Weathering a launch

  • Published
  • By 2nd Lt. Danielle Drazin
  • 30th Space Wing Public Affairs
"Our mission is really unique," said Captain Rebecca Weis, 30th Operational Support Squadron, weather flight commander. "With such a large base and the fog... it's beautiful here but difficult to forecast."

Every Air Force base has weather Airmen, but the support they provide varies based on the size and mission of the base.

According to weather flight personnel, weather support at Vandenberg is focused on launch preparation given that there are no fixed wing aircraft. Weather at all bases is monitored 24/7 to issue watch, warning and advisories for the base to protect personnel and property.
"It's a lot of support," said Capt Weis. "If there's an active runway or airfield, you have to have weather there. We work with the 25th Operations Squadron at Davis-Monthan Air Force Base, AZ, on the 'weather concept' - there are hubs around the world and we're their eyes forward at Vandenberg."

Currently, a program is being created by the 30th Space Communications Squadron for the 30th OSS to see the data collected by over 180 sensors at Vandenberg that deliver information on wind, temperatures and humidity. Weis noted that when this happens, weather at Vandenberg will only need to be manned when the airfield is open and prior to launch but at the moment manning requires someone present every day, with an Airman or civilian on telephone standby in the evening and on weekends.

Leading up to the launch

Seventy-two hours prior to a launch, the weather team begins to monitor the weather around the clock for possible violations of the Launch Commit Criteria. The LCC has a set of 10 requirements that must be met for a launch to be "green," Weiss explained. The criteria protect vehicles from trigger lightning - a phenomenon where a rocket creates its own lightning based on atmospheric changes and can lead to an explosion.

Customers can also add additional violations ranging from temperature and visibility to wind, which has the ability to change the trajectory and cause the equipment to go off course.

"Cancellation for weather is actually pretty rare. Since I've been here, we've never cancelled or held a launch based on the weather at the launch sites," Weis said.
Cancellation can be very costly - the 45th Weather Squadron, Patrick AFB, FL, reports that the cost of a "scrubbed" launch can cost from $150,000 to $1,000,000 depending on the launch vehicle.

Launch Day
On launch day, the team works separately to offer whole weather support. The Launch Weather Officer, Deputy LWO, and Launch Weather Commander work to ensure that none of the 10 LCCs are being violated. The LWO constantly monitors data to determine if it would be necessary to issue a hold or cancellation if necessary.

"The rocket could blow up if it violates any of the LCCs we monitor for," said Weis. "It can become its own lighting rod. It has happened before."

The LCCs are monitored using weather balloons. On launch days, between three and 15 weather balloons are released. According to the National Oceanic and Atmospheric Administration, sensors in weather balloons measure air pressure, temperature, relative humidity, and wind direction and speed.

"On launch day, if we're concerned about the weather we also have a weather aircraft that will tell us cloud bases and heights so we can determine if the weather will violate our criteria," said Weis.

Although she rarely gets to view the launches, Weis said she gets a thrill from knowing she's a part of the launches. "The best part of my job is being a part of the launches and seeing what they've been able to put in to space - it's a really cool mission," she said.