Retired Air Force major general Richard V. Secord, a key figure in former White House aide Oliver L. North's network to arm the Nicaraguan contras, yesterday agreed to drop the appeal of his conviction for his role in the Iran-contra affair, according to court papers.

In a plea agreement with independent counsel Lawrence E. Walsh, Secord last year pleaded guilty to a felony count of lying to congressional investigators and was sentenced to two years' probation.

Secord then appealed a technical ruling previously made by the judge in the case, an action that drew a sharp protest from Walsh, who charged that the appeal was a violation of the spirit of the plea agreement.

If Secord's appeal had succeeded, it could have overturned his conviction.

In response to the appeal, Walsh had asked Chief U.S. District Judge Aubrey E. Robinson Jr. to reconsider dismissing 11 other felony charges against Secord, which had been dropped in exchange for Secord's guilty plea.

According to papers filed by Secord and Walsh, they have reached a second agreement, and Walsh has dropped his request to reinstitute the other charges in return for Secord's decision to withdraw his appeal.