Cathay Pacific Airways Ltd v Lufthansa Technik AG

A clearly drafted contractual option permitting partial withdrawal from a service programme is ordinarily effective according to its terms. It is not confined by commercial purpose, good faith, or a Braganza-type limitation unless the contract and context justify such implication. A detailed maintenance agreement between sophisticated commercial parties was not a relational contract. A good faith term was neither obvious nor necessary for business efficacy. Contractual reconciliation mechanisms operated independently, and the court would not correct an unwise financial bargain through interpretation.

The claimant airline and the defendant aircraft-engine maintenance provider entered into a ten-year maintenance agreement. The agreement gave the claimant an option to remove engines from the Flight Hour Services programme and provided for a Schedule 13 financial reconciliation. Shortly before expiry, the claimant removed all engines, while retaining other contractual services, and claimed substantial reconciliation sums.

The defendant contended that the option was limited to operational removals, subject to restrictions against arbitrary or unreasonable exercise, and qualified by a general obligation of good faith. It also disputed the calculation of a second reconciliation charge and the claimant’s set-off entitlement.

1. Construction of the option. Clause 21.2 conferred a unilateral option to remove any number of engines from the Flight Hour Services programme before expiry. Its language did not restrict exercise to operational reasons or removal from the fleet. The option was partial: the engines remained subject to the agreement and other services could continue. The Schedule 13 reconciliation was the agreed financial consequence of exercise.
2. The option was not inconsistent with the termination, exclusivity, or Schedule 4 provisions. The parties had deliberately provided separate reconciliation mechanisms. The court would not use commercial consequences to rewrite clear language or cure a failure to consider the financial effect of the agreed formula.
3. Implied restrictions. No term limiting exercise to operational purposes satisfied the requirements of obviousness or business efficacy. Nor was a Braganza/Socimer term justified. The option was a contractual right for the claimant’s benefit, not a decision-making function involving an assessment of facts or a choice between options while balancing both parties’ interests.
4. The agreement was not a relational contract. Although long-term, exclusive, and involving substantial communication and co-operation, it was a detailed and substantially impersonal contract for maintenance services. The parties had defined their obligations, risks, adjustments, and remuneration precisely. A mutual good faith term was neither obvious nor necessary for business efficacy.
5. Even if such restrictions had existed, the claimant acted rationally and in good faith. It gave the defendant a reasonable opportunity to make commercial proposals concerning APU engines and remained willing to consider them. The claimant therefore validly exercised clause 21.2.
6. The Schedule 4 and Schedule 13 calculations were independent. Flight hours were neutral inputs and were not double-counted. The correct figures were 386,779 total engine flight hours, actual average utilisation of 3,150 hours, and an actual severity factor of 0.9366. The second reconciliation charge was US$2,654,968.83, and the first reconciliation did not require recalculation.
7. The claim succeeded in US$9,694,540.10 plus interest. The counterclaim was dismissed.