MEC 3766Instrumentation and AvionicsAvionicsTerrestrial Landing Aids2INSTRUMENT LANDING SYSTEM (ILS) assists pilot in positioning the aircraft for laning !ner lo" visi#ilit$ conitions s!ch as fog% sno"% lo" clo!s% rain an ar&ness' li&e ()R% ILS !ses (*+ fre,!encies an irectional antennas'T"o trans-itter of (*+ are locate at the r!n"a$'. Locali/er0 provie for a/i-!th infor-ation (123 M*/4115 M*/)' . Glie slope 0 provie for elevation infor-ation (653 M*/4667 M*/)'provies infor-ation a#o!t 0 . a/i-!th reference . appro8i-ate range . elevation reference3INSTRUMENT LANDING SYSTEM (ILS)150 Hz 0 HzLocalizer Raiates t"o lo#es% one is -o!late at 92 */% an other is -o!late at 1:2 */'The t"o lo#es overlap at e,!al strength along the centerline of the r!n"a$% an create a /one of overlap in the center'INSTRUMENT LANDING SYSTEM (ILS)!se o" Localizer Locali/er inicator Glie slope;o!rse Deviation Inicator "ith Locali/er an Glie slope eviation #ars150 Hz 0 Hz5INSTRUMENT LANDING SYSTEM (ILS)!se o" Localizer Locali/er inicator Glie slope+l$ right+l$ leftIeal +l$ !p?aircraft #elo" glie path>+l$ o"n?aircraft a#ove glie path8INSTRUMENT LANDING SYSTEM (ILS)Mar%er &eacons The istance infor-ation is given to the approaching aircraft fro- gro!n antennas a#o!t 7 NM fro- the en of the r!n"a$' )!ter -ar&er (@22 */)' (Al!e color% 5 ash #eep per secon)Mile -ar&er% 1'1&- fro- r!n"a$ (1622 */)' (A-#er color% ot an ash)Inner -ar&er% 2'6&- fro- r!n"a$ (6222 */)' (Bhite color% 7 ots per secon)r!n"a$Mile -ar&er )!ter -ar&erC'5 &-1'1 &-inner -ar&er2'6 &-910MI;R)BA(E LANDING SYSTEM (MLS)o Micro"ave Laning S$ste- (MLS) has #een aopte #$ I;A) as the stanar precision approach s$ste- to replace ILS'o MLS provies precision navigation g!iance for align-ent an escent of aircraft on approach to a laning #$ proviing a/i-!th% elevation an istanceT"o h!nre channels are availa#le #et"een :261 an :292'7 M*/'ML' (!)CTI*)'1' Approach a/i-!th5' Aac& a/i-!th6' Approach elevation@' Range:' Data co--!nications 11MI;R)BA(E LANDING SYSTEM (MLS) single approach path site sensitivit$ an high installation costs -!lti path interference channel li-itations . @2 channels onl$IL' LIMITATI*)'12MI;R)BA(E LANDING SYSTEM (MLS)ML' A+,A)TA#E'1'eli-ination of ILSD+M #roacast interference pro#le-s5'provision of all."eather coverage !p to E72 egrees fro- r!n"a$ centerline% fro- 2'9 egree to 1: egrees in elevation% an o!t of 52 na!tical -iles (NM) 6'capa#ilit$ to provie precision g!iance to s-all laning areas s!ch as roof.top heliports @'contin!o!s availa#ilit$ of a "ie range of glie paths to acco--oate ST)L an (T)L aircraft an helicopters :'acco--oation of #oth seg-ents an c!rve approaches 7'availa#ilit$ of 522 channels . Fve ti-es -ore than ILS C'i-prove g!iance ,!alit$ "ith fe"er a>le2 2long latd d R + =