NORTH BEND, Wash. -- The ground search for a Florida skydiver whovanished during a jump above Washington's Cascade foothills endedSunday without a sign of the man.

The King County sheriff's officesaid crews combed roughly 9 miles of an area near Mount Si for29-year-old Kurt Ruppert but that the air search would continue.

TheLake City, Fla., man hasn't been seen since he jumped out of ahelicopter at 6,500 feet on Thursday. He was wearing a special wing suitwith fabric under the arms to allow him to glide like a flyingsquirrel.

The jumpsuit is brown and green, which will likely blend into the terrain.

Crews narrowed their search area Saturday, based on data from Ruppert's cellphone and the helicopter's flight path.

Authoritiesknow the flight pattern of the aircraft, but a number of factors havemade it difficult to find Ruppert, including the suit, which could allowhim to travel large distances in a short time, sheriff's Sgt. CindiWest has said.

Searchers were hoping Ruppert was stuck in a treewith his parachute or perhaps lost in rugged state-owned land around the4,200-foot high Mount Si, which is east of Seattle, West said.

MountSi, which is covered with trees on steep slopes, is popular with hikerseven though it can be treacherous. West said the searchers have checkedareas that could reached by foot.

Ruppert was skydiving with twofriends, and they were taking turns jumping from the helicopter. Thefriends were waiting at a grassy landing area, but no one saw whetherRuppert's chute deployed.

Friends say Ruppert has been skydiving seven or eight years and is good at handling a wing suit.