Two of Airbus SE’s flagship A380 superjumbos are headed for the scrapheap after a search for new operators failed to secure firm bids.

Negotiations with British Airways, Iran Air and Hi Fly, a Portuguese charter specialist, ended with no deals struck, German investment fund Dr. Peters, which manages the planes, said in a statement to shareholders.

The double-decker jets, which had an original list price of about $250 million, should now be broken up and their parts sold off, according to the investor, which said the components could generate $80 million per aircraft in revenue. Fund holders will be asked to approve the move at a meeting on June 28.

Singapore Airlines Ltd. returned the A380s after their 10-year leases expired and Dr. Peters has been seeking new operators since mid-2017. Superjumbo sales have weakened as carriers opt for twin-engine wide-bodies that burn less fuel, and there is no established second-hand market for the planes, which might otherwise be expected to fly for at least another decade.

“We are sure that, with this concept, we can satisfy and even exceed the expectations of our shareholders,” Dr. Peters said of the breakup plan.

The firm said in November that it would store A380s at Tarbes in the foothills of the French Pyrenees as it sought new operators. A further two aircraft are due to return from Singapore Air in coming weeks. The fifth plane coming back from the Asian carrier, owned by leasing firm Doric, may still go to Hi Fly.

Airbus declined to comment on the recommendation from Dr. Peters that the first two jets be scrapped, reiterating that it remains “confident in the secondary market for the A380 and the potential to extend the operator base.”

The manufacturer won a lifeline for the superjumbo with a January order for 20 new planes from Emirates, the only airline to have made the model a central plank of its fleet. The deal will extend production through 2029 should the Dubai airline also take up options for 16 more aircraft, by which time Airbus is betting that overcrowded airports might spur a sales revival.

Boeing Co. 747-400 jumbos operated by British Airways typically date from 1990, according to the Ascend Worldwide database, with some slated to remain in service until 2024, indicating a lifespan of close to 35 years.

The A380 has won a total of 331 orders, with 226 planes delivered as of April 30, according to the Airbus website. While that suggests a backlog of 105 aircraft, some of those commitments date from many years ago and may never be delivered.