AS the C-130 military transport plane makes its final approach to Sarajevo, the devastation wrought by war does not come into focus until the plane hits about 1,500 feet.
Above that level, the scars from two years of internecine combat - pockmarks in walls, blown-out windows, gutted buildings - are hard to detect. Deep-blue lakes and clusters of white houses with red-tiled roofs, nestled among the mountains of Bosnia-Herzegovina, seem only to glisten in the spring sunshine. The scene gives an impression of stability, even tranquility.
But as the plane descends toward the Bosnian capital, offering a better look at the ground, any air of normality quickly dissipates. The need for humanitarian aid deliveries becomes clear.
About a mile or so from the runway, two white objects sitting on a hill suddenly become recognizable as tanks, the blue ``UN'' markings clearly visible as the plane passes overhead.
Then, the C-130 whizzes past the bombed-out skeletons of apartment blocks in Sarajevo's outskirts to the left. Touching down, the plane zips past a hastily dug cemetery bordering the runway on the right.
``It's sad to see such a beautiful city completely destroyed. I don't think I'll ever understand what caused it to happen,'' says Capt. Kevin Samuel, the navigator.
Captain Samuel may not comprehend the forces at work in the Balkans, but that has not prevented him from logging lots of flight time trying to help those who have suffered the most in the Bosnian war: the noncombatants.
Dozens of American, German, and French aircrews, operating under United Nations auspices, have ferried supplies to Sarajevo since July 3, 1992. In addition, they have air-dropped humanitarian aid for the past year to those civilians caught in isolated Bosnian government strongholds surrounded by Bosnian Serb forces, who have hindered overland deliveries.
United States and UN officials say the aid effort, known as Operation Provide Promise, has made the difference between subsistence and starvation for tens of thousands of people.
``Some of these enclaves simply wouldn't have survived,'' US peace negotiator Charles Redman said, speaking to the Monitor as he flew into Sarajevo recently.
And, until the mostly Muslim residents of Sarajevo - along with those in so-called ``safe havens'' scattered throughout Bosnia - are able to feed themselves, the UN aid effort will continue, officials say.
``I never expected it to go on this long,'' says Brig. Gen. Donald Loranger, commander of the 435th Tactical Airlift Wing based at Rhein-Main Air Base, near Frankfurt, Germany. ``We're prepared to go on pretty much indefinitely.''
In the aftermath of NATO bombing raids against Serb forces surrounding Gorazde in eastern Bosnia, the UN temporarily suspended aid flights into Sarajevo on April 10. Tension is rising there, as Bosnian Serb forces in recent days have renewed their blockade of the Bosnian government-controlled portion of the city. Nevertheless, US officials said they planned to resume the Sarajevo airlift over the weekend.
So far, the airlift has delivered more than 42,720 tons of food and supplies to Sarajevo, and dropped another 17,560 tons over besieged Bosnian Muslim enclaves, such as Gorazde, Maglaj, and Zepa. The operation involves more than 1,000 people, based at Frankfurt's Rhein-Main base.
The US aircrews are made up of both active duty and National Guard personnel. Captain Samuel's crew, for example, was drawn mostly from West Virginia's Air National Guard, serving a month-long tour of duty.
A typical Sarajevo delivery mission lasts 12 hours, with up to four C-130s per day departing Rhein-Main in the early morning. After landing in Sarajevo, the planes fly to one of two Croatian cities - Split or Zagreb - where the UN has aid resupply depots. Then, it's back to the Bosnian capital. In all, the transport planes deliver up to three loads of cargo per day before returning to Rhein-Main.
The airdrop missions involve up to six C-130s and last about seven hours, flying at night to minimize the risk of being fired on.
``This is an environment where we have to use weather, darkness, and moonlight ... to keep ourselves in one piece,'' General Loranger says.
So far, no C-130 on an airdrop mission has been hit by hostile fire, but that does not mean fighters on the ground aren't trying, the general adds. The threat has increased of late, as the Gorazde raids have prompted Serb military leaders to threaten to shoot at NATO planes flying over Bosnia, using shoulder-mounted surface-to-air missile launchers.
Already the groundfire threat has forced the US, German, and French aircrews to develop new techniques for high-altitude airdrops. In the past, C-130s usually dropped loads while flying at under 1,000 feet. But over Bosnia, the humanitarian bundles are falling out of the planes at altitudes above 10,000 feet.
One innovation disperses individually wrapped meals in mid-air. That means huge bundles of aid will not come crashing down on buildings, or fall into the hands of combatants and black marketeers, thus enhancing the chances for besieged civilians to receive a fair share of food.
The airdrops have been criticized for being inaccurate, doing more to feed the warring factions than the suffering civilians. But US and UN officials maintain the airdrop missions have a 90 percent success rate.
``It's easy to accuse us,'' Sadako Ogata, the UN high commissioner for refugees, said at a recent Frankfurt news conference. ``At the same time, I am happy to realize that after the two winters that we had there, there has been no mass starvation.''
Even during the relative quiet of the last two months in Sarajevo, the airlift operation has always remained on a war footing.
As a security precaution, landings at the city's battered airport have been staggered so that only one plane is supposedly on the ground at any given time. The airport itself is under a siege mentality, comparable to the image of Khe Sanh, the American base that held out against a North Vietnamese encirclement during the Vietnam War.
A series of sandbagged trenches and bunkers are dug in the earthen strip between the airport's runway and taxiway. The terminal buildings, meanwhile, are protected by high earthen ramparts and more sandbags.
The US C-130 airmen communicate with French ground crew members - who are dressed in full battle gear, including flak jackets - mostly in an improvised sign-language. They waste no time hustling cargo off the plane, which keeps at least one engine running at all times in case a quick getaway is required.
``Back in January, a plane on the ground would take a round now and then,'' notes Lt. Paul Gardner, the C-130's pilot. ``They [Bosnian Serb forces] were lobbing a lot of mortar shells at the airport.''
No one is ready to predict when the aid mission will cease and a lasting peace will come to Bosnia. ``People are really taking to peace,'' said Mr. Redman, the US negotiator. ``The politicians [in Bosnia] are not as easy to convince.''
After a long day, Lieutenant Gardner guides the C-130 back to Rhein-Main. When the skyscrapers of Frankfurt come into view in the distance, rising through the hazy twilight, a sense of accomplishment fills the cockpit.
``It may get a little monotonous at times. But the bottom line is we're doing some good. This is the most satisfying kind of mission,'' said Captain Samuel. ``I'd like to get back for another tour.''