Lufthansa shares fell as much as 4.2 per cent on Friday after the German airline announced the surprise departure of chief financial officer Simone Menne, said a report.

Menne, who turns 56 in October, will resign effective August 31 to “pursue individual career options,” the company said in a statement late Thursday, adding it will choose a successor shortly. Menne, a member of the carrier’s board since 2012, said last year that she eventually wanted to head a company in Germany’s benchmark DAX30 stock index, Bloomberg reported.

“There was no indication that this might happen,” Gerald Khoo, an analyst at Liberium Capital Limited, said by telephone from London. “She is well-regarded by investors. They will want to know why this happened, and why it happened now. It’s unusual given Lufthansa’s history of succession planning.”

Menne has helped chief executive officer Carsten Spohr steer the company through years of restructuring that included setting up low-cost arm Eurowings, as well as cutting benefits and pay for entry-level workers, both of which have been met by fierce opposition from unions. She also helped safeguard the company’s investment grade rating, a rare status among airlines, even with the company’s pension liabilities surpassing €10 billion ($11.3 billion) last year.

Lufthansa shares fell to as low as €11.50, the lowest intraday price since September 2015, and were down 3.6 per cent at €11.57 as of 9:13 am in Frankfurt.

Lufthansa is reining in expansion plans as a glut of plane seats depresses ticket prices and travellers delay bookings amid fears of terror attacks. Capacity growth this year will trail the previous target of 6 per cent, Spohr said in an interview last month. The cuts will come on short- and long-haul routes at Lufthansa’s namesake brand while Eurowings will continue to grow, he said.

As low oil prices boost profit to record levels at Lufthansa and other airlines and spurred expansion, summer capacity plans failed to take into account the impact of terror attacks in Paris, Brussels and Turkey. The company will brief investors about expansion plans for Eurowings on Friday.

Proven Worth

A graduate in business administration, Menne began her professional career in the auditing department of ITT in the U.S. in 1987 before joining Lufthansa as an auditor in April 1989. Ten years later she took over the airline’s financial management and human resources in southwest Europe, rising to the same position for all of Europe two years after that.

Outside Lufthansa, Menne is a member of the supervisory boards of Bayerische Motoren Werke AG and Deutsche Post AG.

“In Simone Menne we are losing an experienced executive who has proven her worth time and again in her long Lufthansa career,” supervisory board chairman Wolfgang Mayrhuber said in the statement.