Pioneering astronaut Walter "Wally" Schirra, the only man who flew in all three of America's first human space projects - Mercury, Gemini and Apollo - died Wednesday night. He was 84. Schirra's family reported he died of natural causes.

Schirra was one of America's original seven astronauts, selected in 1959, and was commander of the first crew to fly into space aboard an Apollo capsule, Apollo 7, following the tragic launchpad fire that claimed the lives of the crew of Apollo 1.

"With the passing of Wally Schirra, we at NASA note with sorrow the loss of yet another of the pioneers of human spaceflight," NASA Administrator Michael Griffin said. "As a Mercury astronaut, Wally was a member of the first group of astronauts to be selected, often referred to as the Original Seven."

Schirra's first space flight was piloting the fifth Mercury mission on Oct. 3, 1962, orbiting Earth six times in 9 hours and 13 minutes. During the flight he took hundreds of photos of Earth and space phenomena. Schirra's capsule, Sigma 7, splashed down only 5 miles from the recovery carrier.

During his 11-day Apollo 7 flight, which began Oct. 11, 1968, he and fellow crewmembers Walt Cunningham and Donn Eisele tested the Apollo systems and proved Apollo was ready to take astronauts to the moon.

"We shared a common dream to test the limits of man's imagination and daring," Schirra wrote of America's early astronauts. "Those early pioneering flights of Mercury, the performances of Gemini and the trips to the moon established us once and for all as what I like to call a spacefaring nation. Like England, Spain and Portugal crossing the seas in search of their nations' greatness, so we reached for the skies and ennobled our nation."

Schirra retired from the Navy as a captain and from NASA in 1969 and became a commentator with CBS News. His enthusiasm and knowledge of the space program coupled with his charismatic on-the-air presence made him an even more widely known national and international figure.

He complemented CBS anchorman Walter Cronkite and the two became a powerful space-coverage team. Schirra worked for CBS from 1969 to 1975. He also engaged in a range of business activities and in 1979 formed his own consultant company, Schirra Enterprises.

Walter M. Schirra, Jr., was born in Hackensack, N.J., on March 12, 1923. He graduated from the U.S. Naval Academy in 1945, and from Naval Flight Training at Pensacola Naval Air Station, Fla., in 1947. After service as a carrier-based fighter pilot and operations officer, he attended the Naval Test Pilot School at Patuxent River, Md. During the Korean War he flew F-86 Sabres under an exchange program with the Air Force.

Schirra was chosen as one of the original "Mercury Seven" from among 110 selected test pilots from the Air Force, Navy and Marine Corps after exhaustive physical and psychological examinations.

Known for lively storytelling and practical jokes, one of his best-known anecdotes from astronaut training came when he and the others were continually being examined and subjected to demands for samples of body fluids. When one nurse insisted he provide a urine sample, Schirra reportedly filled a 5-gallon jug with warm water, detergent and iodine and left it on her desk.

"Levity makes life a lot easier," he once told a Houston reporter.

Griffin noted that "It was impossible to know Wally, even to meet him, without realizing at once that he was a man who relished the lighter side of life, the puns and jokes and pranks that can enliven a gathering. But this was a distraction from the true nature of the man. His record as a pioneering space pilot shows the real stuff of which he was made. We who have inherited today's space program will always be in his debt."

The Mercury Seven trained initially at NASA's Langley Research Center in Hampton, Va. In 1961 they moved to the newly established Manned Spacecraft Center (now the Lyndon B. Johnson Space Center) near Houston.

Schirra's Sigma 7 mission was called "the perfect flight" by space reporter and author Howard Benedict. After Schirra's splashdown near the carrier USS Kearsarge near Midway Island in the Pacific, he pronounced himself "healthy as a bear" and "happy as a lark."

Schirra's Gemini flight with Stafford was something of an improvisation. They had been scheduled to rendezvous in orbit with an unmanned Agena to be launched 90 minutes before the Gemini liftoff. But six minutes after the Atlas-Agena left the pad it exploded, and the Gemini 6-A launch was postponed.

Eventually it was decided to use Gemini 7 as a rendezvous target for Gemini 6-A. Both were to be launched from Pad 19 at Cape Canaveral, so a record turnaround of the launch pad was necessary. Working around the clock, crews got the pad ready in just eight days after the Gemini 7 liftoff.

The Gemini 6-A countdown reached zero on Dec. 12, 1965, and the rocket engines ignited - then shut down. The two astronauts had to wait almost half an hour atop the fueled rocket before getting out of the capsule. The problem turned out to be minor, the failure of an electrical connection.

Three days later, Gemini 6-A was launched without a hitch. The mission proved the spacecraft could be readily maneuvered. It was an encouraging development in the race to reach the moon.

By the launch of Apollo 7 in October 1968, the moon landing seemed to be coming within reach. The success of the flight proved that it was. Accomplishments of the mission commanded by Schirra resulted in the next flight, Apollo 8, being sent around the moon.

Apollo 7 had not been all smooth sailing. All three astronauts had colds. Schirra was occasionally firm in rejecting requests from the ground to insert additional events in the already-crowded flight plan.

"Television will be delayed, without any further discussion, until after the rendezvous" (with a spent rocket stage), he said. He subsequently was even more critical of efforts to add events to the flight plan. Eventually the almost daily television transmissions from Apollo 7 became popular mainstays of the mission coverage. Schirra subsequently apologized for the tone of some of his criticisms, though not for their content.

After leaving NASA, he participated in a number of television presentations and films, and served as national spokesman for several organizations and companies. He also held numerous directorships for a variety of businesses, in addition to his consulting work. He also wrote two books, "We Seven" published in 1960 and "Schirra's Space" published in 1988.

Schirra's military awards included the Navy Distinguished Service Medal, three Distinguished Flying Crosses, three Air Medals, two NASA Distinguished Service Medals, the NASA Exceptional Service Medal and the Philippines Legion of Honor.

He was awarded honorary doctorates by several institutions of higher learning.

He was active in a number of organizations. He was on the Advisory Committee of the Oceans Foundations, the Advisory Board/Council of U.S. National Parks, the Advisory Board of International "Up With People" and was a founding member and director of the Mercury Seven Foundation.

He also was a director of the San Diego Aerospace Museum, a trustee of the Scripps Aquarium, and a member of the International Council of the Salk Institute.

Schirra lived in Rancho Santa Fe, Calif. Survivors include his wife Josephine, his daughter Suzanne and son Walter Schirra III.

Images and video from Schirra's years with NASA can be seen at: http://www.nasa.gov/vision/space/features/walter_schirra.html