Which requirement does not apply to on-demand operations under Part 135?

In the context of on-demand operations under Part 135, one of the key requirements is the regulation concerning the rest and duty times for flight crews. The regulations stipulate specific minimums to ensure that pilots are adequately rested before commencing flying duties.

The requirement for a 10-hour rest period before the start of duty is significant because it promotes safety by ensuring that pilots have adequate time to rest and recover from fatigue. The 8-hour minimum duty period ensures that a pilot’s time spent on duty does not exceed certain limits that could lead to fatigue during flight operations.

The mention of a 9-hour rest period is not applicable to on-demand operations, as this duration does not meet the regulatory standards set forth for Part 135. The regulations emphasize either a longer rest period or other rest conditions that replace the standard duty expectations with specific requirements that prioritize pilot fatigue management.

Therefore, 9-hour rest stipulation does not align with the established framework for Part 135 operations, making it the requirement that does not apply.