IAG chief executive Willie Walsh has raised the prospect of British Airways adding "five or six" second-hand Airbus A380s to its fleet of 12 new superjumbos, describing the the type as a "fantastic" but "inflexible" aircraft.

Used A380s could also, Walsh indicates, be added to fleet of another IAG-owned airline: Spanish flag carrier Iberia.

At the same time, Walsh appears to rule out converting his current seven options for new A380s, saying the price being offered by Airbus is "too expensive". He had previously indicated that he did not see room for additional A380s at BA beyond the 12 ordered.

Walsh told the Airline Economics Growth Frontiers conference in Dublin today: "We have options on A380s but we're not going to exercise them, but we are interested in leasing second-hand A380s. I believe we could look at a further five, maybe six, for British Airways, and possibly make a case for Iberia too."

He says IAG would only be interested in acquiring Rolls-Royce Trent 900-powered A380s, which means that examples leaving the fleets of Malaysia Airlines or Singapore Airlines over the next three years are the most likely sources.

Walsh says there is "no timescale" for acquiring the additional A380s, which would likely replace Boeing 747-400s. "We are not in a hurry. The 747-400 is still an efficient aircraft, especially in the current oil-pricing environment," he says.

BA operates 10 Trent 900-powered A380s, and, Flightglobal's Fleets Analyzer database shows, will take the final two from its original 2007 order in February and June this year.

Acquiring "one or two" A380s for IAG subsidiary Iberia could also make sense because – while operating small numbers of superjumbos would not normally be viable – "the advantage of IAG means we can utilise our scale".

Walsh says IAG is also talking to leasing companies about acquiring second-hand Boeing 777-300ERs, noting that the group's "attitude" to operating used aircraft had changed in the last few years.

Describing the A380 as "fantastic from a customer and connectivity point of view", Walsh says the aircraft comes into its own on "routes where there is a high volume demand but frequency is not critical". Citing the example of Los Angeles, where British Airways has replaced three 747-400s with two A380s, he says: "We are filling them, and the added benefit – which we didn't factor into our original calculations – is that you get back a slot at an over-capacity Heathrow," he adds.

However, he notes that the superjumbo is "an inflexible aircraft that works well on certain parts of the network".

Source: Cirium Dashboard