The National Museum of the Royal Navy (NMRN) has started a consultation on proposed redundancies and restructuring following effects of the coronavirus pandemic.
Restructuring proposals include 32 full-time equivalents being reduced from a full compliment of 234, with 82 roles initially placed at risk of redundancy.
The NMRN, which has sites in Portsmouth, Gosport, Yeovilton and Hartlepool, reopened its doors to the public in August.
An enforced closure during lockdown led to it losing 60% of its annual admissions income.
A total of 81% of the museum's income in any normal year is self-generated.
A statement from the museum said: "We fully understand that this consultation continues a difficult period for our staff, many of whom have supported the museum by taking furlough leave, returning to work under flexible furlough and working incredibly hard to reopen our sites in Portsmouth, Gosport, Yeovilton and Hartlepool.
"We also recognise that other staff have worked tirelessly while we have been closed to protect the ships, aircraft and collections that we care for on behalf of the nation.
"The autumn/winter period would not generate sufficient income to recover lost ground even in a normal year.
"Like many in the heritage and museum sector we anticipate that the recovery of visitor numbers will stretch well into 2022.
"It is clear, therefore, that we need to act swiftly and make changes now."
Professor Dominic Tweddle, Director-General, National Museum of the Royal Navy, said: "The hard work and commitment of all staff, as well as the emergency financial support from the Royal Navy in 2020/21, has meant that we have been able to reopen and successfully welcome back visitors.
"The dedication and sheer bloody-mindedness of the staff team and key partners has also meant that despite being closed we have delivered a number of key projects, LCT 7074, the walkway under HMS Victory, the soon to be launched Diving Deep exhibition, telling the tale of HMS Invincible, and the partnership with the Mary Rose Trust.
"I am unbelievably proud of what has been achieved over these last six months and therefore unbelievably sad that this day has arrived," he added.
In July, Mr Tweddle said a "fundamental overhaul" of the NMRN's financial model was required.
An enforced closure during the coronavirus lockdown has led to losses in income for the museum, with changes required to ensure its long-term future, according to its director general.
Final decisions on the restructuring proposals will be made once the consultation is complete.
The museum said its priorities are "the wellbeing of our staff and ensuring that we are best placed to continue to attract more than 1.8 million visitors a year and showcase the ongoing impact of the Royal Navy on the nation’s history and its role on the global stage".
The National Museum of the Royal Navy, established in 2009, tells the story of the four fighting forces of the British Royal Navy: The Royal Marines, the Fleet Air Arm, the Submarine Service and the Surface Fleet.
The Museum Group includes the Royal Naval Museum, the Fleet Air Arm Museum, the Royal Navy Submarine Museum with HMS Alliance, Explosion! The Museum of Naval Firepower, the Royal Marines Museum, HMS Victory, HMS Caroline, HMS M33, HMS Warrior and NMRN Hartlepool, home to HMS Trincomalee.
Cover image: National Museum of the Royal Navy.