Airbus is looking to verify preliminary findings on the risks of volcanic ash to aircraft by conducting a test flight in formation with a suitably equipped sampling aircraft.
No evidence of damage to the aircraft or their engines was subsequently found.
But Airbus says that, because the test flights did not sample the atmosphere, the results are only of limited value in terms of determining safe thresholds.
"What we need now is a second aircraft flying in parallel with ours," says the airframer.
"We need to validate the models. Only an aircraft which can measure concentrations can bring a result."
No date has been set to conduct the flights. But Airbus says the test would probably need to be co-ordinated with a specialist organisation, such as Germany's DLR or the UK's NERC, each of which carried out measurement flights after the April eruption.