In March of 2012, NASA successfully launched five rockets from its Wallops Flight Facility in Virginia. The launch was part of NASA's Anomalous Transport Rocket Experiment, or ATREX, which will help scientists better understand the jet stream. Jack Vieira, range project manager for the ATREX mission, helped to launch five suborbital rockets more than 60 miles above Earth.
NASA Tech Briefs: Jack, let's set the stage here. Can you take us through what happened on Tuesday, the day that the rockets launched? (March 24th)
Jack Vieira: We had a very dynamic operation that night. We knew that we were going to have some difficulties with winds that evening, so we set up a little bit later than we would typically. We had a launch window from midnight until 5 am, and we knew the winds were going to be strong, but hopefully dissipating somewhat as the evening progressed. In anticipation of that, we opened a window at 0200 local, rather than midnight. We still had very strong winds at that time. We were really concerned if we would be able to get the rockets off that evening. Luckily the wind gods were smiling down on us, and at the very end of the window, we did a Hail Mary pass, and we were able to get the rockets off.
NTB: So the wind didn’t affect the rockets?
Vieira: We had two rockets with attitude control systems, but most of the rockets are point-and-shoot type rockets. We have to do wind wading, where we launch a bunch of balloons: a four-and-a-half hour balloon, that goes up to 100,000-plus feet, and then a mid-altitude balloon up to 50,000 feet.
At one hour and 15 minutes, we start launching balloons every 15 minutes. We’re capturing data as it goes up. We have a column of air from the surface all the way up to 100,000 feet, with the definitions, with the velocities, and directions of the winds. With that, we calculate what the azimuth and elevation settings should be, so that we can anticipate how the winds are going to affect the rockets.
For example, if we had strong winds and we were going to launch 100 degrees azimuth at an 87-degree elevation, our wind corrections would change that. We could change that as much as 30 degrees on azimuth to make the corrections, so that it actually flies to 100 degrees.
NTB: What are the goals of the ATREX mission? What are you trying to discover?
Vieira: The PI, Dr. Miguel Larsen from Clemson University, had made a proposal to NASA headquarters, and got it approved. They noticed that way back in the 1960s, and then more recently with the shuttle missions, that in the higher altitudes, the 60-65 mile altitudes, there were extremely high winds (between 200- and 300-mph winds), and they just didn’t understand the dynamics there. Why was that happening?
Then also, there was the fact that those altitudes, some of the communications with satellites and such, were being distorted some, so they were trying to get a better understanding of what happens at those altitudes that create those kinds of winds.