upper layer

land-based upper layer (LBUL)

Sea-Based Upper Layer (SBUL)

upper-air layer

upper air fallout

upper deck

upper sideband (USB)

upper glacis plate

adjustable upper sling swivel

upper ball race

upper center crankshaft bearing

upper edge of front sight

upper front crankshaft bearing

upper front plate

upper hemisphere

upper insulator gasket

upper motor lubricant

upper proximity dot (of a gyro gunsight)

upper rear crankshaft bearing

upper sling swivel

upper tank

upper time ring

upper water tank

upper bearing

upper torque link

upper explosive limit

wing upper surface

through shaft (of upper coaxial rotor)

upper air

upper air observation

upper air route

upper and lower coaxial rotors

upper atmosphere