Airbus believes it will not drop production rates during the transition to the A320neo, but appears increasingly reluctant to raise the monthly single-aisle rate beyond 42, in order to avoid jeopardising the switch.
Deliveries of the A320neo are scheduled to begin in October 2015 and Airbus states that it will have the capacity to deliver only the re-engined type from 2018.
Chief executive Fabrice Brégier says the airframer "doesn't need to accumulate many [regular A320 variant] orders" to plug slots in the transition between 2015 and the end of 2017.
"We are confident we won't drop production rates during the transition," he says. Brégier adds that there has been "zero drift" on the A320neo programme.
Chief operating officer for customers John Leahy estimates that the manufacturer will sell 200 regular A320s over 2013. Last year it secured net orders for 261.
Airbus increased its A320 production rate to 42 last year, and had been exploring a possible rate rise to 44.
But the airframer is concerned over the ability of the supply chain to keep up. Although it will have additional capacity from the new assembly line in Mobile, Alabama, Brégier points out that final assembly "won't be the bottleneck" for any production increase.
Airbus chief operating officer Günter Butschek says the airframer "got hit by a couple of supplier issues" on single-aisle production, simply through the rate increase. With higher production rates, problems can start arising from the lowest tiers of the supply chain.
"Very often it's not a big part which is missing," he says.
He attributes these partly to a "backlog of investment" with some companies while some others had "put their bet on the wrong assumptions".
While the airframer has been able to cope, and stabilise the production, Butschek says: "The disadvantage is that this is still all reactive. We need to learn to move to a proactive and preventative approach."
He says he does not want Airbus to be "fire-fighting", adding: "The more energy we have to give to a crisis, the more difficult it is to go to the next level of excellence."
Butschek says that stabilising the chain means giving suppliers a "long-term and credible forecast", and points out that the timeframe for a rise in monthly rate to 44 A320s would risk conflicting with the transition to A320neo assembly.
"We would put in a lot of effort for two aircraft and compromise the [A320neo] transition," he says. "It makes more sense to stick to the rate as-is and put in place a [transition strategy]. We'll take the pressure off, and focus."