The £15 million Government jet is undergoing a 10-week maintenance overhaul in the US at a cost of £350,000 to the taxpayer.
This means that ministers with business abroad will have to travel on commercial aircraft for the next two months. In some cases private aircraft may be leased to transport the Taoiseach and Cabinet members abroad.
A spokesman for the Department of Defence confirmed last night that the executive Gulfstream IV, acquired in January 1991, has been with the Gulfstream Aerospace Corporation in Savannah, Georgia, since July 12th undergoing a "standard maintenance overhaul". He said the jet would return to the State at the end of September. "This is routine and in accordance with maintenance guidelines for this aircraft. There is nothing more to it than that."
A Government spokesman said because the jet was unavailable, a specially hired "air taxi" would transport the Taoiseach to Sarajevo tomorrow for the EU heads of state meeting to decide a rebuilding programme for the Balkans.
Mr Ahern will fly out in the morning and return to Dublin that evening. Because Sarajevo airport is restricted in the amount of aircraft it can accommodate, heads of government travelling may be forced to "plane-share". There is a possibility that Mr Ahern may stop in Bonn to complete his journey with the German Chancellor.
The spokesman said it was not known yet exactly what the travel arrangements were. "We obviously have timed the overhaul of the Gulfstream with a quiet time for Government business. If ministers have to travel abroad in the next few months, they will use commercial airlines or the Department of Defence will hire a suitable aircraft if the need arises."
The State also owns a smaller aircraft, a Beechcraft. It carries up to four passengers but does not have a long-range capability.
The Gulfstream IV can fly up to 5,000 miles, easily making, for example, Dublin to Washington. It can carry up to 14 passengers.
The Gulfstream cruises at 530 m.p.h. and carries four crew, including a cabin steward. It is equipped with a high-level communication system and its executive features include a comprehensive audio-visual system.
When it was acquired in 1991 the purchase was described as a "shameful waste of public money" by opposition TDs. At the time the State was the first EU country to upgrade from the older Gulfstream III to the much improved Gulfstream IV.
Even though the jet is now almost nine years old, the Department of Defence spokesman stressed there were no plans to change or upgrade it.
Over the years the Gulfstream IV has brought ministers as far afield as Japan, Singapore, Alaska and South Africa. The most frequent flyers are the Taoiseach, Mr Ahern, the Tanaiste, Ms Harney, and the Minister for Foreign Affairs, Mr Andrews. The jet is from time to time available to the President for trips abroad.