Two airplanes in an amateur flying group collided over Delaware Bay this morning, killing one pilot and leaving another missing, investigators said.

The crash took place shortly after 10 a.m. over Breakwater Harbor, near Cape Henlopen State Park and the terminal for the Cape May-Lewes Ferry, and was witnessed by many weekend beach visitors, emergency officials said. There were no reports of injuries on the ground.

The airplanes in the crash were in a group of six that took off from Sussex County Airport in Georgetown, Del., earlier in the day, according to the U.S. Coast Guard, which is involved in the recovery effort. All six planes were part of the Vultures Formation Team, consisting of pilots who build experimental aircraft and fly them in air shows. Residents said the group frequently practices in area skies.

The pilot who was killed was identified by Delaware State Police as Jay Blum, 39, of Berwyn, Pa., near Philadelphia. His body was found in the water "in the general vicinity of" wreckage from the plane, said Cpl. Jeff Oldham, a police spokesman. Oldham said much of the wreckage had remained on the surface of the water.

Police withheld the name of the second pilot. The search for his body was suspended at 6 p.m. because of water conditions and will resume today, Oldham said. His plane has not been found, the spokesman said.

Coast Guard spokesman John Edwards said the National Transportation Safety Board will conduct an investigation into the crash.

Witnesses said they saw the formation of six planes approach and perform a flying routine that involved half the group flying at, and then under, the other half. One of the planes appeared to misjudge its altitude, and in trying to avoid one of the oncoming planes wound up touching its wings.

"The next thing I knew I saw the one plane clip the other, and before you knew it they were both in the water," said Jesse Tipton of North East, Md., who was enjoying a cup of coffee on the patio of his beachfront condominium when he saw the crash. "I was shaking. I couldn't believe it happened."

Jacqueline Roderick, 19, of Richmond said she saw a chunk of what appeared to be part of a wing fall out of the sky, soon followed by both planes.

Nhat Nguyen, 25, of Great Falls was kayaking so close to the crash site that he heard the planes hit the water. He said it sounded like a gunshot. He said all the motorboats in the area converged quickly on the debris field.

Roderick said she saw the body of one pilot picked up by a boater.

The crash rattled weekend visitors and summer residents of the historic beach town. At the ferry terminal, gathered in front of the windows and behind police tape, pointing to the helicopters, boats carrying divers and police walking along the waterline. Just down the street, fishermen lined the pier and talked to each other about the stunt that went wrong.

The Vultures' formation flying is accompanied by smoke and patriotic music, according to the group's Web site. The fliers had performed July 4 in Eagles Crest, Del., and were next scheduled to perform at a hot-air balloon festival in New Jersey at the end of the month.

The group's Web site lists Ralph D. "Mustang" Morgan as the builder and pilot of one of the planes involved in the crash. Morgan flew a Van's RV-8, a fixed-wing, single-engine aircraft that is classified as experimental by the Federal Aviation Administration, according to agency records. He finished building his plane, named "Problem Child," in 2000 and has been flying with the Vultures for four years.

At Jimmy's Fly-In Grille, just off the runway at Sussex County Airport, manager John Lemieux, 42, said Morgan and his teammates were frequent customers. Sometimes they would come in after a practice and watch videotapes of their performance at the bar.

"They were here every weekend. It was a little club they had," Lemieux said. Morgan and some of the other pilots were there Sunday morning.

The other plane involved was a Rutan Long-EZ, also a fixed-wing, single-engine aircraft rated as experimental, an FAA airworthiness classification given to amateur-built kit airplanes. It is registered to Ace Aero LLC in Bryn Mawr, Pa. According to the Vultures' Web site, the aircraft is piloted by Blum, a commercial pilot and sales manager for a textile company.

The two airplanes are considered "kit" planes because they are assembled by their owners. They are inspected for airworthiness by the FAA during assembly, said Kathleen Bergen, agency spokeswoman.

Staff writer Martin Weil contributed to this report.

Authorities gather at a dock near the Cape May-Lewes Ferry after surveying the wreckage of a plane off of Cape Henlopen State Park in Lewes, Del.