The lawyer for grounded Queensland-based airline, Barrier Aviation, says the company has written to CASA urging it to speed up its investigation.
Lawyer Derek Perkins says the grounding is costing the company $28,000 a day.
Mr Perkins says the company is working to resolve as many issues as it can before the matter goes before the Federal Court in February.
"[CASA have] just done nothing for 10 days over the Christmas period and suspended a reputable airline without notice," he said.
"We're really willing to cooperate and help them satisfy their concerns but sooner rather than later.
He says the company is reassessing its organisational structure to achieve air safety.
"We're closely looking at our operations in those bases to see how we can implement and complement them to address the issues raised by CASA."
"It's a matter of understanding all the safety deficiencies within Barrier, so that we can then consider what needs to be done to correct problems," he said.
"We must complete this by February 15 - that's the deadline we're working towards.
"Naturally of course if Barrier wish to bring on these matters sooner they can of course go to the Federal Court."