Definition
A propeller blade forging or casting that has been shaped to its rough outline but has not yet been machined, finished, or twisted to its final airfoil profile and pitch. It is the raw, unfinished blade from which a finished propeller blade will be manufactured.
Plain English
A propeller blade in its rough, unfinished form before it has been shaped into its final flying shape.
Context Anchor
Seen in propeller, rotor, and aircraft maintenance or manufacturing discussions.
Derivation
Blank' here means an unfinished piece of material that has been roughly shaped but not yet brought to its final form — the same sense used in 'key blank' before a key is cut. Pairing it with 'blade' simply tells you which kind of blank.
Why Pilots Care
A blank blade is not airworthy equipment. It should not be treated as a serviceable blade or installed for flight until all required finishing and approval steps are complete.
Intuition Check
“Blank” does not mean empty, plain, or unmarked here. It means unfinished: shaped enough to recognize, but not complete enough to use.
Example Sentence 1
The propeller shop kept a supply of blank blades on hand so they could machine replacements when a damaged blade was sent in.
Example Sentence 2
Inspectors checked the blank blade for forging defects before releasing it to the contouring station.