SEATTLE (AP) _ More than half the Navy's A-6E Intruder jets - bombers designed to attack from low altitude - have been grounded or restricted from flying stressful maneuvers because of age, a newspaper reported Wednesday.

The two-man A6-E, with terrain-hugging and all-weather electronics, is the only Navy bomber that can attack at night and in bad weather.

But fliers say the dangerous duty is being made even riskier by aging aircraft and a shortage of planes, the Seattle Post-Intelligencer said.

The Navy has flown the A-6E since 1972, but budget cuts in 1987 and 1988 mean the aging fleet of A-6Es will be forced to fly 10 to 20 years more until the carrier-based A-12 ''stealth'' bomber is fully operational, officers said.

The Seattle Post-Intelligencer said that of the 289 A-6Es, 52 are grounded because they are beyond the 2,200-hour life of the wing, and 120 that are approaching the 2,200-hour limit have been restricted to three ''Gs'' of gravity in flight. The Navy estimates eight more A-6Es will be grounded this year.

G-forces are a measure of the stress on a body during rapid acceleration; excessive G-forces can tear off a jet's wings. During combat, an A-6E experiences 6 to 6 1/2 G's, said Dur Roberson, a retired Navy A-6 pilot.

An A-6E restricedto three 3 G's could do all of its usual maneuvers but would require more space, he said.

Many squadrons must take ''G-restricted'' Intruders on six-month carrier cruises because there are not enough fully capable A-6Es, the newspaper quoted Navy sources as saying.

In 1987, nine training accidents made the A-6E the Navy's most dangerous aircraft. In April and May of last year, four men died when two A-6Es crashed near Mount St. Helens while on training runs. The accidents were the only two in the Navy in 1988, giving the service its lowest crash rate in 11 years.

A congressional review deemed the 1988 crashes ''an aberration and not a trend upward in A-6E accident experience.'' The causes of the accidents have not been disclosed.

The Post-Intelligencer said interviews and Navy documents, some obtained under the Freedom of Information Act, showed that crew error was the leading cause of more than half the 62 Intruder crashes in the past decade.

Other crashes have been linked to the A-6E's age or to deficiencies that new equipment could correct, but exact numbers are classified, the Navy said. On Jan. 14, 1987, the wing on a Whidbey A-6E collapsed from metal fatigue during a training flight in California, killing the instructor-pilot.

Recent deaths prompted the Navy to redesign the ejection system on the two- seat A-6Es. The plane was the only multiseat Navy aircraft that lacked a ''command ejection'' system allowing one crewman to eject the other.

Senior Navy officials defend both the A-6E and the service's training but don't conceal anxiety over the deterioration of the A-6E fleet.

''Anytime you put 3-G restrictions on an airplane, the obvious answer is that you are starting to affect your operations,'' warned Rear Adm. Grady L. Jackson, wing commander at Washington's Whidbey Island Naval Air Station.

Whidbey is the Pacific Fleet base for A-6Es; the Atlantic Fleet base is Oceana Naval Air Station at Virginia Beach, Va.

''The common thread that we find (in recent crashes) and that we're working on all of the time is that the mission of the A-6 is the hardest mission that any Navy airplane has to do,'' said Rear Adm. Fredrick Metz, who commanded the Whidbey air wing until Aug. 1. ''We train in conditions of adverse weather. ... We've had them (accidents) in the most adverse conditions that we can possibly fly in.''

The Navy has contracted with Boeing Military Airplanes to build new composite-material wings for the grounded bombers. But the program has suffered delays since 1987. The Navy was forced in 1988 to go to Grumman Corp., the A-6E manufacturer, for 10 metal wings in the meantime, said Lt. Janet Mescas, a Navy spokeswoman.