Gill FitzHugh, of Army Navy, older brother of touring pro Woody FitzHugh, made four birdies and carded one-under-par 70 for the first round led in the 54-hole Northern Virginia Amateur Golf tournament yesterday at River Bend.

District Amateur champion Rob Black of Army Navy and Bill Holmes of Interntional are tied for second at 72.

Stifling heat and newly constructed fairway sand traps kept the scores high on the 6,608-yard layout.

"i think everybody was conscious of the heat," said FitzHugh, who defeated his brother in the 1973 District Amateur Championship.

The 93 competitors had a shotgun start and FitzHugh birdied his first hole, the 16th, with a 10-foot putt. Another key to his round was the eighth hole, where he chipped into the cup from 20 feet for another birdie.

Defending champion Ken Weakley had trouble with a hook on his final hole and finished with 75. Weakley, the starter at Pinecrest, suffered double bogies with three putts at the 10th and sixth holes but kept his round glued together by holing out with a seven iron for birdie on the 405-yard fourth hole. The stocky 25-year old hooked his drive into trees and advanced his second shot only 50 yards. He choked up on his seven iron and punched the ball toward the green and it rolled in.

"As long as you can get a swing at it," Weakley said, smiling.

Tony DeLucca of Chantilly was two under par at one time but bogied three holes on the back nine to finish tied with four others at 73.

The field was cut to the low 40 and ties for today's second round.