Perseverance (Mars 2020 rover) - Atlas V 541 - Canaveral SLC-41 - 30.07.2020

[tnt22]

Jul 30, 2020 09:25

The flight control operational test is getting underway. This test will validate the control functions on the Atlas first stage main engine and the Centaur upper stage by confirming that valves cycle properly and that the engine steering systems perform as commanded.

[tnt22]

Jul 30, 2020 09:30

First stage propulsion and hydraulic preps have been completed. The propulsion preps configured the ground liquid oxygen transfer system and ground pneumatic supply systems for filling the Atlas first stage LOX tank and pressurizing the Atlas helium bottles for launch. The hydraulic preps configured the ground hydraulic pressure unit to provide for first stage main engine pre-launch hydraulic control.

[tnt22]

Jul 30, 2020 09:32

An open-loop test of the S-band system used to relay telemetry from the launch vehicle during flight is underway.

[tnt22]

Jul 30, 2020 09:40

The main engine nozzles are gimbaling for a steering test of the vehicle's flight controls.


Photo by United Launch Alliance

[tnt22]

Jul 30, 2020 09:50

The cover atop the launch pad's flame bucket is being removed.

[tnt22]

Jul 30, 2020 09:55

Antenna checks are being performed to verify functionality of the GPS Metric Tracking system. GPS MT is the system that uses the orbiting Global Positioning System navigation satellite constellation to track the rocket's flight downrange with position, velocity and timing information.

[tnt22]

Jul 30, 2020 10:31

We are now three hours into the countdown and working no significant issues here in the Atlas Spaceflight Operations Center (ASOC) or at the Space Launch Complex-41 pad. Liftoff remains scheduled for 7:50 a.m. EDT (1150 UTC).


Photo by United Launch Alliance

[tnt22]

Jul 30, 2020 10:35

Internal battery checks are beginning now

[tnt22]

 Tory Bruno @torybruno 7 мин. назад

The #MarsPerseverance launch crew is on station. Mighty Atlas is looking good. Weather is holding at Pgo 80%. The board is green. Seems like a good day to go to another planet

[tnt22]

Jul 30, 2020 10:55

The first weather balloon of the countdown has been launched. A series of balloons will be set aloft over the next few hours to measure the speed and direction of upper level winds that the Atlas V will experience during flight.

[tnt22]

Jul 30, 2020 11:00

The initiation of gaseous nitrogen flow to the launch vehicle has started. This changes the environmental control system (ECS) to supply nitrogen gas rather than conditioned air to the internal compartments of the Atlas V and the payload fairing in preparation for fueling and launch.

[tnt22]

Источник

[tnt22]

Jul 30, 2020 11:35

Weather Remains 80% GO

In the pre-fueling weather briefing to mission management, Launch Weather Officer Jessica Williams reports that conditions remain favorable at Cape Canaveral for a rocket countdown. There are no weather constraints against proceeding into Atlas V fueling operations as scheduled.

The launch forecast remains unchanged at an 80 percent chance of favorable conditions during the window, with the only concerns being clouds.

The launch time outlook calls for a few low and scattered mid-level clouds, southerly winds 6 to 8 knots and a temperature near 80 degrees F.

[tnt22]

Jul 30, 2020 11:37

The launch pad crew has completed its hands-on work to ready Space Launch Complex-41 for today's mission, and Launch Conductor Scott Barney has given the instruction for personnel to depart the site in advance of fueling operations.


Photo by United Launch Alliance

[tnt22]

Jul 30, 2020 11:38

Hold-fire checks are being conducted at this time. This verifies the circuitry used to stop the countdown if a safety concern arises.

[tnt22]

Jul 30, 2020 11:50

Countdown Holding

This is Atlas Launch Control at T-minus 2 hours (L-3 hours) and holding. The countdown has entered the first of two planned, built-in holds that are scheduled in today's timeline. This first block of time, lasting 30 minutes, gives the countdown some margin to resolve issues or catch up work that could be running late, and the hold provides an opportunity to ensure all is ready before fueling operations begin.

The final hold, also lasting 30 minutes, occurs at T-minus 4 minutes.

At the present time, all activities are on schedule and no problems are being addressed by the launch team.

[tnt22]

Jul 30, 2020 11:51

The hazard area around the launch site has been cleared of all personnel for fueling and liftoff.

[tnt22]

Jul 30, 2020 11:55

Safety officials have confirmed that there is just one Collision Avoidance (COLA) period during today's 120-minute launch window at 9:40 a.m. EDT. COLAs are brief moments in time when the launch is not allowed to occur because the trajectory would pass too close to another object already in space. This analysis is based on a screening of known active and debris objects in orbit that could cause a conjunction with the ascending Atlas V and Perseverance.

[tnt22]

Jul 30, 2020 12:00

This is Atlas Launch Control at T-minus 2 hours and holding, with 20 minutes remaining in this built-in hold.

The Atlas V rocket will be loaded with approximately 66,000 gallons of liquid oxygen and liquid hydrogen once the countdown resumes.

The first stage was loaded with 25,000 gallons of RP-1 kerosene during the WDR countdown dress rehearsal last month.

The first stage will propel Perseverance out of Earth's atmosphere and the Centaur will execute two sequential burns to put Mars 2020 on the flight path to the red planet.

[tnt22]

Jul 30, 2020 12:05

The call to stations for cryogenic tanking has been announced to all console operators here in the control room. A readiness poll for fueling will occur at 5:17 a.m. EDT.