Final answer:
In aviation regulations, a turboprop aircraft operated in commuter operations may not be dispatched unless the Landing Distance Required at the alternate and destination airports is at most 80% of the Landing Distance Available.
Step-by-step explanation:
The question pertains to the regulations governing the dispatch of turboprop aircraft in commuter operations, specifically regarding the required landing distance in relation to the available landing distance at both the destination and alternate airports. In aviation, the Federal Aviation Regulations (FARs) stipulate dispatch regulations, including those related to landing distance assessments used by dispatchers and pilots for planning flights. It is required that the Landing Distance Required (LDR) at both the destination and alternate airports does not exceed 80% of the Landing Distance Available (LDA), leaving a safety margin that can account for variations in aircraft performance, unexpected weather conditions, or operational issues.
This rule is designed to ensure an adequate safety margin for aircraft operations, and compliance with it is crucial for the safe conduct of flights in the commuter aviation sector.