(Reuters) - Airline group Air France-KLM on Thursday reported a bigger-than-expected drop in its quarterly operating result, impacted by the Paris Olympic Games and unit costs.

The French-Dutch group's operating result decreased by 162 million euros to 1.18 billion euros ($1.27 billion) compared to last year, and fell short of the 1.24 billion euros mean estimate expected by analysts in a company-provided consensus.

The airline noted that excluding the Paris Olympic Games unit revenue impact of 160 million euros, the operating result is equivalent to that of last year.

"Beyond their financial implications, the Olympic Games provided a unique platform to demonstrate the Group's operational expertise and capabilities while offering unparalleled visibility for France as a destination," Group CEO Benjamin Smith said in a statement.

The negative Olympic Games impact was seen as avoidance of Paris by the international markets while travel between the city and other destinations was also below the summer average as residents in France postponed their holidays, the company said.

Its quarterly revenue rose 3.7% to 8.98 billion euros, driven by increased capacity and strong underlying demand.

While demand has remained stable, maintenance costs, adverse weather, air traffic control issues and disruption in the Middle East have continued to weigh on carriers.

The group said it expected a unit cost - the average cost of flying an aircraft seat one mile - increase of close to 3% for 2024 compared to 2023, up from the previously expected +2%.

It also said it expected its net capital expenditure for the year to be at 3 billion euros, against the previous below 3 billion euro estimate.

($1 = 0.9315 euros)