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STUDENT REPORT COMING SOON TO A THEATER NEAR YOU.

THE MICROWAVE LANDING SYSTEM

MAJOR KELLY S.C. HAMILTON 83 102^ — 'insights into tomorrow"

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DISCLAIMi-R

The views and conclusions expressed in this document are those of the author. They are not intended and should not be thought to represent official ideas, attitudes, or policies of any agency of the United States Covernmorit. The author has not had special access to official information or ideas and has employed only open-source material available to any writer on this subject.

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REPORT NUMBER 85-1025

TITLE C0N1NG S00N T0 A THEATER NEAR YOU..., THE MICROWAVi: LANDING 5Y5TEM.

AUTHOR(S) MAJOR KELLY 5. C. HAMILTON, USAF

FACULTY ADVISOR MAJOR IRVING F ROMER, ACSC/EDOWB

SPONSOR MAJ0R J0HN PLANTIK0W' SIFC/CC, CASTLE AFB, CA

Submitted to the faculty in partial fulfillment of requirements for graduation.

AIR COMMAND AND STAFF COLLEGE AIR UNIVERSITY

MAXWELL AFB, AL 36112

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._MCLASSIFIF.a SECURITY CLASSIFICATION Of- 1 HIS PAGE

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REPORT DOCUMENTATION PAGE Is REPOHl SCCUrtlTY CLAaUK K.Al ION

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COMING SOON TO A THEATER NEAR YOU....THE

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12. PERSONAL AUTHOFMS)

Jamilton, Kelly S.C., Major, USAF "3b. TIME COVERED 13a. TYPE OF REPORT

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1985 April 15. PAGE COUNT

22 1«. SUPPl 6MF.NTAP1V MOT/- CION

ITEM 11. MICROWAVE LANDING SYSTEM

17 COSATI CODER

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IÜ. SUBJECT TE FIMS tContinue on reverse if necessary and identify by bloch number)

19. ASSTUACT iCvntinue on ivt/cfae if necenaarv and identify by block number)

Handbook designed to familiarize aircrew members with new Microwave Landing System. Hand- book provides a comparison of Instrument Landing System (ILS) and Microwave Landing System (MIS); a discussion of ICAO standards for the new MLS, actual system specifications, and a short introriur-tion to future uses of MLS, specifically the development of the Joint Tact i t a I Microwü >/e I.anding Sys Lein.

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UNCLASSIFIED/UNLIMITED tj SAiviil AS BPT B OTIC USERS D

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ACSC/EDCC Maxwell AFB, Al 36112

DO FORM "1473, 83 APR

21. ABSTRACT SECURITY CLASSIFICATION

UNCLASSIFIED 22b TELEPHONE NUMBER 22c OFFICE SYMBOL

EDITION OF 1 JAN 73 IS OBSOLETE UNCLASSIFIED SECURITY CLASSIFICATION OF THIS PAGE

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PREFACE

This informational Handbook has been prepared in response to a requirement levied by the SAC instrument Flight Course (SIFC), Castle AFB California fne Microwave Landing System (MLS) is projected for worldwide installation and use by both civilian and military facilities This handbook has been developed for use in conjunction with an individualized lesson plan, prepared by the SIFC faculty. 4-have attempted to layout The history, development, advantages, and future projections for this excellent system. *.-

The handbook is not a text for engineers, but for the pilot who is interested in safety of flight, no'se abatement, and increased system confidence I Wy- intent in authoring this project was to provide a brief introduction to the ••easons behind the transition from Instrument Landing System (US) to trie Microwave Landing System (MLS), and the international scope of this endeavor Through the comparison of the operational and maintenance advantages of these two systens/j hope:to capture the interest of pilots by raking them aware of the tremendous technological gains embodied m the Microwave Landing System.

Accession For

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ABOUT THE AUTHOR Major t<etty S.C Hamttton, a 1973 graduate> of- OHic~r Training :.chool. dtlendeod Av10mcs Maintenance OHicer Course. Lowry AF8. Colorado. 1n1 ally d~signed to Nellis AFB, Nevada specializing in· mtegrated av1onics 5-y-::.ten~s.

she wcrked test stations for the ~-Ill. In !974, sne became respon::.iole ror ttle operat ione!l testing and evaluations of communi cat ions, navigat ton. <)nll electronic countermeasures syst~s for T-38, A-7, A-!0, F-4C. F-~ . ;;-•os, ana f-Ill tacttcal aircraft. She was awarded the Meritorious Service t·leaal for her co~t,..ibuttons to the technical deovelopment of Electrontc Counterrnf:la•.:.ures <ECM) and Counter-countermeasures (ECCM) for the origmal Project Red Flag war scer.ar io Her experience includes serving as avionics maintendnn• project off1rer for . operational test and ttValu~tien or tt1e AtM-9 mtss : l~. r.ne AL0-119 f(t1 pod, the APN-1 18 f ACAN system, and the ARC- t64 UHf r Jt1io. ~~t·,e

Wl5 a·lso •h£> av10ntcs consultant for F-5 forei<J!' mi,lttary sal~s progra.-n5, ~'nl1

tht' nrst operational testing of tne AWACS She was personally resr1ons1nle tor tec'n'cal changes to the F -s avton1c~ systt'ms. and traveled with n ~ F -5£ ··Aggressors· in support of Dissimilar Air Combat Trammg <DACT>.

A graduate of Undergraduate Pt lot Traintng (UPT • in 1978, she served as d

KC -135 co-p i lot until 1980, when she upgradec to aircraft cornmar~der . A Distinguished Graduate of the SAC Combat Cr@w Training SchQ:) I, her outstand!ng performance recora with the 4Jd Air Refueling SQUadron, earned h'er the Air Force Commendation t1eoal, and Humanitarian Service f1edal. Assigned to the 924th Air Ret·ueling SQUadron, as a f!ight Commander from 1981 unt i I 1983, her combined avion1cs and aviat !On background, were ~. ey in her seiection as B-52/KC- I 35 Test D!rector, 4200 Test and fvJluat ion :_:,,~l!adr on, C.a5 tlf' AfB, C~ liforrd::! As Test Diredor, Stlt' ~·epresented '5AC. and A.Fl C ir• arrert ance testing ~rrd evaluatwn of ,'itrcrew trai ning oev tce·.~ for tne B-52 ·._) ffen::.:vt- Av:onics Systen, and KC - 1::5 f 1 igt't 5imulator -:. Her p~rf orrfl~ir· cr ~Jr''ed her the ~ ir~; t Oar.!eaf Cl us ~ e r t\ t t:e Jler1tor 1 l~J:;, ~-i t-rv !uJ

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TABLE OF CO^n,ENTS

11 Preface

List of l!iustJ3tions vi

introduction 1

Why a New Land^? System? !

Limitations of the instrument Landing System (115) i

nicrowave Landinc System (MLS) Des'.gn Requirements 2

MLS - Goma OoeMt'cnal

Standard Connquration 4

Advantages of rr.eMi.s 4

^lyinq tne 'iLS 8

Tne Future - Joint tactical Microwave Landing System 10 (J'MLS)

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Bibüoarapny

Glossary

index

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LIST OF ILLUSTRATIONS

FIGURE ! - A'dSK.-i Terrnnu-ii *\ppf oai.'. T'l.-itH ■ i IL-i/SiriL-l

^wy 6, Valdez, ^ifiska

FtGl'RE ? - MLCi (cockpit) control and annuni'iator panels.

FIGURE 3 - Comparison of Microwave Landinq Sysrpm and instrument Landing System

FI6URF 4-JTML5 Advantaqes ,., ..

VI

"!=lying elf\ b~st b~ rhar:K.tertzed as hours or boredom pt:nctuated tly bri~f ~nments of start, terro"... r~ P'!ot that made this observat ion may weo!l hav~ t)'"'~" reha~ring to thE' ~~'To! · e)Cttertflnc~d d\r."ing a "real weather m!f'IF.IUTnS

annrGctctt · The pL.'rpose of this hamlbook 1s to tr.troduce )'OU to one of tec ·= ~1ology·s answers to ~"~ t@f"!·or of transit ion, approar.n and Iandin~. or rr·':'-:=.ed approach in m~mmum weatner co~dtttons . A basic f arntHJrizatior. with ~f'~ history. ~igr: and appticahon of tht' Microwave landing ~-.ystt'ff' shoo to d!(l

you m underStanaing tlow to best use thts ~w system to your advantage.

Si~ce 1949. the aviation communtty has used the tnstrumtnt landing syst'-fn <'L.S) as tne wor!dwid~ standard for r:wectston approaches. Thf mttitary emr. 1oy~ thftr own bacr.up system, the ground controneo prectsion approach radctr (PAR). Both systfms werfl dest~ timited to a stngle aporoach path and an op~attonal miniMa of a 200-root cetlmg and forward vtstbiltty of one-half m: if' < I : 12)

The tLS M'd PAP systems have constttutN the cornerstoM or military l :i'1 t~ mg 5ystem~ t·or tt)tl last Ultrty-rtve years. Ounng this ttme. thta sys•~ms ~~av~ urdergo~~ rna~nr mod;ficatton$ whtrh have resulted tn s1gnifirant :'np~ovtmlents 1r. performaflce and reHaoiHty Witn the addrt;on ot many cost ty 'mr;r·ovements to protect ~~gamst stgnal degradation, tower m!n.tma Cdfstgnat.ed C?. ~ :,/ Ca~ !•!} cot:~d b~ obtamfld on the tLSc 1:12) However, the systems sttll ·· ?" ··at~~C1 severe!y l Jr:-1'tea frcm a oesign standpoint.

Limitatton:s atbi..JLS

n. !:, .-~ are f!V~ ~a_; or ~eC..,flTC.al lirnitano~s to the ILS syste-m. rnfl rno-st :. '~": !· icaf't def 1 C '~"fY !5 1t 5 susc.ttpt;bility to stgna! :r.terfflrer~c~ . Multipat~

.. t-. :€'n !Ons from topograon c featur~s. bui !dirgs, and ott-,er airc~aft. airoor"e or o·· •r.E' gr0t:nc. ··fl~.v !t ~ r. ·:. ig'iat ;"lt~rf~r~ce to both ior~li;er anc! gli<le-slope inorrrat iof'. P~·s error.em1::. data mar.it"t~sts itse!f in me rnom~tary loss of :-:z_;r;ai chJ'"mg tiH., dPfXoacr·. or mtsat•gnr1flnt of cente~Hne ana glide-ptlth :' .. :.1r~ at io"1 . The sef" O'"lO limitation is due to stringent requiremef~ts on ?.~'. t-l"r;a ~!acement. To assure prop~ s;gnal propogat ron, the ILS gl'de slope :1r. te~n .::; ~·equtr~s ~nat ~~a void of obstac 1~5 for at le~t I 200 feet direct !y tn frn"~ of tr.e antenna "!" h~~~fon·. t~rain at the ground s1teo becomeos t~P prt!r!ary

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determining factor in beam patterning Obstacle? often result ir DMna spots on tne approaches, as a resu't, many airfield? are deemed unsuitaDle for IL5 use. Third, tne IL.S glide path signal is designed to De Pounced cff the ground; as a result, changes in ground patterning or moisture content due to such severe atmospheric, effects as snow, heavy rain, or sleet adversely affect transmission of the g'ide slope signal ^rth, 'rnerent in th»-' use :.")!■ VHP and ÜHF frequencies, is tne limited 40 channel frequency availaPiliry with

even greater service limitations in some areas due to frequency assiqnrneiVs already in existence The fifth, and most s;q: '*" anr limitation to ar ^'aff'i control is the single beam design Providing narrow course guidance (*- ^ to b degrees), combined with a single glide path, limited to 4 degrees elevation a^craft are often stacked in holding patterns to faantate the straigrit-i^, approach sequencing. The lacK of system fle^'bility and limited guidance 'oake sequencing of prionity traffic a problem, and often require overflight of populated areas iM2) (10:14) Recognizing these constraints, tne federal Aviation Administration (FAA), international C'vii Aviation Organtzatton (1CAO), ana international user governments began fne search for a worldwide replacement for the present non-visual precision approach and landing system suitable for both military and civilian application

NfiflL beg innings, z-MLSL-dfisi^n reau-irements

in 1971, the Radio Technical Commission for Aeronautics Special Committee No. 117 (RTCA SC-117), a group representative of government, industry and aviation system users, presented a Development Objective (00-148* which established the guidelines for the ensuing search tor a replacement for the present ILS in 1973, the International Civl Aviation Organization CCAO), provided the operational requirement for "A New Mon-Visual Precision Apcroach and Landmg System." Requirements for a new microwave landing system were

a Provide a high integrity signal in space, which is insensitive to a physically dense airport environment,

b. Permit all-weather operations with an extremely high degree of safety,

i. Provide for a common evil/military system in accordance wtn nat mf,-! I pnliry,

■:J P'oviqe eor low cost veiMons winch will perm't the e.^te^s!'.••■ ;;? service to low density airports on an economma1 bas's,

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e Fuih'l operationa! needs of V/STOL aircrar'r for approach anü lard'nq services,

f fjrov'dp a ftexiP'e guidance system which will aid in noise ^natement,

g. Provide tr>e rapaDütty for generating curved approaches tu runways as a means for increasing airport capability.

h Permit less separation (2500 feet) of parallel instrument flight •;;!es (IFR) runways,

i Provae for tactical military versions of the system on a compatible basis,

j. Provide a system design which will be internationally acceptable as a replacement for the ICAO standard VHF/UHF IL5 and will meet worldwide requirements until at least the year 2000 (1:16)

The MLS - Going Operational

Between 1971 and 1978, numerous systems were tested worldwide, and the u AO selected the Time Reference Scanning Beam (TRSB) technique as the new wo'"!d standard. A^ter its selection, the new TR5B Microwave Landing System spent thirteen years in design, test, and evaluation As intended, the development and proofing of the system was truly an international effort A con"actors informational manual described the worldwide status of the MLS. m 1983 as follows

ICAO: Standards ana Recommended Practices (SARPs) for the angle portion of the system have been completed. The Precision (DME/P) SARPs are expected to be completea in 1963 U.S. FAA. A request for proprosal was issued in April 1983 for 172 systems plus options to be orocured with FY-i962 through FY-i986 funds By 1939, me FAA expects to be installing 100 systems per year until they have 1,250 installations. These first !72-p!us systems wi!1

oeco^e operat!ona! between 1986 ana 1988. U.S. Non-Federal: The wond's first MLS (a Bendix system) was commissioned for !FR operations at Valdez, Alaska, on 16 November '962. Additiona1 comrnissiomngs are expected in 1983. International: The Japanese CAB is testing the second iteration of MLS built in Japan The British CAA has ordered a Bendix system ana wM start testing at Stenstead near London in September 1963 Fransport Canada '-s awaiting delivery of a test system which will be

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used to develop their specifications for procurement in 1985. France has a system in development. The U.S.S.R. »•■ testing their second iteration TRSB system in Leningrad'^ 8:10)

Worldwide, 400-500 microwave landing systems are projected to be operational by 1990 Total transition from ILS to MLS is estimated to include 5,000 systems with an operational target date of the ye3r 2000. (8 10» As of \%4, Valdez, Alaska (Fig. !) remains the only operationa! MLS system wth'n the United States. A second system is presently undergcng testing at tne Af Force's designated lead-in base, Shemya, Alaska. Equipment certi'^atron includes spec.ification and performance testing of airborne ana grounu eauipment as well as the establishment of FAA maintenance reporting ariü technician certification. (1:2)

Standard Configuratixm

An impressive new system, the MLS is functionally divided Into five separate parts: (a) approach azimuth angle guidance, (b) back azimutn angle guidance (c) approach elevation angle guidance (d) range guidance and (e) data communications These functions reflect a standard configuration MLS A description of the associated ground equipment's functions are as foiiows'

The approach azimuth station provides the angle guidance ana data communications information for the system. Tne data communications information refers to the status of the equipment and transmission rehaoility

The approach elevation station to provide approach elevation guidam e angle Range guidance is provided through the precision distance measurinq equip-

ment (DME/P) similar to the previously used DME systems but with upgraded accuracy and increased channel capabilities.

The MLS identification is alphabetic, four k'.t^s long, and is preceded by the letter M (7:321)

Advantages of the MLS

Long in development, the Microwave Landing System (MLS) promises to pay nack even longer in benefits fhe new MLS fu'fills ill of' the requYemenis ot K.AO Developmeni Objective 14c!, boasting the /insweis to problems cuMted by difficu't terrain features, increased margins ot safety during instrument conditions, approaches over populated areas, and servere weather cond'tions

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which hindered the uperation of the old ILS system HOW does the MLS ne'!ver

on all these oromises? It delivers with urer'se def'hitioh of a" arcned approach path from any point in space the pMof selects This sta^-v-'he vi air navigation aid Prov!des this curved path guidance th'-oucjh p^ecse ^"■:v,iM-1

elevation angles, and range information. A" aspects of this dat^ ■....:'■ ve displayed on conventional course deviation indicator'.-, ;.r tncorporated "■'.; i^ew CRT cockpit displays.(Fig.2H2 4.5) The MLS aHows femendous nen'l'üty <r approach paths while assuring terrain clearance tn'-'.-juq^ oala inne'^''' in ,he grounc ecuipment, This increased operationa1 cayair'fty represents thn ?AA's principle motivation in supporting the deveiüpmer't. and deployment c* Mi 5 increased prec'sion of the approach guidance, ease of system mst-^at'om 'rnproved reliaoility, a decreased susceptibO'ty to electromagnet": interference (both on the grounc and in the ar) ?'-i.\ the far higher numpe'' of availaoie tranmission channels result m the M.i5 Deinq rated technomc'caity superior to the present ILS.

Airspace management is also enhanced hy the ML 5 F lying the MLS .?!!ows a ueqree of flexiPility for Air Traffic Controllers previously realized only m ytn conditions Course guidance for- the MLS depicts a curved path SNT";..•?'■ fo :: visual nigh key, or low key f ligntpath. Therefore, the MLS affords an increase in numbers of ai'T^aft wtvch can De effectively nandled under irs'iume^t conditions (:!ying the IL5, aircraft must carfuliy sequence along the i-'afow oeam guidance. The flight path closely resernples a VFR straight-in approac': path. The '-esu'^ 's lack of flexibility, sequencing qelays and overcrowd'r'.g " contrast the MLS is responsive to performance criteria of different, ai-cra^ and 'imitations of terrain, and overflight restrictions Using the .9 to 20 degree MLS elevation scan, a oilot may select varied approacn angles (to include two-step glide slopes), best suited to his aircraft and circumstance The separate 40 degree horizontal, wide sweep plane, permits use of umcue curved flight paths These curvec approach patns, similar to a VFR Might path, join the projected runway center!me at a predetermined point on the approacn These new instrument options resu1t m less aelays in approach sequencmg w't^m the airport *-ermina! area The ability ''or -i controller to safely seouem'e

■arge and small aircraft onto the final approacn, path provides at: addec im''-"^ of flex'Dii'ty and safety when clea'ing with restr'ctions of wake turbulence ano foise abatement. One of the most unusual features of the MLS is it provme'? '-issed appr02cn guidance. This guidance includes glide/climb oath data to assure S3fe transition with terra'n ano oostacle clearance. This guidance is nrovaed withm a 4C degree fan on the departure eno, extending to 5'"Tf, ami

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inside enclosed 'irea ^la^^^tJ the 3^l^^;ut'■! antenna is the Ml.5 montcnng equipment CRT here rjTüplg'j? real time information 61 veil «^ a record of past performance of MLS approacfi aid (2 3 Fig 1)

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MLS cnntrol panels Each prjnel contains controls for frequency ''■^.nanne''), az'irnutn (cours?1', and qi'd«? slope selRctJon Also visib't are fdil" and "warninq" lights One additional panel (not shown) calls up specific information I'Ke runway cend't'on" and " minimum qiideslope" (2 4 Fiq 2)

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5,000 ft. AGL it'Cj. 3) (5:Ch,4:F'g.5) Th's saf8ty factor aüows lr<e nMot tn depart the terniinal airspace arc safe!y transit'O" to '3 aesignateti oatte'r. -eentry point (5 64)

Qes'gnea with reliability ana ma'ntainaDility "• ^'^n, ML.S ground eouipmer-t car ne remotely operated and monitored oy matntenarce or tower pe'vor-'-ie! Tni5 new system's digital deskjn of the ground euuipment, outlr to ;at ''^^te quicK cnange-out of line-replaceable units (LRU), »eatyes redunaart ■/y.-i.e'Ts and "fatl-soft' technology All ground equipment has neen des'g^eo with .; self-mon'tormg capability which can be evaluated at n.un-roi'ocatea y??'? ■-u':M

as the airport tower, or maintenance facii'ty.ü.lOS

ELllNfi, IMLÜLS

Although MLS cockpit, equipment varies from tne old !LS receiver, the actual guidance can be displayed on the present flight director systems most of our military aircraft, use The ma;or notable system difference to the pi'ots win oe the replacement of the ILS receiver with an MLS receiver The Ml.5 receiver, once the frequency allocations have been made, will allow the pilot to aiai m one frequency which wiM provide course guidance and associateo OMLVP information. Presently, some or' the develoomenrai systems require two separate receivers one for tne ÜL3 and one tor OME/P. A more proncunceo difference wi" be the ability of the pilot to select the glides'ope ne determines best serves his performance requirements it further give mm tne ability to set in a degree of centeriine offset. This offset function a',!ows the MLS to establish a curved flight path to the runway Certain safety parameters are established within the ML.5 approach system, wmcn will not allow the pilot to set unsafe parameters into his onboard equipment. Each operational MLS will nave a maximum and minimum glideslope, and a maximum azimuth tcou'se offset), selectable by the pilot. Should the pilot select parameters outside those established in tne system, a visual and aural warning is introduced from the ground system In the future, some MLS multiplex systems will "ive the ability to (.a" up six seperate areas of airfield data, to include ' ücity identification, faci'-ty category, minimum glide slope, runway identif'/.ation, runway condition, and azimuth This system providec. even mrre safety information *or the aircrew flying the approach (2 41

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Firii.ii?^ v^O'-'PARIS N OF MICPOWAVE LANDING SVSTEM qpd INSTR; ME NT LANDING 5VSTEM

MicrnwjvtJ Unijmq ii|i:t(»rn

2,000-« rollout and missed approach \ /

'-lus^d approach quidanc«*

40; wide(±20')7 \

Codtifuioos dis<4rii.? rrie^jijremfnt

k'"

\V-^ No unique approach path

4- \

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20"' , . ^-4420,000 rr

V NM;

20NMI

Guidance t'CTdefp, 1 2UB widt» (♦ hO") oo/t-raqe to 20,000ft

'nstrurpwt larding syjtem

No continijo'j: di5tänc^ measurenipnt t^o discrete ranqt» mdicatiori'j prnvded b'^ fan mirkers

^?.

Missed approach"""-- guidance in azimuth unlu ->j^_

riidd"^

Unique approach path

E ■«tended / njnwag

i / center line

35NMI Approx- Appro* —

\ ._-——' 20NMIRanqe

Source: Federal Aviation Admin, ^ 1 • h ^ t.',,-, ^ \

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The Microwave Landing System promises to continue providing posUive improvements to the international theater of t!ying. Future aopl'fations include portable h/ILS systems to be used in military deployments. Joint service testing began in 1983 on a joint tactical microwave iand'ng sycten (jfMLS) With this exceptional new system, the anxiety of an approach over threatemnq terrain in poor weather will be significantly lessened. Highly depenaaD;e, fiLS can assure reliable data from altitude through touchdown or missec; approach. (3.11)

The new JTMLS is envisioned as the heartbeat of real world ncDitny scenarios which might require approach information in an austere landing environment. The JTML5 is a lightweight, portab!e landing system basec: on f ii.S technology Set up time is projected to be IS minutes, and can be accomoHsned by a crew of two technicians. This new system has received much ai lent'on from the Army They view the JTMLS as a primary aid in assuring a positive position of mobility, If an engineering force can establisn a "wartime' iandirg stnp^ this system can assure reliable instrument approach data in a zero-zero environment. This new system has many advantages wnich make it a Key player

in future mobility planning.(Fig 4) (3:Fig6) In the year 2000, MLS approaches will represent the standard. Approach

plates calling for 5.2 degree minimum glide slope for noise abatement, a 40 degree curved final,, and a roll out point 1/2 mile from the runway threshold will be common.

This handbook has endeavored to familiarize you with the history of the microwave landing system, the nuts and bolts of the system ana its flight application. MLS is the wave of the future, it's peginnings are here ar-c: now Roth the MLS and the JTMLS, presently under development, wi!! sign'fcantly enhance fliqnt safety and mission accomplishment (3:6)

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FIGURE 4 - ..:' MLS ADVANTAGES

CornpVy approach p<»th; Pilot ?plectjb'f courrn/ ■jhdfs'ope

1 15 minu'e j<?*->jp bi^ 2 men No operators required /

Low powor/Less SUSCep^lblP to ijetec^on

5 B-ä^eri; powerpcJ

^.^■yx-

^y

z / s

4 Mijlti-p^th r*}iii tion

f Simultaneous guidance to all aircraft in area

7 interoperable '-nth olher services, NATO

i? Low (nioirrtums with qr»at*»r

safety

n

(3 11 Fiq6)

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BIBLIOGRAPHY

1. Federal Aviation Administration., Ndtiona! Micr-owave Landing System Washington. July W1

2. Howard., Byron L. "The Microwave in Your Future" MAC Flyer Washington, March 1962.

3. Howard, Byron L "Flying the Microwave Landing System", MAC Flyer Washington. October 1982

4 Jensen, Richard 5., "Improving the ML5 Through Enhanced CockDit Displays", Navigation, Vol 26, No.2, Summer 1981

5. Kelly, R.j. and LaBerge E.F.C. "Guidance Accuracy Considerations foi the Microwave Landing System Precision DMF", Navigation, Vol 27, Ho.'1, Spring 1980.

6. Office of Technology Assessment, Airport System Development QTA-STI-231. Washington. DC , August 1984

7. Prosser, Lester L., "Current Status of the MLS Program", Navigation. Vol. 30, No 3, Summer 1963

8 Realien, Henry W and Kelly, Robert J, Microwave Landing System: Ihe New International Standard. Bendix Corporat'on Communications Division, Baltimore, Maryland, 1981

9 Reed, W.C MLS Becomes Operational, Bend*x Communications Divisio;-', Towson, Maryland, 1983

10 Subcommittee of the Committee on Government Operations House of Representatives, 95th Congress, Second Session, FAA Procurement of a Microwave Landing System. January 1978.

11 Williams, Richard D . "ILSOULMLS In", Compat Crew, Castle AFB. CA, November 1983

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GLOSSARY ATC - Air Traffic Control

CAA - Civil Aeronautical Association

CAB - Civil Aeronautics Board

CAT ll/CATIII - Catefory two or Category three (instrument minima)

CRT - Cathode Ray Tube

DME - Distance Measuring Equipment

DhE/P - Precision Distance Measuring Equipment

DO - Development Objective

FAA - Federal Aviation Administration

ICAO - International Civil Aviation Organization

IFR - Instrument Flight Rules

ILS - Instrument Landing System

JTML5 - Joint Tactical Microwave Landing System

LRU - Line Replaceable Unit

ML5 - Microwave Landing System

PAR - Precision Approach Radar

RTCA - Radio Technical Commission Aeronautics

SARP - Standards and Recommended Procedures

TRSB - Time Reference Scanning Beam

UHF - Ultrahigh frequency

VHF - Very high frequency

V/STOL - Vertical Short Takeoff and Landing (aircraft)

13

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INDEX

Airspace Management 37

Curved path approaches 3 9

Design limitations (ILS) 12

Instrument Landing System (Ü..5) 1 2

Joint Tactical Microwave Landing System (JTMIS). .10-11

Microwave Landing System Advantages 4_3 Capabilities 5-9 Flight instruments 58 Flight paths ' g" Ground Equipment 4 Future applications 10

Missed Approach Guidance 5-9

Operational requirements (MLS) 2-3

Safety features 5-9

14

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