MESSENGER Webcast: MESSENGER Mission Overview
Launch Processing Update and Weather Forecast

Nail: NASA Launch Manager Chuck Dovale joins us now live. Welcome, Chuck.

Chuck Dovale: Thanks, Tiffany. It's great to be here.

Nail: I'm sure our viewers are interested in knowing about what goes on before a launch occurs. As Launch Manager, could you tell us about the launch process and how the team at Cape Canaveral Air Force Station prepares the vehicle for liftoff?

Dovale: Sure. As you can imagine, it takes hundreds of people from NASA and Boeing and several contracting organizations to take on a task like this, and a lot of them were part of mission to Mars, mission to Saturn and now, mission to Mercury. And I have some processing videotape I'd like to show you of a booster going up on the pad.

This is the heavy configuration of the Delta II booster; heavy in that it's had a beefed up center body section to allow for the larger version solid rocket motors, which were originally designed for the Delta III vehicle. And this is the booster going up in the tower, and rolling to the launch mount, these are the solid rocket motors going on, and it looks like that guy is lifting it himself but believe me, it's being lifted by a crane.

There are nine solid rocket motors around the aft end of the booster. This is a shot of the second stage, it's made by Aerojet, provides about 2,500 pounds of thrust. There's a shot of it going into the Mobile Service Tower and it would be mounted on the inner stage of the booster. Here's a shot of the third stage and the MESSENGER spacecraft in the canister being hoisted up onto the tower. This is a three-stage mission very similar to the MER-B mission from last summer.

There's just a view of a lot of the Boeing engineers and technicians that it takes to mate the spacecraft to the launch vehicle. They're lowering it down onto the second stage, and again that's a combination of the third stage and the spacecraft together. There's a shot of the top of the spacecraft and an operator working the crane as the protective fairing, two halves of the fairing come around and that's a great shot of the spacecraft there and its heat shield. There's the fairing coming around and being bolted together.

Okay. So that's what it takes, I can tell you it's quite an ordeal, and the team is just as excited as they can be. You know, exploration is great and especially interplanetary exploration. I wanted to also talk about the countdown that is going to take place Sunday night, it's approximately 12 hours long, and we'll have a weather brief about 3 p.m. Saturday afternoon and they will roll the tower about 4 p.m., the mobile service tower will come back exposing the rocket. The spacecraft will be powered up shortly after that, about 4:30 p.m. The team will start to move deck plates and get into a launch configuration, and then the terminal countdown will start at 11:16 p.m. local time Sunday evening.

At that point, we'll have two built in holds in the last three hours to use for catch-up in case we run behind on some tasks. We'll load fuel and liquid oxygen into the first stage and make sure that's all set to go. We'll also do one final engine check. We gimbal or move the engines in a pre-programmed pattern and make sure they are ready for flight and that happens at about T-30 minutes.

The spacecraft will go on internal power at six minutes out, and we'll give the final go for launch and we hope to lift off at 2:16:11 local time Monday morning.

Nail: Great. Thanks for being with us today, Chuck.

Dovale: Great, thank you.

Nail: We all look forward to seeing you on launch day.

Dovale: I appreciate it.

Tiffany: Our final guest today is the weather officer for the MESSENGER launch, Joel Tumbiolo. Hello Joel, thank you for joining us.

Joel Tumbiolo: Glad to be here.

Nail: The weather plays a crucial part in a launch. Could you tell us what you look for as we prepare for liftoff and what does the weather look like for MESSENGER's launch window?

Tumbiolo: Well, first off, before I get into the actual weather on launch day, I'd like to touch on the first part of my job. Chuck just pointed out all the ground processing operations that have to go into getting a vehicle ready for launch -- putting up the booster, putting up the satellite, doing all the checks that need to go on -- all those, although the video showed clear blue skies on those days, trust me, it's not always that way.

So, my job, actually the hardest part of my job, is just getting the vehicle ready to get to launch day. All those processes have very stringent weather constraints -- wind, lightning, and especially around here during the summertime, thunderstorms -- so, we've been dealing with that a lot. And once we get all that and have the rockets ready to go and everything is ready to go and we get to the launch day, my first job, again as Chuck just indicated, I'll be providing a briefing around 3 o'clock on Sunday afternoon and that'll be for this mobile service rollback.

As it stands right now, it looks like that's going to be the worst weather throughout the entire countdown. We do expect afternoon thunderstorms on Sunday afternoon and again, we're going to be looking for the winds and the lightning within five nautical miles of the launch pad. And if we have winds greater than 40 knots or we have lightning within five nautical miles, we will not be able to roll the tower back, so we will have to wait until those lightning storms are beyond us.

So once we get beyond that point and we actually get into the launch countdown, my next chore would be to provide a briefing for them to start loading fuel onto the rocket. Assuming all goes well, my next job is to follow a set of rules that NASA, the Air Force and safety have come up with to ensure that there’s going to be a safe launch -- there’s about 10 or 11 rules, I won’t get into the nuts and bolts of them all, but there are 10 rules that I have to monitor -- all the rules have to do with lightning and wind -- and if all those rules are satisfied, then I will give the "Weather is go for liftoff."

Hopefully all those will come together. Again, I think our worst conditions will be Sunday afternoon as we get to that tower rollback timeframe. There are a couple of systems out in the ocean that we're watching; I don't think either one of them is going to be an issue for us. There's one out to the east and another out to the Gulf of Mexico that we’re watching. But we are getting into our time of hurricanes here, but again I don't believe those systems will play a role. It's going to be mainly local weather Sunday afternoon and evening playing a role and hopefully, we'll get through that and launch safely. Thank you.

Nail: Thank you, Joel, for that weather update. We'll all keep our fingers crossed.

Tumbiolo: Thank you.