For the first time in nearly a half-century, the Franklin Institute's Budd BB1 Pioneer airplane, a fixture along the Benjamin Franklin Parkway, actually moved.

It did more than move. This biplane floated - up from its display posts in front of the building. It twirled slowly in the sun about 20 feet in the air, and then gently descended to the ground.

Bump.

The Budd plane is one of the institute's great artifacts, conceived and manufactured in Philadelphia, and given to the institute by the Budd Manufacturing Co. in 1935, a year after the Parkway building opened. It had remained on public display ever since - with the exception of a 1969 cleaning - until Wednesday.

The small biplane was hoisted in the morning from its perch by a giant crane. Over the next day or so, it will be dismantled and removed to a warehouse for cleaning and conservation.

The plane has some pocks and holes, and shows a distinct familiarity with birds and their leavings.

The Budd company began as a metal fabricator, manufacturing for the rail and automotive industries. Karen Elinich, director of science content at the institute, said Budd badly wanted to break into the aviation manufacturing business in the early 1930s and developed a novel welding technique to manufacture the small plane from stainless steel.

"This is really a prototype," Elinich said. "They hoped this would give them a whole new avenue of business."

The 1,750-pound Budd Pioneer flew across the country. It flew across the Alps. It logged 1,700 hours in the air, demonstrating the validity of the Budd manufacturing process.

But it failed to attract business.

In 1935, the company presented the plane for exhibition - in virtually the same spot it has occupied since. Only the institute's Baldwin 60000 locomotive has been on longer continuous exhibit.

For the 1969 cleaning and restoration, the plane was taken back to the Budd plant in the Northeast and restored by retired workers who had built it. Budd shuttered its last operations in 1987.

Alfred "Fred" Hagen, president of Hagen Construction and an airplane aficionado, was on hand Wednesday to watch the beginning of the removal. The Pioneer will be taken to Hagen's Bensalem warehouse for conservation evaluation.

"I've salvaged aircraft in the South Pacific," said Hagen, a licensed pilot. One of those belonged to a great-uncle who went down in New Guinea in a B-25 during the Second World War. Hagen has found several other planes and the remains of the American airmen who went down with them.

"It's very emotional for me," Hagen said. "This [Budd Pioneer] is from the early days of aviation. Franklin Roosevelt was president. So it has been through a lot. It's one of the great iconic sights of Philadelphia."

Larry Dubinski, president and chief executive of the institute, said the plane would be in conservation for about a year, returning to its longtime perch next fall.

He lifted a glass high to toast the plane.

"Here's to the dramatic liftoff," he said.

215-854-5594@SPSalisbury