NROL-101 - Atlas V 531 (AV-086) - CCAFS SLC-41 - 13.11.2020 22:32 UTC

[tnt22]

Nov 04, 2020 21:01

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]

Nov 04, 2020 21:07

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

[tnt22]

Nov 04, 2020 21:20

The Centaur liquid oxygen system preps have been performed to configure the ground LOX transfer system and ground pneumatic supply systems for filling the Centaur LOX tank and pressurizing the Centaur helium bottles for launch. Also, the Centaur liquid hydrogen system preps have configured the ground hydrogen transfer system for loading the Centaur hydrogen tank later in the countdown.

[tnt22]

Nov 04, 2020 21:28

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]

Nov 04, 2020 21:31

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

[tnt22]

Nov 04, 2020 21:39

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]

Nov 04, 2020 21:45

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

[tnt22]

Nov 04, 2020 21:59

The first weather balloon of the countdown is being launched. A series of balloons will be sent 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]

Nov 04, 2020 22:04

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 5:54 p.m. EST (2254 UTC).


Photo by United Launch Alliance

[tnt22]

Nov 04, 2020 22:07

Internal battery checks are beginning now.

[tnt22]

Nov 04, 2020 22:33

This is Atlas Launch Control at T-minus 2 hours, 51 minutes (L-3 hours, 21 minutes) and counting. Guidance system testing is complete.

[tnt22]

Nov 04, 2020 22:44

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]

Nov 04, 2020 23:08

Weather Remains 70% 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 a 70 percent chance of favorable conditions for today's opportunity, with the only concern being ground winds.

The launch time outlook calls for a few low and broken clouds, good visibility, east-northeasterly winds 22 to 26 knots and a temperature near 75 degrees F.

[tnt22]

Nov 04, 2020 23:12

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

[tnt22]

 United States Space Force @SpaceForceDoD 22 мин. назад

Watch as the Space Force logo is placed on @ulalaunch Atlas V rocket that will carry a payload for the @NatReconOfc on NROL-101 scheduled for today @ 5:54 p.m. EST. #SemperSupra

(0:46)

[tnt22]

Nov 04, 2020 23:16

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.

[tnt22]

Nov 04, 2020 23:21

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

[tnt22]

Nov 04, 2020 23:24

Countdown Holding

This is Atlas Launch Control at T-minus 2 hours (L-2 hours, 30 minutes) 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 15 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 15 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]

 Thomas Burghardt @TGMetsFan98 42 мин. назад

It's launch day in Florida! #ULA #AtlasV #NROL101

[tnt22]

Nov 04, 2020 23:36

Go for Fueling

A readiness poll of the launch team by Launch Conductor Scott Barney, with concurrence of ULA Launch Director Tom Heter III, has approved cryogenic tanking operations to begin once the countdown resumes.