Final answer:
Modern aircraft propellers have safeguards like counterweights or nitrogen-charged accumulators that automatically adjust the pitch to a coarse or feather position in case of lost oil pressure, thus minimizing drag and preventing overspeed.
Step-by-step explanation:
Safeguards for Lost Oil Pressure in Propellers
When dealing with aircraft propellers, oil pressure is crucial for controlling the pitch and, hence, the performance of the propeller. If oil pressure is lost, most modern propeller systems have a built-in safeguard to prevent loss of propeller functionality. This usually comes in the form of a counterweight system or a nitrogen-charged accumulator that drives the propeller blades toward a coarse pitch or 'feather' position, allowing the propeller to reduce drag and prevent overspeed conditions. In some cases, a pitch lock mechanism can also be engaged, which restricts the movement of the blades and ensures that they stay at a safe operational pitch until the issue is resolved.