Runway reinforcement needed as carrier decides to base big twin at Paris airport

Paris airports operator Aeroports de Paris (ADP) is discussing options to reinforce the runway at the capital's Orly airport after discovering that it could be damaged by intensive operations by Air France's Boeing 777-300ERs.

Air France – which already operates 777-300ERs from Paris Charles de Gaulle – is planning to base seven at Orly from May next year to be used on dedicated routes to French territories.

But while Charles de Gaulle's runways are strong enough to withstand frequent operations by larger aircraft, Orly's will need upgrade work to handle the 777s. Paris Orly has three runways, the longest of which is the main 25/07 strip. Air France says: "Examination of the resistance values published for the longest runway at Orly Airport did not appear to suggest difficulties in receiving Air France's 777-300ERs.

"It appears that the actual technical state of the pavement nevertheless requires reinforcement before intensive use of these Boeings."

Air France says it is in talks with ADP regarding measures to strengthen the airport's surfaces, and that there is "enough time" to carry out the work before Air France introduces the aircraft to Orly next year.

Each of the two main-gear legs on the 777-300ER supports 46% of the aircraft's weight and this is spread between six wheels. The 777-300ER has an all-up weight of 352t.

In contrast the Boeing 747-400ER, while having an all-up mass of 414t, carries its weight on four main-gear legs each supporting 23% of the aircraft's weight. Each main-gear bogie has four wheels.

This means that the 777-300ER, despite being the lighter of the two, potentially concentrates a greater load on each individual wheel.

Air France is not intending to alter its plans to base the 777s at Orly and insists ADP should bear the responsibility for funding the reinforcement work.

ADP declines to comment on the issue of financing any alterations, but says that the airport "was not supposed to handle" frequent operations by the largest aircraft types, expecting such services to be routed primarily through Charles de Gaulle.

"There's a big difference between handling large aircraft once or twice a year, and several times a day."

DAVID KAMINSKI-MORROW/LONDON

Source: Flight International