Airbus finance chief Harald Wilhelm will leave in 2019, the European plane maker announced on Monday, removing a leading contender to replace chief executive Tom Enders who is also set to depart next year.
"Until then, I remain committed to the performance of the company and I will work with the management to ensure a smooth transition to the next Airbus CFO," said Mr Wilhelm, who joined the company in 2000.
The successors to both Mr Enders and Mr Wilhelm face challenges including declining orders and the possible loss of a 100 plane order from Iran which is now in jeopardy due to plans by US President Donald Trump to reimpose sanctions on Tehran.
The deal, worth approximately $18 billion to $20bn at list prices, was agreed in December 2016. But only three planes have been delivered, with industry sources blaming delays on the wariness of banks to finance business with Tehran.
Iran has said it expects to hear from Airbus about the fate of the deal in the coming days.
Airbus also faces a changing product mix, with slowing A330 passenger jet sales prompting it to forecast a 17 per cent drop in 2019 deliveries of its most successful wide-body jet, under intense competition from US rival Boeing's 787 model.
Airbus shares fell 1.5 per cent to €97.98 after last week touching a record high of €100.42.
UBS analysts said Wilhelm's departure was a blow, although they kept a "buy" rating on Airbus shares, while two fund managers said the fall in Airbus' shares reflected broader concerns over its business in Iran and a rise in the euro.
"It would have been more worrying had Wilhelm stepped down immediately, but he's leaving next year, so Airbus will have plenty of time to find a replacement," said Prime Partners' fund manager Jerome Schupp, who said he prefers Boeing shares to those of Airbus.
Clairinvest fund manager Ion-Marc Valahu said Mr Wilhelm's departure was less of an issue than Airbus' potential problems over its Iran contracts, as well as a strong euro which can impact European exporters.
Airbus said that a candidate for chief executive will be submitted to shareholders at the annual meeting in spring 2019 and Mr Enders would help to secure a smooth transition.
The Airbus board is keen to assert control over the appointments process, according to industry observers, after the company changed its rules in 2013 to reduce the influence of the French and German governments, which each own 11 per cent of the company.
During the first 12 years after a pan-European merger in 2000, top jobs had been divided up between France and Germany to protect national interests. Now there are fewer restrictions.