One of Tom Ratliff's flying buddies cautioned that morning about putting too much gas in the tank, which sat right in front of the cockpit. Others suggested that maybe someone else should take the nifty little airplane up on its first flight. Ratliff was 80, after all, and had little time in a "tail dragger" like this.

But the sleek aluminum Hummel Bird was Ratliff's sweetie. He had spent years building it from scratch in the workshop behind his house. His wife, Becky, had even done some of the riveting. Besides, Ratliff was a retired NASA engineer and a seasoned pilot.

So last Tuesday, the other silver-haired Eastern Shore flyboys stood in the shade of the hangar with their video cameras as Ratliff bounced down the grass airstrip outside Salisbury, Md.

The plane started to porpoise as soon as it was airborne. Then it went into a steep climb, stalled and plunged into a right-hand swan dive.

"Oh [expletive]!" someone said. And in a second, Ratliff and his silvery bird were down in the cornfield off the end of the runway.

Tom Ratliff hadn't exactly told his wife he was taking the Hummel Bird up for the first time when he left his house outside Salisbury at 8:30 that morning. She knew he was heading over to Davis Field, where she had helped him haul the partly assembled airplane on a boat trailer last winter.

He had spent long, sometimes frustrating hours out in the back workshop building the main parts of the airplane from plans. This was no "kit" plane, whose parts come with it. With the Hummel Bird, you bought the plans for about $130 and then went out and got the tools and the materials.

It was smaller than a car, weighed less than 300 pounds empty and had a top speed of about 135 mph. It was powered by half of a Volkswagen engine and cost a little more than $2,000 to build. "Poor man's airplane," Morris Hummel, 90, the man who designed the plane in 1980, said last week. "The guys that's got them love them."

Ratliff's model was a tail dragger with an old-fashioned rear tail wheel instead of a nose wheel and the standard tricycle landing gear that most airplanes have. Tail draggers could be tricky to handle, especially on takeoff, and Ratliff had recently practiced in some.

The plane had a single seat and a big bulbous canopy that made it look like something from the Jetsons. But it was so small that it would have flown 8 mph slower in the rain, Hummel said.

It was classified as experimental by the Federal Aviation Administration, and there was a cachet to flying and, especially, building something experimental.

"There's nothing greater than flying something you've built," said Ken Lennox, a flying buddy of Ratliff's who witnessed the crash last week. "You get a bunch of sheet metal and hammer it together. It's like a woman when she has a baby, nine months of waiting, then agony, and this little thing comes along."

But flying a "home-built," especially the first time, can be hazardous.

"You're a test pilot," Lennox said. "You're testing a totally new airplane. Of all the [home-built] experimental plane crashes, a high percentage take place on the first flight. Once you get by the first flight, it's downhill."

Lennox, who once lost the canopy in his home-built experimental Zodiac in midair, had asked Ratliff to let him know when he planned to take the Hummel Bird up the first time. The two were part of a group of local pilots, many of them retirees, that gathers every Saturday morning at the Arby's on Route 13 in Salisbury to talk about flying.

Many were affiliated with the local chapter of the Experimental Aircraft Association and practically lived at airfields or in the skies over the Eastern Shore, which is gorgeous flying country and has plenty of open fields in which to land if you get into trouble. In such cases, you wanted a nice soft soybean field, they say. Corn, high like it is now, will rip up a small plane.

Ratliff, the son of a mining company accountant, had grown up in the coal country of Virginia and Kentucky during the golden age of aviation. As a kid in the 1930s, he had a scrapbook with pictures of airplanes. He had entered the Army during high school with dreams of flying for the Air Corps. But he got airsick easily, his wife said, and World War II had ended by the time he made it overseas.

He was a wizard with numbers, however. And when he got home, he finished high school, received college degrees in engineering and mathematics and wound up with NASA's Goddard Space Flight Center designing satellite components.

He also fulfilled his dream and learned to fly. He once told his wife that whenever he saw an airplane, he felt like a kid again. He flew whenever he could. He flew across country. He towed a banner over a stadium at a ballgame in Baltimore. "We'd fly to Easton for a doughnut or breakfast," his wife said in an interview at their home Friday. And since his retirement in 1987, his final aviation challenge, it seemed, was to build and fly his own airplane, she said.

On Monday night, Ratliff telephoned Lennox and told him he was going to fly the Hummel Bird on Tuesday morning. Becky Ratliff said she believes her husband didn't tell her because he didn't want her to worry. She had her concerns. "It was a very small plane," she said. She had asked whether it was feasible for him to wear a bicycle helmet in the tiny cockpit. Another relative wondered about a parachute. Ratliff could take neither.

The next morning, Lennox flew from the Salisbury airport to meet Ratliff at the rural strip near Pittsville where he kept the Hummel Bird. Another friend from the Arby's confabs, Mike Gray, also flew in. A third friend, Charles Collier, drove. Someone brought a fire extinguisher, just in case. But no one was expecting disaster, and Lennox and Collier had their video cameras.

The trio recalled in interviews that Ratliff, who was clad in shorts, sneakers and a polo shirt, was very focused as he prepared the plane. Nobody said a lot. Gray mentioned the gasoline. Ratliff said he wouldn't put too much in.

The men took the plane to a ditch by the runway and lowered the tail to see whether the engine ran properly at a steep climbing angle. It did.

Ratliff closed the cockpit. He made several fast taxi runs. It was about 10:30, and Lennox and Collier headed for the shade with their cameras.

Ratliff taxied to the end of the runway and started his takeoff. He was airborne quickly and was down almost as fast. There was no fire, just the sound of the impact from across the field. Lennox and Collier lowered their cameras and stared. "I couldn't believe what I was seeing," Lennox said. The whole thing took about 30 seconds.

Lennox and Gray hurried into the cornfield but couldn't find the wreckage. Lennox fell down among the jagged stalks. Gray rushed back to his plane, took off and quickly spotted the Hummel Bird. He radioed the Salisbury tower for help, then landed, and he and Lennox reached the crash site.

They found Ratliff still strapped in his seat. The plane had gone in hard, headfirst, and the men could see that Ratliff was dead. Gray felt for a pulse. There was none. The men wondered whether they should perform CPR but were afraid to move their friend.

In the distance, they could hear sirens. Soon the fire and rescue crews were on hand. A state police helicopter landed, and one from a television station hovered overhead. The three old aviators were stunned and unsure what to do. They drifted away from the crowd. "We kind of bugged out," Lennox said. Collier got in his car. Then Lennox and Gray got in their planes and flew home.

Ken Lennox, a flying buddy of Tom Ratliff's, looks at papers and photos of planes with another friend, Charles Collier. Both men witnessed the fatal crash. Tom Ratliff in Florida in about 1989. His small plane crashed last week on the Eastern Shore. Lennox photographed Ratliff taking off Tuesday in his Hummel Bird.