Photos: Mobile gantry retracted from ULA’s Delta 4-Heavy for Aug. 27 launch attempt

Towering more than 30 stories tall, the mobile gantry structure at the Delta 4-Heavy rocket’s launch pad at Cape Canaveral was wheeled into position for liftoff of the triple-core launcher Thursday with a classified payload for the National Reconnaissance Office.

The mobile gantry — which weighs around 9 million pounds — is moving on rail tracks to a park position around 300 feet northeast of the launch mount at Complex 37B.

The structure provided weather protection for the Delta 4-Heavy, and access to the launch vehicle for engineers and technicians, since the rocket’s rollout and erection at the launch pad last November. The tower stands around 330 feet tall, and measures 90 feet wide and 40 feet deep. It was built before the first Delta 4 launch in 2002.

The rollback of the Mobile Service Tower on Wednesday evening revealed the 235-foot-tall Delta 4-Heavy rocket for liftoff early Thursday. The triple-core rocket, built by United Launch Alliance, will carry a classified satellite into orbit for the National Reconnaissance Office, the U.S. government’s spy satellite agency.

The photos below show the retraction of the mobile gantry Wednesday. See our Mission Status Center for live countdown and mission coverage.

Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance
Credit: United Launch Alliance

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