NAPLES — What started out as an afternoon of fun relaxing on a boat turned into an exercise in how to keep a crashed seaplane afloat.

Maine State Police said the plane crashed about 2 p.m. Sunday on Brandy Pond in Naples.

The crash is being investigated by the Federal Aviation Administration.

This is the second week in a row that the federal agency is investigating a small plane crash in Maine.

“It just came down for a regular landing, but he just kind of veered left and when he did the left wing and pontoon came out, flipping the plane over,” said Bob Peters, one of several boaters who immediately responded to the crash.

According to Peters, who was boating with friends, the seaplane made what looked like a normal landing at first — although a little bit hard. But when the plane attempted to bank left, the left wing and pontoon came out of the water and the plane capsized.

“We thought maybe he was doing a stunt or something,” Peters said.

Two veteran pilots, a man and woman in their 60s, were aboard the craft, a new, eight-passenger amphibious plane delivered to a Brandy Pond-based company within the past two weeks, State Trooper Steven Green said. He did not release their names.

Both made it out of the plane, with one person suffering minor injuries.

Green said the plane was overturned in the water and leaking fuel. “Naples Fire Department has been doing a great job making sure all of that (fuel) is contained by some of the booms they have out there,” Green said.

The two pilots were helping each other to get certified to operate the new aircraft and had done several landings on the pond Sunday, Green said. The crash happened on their last scheduled landing of the day.

A crane company removed the wreckage from the lake late Sunday, Green said.

Peters said that a friend of his was videotaping the plane landing because it was so close to where they were boating on Brandy Pond. The man ended up capturing the entire crash on camera, but turned the video footage over to investigators.

Peters said that the plane had been seen flying around the area for the past few days. He said he was not sure if anyone actually owned the aircraft or whether it belonged to a local dealer and was in the process of being sold.

Following the crash, Peters said that between 15 and 20 boats converged on the scene to offer help before authorities from the state police and the Maine Warden Service arrived. He said that boaters helped the two occupants out of the water and immediately went to task securing the wreckage so that it didn’t sink.

Peters said that boaters tied ropes to the fuselage and pontoons of the plane in an effort to tow the wreck to shore, but authorities arrived and asked that they just keep the plane afloat until a larger crane arrived to remove the wreckage.