Countdown to Endeavour: Lightning Protection Is a Must

By Carla Voorhees

Kathy Winters is an Air Force Civilian Meteorologist at the 45th Weather Squadron at Cape Canaveral Air Force Station. She is the Space Shuttle Launch Weather Officer providing weather support to the Space Shuttle Program at Kennedy Space Center as the Launch Team prepares for the 29 April 2011 launch of Endeavour. You can find out more about the 45th Space Wing at their Facebook page.

As launch day approaches, we are expecting thunderstorms to impact the Florida East Coast, some which could produce severe weather. When meteorologists use the word “severe weather,” we aren’t talking about the everyday, afternoon thunderstorms. Severe weather indicates thunderstorms could produce winds 50 knots or greater, hail, and/or tornadic activity.  If severe weather occurs, the Shuttle team inspects the vehicle to ensure weather has not caused any damage. Also, if we have close lightning strikes, we provide detailed lightning data to ensure the team knows if the strike potentially caused damage to the shuttle or any launch pad ground systems.

Lightning protection for launch complexes is a must, and the Kennedy Space Center and Cape Canaveral Air Force Station launch pads have a significant amount of lightning protection to protect vehicles and launch pad structures from damage due to lightning strikes. For the Shuttle launch pad, a 1-inch thick grounded wire stretches 1000 feet each direction from the 80-foot fiberglass mast at the top of the structure. A 4-foot lightning rod extends from the mast. All structures on the pad are grounded, including the Mobile Launch Platform. The hydrogen, oxygen, and water storage tanks provide their own ground, and a gridwire system protects hypergolic fuel storage areas. Overall, the area is well protected to minimize damage from lightning.

To learn more about lightning, check out the National Severe Storms Laboratory.

Luckily, by launch day, the weather should be off to our east, and our main concerns are a low-cloud ceiling and a crosswind at the Shuttle Landing Facility for abort landing weather. Wish us luck!