ITV News has been told that the squadrons have been working over-time and are having to cancel leave as they embark on back to back tours to Afghanistan and Libya.
The combination of stress and fatigue is potentially dangerous for those in charge of powerful fighter jets.
The causes of the crash are to be fully investigated in due course.
A vessel has gone out to the crash site to locate the wreckage ahead of a salvage operation.
More top news
Police have arrested four men in connection to the suspected terror-linked murder of a police worker in Sydney.
Volkswagen could start recalling cars containing emissions cheating software in January, according to the firm's new chief executive.
A toddler survived for days on his own after his mother collapsed and died as she fed his one-year-old brother - who also choked to death.