About the only surprise from Pat Shanahan's decision to resign as executive chairman of the Shannon Airport Authority (SAA) earlier this week was that it took so long.

Shanahan was appointed chairman-designate by former minister for transport Séamus Brennan in October 2003 as part of the proposed break-up of the then Aer Rianta. Delays in enacting the legislation meant that it was the guts of another year before the SAA actually came into being, albeit under the umbrella of the newly formed Dublin Airport Authority (DAA).

Shanahan should have taken off his seat belt there and then and headed for the exit steps.

Three years on from that milestone and the Co Clare airport's separation from DAA is still waiting for clearance, this time from recently installed Minister for Transport Noel Dempsey.

In the meantime, Shannon has come through painstaking negotiations with workers at the airport over a generous €36 million voluntary severance package.

It has also lost its prized access to Heathrow with Aer Lingus transferring the slots to its new base in Belfast.

The revelations that the DAA and Department of Transport had kept Shanahan in the dark over Aer Lingus's plans clearly pushed him over the edge.

Shanahan is a loss. Within months of the SAA being set up, a deal had been cut with Ryanair to open 14 new routes. The low-fares airline is now by far the biggest carrier at Shannon.

In May 2004, Shanahan told members of the Mid-West Regional Authority in Co Tipperary that Shannon could double its traffic to four million by targeting low-cost carriers. Last year, it handled 3.6 million passengers.

On the downside, Shannon still relies too heavily on US military traffic heading east and it might struggle to retain its transatlantic traffic when the stopover is axed in April.

Shanahan wants the SAA to be given its independence immediately. It is unlikely that there will be too many dissenting voices in the DAA. Over to you, Minister.