptable for proceeding into cryogenic tanking operations at Space Launch Complex-37.

Launch Weather Officer Will Ulrich from the Air Force's 45th Weather Squadron also reports that the weather outlook remains favorable for the flight of Delta IV and GPS III SV02 this morning. The forecast calls for an 80 percent chance of allowable liftoff conditions, with just scattered clouds, good visibility, easterly winds peaking to 10 knots and a temperature of near 83 degrees F.

The only concern is cumulus clouds from any showers that develop offshore.

All rules are green and "go" at the present time.

tnt22

ЦитироватьAug 22 10:41
Clear the complex

The launch pad crew has completed its hands-on work to ready Space Launch Complex-37 for today's mission, and the launch conductor has given the instruction for personnel to depart the site in advance of fueling operations.

tnt22

ЦитироватьAug 22 10:45
Countdown holding

This is Delta Launch Control at T-minus 4 hours, 15 minutes and holding. The countdown has entered the first of two planned, built-in holds that are scheduled in today's timeline. Each is 30-minute blocks of time that gives the countdown some margin to resolve issues or catch up on work could be running behind.

This particular hold serves as a margin before fueling operations begin. At the present time, however, all activities are progressing well and no significant problems are being addressed by the launch team.

The final hold occurs at T-minus 4 minutes.

tnt22

ЦитироватьAug 22 11:13
GO for fueling

A readiness poll of the launch team by Launch Conductor Dillon Rice, with concurrence of ULA Launch Director Paul Aragon, has authorized cryogenic tanking operations to begin as the countdown continues this morning. The Delta IV rocket will be loaded with approximately 165,000 gallons of liquid oxygen and liquid hydrogen over the next couple of hours.

tnt22

ЦитироватьAug 22 11:16
Countdown resumes

This is Delta Launch Control at T-minus 4 hours, 15 minutes and counting. The next phase of today's launch countdown has been initiated for liftoff of the United Launch Alliance Delta IV rocket for today's satellite-delivery flight of GPS III SV02.

Preparatory steps for fueling are being kicked off, including liquid hydrogen storage tank pressurization and charging the high-pressure helium bottles on the common booster core and second stage.

tnt22

https://spaceflightnow.com/2019/08/22/ulas-last-delta-4-medium-rocket-set-for-launch-thursday/
ЦитироватьULA's last Delta 4-Medium rocket set for launch Thursday
August 22, 2019 | Stephen Clark


A United Launch Alliance Delta 4-Medium rocket, fitted with two solid rocket boosters, stands ready for launch Thursday at Cape Canaveral's Complex 37 launch pad. Credit: United Launch Alliance

United Launch Alliance is set to retire part of its rocket family Thursday with the final flight of the Delta 4 rocket's "single stick" configuration, a mission set for liftoff fr om Cape Canaveral carrying a new GPS navigation satellite into orbit for the U.S. Air Force.

The Delta 4-Medium's 29th and last flight is scheduled for takeoff fr om Cape Canaveral's Complex 37 launch pad at 9:00:30 a.m. EDT (1300:30 GMT) Thursday. The launch window extends until 9:27 a.m. EDT.

There is an 80 percent chance of favorable weather for Thursday's launch window.

ULA is phasing out the Delta 4-Medium as the company faces stiff competition from SpaceX for U.S. military launch contracts. The new Vulcan Centaur rocket, set for an inaugural launch in 2021, will be less expensive than than the Atlas and Delta rockets it will replace, according to ULA.

The Delta 4-Heavy rocket, made by combining three Delta 4 first stage cores together, will continue flying through 2023. ULA's Atlas 5 rockets, which are less expensive than the Delta 4, will also remain operational through the early-to-mid 2020s.

"We made a business decision a few years ago that we would transition from the Delta 4 and Atlas vehicles over to a Vulcan Centaur, purpose-built to satisfy the entire mission suite, so it was time for us to phase out the Delta 4-Medium at this point,: said Gary Wentz, ULA's vice president of government and commercial programs, in a pre-launch press briefing. "We don't see any specific payloads that would require the Delta 4-Medium that we can't fly on an Atlas 5."

The Delta 4 launcher was originally designed and developed by Boeing. The Atlas 5 was conceived by Lockheed Martin.

The competing aerospace contractors merged their launch divisions in 2006, marking the birth of ULA as a 50-50 joint venture.

ULA's launch team will load super-cold liquid hydrogen and liquid oxygen into the two-stage Delta 4 rocket during Thursday morning's countdown.

The cryogenic propellants will feed the first stage's RS-68A main engine and the second stage's RL10 engine. Both powerplants are produced by Aerojet Rocketdyne.

The Delta 4 launching Thursday will fly in the "4,2" configuration with a 4-meter (13.1-foot-diameter) payload fairing and two strap-on solid rocket boosters built by Northrop Grumman Innovation Systems.


Thursday's launch will mark the final flight of a Delta 4-Medium rocket. ULA plans at least five more Delta 4-Heavy missions, using the configuration on the right side of this chart with three first stage booster cores. Credit: United Launch Alliance
The RS-68A core engine will ignite at T-minus 5 seconds and throttle up for a computer-run health check. Assuming all systems are ready, the side-mounted solid-fueled boosters will fire when the countdown clock reaches zero to push the Delta 4 into the sky.

The main engine and solid rocket boosters will generate 1.1 million pounds of combined thrust. Vectoring nozzles on the RS-68A engine and twin strap-on motors will steer the Delta 4 on a northeasterly trajectory roughly parallel to the U.S. East Coast.

The launcher will surpass the speed of sound in less than a minute, and the two 53-foot-long (16-meter) solid rocket boosters will burn out and jettison at T+plus 1 minute, 40 seconds.

The RS-68 core stage engine will shut down at T+plus 3 minutes, 55 seconds, followed by stage separation roughly seven seconds later. An RL10 engine on the Delta's upper stage, also built by Aerojet Rocketdyne, will ignite for the first of two firings required to place the GPS satellite into an elliptical transfer orbit.

The Delta 4's payload fairing will jettison in a clamshell-like fashion at T+plus 4 minutes, 26 seconds, once the rocket soars into the rarefied upper atmosphere. The shroud protects the GPS payload during launch preparations and the ascent through the lower layers of the atmosphere.

The RL10 upper stage engine will switch off at T+plus 13 minutes, 33 seconds to reach a preliminary orbit. Restart of the RL10 engine is planned nearly 67 minutes after liftoff for a three-and-a-half-minute burn to inject the GPS spacecraft into an egg-shaped transfer orbit ranging between 745 miles (1,200 kilometers) and 12,542 miles (20,185 kilometers) above Earth, with its orbital plane tilted 55 degrees to the equator.

The Lockheed Martin-built GPS satellite will separate from the Delta 4 launcher at T+plus 1 hour, 55 minutes.
[свернуть]
The GPS 3 SV02 navigation satellite, nicknamed "Magellan," will use its own engine to circularize its orbit and join the GPS constellation some 12,550 miles above the planet, wh ere ground teams will test the new spacecraft and put it into service to replace an aging member of the constellation.

The GPS network provides positioning and timing services worldwide for military and civilian users, beaming signals relied upon by airliners, ATMs, drivers and smart bombs, among numerous other users.

"We're committed to maintaining GPS as the gold standard of positioning, navigation and timing for all other systems to be measured against," said Lt. Col. Maggie Sullivan, the Air Force's GPS 3 program manager.

Thirty-one satellites are currently providing GPS navigation services.

The satellite set for launch Thursday is the second in a new generation of GPS satellites, providing more accurate navigation signals and boasting longer design lifetimes. The new GPS 3 satellites provide a new L1C civilian signal that is compatible with Europe's Galileo network.

Other space-based navigation networks operated by Japan and China are also adopting similar compatible signals.


The GPS 3 SV02 navigation satellite, nicknamed "Magellan," was encapsulated inside the Delta 4 rocket's payload fairing in late June. Credit: Lockheed Martin

"Compared to the satellites in today's constellation, this next generation of GPS satellites have three times greater accuracy, eight times improved anti-jam capabilities, and the new L1C civil signal compatible with other international satellite navigation systems like Galileo," said Johnathon Caldwell, Lockheed Martin's vice president of navigation systems.

"For those user equipment (providers) who elect to incorporate the L1C civil signal into their chipsets, those users will now have access not just to the GPS constellation but to Galileo and others who choose to then follow on with the L1C civil signal implementation," Caldwell said. "So for users who are authorized to do that, instead of having just the legacy 31 points in the sky that you get from GPS, you'll add on to it the ever-growing Galileo constellation.

"When it comes to finding out wh ere you are, the more satellites you can see the better your position is."

The first GPS 3-series satellite, named GPS 3 SV01, completed its post-launch checkout July 12 following an on-target deployment by a SpaceX Falcon 9 rocket last December, officials said. More testing is planned before GPS 3 SV01, named "Vespucci," is ready to join the active GPS network.

"We're excited now that the vehicle is through its on-orbit checkout and moving into the next phase of operational testing," Caldwell said. "We expect that to begin later this year, and we're looking forward to officially handing over the vehicle to the Air Force."

Like the previous line of Boeing-built GPS 2F satellites, the GPS 3-series spacecraft will broadcast a dedicated L5 signal geared to support air navigation. The GPS 3 satellites also continue beaming an encrypted military-grade navigation signal known as M-code.

The M-code signal allows GPS satellites to broadcast higher-power, jam-resistant signals over specific regions, such as a military theater or battlefield. The capability provides U.S. and allied forces with more reliable navigation services, and could also allow the military to intentionally disrupt or jam civilian-grade GPS signals in a particular region, while the M-code signal remains unimpeded.

L3Harris Technologies builds the navigation payloads for the GPS 3 satellites.
[свернуть]
Thursday's launch is timed to place the GPS 3 SV02 spacecraft into Plane D, Slot 3 of the GPS constellation. That position is currently occupied by a GPS satellite launched in March 2003. Sullivan said the Air Force will make an "operational decision" on which aging GPS satellite, presumably in Plane D, the new spacecraft will replace.

The GPS satellites are spread among six orbital planes, each with four primary spacecraft, plus spares.

According to Sullivan, the GPS 3 SV02 spacecraft cost around $500 million. Future GPS 3 satellites will cost less, and officials target a cost of less than $200 million per spacecraft by time GPS 3 SV10 is ready for launch.

"The great thing about GPS is the volume of satellites," Caldwell said. "You gain tremendous efficiencies when you have production volume, and you get commensurate cost reduction."

Lockheed Martin is on contract with the Air Force to build up to 32 satellites, including 10 GPS 3 spacecraft and 22 upgraded GPS 3F satellites.

The next GPS mission, designated GPS 3 SV03 and nicknamed "Columbus," is set for launch on a SpaceX Falcon 9 rocket in January. The satellite for that mission has already been declared available for launch, Air Force officials said.

tnt22

ЦитироватьAug 22 11:28
The flight control operator is performing the ECU BIT test on the Delta IV rocket's first stage. This is the built-in test (BIT) of the engine control unit (ECU) that cycles hydraulically-actuated engine valves prior to the start of fueling operations.

tnt22

ЦитироватьAug 22 11:43
Chilldown begins

A "go" has been given to start the cold gas chilldown conditioning of the liquid hydrogen system on the common booster core. This is the precursor step before filling the first stage with propellant.

The common booster core will be loaded with 110,000 gallons of super-cold liquid hydrogen that is chilled to minus-423 degrees Fahrenheit. The liquid hydrogen, along with the liquid oxygen to be loaded shortly, will be consumed by the RS-68A main engine.

tnt22


tnt22

ЦитироватьAug 22 11:50
The 165,000 gallons of cryogenic liquid hydrogen and liquid oxygen that will fill the Delta IV rocket amounts to 150,000 gallons on the first stage and 15,000 gallons on the second stage. The first stage does the heavy-lifting in the initial four minutes of flight to exit Earth's atmosphere. The second stage will perform a pair of burns to achieve and then shape the orbit, delivering GPS III SV02 into its targeted transfer orbit.

A third and final burn about 35 minutes after payload deployment will serve as a de-orbit burn to dispose of the spent rocket body.

tnt22

ЦитироватьAug 22 12:12
CBC LH2 loading begins

This is Delta Launch Control at T-minus 3 hours, 18 minutes and counting. The cold gas chilldown conditioning of the common booster core's liquid hydrogen system has been accomplished, clearing the way to begin propellant loading in "slow-fill" mode. That will transition to "fast-fill" after a small portion of the tank is loaded.

FUEL1 console operator Manny Marinas is overseeing the CBC LH2 loading today.

tnt22

ЦитироватьAug 22 12:33
The fueling specialists in the launch control center are standing by while engineers assess ground software before proceeding further into tanking.


Aug 22 12:39
The countdown clock is proceeding and there is available margin in the timeline to make up for this pause in fueling operations while still making our launch window today.

tnt22

ЦитироватьAug 22 13:04
Anomaly Chief Steve Huff in the Delta Operations Center has reported that engineers have completed the ground software review and the team recommends proceeding with the the countdown and fueling operations.

tnt22

ЦитироватьAug 22 13:26
CBC LOX loading begins

This is Delta Launch Control. The liquid oxygen chilldown is complete for the booster core, allowing 40,000 gallons of super-cold LOX to begin transferring into the rocket for today's launch under the control of LOX1 console operator Jim Wheble.

tnt22

ЦитироватьAug 22 13:27
Some approaching rain showers east of Cape Canaveral may cause a red condition shortly on the launch weather status board. However, Launch Weather Officer Will Ulrich is optimistic that constraint will clear in time for the launch window.

tnt22

ЦитироватьAug 22 13:40
DCSS LH2 loading begins

The next step in fuel operations is getting underway by loading 10,000 gallons of liquid hydrogen into the Delta Cryogenic Second Stage following completion of that system's chilldown.

The stage receives its fuel from the launch pad's middle swing arm that extends from the Fixed Umbilical Tower to the Delta IV rocket.

FUEL2 console operator Giavanna Piccirilli oversees second stage liquid hydrogen.