Details of a Heathrow directors’ bonus scheme that is partially linked to their success in securing approval for a third runway should be published, according to a leading opponent of the airport’s expansion. 

John Stewart, chairman of the Heathrow Association for the Control of Aircraft Noise (Hacan), said the west London hub’s apparent “secrecy” over the scheme meant the bonuses had become an “issue”.

Heathrow started a new bonus plan early last year that includes as a target winning approval for its controversial £17.6 billion third runway, the Sunday Telegraph disclosed at the weekend.

Heathrow had said in February that incentives for its executives were not linked to airport expansion.

Heathrow disclosed the scheme in its 2015 annual report but it went unnoticed until now, the Telegraph reported.

The report provides few details of the plan, although a Heathrow spokesman said last week that targets for profits and passenger satisfaction must be met before the third runway element can be considered.

It is thought that airport expansion accounts for a maximum of 8% of the incentive scheme, according to the newspaper.

Stewart said: “Any company would expect to reward its employees. Their initial secrecy I think has made it an issue that otherwise it wouldn’t have become.

“Now that this has come out it would be in everybody’s interests including theirs to give more detail and be more transparent about it.”

A Heathrow spokesman said: “In common with most private companies, Heathrow has a senior management incentive scheme linked to meeting a number of strategic priorities, with the expansion element not awarded unless challenging customer service scores and company profitability metrics are first achieved.” 

Heathrow is vying with rival Gatwick for government approval  to build a new runway.

A decision on which airport to expand was delayed from December until this summer.

The government said it needed to carry out more work on the environmental impact of another runway before choosing between Heathrow and Gatwick.