X-37B Space Plane: US Air Force's 4th Mystery Mission in Photos

Mystery Space Plane to Launch May 20

ULA

The Air Force's AFSPC-5 payload inside a 5-meter diameter payload fairing undergoes mating to an Atlas V booster inside the Vertical Integration Facility at Cape Canaveral Air Force Station's Space in Florida. Launch is set for May 20, 2015.

AFSPC-5 Payload Mating Distant View

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The Air Force's AFSPC-5 payload inside a 5-meter diameter payload fairing undergoes mating to an Atlas V booster inside the Vertical Integration Facility at Cape Canaveral Air Force Station's Space in Florida. Launch is set for May 20, 2015.

AFSPC-5 Payload Encapsulation

ULA

The Air Force's AFSPC-5 payload, encapsulated inside a 5-meter diameter payload fairing, is mated to an Atlas V booster inside the Vertical Integration Facility or VIF at Cape Canaveral Air Force Station's Space Launch Complex-41. Launch is set for May 20, 2015.

AFSPC-5 Payload Encapsulation High Angle

ULA

The Air Force's AFSPC-5 payload inside a 5-meter diameter payload fairing undergoes mating to an Atlas V booster inside the Vertical Integration Facility at Cape Canaveral Air Force Station's Space in Florida. Launch is set for May 20, 2015.

AFSPC-5 Payload Encapsulation Looking Out

ULA

The Air Force's AFSPC-5 payload inside a 5-meter diameter payload fairing undergoes mating to an Atlas V booster inside the Vertical Integration Facility at Cape Canaveral Air Force Station's Space in Florida. Launch is set for May 20, 2015.

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