Public defender Tony Miles, Hughes's attorney, entered the plea before U.S. Magistrate Judge Alan Kay. Hughes faces six charges, including violating the registration requirements for an aircraft and national defense airspace.
Hughes made no comment during the hearing, but told reporters afterward that Congress had to reform campaign finance laws.
"The purpose (of the flight) was to get Congress to work for the people and not for special interests," he said.
Hughes said he was open to a plea agreement with prosecutors. He held up a mock U.S. postal stamp with his picture on it presented by a handful of supporters who shouted: "Thank you, Doug."
Hughes was arrested after piloting the craft from Pennsylvania and landing on the west lawn of the Capitol as police and tourists looked on. He was carrying a letter for each of the 535 members of Congress.
If convicted of all charges, he could be sentenced to up to 9-1/2 years in prison. Aircraft are banned from flying in the area of the Capitol and White House without permission.
Hughes is charged with lacking a pilot's certificate or registration for the craft. Hughes owned the gyrocopter but it carried the unauthorized logo and emblem of the U.S. Postal Service, the indictment said.
The indictment includes a forfeiture allegation seeking a judgment for his gyrocopter, which has been seized by law enforcement. A gyrocopter resembles a helicopter, but has an unpowered rotor and separate propeller.
Hughes was on administrative leave from the Postal Service at the time of the incident. He has been free on personal recognizance with restrictions on his travel since a court appearance on April 16.
Kay agreed to a motion by Miles that Hughes' house arrest be eased to allow him to travel within the Florida county where he lives, Hillsborough. Hughes must also wear a GPS-enabled ankle bracelet.
Reuters
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