A familiar sight outside the Franklin Institute will be missing for a significant period of time, museum officials announced.

The Budd BB1 Pioneer Aircraft was removed on Wednesday from its moorings along 20th Street for a full restoration.

The 1,750-pound plane has been displayed along the building's facade since 1935, making it the second longest-running exhibit at the museum. Only the Baldwin 60,000 locomotive has been at the Franklin Institute longer.

It's also the second museum attraction to be upgraded along the street. A short walk away, museum officials converted an existing sign to digital in August after a lengthy dispute with the city of Philadelphia.

Scheduled maintenance on the plane includes a polish to its original surface, repairs of cracks to the plane's structure and installation of mesh netting to prevent future damage.

Once completed, the plane will return to its position next to the museum's entrance, Franklin Institute President and CEO Larry Dubinski said.

The aircraft holds historical and local significance.

According to the museum, The Edward G. Budd Manufacturing Company decided to build the world's first stainless steel airplane. Entirely built in Philly, the Budd BB1 Pioneer's maiden flight occurred in the summer of 1932.

The company donated the plane in 1935 to the museum where it has been displayed ever since, except for a previous renovation in 1969.

The plane will not be leaving city limits, however, as it will be moved to a facility in Northeast Philly for restoration.

Museum officials said the conservation process will last at least a year.