* Astronomy

Blobrana · L

RE: NAVSTAR launch

Blobrana · L

The planned hold in the countdown has been released.
Clocks will now tick down to T-minus 4 minutes where the final hold is scheduled.

Blobrana · L

T minus 44 minutes

The countdown has entered the 20-minute built-in hold.
Two holds are planned at T minus 20 minutes and T minus 4 minutes.

At T minus 20, the first stage kerosene fuel tank will be pressurised for launch.

-- Edited by Blobrana at 03:51, 2005-09-26

Blobrana · L

T minus 1 hour
Engine steering checks starting

Blobrana · L

T minus 1 hours 10 minutes
Engine steering checks will soon start of the first and second stage engines.
These are gimbal tests of the nozzles on the first stage main engine and twin vernier engines and second stage engine to ensure the rocket will be able to steer itself during launch.

This operation should last 10 minutes.

Blobrana · L

T minus 1 hours 20 minutes
All continues to go well today.

Loading of the Delta 2 rocket's first stage liquid oxygen tank was completed. The operation takes 25 minutes. The tank will be replenished through the countdown to replace the super-cold liquid oxygen that naturally boils away.
The rocket is now fully fuelled for launch. The vehicle's first stage was successfully loaded with RP-1 kerosene fuel along with the liquid oxygen today. The second stage was filled with its storable nitrogen tetroxide and Aerozine 50 fuels. The three strap-on booster rockets are solid-propellant.
Next up in the countdown will be engine steering checks starting about 10 minutes from now.

Blobrana · L

T minus 1 hours 30 minutes
The countdown is entering the final 90 minutes to lift-off.
It takes about 25 minutes to fill the rocket. Once the first stage tank is 95 percent full, the "rapid load" valve will be closed and the slower "fine load" phase will continue to fill the rocket.

The outer skin of the first stage is icing over as the liquid oxygen fills the tank.

Blobrana · L

T minus 1 hours 45 minutes
The launch team has been given a "go" to start the preparations for loading the rocket's first stage liquid oxygen tank.

Super-cold liquid oxygen is starting to flow into the first stage of the Boeing Delta 2 rocket.
The liquid oxygen, chilled to Minus-298 degrees F, is being pumped from a launch pad storage tank, through plumbing and into the bottom of the rocket.
The LOX and the RP-1 kerosene fuel - loaded aboard the vehicle a few hours ago - will be consumed by the first stage main engine.

Blobrana · L

T minus 1 hours 50 minutes
Before the hazardous operation of liquid oxygen loading starts roadblocks around the pad are established and the flight hazard area are cleared of all personnel.

Blobrana · L

T minus 2 hours
The first stage fuel tank has been fully loaded. Super-cold cryogenic liquid oxygen will be loaded next.
Second stage propellant tank pressurization has been completed. The stage will then be loaded with storable hypergolic propellants.