Show AEROPLANE MOTORS VERY SHORT LIVED Correspondence Associated Press PARIS PAlIS Doc Dec Dee 20 The Tho Tho life of ot aeroplane motors In use uee ute Is not over oyer 50 hours and ad to assure asuro this much of ot them they must be taken apart cleaned and remounted every fifty hours according to the tha ex experIence experience ex- ex of ot French aviators since tho the war began As s the tho thel cost l of or one ono of or the motors motor W when hon h ordered by tho the hundred Is francs each the tho expense Is la a heavy y one ono One factory near Paris Is delVern delivering new aeroplane motors a month It I Is difficult to know details of or the aeroplane work but It Is assumed that from lye fl to ten aeroplanes nes RO go 10 out of oC ao 00 lion ton each Cach di da day disabled by hostile hostilo fIre tro or orby orby by wear and tear The Tho military mitar aviation schools are training train train- Ins InS' many man hundreds of or young oun aviators BO so that there thero Is I a co constant renewal of ot the human material at tho the front and a steady chines In Increase acton action In tho the number of ot air all machInes machines ma ma- mo |