Falcon 1 Flight 3 Launch Thread

[spcefrk]

I didn't realize fuel could get too cold; how so?

I don't know specifics about the Falcon 1, but with liquid propulsion, you often have to preheat the cryogenic fuel before it goes into the combustion chamber. This is usually achieved by circulating it around the nozzle (which provides the dual effect of cooling the nozzle). If you allow the fuel to get too cold, the exhaust gas isn't as hot as it could be and you see a drop in the thrust.

In fact, unless I'm mistaken, you want the exhaust gases as hot as possible. The limiting factor is usually the thermal limits of the nozzle material.


-----Double Post Auto-Merged 2/8/2008 at 09 : 04 : 12-----

Webcast hasn't 'resumed' yet.
And interestingly the hold is now for 55 minutes, not 16. I guess they're taking a big step back.

How big is their launch window? (Or do they not have a target?)

 

[synonys]

It's like the longer you watch the longer the schedule slips, it's a vicious cycle.

 

[Quick_Nick]

How big is their launch window? (Or do they not have a target?)

2 more hours in the window if I'm not mistaken.
From first post:
"The launch window will open at 4:00 p.m. (PDT) / 7:00 p.m. (EDT) and remain open for five hours."

 

[astrosammy]

Hurry up! I don't want to wait two months for it like on STS-122.

 

[Quick_Nick]

Countdown resumes at T-55min!
Still no audio in the webcast it seems...

Now T-50 minutes and still counting.

 

[Andy44]

Something tells me that's not the best place to put a flag...

 

[Quick_Nick]

Posted August 2, 2008 - 19:03 PDT
We are still holding at T-16 minutes. We are very confident that we will launch before today's window closes at 9:00pm PDT / 12:00am EDT / 04:00 UTC. Please check back in 30 minutes for further updates.

They SOUND confident

Something tells me that's not the best place to put a flag...

Good point! Industrial strength flags, maybe?

 

[Andy44]

It's going to look like Tranquility Base's flag! Although I can't remember if the tower swings down and away before liftoff?

 

[DaveS]

We have re-entered procedures at T-55 minutes and are reloading fuel. Liftoff is now expected at 08:00pm PDT / 11:00pm EDT / 03:00 UTC.

 

[astrosammy]

OOOOK

To prevent fuel from getting too cold, we are detanking.

They detank because of the fuel getting to cold because the refueling needs longer because of the warm weather :huh::huh::huh::huh:.

 

[DaveS]

OOOOK


They detank because of the fuel getting to cold because the refueling needs longer because of the warm weather :huh::huh::huh::huh:.

No. You're getting the Helium(a pressurizing agent) mixed up with the RP-1(the fuel, a highly refined version of kerosene).

The RP-1 shares bulkhead with the LOX tank. The LOX chills the RP-1 down and the engines do not like cold RP-1. So to prevent the the RP-1 from getting too cold, they offloaded some of it so that they could reload warm RP-1 heating the RP-1 already in the vehicle.

 

[DaveS]

LOX topping in effect again.

 

[Quick_Nick]

Yay! We're getting somewhere!... and there's sound! :lol:
EDIT: 1st stage fuel load complete

 

[DaveS]

First stage fuel loading complete.

 

[Quick_Nick]

30 minutes to launch!

 

[DaveS]

Ascension Island is GO. Weather is GO.

 

[thomasantony]

Weather looking good at T-27:20

 

[Andy44]

Orbiterhead launch thread GO!

 

[Quick_Nick]

It's Elon! XD

 

[thomasantony]

Webcast resumes. Now showing a private tour of the SpaceX facility in California.