GOVERNMENT ministers were sometimes refused flights on the government's better jets by the Department of the Taoiseach, detailed itineraries have shown.

Logbooks for the government's €2,950-an-hour Learjet show that use of the aircraft was not always guaranteed.

On one flight from Dublin to Belfast with a return journey to Waterford, Martin Cullen was told he could not use the government's second jet and was asked to use a cheaper Beechcraft airplane instead.

A note in the diary of the aircraft explains: "Now incorporated as part of Beech Mission 68. Use of Lear was not approved by Dept [of] Taoiseach."

On another occasion, the former ceann comhairle John O'Donoghue had been hoping to fly from Dublin to Cork and back aboard the Learjet.

However, the Air Corps said that the airplane was required for training purposes and O'Donoghue was forced to make do with the Beechcraft.

The Beechcraft – which cost €1,770 an hour – was considered the workhorse of the Air Corps and was taken out of commission last year due to age and safety grounds.

Politicians were also on occasion "upgraded" because Defence Forces pilots had to fulfil a certain amount of flying hours on each jet.

For one flight to Copenhagen, Dick Roche had been scheduled to fly aboard the Learjet but was switched to the €7,890-an-hour Gulfstream IV.

The explanation given by the Air Corps was "operational reasons"; the logbook also stated that the Gulfstream needed "flying hours to keep crew ratings up".

Some missions proved extra-costly because two flight crews were involved to ensure none of the pilots exceeded their hours.

On a flight to Lisbon for former taoiseach Bertie Ahern, the Air Corps said that the additional short hop between Baldonnel and Dublin Airport would necessitate a second crew.

The Department of the Taoiseach was asked if it could cancel the two legs between Dublin and Baldonnel, which would mean only a single flight crew would be required.

But the department insisted on the longer flying time and two crews had to be tasked with the mission so that Ahern's arrival point would be closer to home in Drumcondra.

Former taoisigh were also made welcome on the jet. On one flight to Belfast, Albert Reynolds was a passenger according to the itineraries.

He travelled to the North along with Martin Mansergh, Liz O'Donnell, David Andrews and a number of civil servants. The then EU commissioner Charlie McCreevy also made use of the jet twice in 2007.

The logbooks also show how in the early days of the Fianna Fáil and Green government, flights were booked on behalf of environment minister John Gormley.

However, a trip to Luxembourg in June 2007 was cancelled by Gormley's officials, as was a similar trip to Lisbon in September.

Amidst controversy over his ministerial expenses, the Green Party leader defended himself in part by saying he – unlike many others – had never even been on board the jet.