at Aviano Air Base, Italy - The fighter jets flying day strikes over Yugoslavia are just returning to Aviano, and it's time for Jeremy Tygrett to put on his bunny suit. After the push crew has wheeled the F-16 onto a maintenance pod and the pilot has dismounted the plane, the technician from South Carolina climbs into the blowsy khaki jumpsuit. He pulls its soft hood over his head and up to his chin and dons hospital-like latex gloves and rubbery overshoes. The job at hand is surgical indeed: Senior Airman Tygrett, 22, will climb down the F-16's intake manifold just beneath the cockpit, and, with the same touch a blind man uses with Braille lettering, he will read the guts of the plane with his fingertips. The six-footer disappears completely into the belly of the plane. If he detects even the slightest prick, especially when probing the razor edge of the F-16's turbofan engine, then this plane will be down for a few hours while engine specialists comb it for debris. Even a pebble sucked into the delicate clockwork of this $20 million aircraft can pose real danger on the ground or, worse, in the skies over Kosovo. If all goes well (which it does), Senior Airman Tygrett and other maintenance workers will have the F-16 ready to fly again in just over an hour. Up and down the flight line, others repeat the same procedures. Technicians check and recheck engines, download computer readings of the mission just completed, gauge tire pressure, flag with loops of red tape unexpended bombs or missiles so that ammo workers are sure to inspect them before the next flight, and sweep errant cracker crumbs or candy bar wrappers from cockpits. These are the daily duties of an air war, and the young men and women who perform them are the least noticed of its sublime combatants. At Aviano, a busy strip at the base of the Alps in northern Italy, it is Day 56 of NATO airstrikes against Yugoslavia. But it hardly matters what day it is; they're all known here as Groundhog Day. In order to carry out NATO-appointed air strikes, both pilots and support crews are working 12-hour shifts with maybe one day off in seven. Like the Bill Murray character in the movie Groundhog Day, the air crews fight the tyranny of the mundane in the face of each day's routine. The diplomats in Belgrade or Bonn may be on-again, off-again with what may or may not prove to be lasting peace, but for the folks on the ground, success is measured by doing the same thing, the same way, over and over. "The only way we know it is the weekend around here is when somebody gets on the Internet to check the stock market, and the stock market is closed," says pilot Alex Calicchio. In two months of fighting Slobodan Milosevic's Yugoslavia, NATO forces have averaged flying 600 sorties a day in and out of Serb territory. From up and down the Adriatic coast of Italy, as well as from bases in Spain, Germany, and Hungary, U.S. fighter pilots fly 'round the clock in order to keep up the pace. They leave Aviano in "strike packages," usually four jets dedicated to bombing runs, with two to four more protecting the strikers from Serb artillery in what is called SEADs, or suppression of enemy air defenses. Additional support comes from AWACS reconnaissance planes and Stealth bombers. Capt. Calicchio, who flies SEADs in an F-16/CJ equipped to intercept Serb surface-to-air missiles, takes off at sunrise. A typical sortie, with targets now concentrated farther to the south in Kosovo, will last six hours. His job, he says, is "to make sure our guys don't get shot down." With regularity, he and other pilots attest, Serbs on the ground fire upon the crews. After an initial bombing run, his team will refuel mid-air and then hit targets again before returning to the base. By the time he deplanes, unsuits, reviews a videotape of the mission, and passes the data off to intelligence officers, he will have been on the job for 12 hours. That leaves just enough time to get the required minimum rest-12 hours-before flying again. NATO officials in Brussels say more than three-quarters of Mr. Milosevic's surface-to-air defenses have been destroyed. That still leaves something to worry about, according to Capt. Calicchio. "They are still active. Sometimes it's like the ground opened up and they are angry. It's not like you can think of this as a peacetime mission. They still have the capability to hurt us," he says. The terrain and tighter quarters above Kosovo also make it more difficult to circumnavigate trouble when it erupts, pilot Clyde Bellinger told WORLD. A 17-year veteran who flew in Desert Storm, he said the mission itself was more clear-cut then. "When we went into Desert Storm initially, there were formal objectives and we knew exactly what had to take place for the campaign to be over. With the NATO alliance there are established objectives, but it is more difficult with Milosevic how to assess whether we meet those objectives. That can be frustrating." Frustrations-and risks-grow as the mission stretches into the summer with no end-game scenario in place. On May 28, an Air Force A-10 attack jet just barely escaped Serb anti-aircraft fire. It pulled out of the mission and made its way safely back to Italy. Aviano boasts the highest number of aircraft dedicated to the war effort. With 135 U.S. planes, plus air forces from Canada, Great Britain, and other NATO countries, the base puts up the largest daily show of force over Yugoslavia, under the command of Air Force Brigadier General Dan Leaf. Airstrikes during daylight hours began around Day 40 of the war. Day packages head out shortly after lunch and return at sunset. Night packages take off shortly after midnight and are expected back by dawn. The tempo creates a near-constant scream and rumble of jets pulling 9 Gs. Those who remain on the ground are fighting their own gravity, keeping to the extra-long workday and making sure the planes are ready to fly on demand. "You could not have a life if you did this back home," says Capt. Calicchio, a Chicago native who was deployed to Aviano from Shaw Air Force Base, S.C. The even bigger contrast from training in the United States, however, "is people are dying. You'd be a fool not to at least think about that when you go home for the day." Much as the airmen try to stick to the purely tactical, diplomacy and politics have a way of intruding. On Day 56 a busload of Russian military experts makes a surprise visit to Aviano, something that is apparently technically acceptable under terms of the Conventional Forces in Europe Treaty. The post-Cold War agreement caps the number of tanks, armored combat vehicles, heavy artillery, combat aircraft, and attack helicopters that NATO and the now-defunct Warsaw Pact may hold between the Atlantic Ocean and the Ural Mountains. Maintenance workers pluck gravel from the tire treads of the bus-a precaution for the jets the Russians are riding onto the tarmac to see. The bus stops in front of one of the hardened hangars housing a Stealth fighter. Capt. Edward Thomas, Aviano's spokesman, says the Russians have picked "an inopportune time" for a tour; but with Russian Foreign Minister Victor Chernomyrdin shuttling between NATO capitals and Belgrade trying to stop the war, the Russian team might be thinking differently. Aviano's commander, Dan Leaf, waves away discussion of the Russians. He has already met with the delegation, agreed to the visit (while restricting its scope), and is back to the more pressing details of running a swelling multinational command in combat mode. For Gen. Leaf, Day 56 comes 25 years to the day since his commissioning as an Air Force pilot. Since last November, when he took over the 31st Fighter Wing at Aviano, the number of airmen under his command has ballooned until he now heads the largest expeditionary force of fighter pilots in U.S. Air Force history. Keeping on top of it requires keeping a military-issue cot in the corner of his office. It looks recently rumpled. He says it got more use during the early days of the war, but admits, "I'm a big power nap kind of guy." Despite thousands of hours in both the F-15 and F-16 cockpit and duty patrolling the no-fly zones over Bosnia and Iraq, Gen. Leaf had never flown a combat mission-"where they shoot back at you"-until Kosovo. Now he flies them 2-3 times per week. "I go in as lead or on the wing, your basic strike man," he said. "I am a plain old pilot." Why put a commander in harm's way? "First, you cannot lead a tactical unit in combat if you are not going in yourself. You cannot say, 'Hey, have a nice day, and let me know how it works out.' Second, it lets me see firsthand if there is the need to fine-tune and adjust. You cannot know how it is going unless you have rejoined the tanker at night, in bad weather, on night-vision goggles, in a big strike package, and worked the coordination with AWACS. You have to see it." Besides taking care of the troops, which for Gen. Leaf is job No. 1, he is NATO's point man for accomplishing the tactical side of the Kosovo campaign. Others select targets. Gen. Leaf is supposed to make sure they get blown up. "Our mission has been pretty well set by NATO from a military and strategic sense. From a personal sense, having seen the tragedy in Kosovo from the air and watched the houses burn, one goal is immediate-put an end to that and allow the Kosovar Albanians to return and establish some sort of normalcy-fix what Milosevic has done. From a personal moral perspective, I would like to make sure that ethnic cleansing is not the standard in the next century. I'd like to make sure that it is not an acceptable way of doing business in our world," he says. Steering past the controversial political issues of the air campaign is one way to get the commander's job done. But controversy won't leave Gen. Leaf entirely alone. His NATO superiors shield him from the press-his interview with WORLD was only his third since the air war began March 24-but they flew him to Brussels for a press briefing April 22 after fighter jets based at Aviano blew up a convoy that reportedly killed over 80 refugees. The brigadier general is convinced Mr. Milosevic created that tragedy, by placing civilians within a bona fide military target. But the incident illustrated an Air Force tenet: Air wars are not antiseptic. "There is nothing sterile about taking an aircraft over enemy territory and being shot at," says Gen. Leaf. "If you watch the video, it looks all mechanical, but it is not. It is hard physical labor. It is demanding. This is not a situation where you just sling your bombs wherever you want. We make difficult tactical decisions to make sure we don't put civilians at risk." In the end, assuming risks are successfully managed, can anyone really believe Mr. Milosevic will surrender to an aircraft? A growing number of politicians and military experts say no. Even NATO has increased its authorized ground troop strength to 50,000. President Clinton and the Pentagon flinch from the option. Support within the U.S. military, at least in the Air Force, is there. Air Force brass grow weary of putting their airmen out every day over Kosovo, while the Army's Apache helicopters sit idle in nearby Albania. The imbalance is particularly hard to take, considering that four-star Army Gen. Wesley Clark is in charge of the NATO operation. One source told The New York Times that the real concern of Army officers at the Pentagon is to avoid being drawn into the fighting. "It does appear that the Air Force is prepared to accept more risk than the Army," the source said. Another told WORLD, "The Air Force is out front hitting the targets NATO says to hit, but the targets are not costing Milosevic. We are not hitting his center of gravity. Bombing Kosovo does not get at his power base." Gen. Leaf acknowledges that the training scenarios his airmen have drilled included ground forces. "But you cannot simulate the politics. Politics are the reality. Folks tend to look at that as a constraint, but it is also an enabler," he says. He believes, "It is unimportant what is decisive. It doesn't matter if it is air power, ground power, or-ideally-diplomatic power. The only measure is Milosevic relenting. How many tanks we have hit, how many surface-to-air missiles, how many airplanes, is unimportant until we stop that." Military expert Craig Nation, professor of military studies at the U.S. Army War College, disagrees. He told WORLD, "We say we are seeking Milosevic's 'breaking point,' but this leaves it up to him to decide when or when not to 'break.'" With the night strike crews beginning to take off, Gen. Leaf turns diplomatic about his military mission. "We are fighting the tactical war here. We have to win the tactical battles and stay focused on that," he says. "When I rock my grandchildren on my knee, I will probably ponder on what may have been options or not options, but right now I am focused on winning the tactical battle every day." In a combat zone, the brave face of doing well is the only one to wear.