A Senate committee looking into the controversial multi-billion-dollar Joint Strike Fighter program has recommended Defence develop a plan B in case the high-tech F-35A aircraft are not ready on time.
The first are expected to arrive in Australia in 2018 and enter service in 2020, replacing the F/A-18 Hornet fleet.
The committee investigating the acquisition said it had listened to concerns about the aircraft's manoeuvrability, stealth capabilities, escape system and other features.
Serious problems led to a re-baselining of the program in 2012.
In a report, the committee said it was the only aircraft able to meet Australia's strategic needs, but retained a "healthy scepticism" towards the assurances about the aircraft, its costs and delivery time.
The committee recommended the Department of Defence develop a hedging strategy in case of additional delays.
It noted the Australian Strategic Policy Institute's advice that the "most sensible hedge" would be to order more F/A-18F Super Hornets.
The committee has recommended the hedging strategy be completed by 2018 and capable of implementation by 2019 at the latest.