John Strickland: 'Direct, or blunt, with Willie, what you see is what you get'

Starting with Aer Lingus, which he saved from likely bankruptcy, he took difficult decisions on job cuts and recognised the need to treat competitor Ryanair seriously, learning from its unorthodox approach, not least the requirement to instil a disciplined focus on costs.

Moving to British Airways he saw the necessity for a serious shake-up, dragging it into the increasingly tough competitive environment of the 21st century. Being a premium airline doesn’t mean that cost control can be ignored and this is something which Walsh imbued into its DNA.

There have been challenges, of course, but it’s not by chance that BA’s financial performance is streets ahead of its peers.

Another major achievement while at BA was his promulgation of the transatlantic joint venture with American Airlines, allowing the airline to match what Air France and KLM and Lufthansa were already doing with their US partners.

This is a cornerstone of BA’s success today and something for which previous generations of BA management had not succeeded in getting regulatory approval.

With the establishment of IAG, initially between BA and Iberia, there were many sceptics who argued this was a poor attempt by BA to copy the merger of Air France and KLM and to emulate Lufthansa’s acquisition moves.

Walsh has shaped the group today into a true industry leader, far ahead of its peers and one of the few regular dividends payers to shareholders.

He handed Luis Gallego, his successor at IAG, the task of sorting out Iberia and today it has been transformed financially from loss to sustained profit and in service delivery with a long run as the most punctual airline globally.

Walsh sees IAG as a key industry consolidator and has been skilful in adding valuable acquisitions for the group. BMI, which made losses while owned by Lufthansa, was acquired by IAG, significantly strengthening its Heathrow position.

Returning to where he began, the acquisition of Aer Lingus required a long campaign with Irish politicians and unions to convince them that this would not be a retrograde step.

Walsh stepped up to the plate and today, Aer Lingus is delivering record levels of profitability and growth that could not have been imagined had it remained independent.

So as the Willie Walsh era draws to a close at IAG, he goes out on a high leaving behind a legacy which is the envy of many around the world.

John Strickland is an aviation industry consultant and director of JLS consulting.