Peak-season wet lease of a third-country-registered aircraft
You are the nominated postholder for flight operations at an EU air carrier holding an AOC issued by a Member State. To cover a summer schedule you sign a four-month wet lease - aircraft, crew and maintenance - for a Boeing 737-800 registered in a State outside the EU and operated by a carrier licensed there. The aircraft holds a Certificate of Airworthiness and an airworthiness review certificate issued by that State, and the flight crew hold licences issued by the same State. Marketing wants to sell seats on your flight numbers between three EU cities, starting in twelve days. The aircraft carries a deferred item, a cargo compartment fire bottle, approved under the lessor's MEL but not listed in yours. Your operations manual says only that leases require approval where applicable, and the lessor's maintenance is done to its own programme. The authority has not yet been contacted. Marketing asks whether it can start selling the flights.
1. Before a single seat is sold, what approvals and legal conditions must be satisfied, and which Chicago Convention Articles underpin the acceptability of the foreign certificate and licences?
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Three separate questions are being merged here, and each has a different answer.
Registration (Chicago Art. 13). Registration is a matter for the State of registry; nothing in the Convention forces an EU operator to use an EU-registered aircraft. The aircraft can stay on the third-country register. But registration determines which State certifies airworthiness and issues the crew licences, which is exactly why the structure needs regulatory approval rather than just a contract.
Certificate of airworthiness (Art. 33). The State of registry certifies that the aircraft is airworthy and that its requirements for issue and maintenance equal or exceed ICAO minimum standards. Other States must recognise that certificate, so the foreign C of A is not invalid in itself. Recognition is not oversight: the certificate is only as good as the third-country system behind it, and the EU carrier remains responsible for the safety of the flights.
Crew licences (Art. 30). Licences issued by the State of registry are in principle accepted by other States for flights over their territory; a State may refuse to recognise, for flight over its own territory, licences issued by another State to its own nationals. A third-country crew flying a third-country-registered aircraft therefore raises no automatic licensing bar.
The EU overlay decides it. Under Reg. (EC) 1008/2008 Art. 13, an EU carrier may wet-lease an aircraft registered in a third country only with prior approval of its competent authority, only for exceptional needs and a short period, and with notification to the Commission and EASA. The operator must also meet the leasing-agreement requirements of ORO.AOC.110, show it can exercise oversight of the aircraft and crew for the lease period, and have the aircraft in its insurance and operational documentation. Four months of planned peak-season cover is exactly what the authority will test against 'exceptional needs' and 'short period'. Marketing cannot sell before that approval exists.
2. The lessor's MEL shows the cargo fire-bottle deferral as acceptable. Can you dispatch under your AOC with that deferral, and what must happen to the maintenance arrangements?
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No, not on the strength of the lessor's approval. An MEL is an operator-specific document approved by that operator's competent authority. It derives from the MMEL, but the relief, the operational and maintenance procedures and the rectification interval are approved for that operator's fleet, configuration and route structure. The lessor's approval says nothing about your aircraft, your authority or your procedures, and your authority has not seen it.
The deferral must be re-assessed against your MEL. Depending on the entry, an inoperative cargo fire bottle may attract conditions such as a prohibition on carrying cargo in the affected compartment, restrictions on extended overwater or ETOPS flight, and a defined repair interval. If your MEL gives no relief for that item, or the conditions cannot be met on the planned routes, the aircraft may not be dispatched with the defect and must be repaired before the lease begins. If relief exists, it must be raised under your own deferred-defect procedure, with your continuing airworthiness organisation's concurrence and your authority's approved process.
Maintenance is the larger issue. For the lease the aircraft must be maintained to a programme acceptable to your competent authority, and continuing airworthiness management must be contracted in writing to an organisation acceptable to that authority, with clear responsibility for airworthiness review, airworthiness directive compliance and defect control. The fact that the lessor's own programme and organisation are acceptable to its own State is not sufficient: the authority approving the wet lease has to be satisfied that effective oversight exists for the whole period. That is precisely why Art. 13 approvals are time-limited, and why the operator should expect conditions on defect reporting, record access and return of the aircraft.
3. Five weeks into the lease, an engine-driven generator fails. The part is not in your stores; the lessor's maintenance organisation can replace it in 48 hours. Commercial wants the aircraft to fly the weekend programme with the generator deferred. What is your decision and reasoning?
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Start from the MEL. Many operators' MELs give no relief for a generator on a twin-jet, and any relief that does exist usually carries restrictions on route structure, alternates or overwater operation. If your MEL permits the deferral and the conditions can be met, the aircraft remains legal; if it does not, no amount of commercial pressure changes the answer and the aircraft does not fly.
Even where relief exists, three further factors decide it. First, the approval: the wet-lease approval expires in a week, and a defect that runs past it must be handled by whoever holds the aircraft afterwards; the authority should be told now, not after the weekend. Second, the oversight chain: a 48-hour repair by the lessor's organisation is acceptable only if that organisation is working to the programme and arrangements agreed for this lease, with your continuing airworthiness organisation controlling the work order and the certificate of release to service. Third, the operational consequence: a deferred generator may restrict the very route structure the commercial team is trying to protect.
The decision is to have the generator replaced and to plan the weekend on the basis that the aircraft is unavailable until released, or to source a replacement aircraft. If a legal deferral were available it would still need a written assessment, a briefing to the commander and the authority's awareness. The commander's decision on the day would be to refuse the aircraft if the defect affects the safety of the flight; the operator's duty is not to turn that into a commercial choice.