Definition
The metal bulkhead at the back of the propeller spinner that mounts against the propeller hub and faces aft toward the engine. It carries the spinner shell, helps direct cooling air into the engine compartment, and is a standard inspection item during preflight for cracks or loose fasteners.
Plain English
The flat metal disc behind the cone-shaped cover on the propeller. It holds the spinner cover in place and points back toward the engine. Pilots check it before flight for cracks or loose screws.
Context Anchor
Seen during preflight inspection of the propeller and spinner area at the front of the airplane.
Derivation
Rear-facing simply means the side that points backward (toward the engine). Spinner is the cone-shaped cover over the propeller hub, so named because it spins with the prop. Plate refers to the flat metal disc that backs the spinner.
Why Pilots Care
Loose or damaged plates can cause spinner detachment, vibration, or imbalance that affects propeller operation and safety.
Intuition Check
Do not read “rear-facing” as “installed backward.” Here it means the spinner plate at the back side of the spinner, facing toward the airplane.
Example Sentence 1
During preflight, the pilot checked the rear-facing spinner plate for cracks where it meets the propeller hub.
Example Sentence 2
Mechanics torqued the bolts on the rear-facing spinner plate after replacing the propeller.