The Ferry Flight That Ran Out of Duty Day
A charter operator flies a twin turboprop on a domestic cargo run. The crew reports for duty at 05:40 local, having had 7 hours of rest. The planned rotation is four sectors, with a scheduled finish at 17:10. On the third sector, a pressurisation fault forces a return to departure, and the aircraft is grounded. The operator wants the crew to wait 3 hours and then ferry the unpressurised aircraft to base at 9,000 ft, a 1 hour 50 minute flight. The captain's flight time so far is 6 hours 20 minutes; the company limit is 8 hours flight time in any 24 hours and a maximum duty period of 13 hours. The captain has a 09:00 sim session booked the next morning. The first officer has 4 hours 10 minutes flight time.
1. Can the crew legally and safely operate the ferry sector under the stated limits? Show the arithmetic and identify the binding constraint.
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Duty began 05:40. The 3-hour wait pushes the ferry departure to roughly 15:40 at the earliest, and the sector is 1 h 50 min, so the duty period would end around 17:30 - about 11 h 50 min after report. That is inside the 13-hour duty limit, so duty is not the binding constraint.
Flight time is. The captain already has 6 h 20 min. Adding 1 h 50 min gives 8 h 10 min, which exceeds the 8-hour flight-time limit by 10 minutes. The first officer would reach 6 h 00 min and is fine.
So the ferry cannot be flown with this captain under the company limit. Options: swap in a captain with sufficient remaining flight time, or delay the ferry until after the 24-hour window resets. The unpressurised ferry at 9,000 ft is itself permissible only with oxygen and terrain clearance considered, but that is a separate question. The 09:00 sim the next morning also requires checking the rest requirements before any late finish.
2. The operator argues the ferry is a maintenance flight and therefore outside the duty limits. How should the captain respond?
Read the worked answer
The captain should reject that reasoning. A ferry flight with a crew aboard is a flight for the purposes of flight-time and duty limits; the label 'maintenance flight' does not convert it into non-flying duty. The limits exist to protect against fatigue, and the captain's 6 h 20 min already accumulated is real flight time regardless of the purpose of the next sector.
The captain is the final authority on the safety of the flight. Even if the operator asserts an exemption, the captain should require the operator to produce the specific regulatory provision in writing, and should decline to fly if it is not clearly established. Exceeding a flight-time limit is also an enforcement matter for the pilot, not only the company.
A practical resolution: ferry the aircraft with a fresh crew, or position the aircraft the next day. The captain should record the decision and the reasons in the operational log so the judgement is documented.