Fog* 4THE STARS AND STRIFES14 Plane* Shot Down in 100 Firings'■ '- ■-ur ‘ 1 ■ 1 ii jU.S. Jets Winning Against MissilesSaigon, April a? (AP)-The war In Viet Nam Is the first In which airmen are flying against ground-based missiles, Hie fliers Jn this case are American and the missiles arc made by the Soviet Union.The Americans claim they are winning out against the once-feared surface-to-air missile* made by the Soviet Union and supplied to the North Vietnamese forces,THEY ARE FIRED — possibly with the help of Soviet technicians and Inst roc tors — from launching sites clustered around the capital of Hanoi, the port city of Haiphong and elsewhere in North Viet Nam,To date, 14 American planes have been shot down by missiles since Feb. 7 of last year whenthe United Slate* began bomb* ing missions against the North.American officers regard this as a relatively small rate of loss when compared with the thousands of sorties flown In that period.Also, they regard the losses light when compared with the record of more than 100 firings of the missiles which are intended lo bring down a plane every time they are fired.Intelligence reports indicate lhat there are 25 to 30 active sites in North Viet Nam from which missiles are fired. The Communists arc believed to have about as many more prepared launching site* into which they can move the mobile missiles systems when needed.’‘It's like having a lot of empty foxholes and putting shooting soldiers In them when you wantthem,1* one American officer said.When this thing started over a year ago/' he continued, our pilots were apprehensive. Just imagine you are a fighter pilot and everyone tell* you that the missiles will knock you out of the sky the first time up.“But our fliers took the challenge and wc think we're beating it. Our countermeasures have been extremely effective.*'FART OF TIIE SUCCESS, U.S. offircrs sny. is that the Soviet missile* were designed primarily to shoot down high-altitude bomber* such ax Ibe B52, hut Utui they now are being used against fighters.Of Ihe countermeasure* against the missiles, one main method is evasive maneuvering by American jots. On one day last week, U.S. Air Force pilots evaded five missiles while flying over North Viet j Nam on missions to knock out installations.The other main measure is lo jam the radar systems used by ,Ihe Communists to detect attacking American planes and ,linked to the missile and other antiaircraft weapons, .To accomplish this Jamming, ,the U.S. Air Force disclosed this week It Is using the twin-jct }RB66, a recoimuissancc bomber converted into a plane loaded \with electronic devices, ,Manned by a crew of three, j(he RBfifl will lead n formation .of F105 TbtiwJercbiefs or F4C Phantoms across the 17th Parallel and jam the enemy radar while the flghtcr-bombers dive 1against their targets. \