WGS-9 – Delta IV-M+(5,4) – Канаверал SLC-37B – 19.03.2017 – 00:18 UTC

[tnt22]

03/19/2017 01:55

Following topping, the propellant conditioning has been achieved for all four cryo tanks on the vehicle.

[tnt22]

03/19/2017 01:58  L-45 minutes and counting

Now 45 minutes till launch! Weather remains acceptable and no technical issues being worked with the rocket for the targeted liftoff at 7:44 p.m. EDT (2344 GMT). It is a very quiet countdown today.

A reminder that if you will be away from your computer but would like to receive occasional countdown updates, sign up for our Twitter feed to get text message updates on your cellphone. U.S. readers can also sign up from their phone by texting "follow spaceflightnow" to 40404. (Standard text messaging charges apply.)

[tnt22]

Spaceflight101 LIVE‏ @S101_Live 2 мин. назад
 
Final activities prior to terminal count include propellant conditioning, flight software load, ordnance arming & final satellite preps.

[tnt22]

Spaceflight101 LIVE‏ @S101_Live 39 сек. назад
 
The Launch Team is beginning final preparations for the Automated Countdown now. RF Link Checks & FTS tests are complete. #WGS9

[tnt22]

03/19/2017 02:07
T-minus 6 minutes. Standing by to go into the hold.

[tnt22]

03/19/2017 02:09  Countdown in planned hold

T-minus 4 minutes and holding. The countdown has entered the planned 30-minute hold leading toward the 7:44 p.m. EDT (2344 GMT) liftoff of the Delta 4 rocket.

This pause is designed to give the launch team the opportunity to catch up on any work running behind schedule and verify all is in readiness for the final moments of the count. Also, a series of polls will be conducted during the hold to give approval to proceed with the launch.

Spaceflight101 LIVE‏ @S101_Live 2 мин. назад
 
T-4 Minutes & HOLDING! This is the final built-in hold in today's Delta IV countdown. Planned duration: 30 minutes. http://bit.ly/20U3KBx

[tnt22]

AmericaSpace‏ @AmericaSpace 3 мин назад

Once assembled the #DeltaIV moves to the pad. At the Cape, it's LC-37. #WGS9
 

[tnt22]

Брифинг по погоде:

03/19/2017 02:16  Weather is GO

Weather is observed and forecast GO for launch of the Delta 4 rocket from Cape Canaveral at 7:44 p.m. EDT (2344 GMT). In the final pre-launch briefing, the weather officer reported there are no concerns tonight and the skies remain clear.

[tnt22]

03/19/2017 02:17
The WGS 9 spacecraft is switching to internal battery power for launch.

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Tory Bruno‏Подлинная учетная запись @torybruno 2 мин. назад
 
Winds have picked up a bit, but still well within allowable. #WGS9

[tnt22]

Трансляция началась

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Chris B - NSF‏ @NASASpaceflight 1 мин. назад
 
Looks like a lovely evening at the Cape: T-4 mins - in the BIH: https://forum.nasaspaceflight.com/index.php?topic=42009.0 ...
 

[tnt22]

03/19/2017 02:26  L-17 minutes

Launch minus 20 minutes! United Launch Alliance's Delta 4 has been a workhorse for U.S. military and national security spacecraft since entering service in 2002.

Спойлер

The vehicle stands 217 feet tall, weighs about 900,000 pounds fully fueled and will unleash 1.8 million pounds of thrust at launch.

The rocket comes off the pad powered by an Aerojet Rocketdyne RS-68A engine on the Common Booster Core first stage and four Orbital ATK GEM-60 solid rocket boosters.

The throttleable RS-68A engine burns liquid hydrogen and liquid oxygen to produce 702,000 pounds of thrust. The stage measures 155 feet in length with interstage permanently attached, 16.7 feet in diameter and is covered in orange insulating foam.

The Graphite Epoxy Motor (GEM) series originated with the GEM-40 motor that was developed for the Delta 2 rocket a quarter-century ago. Cases are filament wound by computer-controlled winding machines using high-strength graphite fiber and durable epoxy resin. The "60" indicates the diameter in inches. Each GEM-60 produces a maximum of 280,000 pounds of thrust.

The cryogenic upper stage also burns liquid hydrogen and liquid oxygen to power its single Aerojet Rocketdyne RL10B-2 engine for 24,750 pounds of thrust. It features a cone-shaped carbon-carbon extendible nozzle that is 7 feet in diameter.

[свернуть]

[tnt22]

Chris B - NSF‏ @NASASpaceflight 5 мин. назад
 
And there's a Twitter quiz - WITH PRIZES - later in the broadcast.
 

[tnt22]

Chris B - NSF‏ @NASASpaceflight 3 мин. назад
 
Fans of Pad GSE will appreciate the: Huge umbilical arm, large umbilical cradle, a long duct....to keep the payload happy (environmentally).
 

[tnt22]

03/19/2017 02:34  L-10 minutes
Now 10 minutes to the target launch time! The launch team will be polled in the next few minutes to confirm all systems are "go" to press onward for the 7:44 p.m. liftoff.

[tnt22]

Spaceflight101 LIVE‏ @S101_Live 1 мин. назад

GO/No GO Polling of the ULA Launch Team, Spacecraft Management and Eastern Range is coming up in two minutes. #WGS9

[tnt22]

03/19/2017 02:37  GO FOR LAUNCH
The final readiness polls of the launch team and mission managers have been completed. No technical problems are being worked and all rocket, spacecraft and ground systems are "go" for liftoff.

[tnt22]

03/19/2017 02:38
A red alarm has sounded. Hold will be extended.

[tnt22]

03/19/2017 02:40
Liftoff will be delayed at least a few minutes while the team checks out an alarm that sounded just after the polling was completed.

ULA‏Подлинная учетная запись @ulalaunch 1 мин. назад

Hold Hold Hold. Will not release the terminal count at T-4 mins. #DeltaIV #WGS9