There are some who would say that The Spirit of St. Louis is dead -- that the age of the lone man in a tiny airplane conquering vast distances has long ended.

Those people have not met Alan Gerharter, a 27-year-old pilot from Medford, Ore.

Early Monday evening Gerharter touched down on Runway 15 at Washington National Airport, shaving an astounding three hours off the record for a cross-country flight in a single propeller aircraft. Gerharter and his Mooney 231 LR had made the nonstop trip from San Francisco -- 2,431 miles -- in 8 hours, 4 minutes and 25 seconds.

Yet Gerharter's welcome was hardly that of a hero. In fact, hardly anyone, with the exception of a few airplane mechanics and a Washington accountant was on hand for his arrival.

One of the few who knew it was wise to be prompt was Mal Gross, a 45-year-old accountant for Price Waterhouse and, more importantly, the previous holder of the single-prop record, which he set on Jan. 1, 1977. Gross, who lives at 1010 Shipman La., McLean, then crossed the country in 11 hours, 7 minutes and 48 seconds.

On Monday, however, all other interested parties appear to have been taken by surprise, not to mention being stunned by Gerharter's swift arrival.

"Mal and I were drinking coffee when the photographer showed up," the young, bespectacled aviator said yesterday with mild amusement.

There were plenty of doubters at National Airport when Gerharter filed his flight plan at the break of day Monday in San Francisco.

"These flight plans have to be pretty precise," the young pilot said. "When I told Washington I was planning on 8 hours . . . Well, they weren't quite ready for that.They insisted that I talk with their air traffic controllers. 'Do you know how far Washington is?' they asked."

Gerharter smiled modestly and said he cannot recall what his response to the controllers was.

The chief flight instructor for a small charter plane company in Medford, Gerharter said the idea of making the flight came to him a year ago.

About six months ago with his employers' encouragement he took up the project in earnest, devising ways to streamline the small Mooney 231 so it would be most efficient when airborne.

"I was excited by the thought of becoming a world-record holder," Gerharter said, "but I was also interested in deomonstrating the efficiency of this plane. Even at these speeds (302 miles per hour at 25,000 feet for most of the trip), I was getting 24 miles to the gallon."

Once renovations to the plane were well under way, Gerharter mailed $600 to the Washington-based National Aeronautics Association to sanction his attempt on the record. This meant that for a 90-day period no one else would be permitted to challenge it.

Weather is the all-important ingredient to making a record-breaking flight in a light plane, and as a result, Gerharter became a connoissur of wind reports.

"I needed very accurate wind information and I got it mostly from The Weather Bank in Salt Lake City," he said, referring to a private weather forecasting service he called "much better than the National Weather Service."

When indications were that the winds from the west were strong and the nation's skies were mostly clear, Gerharter hurried to San Francisco, filed his flight plan and took off, leaving his 27-year-old wife Patty on the ground.

In his eight airborne hours, Gerharter flew over Pryce, Utah, Boulder, Colo., Champagne, Ill. and then edged south to Clarksburg, W.Va. At the halfway mark, he lost his primary navigation radio. "After that it was all compass and clock," he said brightly.

Like the Lone Eagle who kept up his strength by eating his sandwiches over the Atlantic, Gerharter nibbled on granola bars and drank from a Thermos of coffee as he flew.

He also took deep gulps from small oxygen tanks, necessary cargo when traveling at 25,000 feet in a nonpressurized plane.

Gerharter has been flying for nine years. "I just got interested. Model airplanes as a kid, that sort of thing. I got my private license at 18 and I've been flying ever since," he said.

Lindbergh has always been one of his heroes. "I've read all his books and I greatly admire him. Lindbergh's confidence behind an engine is an inspiration to all pilots," Gerharter said yesterday shortly before he headed for the Air and Space Museum to commune with The Spirit of St. Louis in person.

Gerharter plans to leave the Washington area on Thursday. Since he won't be in such a rush this time, he plans to stop in Peoria, Ill., and Hays, Kan. "I'm going to visit my grandmothers" he said.