THE travel tax take for the Government plummeted by 20pc this summer compared to last year as Ryanair threatened to pull more flights from Shannon Airport.
The budget airline said that it would pull a number of flights it operates out of the western airport, unless a 33pc rise in passenger charges confirmed yesterday is reversed.
Shannon Airport director Martin Moroney said that the rise was essential as the facility was loss-making and needed to improve its viability.
The increase, which would add €1.58 to bring a single-trip passenger fee to €6.30, was the first in six years at the airport, according to the representative.
This would bring the charge in line with prices at other regional airports such as Cork, Ireland West Knock, Aberdeen, Southampton, Porto, Gothenburg and Malmo.
Ryanair chief executive Michael O'Leary called on the Department of Transport to intervene and force the reversal of the price increase.
Mr O'Leary said that the charge would serve to decrease Shannon's attractiveness to airlines at a time when its passenger numbers were falling and called on an intervention "before further damage is done to Shannon Airport traffic, tourism and jobs this winter".
The airline said that if these price increases were not reversed then it would shortly announce further flight and traffic cuts at Shannon.
Separate figures supplied by the Revenue Commissioners outline that it collected €1m less in July 2010 compared to the same month the previous year.
In the summer months of May, June and July the Government collected €26.4m on the tax compared with €33m in the same months last year.
When the tax was introduced in 2008, it said that it expected to raise €150m in a full year but later revised that downward to €125m.
Low-cost airline Ryanair has constantly demanded that the Government abolish the departure tax saying that if it did the airline would add more routes in Ireland.
And analysts have said that ultimately the tax could cost the economy around €450m a year as many tourists will stop coming to Ireland.
Figures from the Irish Aviation Authority outline that there were 7,800 commercial flights at Shannon in the first six months of the year, 6,480 fewer than the same period last year.