Aer Lingus has reported a strong increase in passenger numbers for March, but filled a lower percentage of seats as its expanded its route network.

Total passenger numbers were 898,000, up 15.4% on the same month last year. Short-haul numbers were up 15.7%, while long-haul showed a 13.4% increase.

The total load factor, or percentage of seats filled, was 75.3%, down from 78.1% in March last year. The short-haul figure rose by just over a point to 72.2%, despite a 22.6% increase in capacity in the period, but long-haul fell 7.3 points to 72.2%.

Aer Lingus's long-haul capacity has increased by 31.5% over the past year with the introduction of two new planes and the launch of three new routes under Open Skies.

For the first three months of 2008, Aer Lingus passenger numbers are almost 14% ahead at just over two million, but the total load factor is down 5.3 points at 74.2%, mainly due to an 11-point long-haul decline.

Meanwhile, Aer Lingus said that bookings on its Belfast routes are significantly ahead of schedule and that its new Northern Ireland service is on target to be profitable by the end of the year.

The airline stopped its Shannon to Heathrow link in January and switched the Heathrow and other connections to Belfast. 

According to the airline's commercial director Enda Corneille, the company will make its 250,000th customer booking from Belfast this week, with the target of half a million passengers on track.

Aer Lingus now has ten routes operating from Belfast to destinations including Amsterdam, Paris, Barcelona and Nice.  It says it is drawing customers from across the community in Northern Ireland and getting business from border areas, such as Donegal. 

It bases three aircraft in Northern Ireland, but there are no short or medium term plans to launch transatlantic services from Belfast. 

The company is due to shortly announce its Belfast winter schedule - earlier than normal.  The strategy suggests that Aer Lingus is determined to prove to shareholders and the marketplace that the controversial move north is a success.