There are some pictures that will live with us forever.

President Kennedy's young son, John-John, saluting as his slain father's casket passes on its final journey to the Arlington Cemetery in 1963; U.S. Marines raising the flag at Iwo Jima's Mount Suribachi in March 1945; and the airship Hindenburg, crashing and burning in Lakehurst, N.J., on May 6, 1937.Pictures in time.

Today, unbelievable as it may sound for those who have seen the horrific pictures of the Hindenburg or to those old enough to have actually lived it, the time of the giant airships may have come again.

More than a century after Count Ferdinand von Zeppelin launched his first flight, airships are being viewed as an inexpensive, environmentally friendly way to haul freight across Europe.

A German company announced in December it will start producing 300 giant airships this year at a former Soviet military air base near Berlin. Cargolifter, as it will be known, is designed to carry up to 160 tons of freight, far more than the biggest aircraft.

''Heavy machinery and vehicles can be transported quite easily by sea, but the problems start once you get to the harbor. Roads are overcrowded, so trucks often face long delays. And the public is increasingly concerned about the effect transportation has on the environment,'' said Carl von Gablenz, chairman of Cargolifter AG.

Zeppelin built more than 100 airships in Germany during the early part of this century, and they were used by both sides in World War I.

The era of the airship came to an abrupt end in 1937, when Zeppelin's giant ship, the Hindenburg, burned as it was landing near Lakehurst.

''Ever since, most people have regarded the airship as unsafe. But the reason the Hindenburg exploded was that they didn't use enough helium. Now there is no shortage, and that danger is gone,'' notes Mr. von Galenz.

Airships use helium, a gas lighter than air, to rise above the ground. One cubic meter of incombustible helium will carry 1 kilo of weight without being consumed, making airships much less energy-hungry than aircraft, which burn 1 kilo of fuel for every kilo of payload trans- ported.

The Cargolifter will be 800 feet long and travel at up to 87 miles an hour. Because it will avoid traffic jams and airport de- lays, it will still be faster than other means of transporting very heavy goods.

Mr. von Gablenz sees a big mar- ket for the airship in inaccessible and difficult terrain because, un- like an aircraft, it does not need to land before it unloads its cargo.

''It hovers above the ground, like a floating crane. We have developed technology which makes it possible to lower the freight into an exact place, within a centimeter of precision,'' he said.

The public may welcome the environmentally friendly side of the Cargolifter, but some may feel uncomfortable about such heavy loads hovering above them.

Mr. von Gablenz insists there is nothing to fear because the cargo will be fixed to the spine of the airship and will not hang below: ''Besides, if a Boeing 747 is taking off, the fuel alone weighs 130 tons, but nobody worries about that falling out of the sky.''

The company plans to build a prototype this year, and the first fully functional Cargolifter should take to the skies in 2000.

A consortium including Siemens, Thyssen and 20 transport companies has pledged $67 million to start building, and Mr. von Gablenz envisages an international network of airship services in which Britain would play an important role.

The worldwide shortage of airship pilots means Cargolifter AG will have to train its own 12-strong crews for each craft and will run the first services itself.

Nevertheless, Mr. von Gablenz is confident that, despite the difficulties, the cigar-shaped curiosities are set for a successful comeback and will soon be a familiar sight.

''The airship is coming back at a time when it doesn't have to compete with other forms of transportation, because they are reaching the limits of their usefulness,'' he says.