NASA Home Page NASA Home PageJohn F. Kennedy Space Center - NASA Facts On Line

KSC Home Page Site Search FAQ's Site Survey Customer Forum NASA Centers Privacy Statement Headlines

Countdown! NASA Launch Vehicles and Facilities
PMS 018-B 
October 1991
Section 4

Launch Pads 39A and 39B

Previous Page

Next Section

Table  of Contents KSC Fact Sheets Next Page

The Launch Complex 39 Pads A and B are roughly octagonal in shape. Each covers about 0.25- square-mile (0.65-square-kilometer) of land, contained within a high chain link fence. Space Shuttles launch from the top of the concrete hardstand in the center of the pad. The Pad A stand is 48 feet (14.6 meters) above sea level at its top, while the upper surface at Pad B is at an elevation of 55 feet (16.8 meters).

Approximately 105 Space Transportation System (STS) 51-L accident-related pad modifications were made before the STS-26 return-to-flight mission in September 1988. Although pad equipment was not found to be a contributing factor in the accident, the modifications improved flight safety margins and corrected possible problems in emergency escape hardware and procedures.

Some of the modifications include extensive changes to the Crew Emergency Egress System. The personnel escape route from the Shuttle, beginning with the orbiter access arm, has been covered with solid panels for fire protection. A water spray system also has been incorporated. Two slidewire baskets have been added to the slidewire system for a total of seven, along with devices to decelerate the baskets and to improve exit from them. The old emergency shelter bunker near the end of the slidewires, which the crew would enter to wait out the emergency, has been replaced by a new version.

Other modifications include the addition of a solid rocket booster joint heater umbilical to keep booster field joints at or about 75 degrees Fahrenheit (24 degrees Celsius), and a system to recirculate launch pad water services to prevent them from freezing. Still other modifications are improvements to the environmental controls in the Payload Changeout Room, the addition of a cryogenic liquid-propellant filter device, and the inclusion of an automatic secondary release system for the Shuttle external tank hydrogen vent umbilical.

The top of each pad measures 390 feet by 325 feet (119 meters by 99 meters). The two major items of equipment on each pad are the Fixed Service Structure and the Rotating Service Structure.

 Top of Page

KSC Home Page Site Search FAQ's Site Survey Customer Forum NASA Centers Privacy Statement Headlines

Page Last Revised

Page & Curator Information


 Curator: Kay Grinter ( / InDyne, Inc. 
Web Development: JBOSC Web Development Team
A Service of the NASA/KSC External Relations and Business Development Directorate
JoAnn H. Morgan, Director