Among the wide array of Vietnam War movies that we've seen in the past 20 years, there haven't been many comedies. Much less family comedies.

But here comes "Operation Dumbo Drop," based (no doubt quite loosely) on a true story about American soldiers in 1968 transporting an elephant some 200 miles through the jungles of Vietnam to a small Montagnard village.

The village is being used by easygoing Capt. Cahill (Danny Glover) as a strategic outpost for keeping tabs on activity along the Ho Chi Min Trail, which is used by the Viet Cong to transport weapons.

But when the enemy discovers that villagers are cooperating with Americans, they shoot and kill their elephant, an animal that is both a tool for farming and a creature of worship.

So, Capt. Cahill, whose tour of duty is almost up, forms an uneasy alliance with uptight, hotshot West Point graduate Capt. Doyle (Ray Liotta), who is taking over.

To aid in their effort, they recruit a pair of young soldiers, superstitious H.A. (Doug E. Doug), who is scheduled to head home in seven days, and klutzy Iowa farm boy Lawrence Farley (Corin Nemec). They also blackmail a supply officer, a hustler named Lt. Poole (Denis Leary), into helping.

After negotiating for an elephant (who is accompanied by a young orphan boy as a part of the deal) they take the beast by plane, by truck, by boat and then by parachute over the mountains and through the jungle, dodging enemy fire all along the way.

Glover and Liotta play against each other pretty well, though there is none of the chemistry Glover has with Mel Gibson in the "Lethal Weapon" films. And Nemec, as the slightly goofy rube who seems lost in the woods, and young Dinh Thien Le as the boy who comes with the elephant, have their charm. But it is Doug and Leary who garner the laughs here, popping off one-liners and asides that sound suspiciously like ad-libs.

Director Simon Wincer ("Free Willy," the TV miniseries "Lonesome Dove") moves things along quite well, and there is some impressive stunt work (though Wincer is unquestionably better with action than slapstick).

But the screenplay by Gene Quintano ("National Lampoon's Loaded Weapon 1") is strictly by-the-numbers stuff and contains some wildly implausible elements. (One wonders if he watched Tony Curtis in "Operation Petticoat" as inspiration for Leary's character and perhaps Charlie Sheen in "Terminal Velocity" while developing the climactic parachuting-elephant sequence.)

Two questions nag at me, however: How much do you suppose Nestle paid for the blatant candy bar product-placement? And is Leary serious or joking when he says, "I'm in an episode of `McHale's Navy' "?

"Operation Dumbo Drop" is rated PG for violence and vulgarity.