ac 139 - inspectarea aeroporturilor

AdvisoryCircular

Subject: Aerodrome InspectionProgramme and ConditionReporting

Date: 1/5/94

Initiated by: Mr E Evans

AC139-03A

1. GENERAL. Civil Aviation Authorityadvisory circulars (AC) contain informationabout standards, practices and proceduresthat the Authority has found to be acceptablefor compliance with the associated rule.

Consideration will be given to other methodsof compliance which may be presented to theAuthority.

When new standards, practices or proceduresare found to be acceptable they will be addedto the appropriate advisory circular.

In addressing a subject the use of theimperative “shall”, a term not normallywelcome in an AC, is because it is associatedwith mandatory provisions of the Rule itself.

Each reference to a number in this AC, suchas 139.15, is a reference to a specific rulewithin Part 139

2. PURPOSE. This Advisory Circular (AC)provides methods acceptable to the Authorityfor showing compliance with the aerodromeinspection programme and aerodromecondition reporting requirements in Part 139of the Civil Aviation Rules (CAR).

3. FOCUS. This material is intended for theapplicant for, or the holder of, an aerodromeoperating certificate. It is also recommendedto the operators of non-certificatedaerodromes.

4. RELATED CAR. This AC relates specificallyto Part 139 Rule 139.117 Aerodromeinspection programme and Rule 139.123Aerodrome condition reporting.

Graham MarshManager Rules & StandardsLower Hutt

Published byCivil Aviation AuthorityPO Box 31441Lower HuttISBN 0-478-06913-8©New Zealand GovernmentPrinted by: Apex Print Ltd

Petone

Aerodrome Inspection Programme and Condition Reporting

I n t roduct ion

1. While some hazardous aerodrome conditions develop virtually instantaneously, others aregradual. It is important to have an aerodrome inspection programme that monitors specificareas so that small defects do not develop into significant safety hazards.

2. An effective aerodrome inspection programme is an essential element of preventivemaintenance and of the aerodrome internal quality assurance.

3. Under CAR Part 139 all aerodromes serving any aeroplane, having a certified seatingcapacity of more than 30 passengers and that is engaged in regular air transportoperations, are required to have an aerodrome operating certificate. The operator of eachcertificated aerodrome is required to establish operating procedures to ensure that promptcorrective action is taken to eliminate unsafe conditions on the aerodrome. The aerodromeoperator is also required to advise aircraft operators of any aerodrome condition which mayaffect the safety of aircraft operations.

4. This AC suggests components, responsibilities, and items for regularly scheduled,continuous surveillance, periodic condition and special inspections for use during any ofthese inspections and for aerodrome condition reporting. This guidance can be modified asnecessary to meet local situations. The information and suggestions in this publication serveas a basis by which aerodrome operators may develop their own aerodrome inspectionprogrammes.


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Table of Contents

CHAPTER 1 — AERODROME INSPECTION OVERVIEW1.1 Responsibility .................................................................................................11.2 Knowledge and equipment for aerodrome inspection ......................................11.3 Components of an aerodrome inspection........................................................2

CHAPTER 2 — REGULARLY SCHEDULED INSPECTION2.1 Introduction ....................................................................................................32.2 Paved Movement Areas..................................................................................32.3 Unpaved Movement Areas..............................................................................32.4 Runway and taxiway strips and safety areas...................................................32.5 Markings and signs ........................................................................................42.6 Lighting ..........................................................................................................42.7 Visual navigation aids.....................................................................................42.8 Obstructions...................................................................................................42.9 Construction...................................................................................................52.10 Aircraft rescue and firefighting ........................................................................52.11 Public protection.............................................................................................52.12 Wildlife hazard management ..........................................................................5

CHAPTER 3 — CONTINUOUS SURVEILLANCE3.1 Introduction ....................................................................................................63.2 Ground vehicles .............................................................................................63.3 Construction...................................................................................................63.4 Public protection.............................................................................................63.5 Wildlife hazard management ..........................................................................63.6 Potential problems..........................................................................................6

CHAPTER 4 — PERIODIC CONDITION EVALUATION4.1 Introduction ....................................................................................................74.2 Pavement areas .............................................................................................74.3 Markings and signs ........................................................................................74.4 Visual navigational aids..................................................................................74.5 Obstacles.......................................................................................................7

CHAPTER 5 — SPECIAL INSPECTIONS5.1 Introduction ....................................................................................................85.2 Paved movement areas..................................................................................8

CHAPTER 6 — FLIGHT CHECKING OF VISUAL AIDS6.1 Introduction ....................................................................................................96.2 Requirements for specific flight checking ........................................................96.3 Flight checking criteria....................................................................................9

CHAPTER 7— AERODROME CONDITION REPORTING7.1 Introduction ..................................................................................................107.2 NOTAM........................................................................................................107.3 Information...................................................................................................10


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CHAPTER 1 — AERODROMEINSPECTION OVERVIEW

1.1 Responsibility1.1.1 Aerodrome Inspection. Aerodromeinspection is a primary responsibility of theaerodrome operating certificate holder. Primaryattention should be given to such operationalitems as pavement areas, safety areas,markings and signs, lighting, aircraft rescue andfire fighting, fuelling operations, navigationalaids, ground vehicles, obstructions, publicprotection, wildlife hazard management, andconstruction. The responsibility for inspection ofall or some of the aerodrome areas may beassigned to other tenants, but with aerodromemanagement retaining overall inspectionsupervision. Management cannot delegateresponsibility for operating the aerodromesafely.

1.1.2 Inspection Frequency. Thefrequency of inspections should be determinedby identifying areas critical to the ongoingsafety of aircraft operations, taking into accountthe following factors —

• frequency of operations• duration of operations• types of aircraft served• the aerodrome environment• complexity of the facilities• size of the aerodrome

The reasons for establishing the frequency ofinspections should be documented, andsubmitted to support the contents of theexposition, addressing the certificate holder’ssafety inspection programme.

1.1.3 Inspection Recording. An effectiveaerodrome inspection requires a procedure forreporting deficiencies so that they can becorrected. The aerodrome operator shall notifythe Aeronautical Information Service (AIS) (forthe issue of a NOTAM), as soon as practicable,of any aerodrome condition or defect whichcould have an immediate and critical impact onthe safety of aircraft operations. Whencorrective action has been taken, the NOTAM isto be cancelled. For even the smallestaerodrome, it is desirable to use an aerodromeinspection checklist which constitutes a writtenrecord of conditions noted, and acts as a checkon the follow-up actions taken

The scheduled use of a dated checklist willassure the regularity and thoroughness ofsafety inspections and follow-up of deficientitems. It is most desirable to use a format inwhich each inspected area of the aerodromecomplex is positively noted.

1.2 Knowledge and equipment foraerodrome inspectionPersonnel who conduct aerodrome inspectionsshould:

(a) know the location and types ofaerodrome facilities and their designcriteria;

(b) know the standards applicable to theaerodrome;

(c) have a vehicle equipped with —

(i) two way voice radiocommunications with the airtraffic services unit, ifprovided for the aerodrome;

(ii) a flashing or rotating beaconfor night time inspections; and

(iii) either a beacon or chequeredflag for day time inspections;

(d) know and use correct radiocommunication procedures andtechniques;

(e) be supplied with check lists coveringthe various inspection areas. While theformat of check lists vary, it is importantto develop a check list that is useful forthe aerodrome and its operation. Ifcertain inspectors will be responsible foronly certain items, separate check listspertinent to those areas may bedeveloped. A sketch of the aerodromeshould accompany the check list so thatthe location of problems can be markedfor easy identification;

(f) read the previous inspection report;

(g) if construction is in process, be familiarwith the safety plan for the project; and

(h) if the aerodrome is certificated underCAR Part 139, be familiar with theaerodrome certification expositionrequirements about aerodromeinspections.

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1.3 Components of an aerodromeinspectionAn effective safety inspection programme hasfour components —

• a regularly scheduled inspection of physicalfacilities

• continuous surveillance of certainaerodrome activities, such as fuellingoperations, construction, aerodromemaintenance

• a periodic inspection programme for suchthings as surveying approach slopes,checking for obstructions, the checking ofvisual aids, operation of lights

• special inspections during unusualconditions or situations, such as inclementweather or following maintenance activityon the manoeuvring areas.


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CHAPTER 2 — REGULARLYSCHEDULED INSPECTION

2.1 IntroductionThe regularly scheduled inspection consists ofspecific observations of aerodrome physicalfacilities on a frequency determined by theaerodrome operator. This inspection shouldconcentrate on the areas described in thissection and if deficiencies exist, indicate theitem and identify its location on a sketch. Takephotographs, if appropriate, to document thecondition.

2.2 Paved Movement AreasThe condition of pavement surfaces is animportant part of aerodrome safety. Pavementinspection should be conducted beforebeginning flight operations to ensure pavementsurfaces are clear. As a minimum, a dailyinspection should be performed of all pavedareas as follows -

(a) check the pavement edges to assurethat they are no greater than necessaryto allow water to drain off thepavement. A lip height no greater than25 mm to 35 mm is usually sufficient toallow proper drainage. Any edge of75 mm or more would be considered tobe a hazard to aircraft;

(b) report and monitor any surfacecracking;

(c) determine if there are any holes. A holeexceeding 125 mm in diameter thatexceeds 75 mm in depth with a sideslope of 45 degrees or greater, isconsidered to be a hazard to aircraftand should be dealt with immediately;

(d) check the condition of pavement areasfor scaling, spalling, bumps, low spots,and for debris that could cause damageto aircraft;

(e) check for vegetation growth alongrunway and taxiway edges that mayimpede drainage from the pavementsurface or slowly break up the pavedsurface; and

(f) check for vegetation growth in cracks.

2.3 Unpaved Movement AreasThe condition of these surfaces are asimportant as for paved surfaces and should besubject to the same level of thoroughness —

(a) determine if there are any hazardousruts, depressions, humps or variationsfrom the normal smooth surfaces;

(b) determine if there are any holes thatcould cause directional controlproblems for any aircraft;

(c) check for debris and other foreignobjects;

(d) check the condition and length of grasssurfaces. The height of the grass shouldnot be excessive; and

(e) check for vegetation growth along theedges that may impede drainage fromthe movement areas.

2.4 Runway and taxiway strips andsafety areasThe inspector should know the dimensions ofthe runway and taxiway strips and runway endsafety areas at the aerodrome and:

(a) determine if there are any hazardousruts, depressions, humps or variationsfrom the normal smooth surface;

(b) check to ensure no object is located inthese areas, except objects that mustbe in the areas because of theirfunctions (such as runway lights, signs,or navigational aids);

(c) determine if the base for any equipmentin safety areas is at grade level;

(d) check to ensure that the ground has notbeen eroded from around light bases,manhole covers, or other fittings thatshould be flush with the surface; and

An exposed high edge could be ahazard to aircraft and should be filled in.

(e) check for any damage that might becaused by animals.

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2.5 Markings and signsAerodrome markings and signs provideimportant information to pilots during take-off,landing and taxiing. The inspector should knowthe appropriate markings and signs at theaerodrome:

(a) check markings for correct colourcoding, blistering, chipping, fading, andobscurity due to rubber build-up;

(b) check that markers are correctlypositioned and in good condition;

(c) check signs to ensure they are thecorrect colour coding, easy to read,secure, and that all lights are workingand not obscured by vegetation or dirt;

(d) check that signs within the strip areasare frangibly mounted; and

(e) check to see that signs are not missing,that they have the correct legend andorientation, and whether they are inneed of repair.

2.6 LightingAt night and during periods of low visibility,lighting is important for safe aerodromeoperations. Lights come in different shapes,sizes, colours, and configurations and can beflush mounted or elevated:

(a) check to ensure that the following areoperable, if installed, and that theoptical systems are not obscured byvegetation or deposits of foreignmaterial —

• runway threshold and end lights

• runway, taxiway, and apron edgelights

• runway centreline and touchdownzone lights

• taxiway centreline lights and apronguidance lights

• holding position lights

• runway end identifier lights

• reflectors

• floodlights for signs

• visual docking systems

• apron floodlighting

• obstruction lights.

(b) report all damaged or missing fixtures,and lights that are not working;

(c) report any broken lenses;

(d) ensure that runway and taxiway lightsand runway threshold lights are theproper colour and are orientedcorrectly; and

(e) check that lights function properly,including intensity controls, through themanual or radio control features, andthat photocell controls function properly.

2.7 Visual navigation aidsThe inspection should concentrate on the visualnavigational aids as follows —

(a) ensure that the windsock area is clearof vegetation and that it can be easilyseen;

(b) check the windsock to ensure that thesupporting mast is upright, that thewindsock swings freely and, if lighted,that all lights are operating;

(c) ensure that the aerodrome beacon, ifprovided, is visible and workingproperly;

(d) ensure that the Runway End IdentifierLights (REIL) are flashing, and notobscured to an approaching aircraft;and

(e) check Visual Glide Slope Indicators(VASIS, PAPI) to ensure that their lightsare working, not obscured to anapproaching aircraft and that themountings have not been damaged ordisturbed.

2.8 ObstructionsThe inspection should concentrate on a visualcheck of any construction underway on or nearthe aerodrome that could affect aircraftoperations:

(a) check for any new or unreportedobstructions such as cranes, masts,advertising hoardings, balloons andsuchlike, that intrude into theaerodrome obstacle free surfaces; and


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(b) determine that obstructions are properlymarked and lit.

2.9 ConstructionThe inspection should focus on constructionactivities on the aerodrome to ensure that ahigh level of safety for aircraft operations ismaintained:

(a) determine if stockpiled material andconstruction materials are properlystored to keep them from being movedby wind, jet blast, or propwash;

(b) check all construction adjacent tomovement areas to ensure areas areidentified with conspicuous marking andlighting;

(c) determine if heavy constructionequipment (such as bulldozers andcranes) are marked and lighted andparked clear of the runway and taxiwaystrips and any safety areas;

(d) check to determine that stockpiles andstored equipment are not left in aposition that would infringe the obstaclefree surfaces; and

(e) check to ensure that debris and foreignobjects are progressively being pickedup around construction areas.

2.10 Aircraft rescue and firefightingThe inspection should focus, if rescue andfirefighting is required, on the rescue firefightingcapability as follows —

(a) at applicable aerodromes, check aircraftrescue and firefighting equipmentavailability;

(b) determine that all required rescue andfirefighting vehicles are serviceable andthe required personnel are available;

(c) insure communication systems areworking; and

(d) determine the adequacy of thefirefighting agents on hand.

2.11 Public protectionCheck the serviceability of barriers provided forpublic protection and the functioning of anycontrol procedures.

2.12 Wildlife hazard managementCheck for dead birds or animals on therunways, taxiways, and aprons or other signsthat wildlife problems may be developing —such as large flocks of birds on or adjacent tothe aerodrome

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CHAPTER 3 — CONTINUOUSSURVEILLANCE

3.1 IntroductionContinuous surveillance is an alertnesspractised by personnel to look for defects at anytime they are on the aerodrome operationalarea. Continuous surveillance of aerodromephysical facilities and activities should cover atleast the areas described in this section.

3.2 Ground vehicles (a) determine if procedures and

arrangements for the orderly operationsof ground vehicles (including grassmowing machines) are being followed;and

(b) report any deficiencies, if appropriate.

3.3 Construction (a) check for unauthorised use of runways,

taxiways, and aprons by constructionpersonnel and equipment;

(b) keep a sharp eye out for potentialrunway incursions and otherirregularities;

(c) check all construction projects to ensurethat the safety plan is being followed bythe contractor; and

(d) ensure that construction equipment isnot operated in navigational aid criticalareas unless it is coordinated with theoperator of the aid.

3.4 Public protection (a) be alert for unauthorised persons,

vehicles, and animals; and

(b) ensure gates are serviceable and clearfor access by rescue and firefightingvehicles.

3.5 Wildlife hazard management (a) note any birds or animals on or adjacent

to the runways, taxiways, and aprons, todetermine if there is a potential wildlifehazard problem; and

(b) report any potential hazard created bybirds on or adjacent to the aerodrome.

3.6 Potential problemsCheck the following for any potential problems—

(a) control of pedestrian access to themovement areas;

(b) passenger loading and off-loadingareas;

(c) other movement areas frequented bythe general public; and

(d) debris on movement areas


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CHAPTER 4 — PERIODICCONDITION EVALUATION

4.1 IntroductionPeriodic condition evaluations consist ofspecific checks on a regularly scheduled basis(but less frequently than daily). Checks mayrequire use of specialist equipment and shouldcover at least the areas described in thissection.

4.2 Pavement areasCheck pavement surfaces for rubber build-up,polishing, or other conditions affecting surfacefriction.

4.3 Markings and signs (a) check pavement markings to ensure

they are correct and in good condition;and

(b) determine if markings are visible atnight, especially examine for rubberbuild-up in the touchdown zone areas.

4.4 Visual navigational aidsAn inspection programme for each visualnavigation aid is essential to confirm theirongoing accuracy and reliability —

(a) visual navigation aids inspectionsshould include regular checks of thepower supply, light emission andalignment using such equipment as aspotmeter and aiming and calibrationbars;

(b) ensure that power generator and circuitresistance tests are being conducted;

(c) ensure that operation on auxiliary powerwill cause no deterioration in any aspectof the lighting systems and that the timeto cut in does not exceed 15 seconds;and

(d) for the flight checking of visual aids,refer to Chapter 6.

4.5 Obstacles (a) if the aerodrome is required to provide

the AIS with data for the promulgationof aerodrome obstacle charts, surveyall take-off flight paths to confirm theaccuracy of the data;

(b) survey the other aerodrome obstaclelimitation surfaces established for theaerodrome for clearance fromprotruding obstacles;

(c) if an obstruction is found to infringe anobstacle limitation surface, eitherimmediately remove the obstruction ornotify the AIS with the correctedeffective operational lengths (EOL) forpromulgation in a NOTAM. If theinfringing obstruction is permanent,notify the AIS of the permanent EOL forpromulgation in the AIP; and

(d) the period for the conduct of the checksshould be determined, and included inthe aerodrome operating exposition, bya study of the aerodrome environmentto identify the likelihood of significantobstructions, such as tree growth,structures, and similar, being developedin the intervening periods.

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CHAPTER 5 — SPECIALINSPECTIONS

5.1 IntroductionSpecial inspections occur after receipt of acomplaint such as substandard braking action,or as triggered by an unusual condition orevent. A special inspection should beconducted after an accident or incident.Depending upon circumstances, specialinspections may include the inspection of any ofthe specific facilities or activities under theother three components. A special inspectionshould cover at least the areas described in thissection.

5.2 Paved movement areasAfter heavy precipitation an inspection andassessment should be made as follows:

(a) Water on a runway

Whenever water is present on arunway, a description of the runwaysurface conditions on the centre half ofthe width of the runway, including thepossible assessment of water depth,where applicable, should be madeavailable using the following terms:

DAMP - the surface shows a change ofcolour due to moisture.

WET - the surface is soaked but their isno standing water.

WATER PATCHES - significantpatches of standing water are visible.

FLOODED - extensive standing wateris visible.

(b) Snow, slush or ice on a runway

Whenever a runway is affected bysnow, slush or ice, and it has not beenpossible to clear the precipitant fully,the condition of the runway should beassessed.

Whenever dry snow, wet snow or slushis present on a runway, an assessmentof the mean depth over each third ofthe runway should be made to anaccuracy of approximately 20 mm fordry snow, 10 mm for wet snow and3 mm for slush.

(c) Unpaved movement areas

After or during a period of heavyprecipitation, check for ponding, andany surface softness which might affectthe bearing strength and braking.

(d) Runway and taxiway strips andsafety areas

(i) check storm water system toverify that inlets are notclogged and drainagechannels are free of debris.Note any standing water; and

(ii) ensure all drain covers are inplace and flush with thesurface.

(e) Maintenance and construction

(i) conduct a special inspectionbefore reopening a runway ortaxiway following anyconstruction or maintenancethat has been performed in oraround the manoeuvring area;

(ii) any time an aircraft has leftthe pavement and entered astrip or safety area check toensure that no ruts or holeshave been made by theaircraft tires or personnel andequipment during therecovery operation;

(iii) check for construction andmaintenance activities toensure that no hazardousconditions have been created(equipment left in safetyareas, unacceptablepavement edges created byground alteration work, rutsfrom mowing equipment); and

(iv) after construction ormaintenance operations,ensure that pavementmarkings are correct and thatany unserviceable markershave been removed.


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CHAPTER 6 — FLIGHTCHECKING OF VISUAL AIDS

6.1 Introduction6.1.1 The objective for the flight checking ofvisual aid lights is to confirm the accuracy ofthe guidance provided by visual approach aidsand to otherwise determine the conspicuity ofall the lights required for the aerodrome.

6.1.2 Flight checking is not a means fordetermining the serviceability of lights andvisual aids as this is best done by an effectiveaerodrome inspection, and preventivemaintenance programme as mentioned earlierin Chapter 4. The requirements for ongoingflight checking can also be minimised by suchprogrammes.

6.2 Requirements for specificflight checkingVisual aids include markings, wind direction indicatorsand the like.

Visual aids and aerodrome lights, other thantaxiway and apron lights, should be flightchecked in the following circumstances:

(a) prior to commissioning into service; and

(b) when any major component is replacedwith re-alignment or re-siting required;and

(c) when any visual aid is re-sited; and

(d) periodically to confirm ongoingperformance.

6.3 Flight checking criteria6.3.1 Approach slope indicators should beflight checked to confirm that each aid providesaccurate guidance within the tolerancesprescribed for that aid.

6.3.2 All other visual aid lighting should beflight checked to verify the appearance,uniformity, intensities of the light and that thereis no visual interference by any other light orobject.

6.3.3 The visual aid lighting performancecharacteristics to be verified by flight checkingprior to being commissioned into service shouldbe:

(a) T-VASIS and AT-VASIS

Appearance and uniformity

Channel width, glide path angle andILS/PAR coincidence

Top of red crossbar

Day and night angular coverage

Cut off light 1

Top of red light 1 and obstructionclearance

Cut in light 6

Range day and night, intensities andauxiliary power

(b) OTHER VASIS

Appearance and uniformity

Channel width, glide path angle andILS/PAR coincidence

Day and night angular coverage

Obstruction clearance

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CHAPTER 7— AERODROMECONDITION REPORTING

7.1 Introduction7.1.1 Under CAR Part 139 each holder of anaerodrome operating certificate is required toprovide information on any conditions whichmight affect the safe operations of aircraft.

7.1.2 Information on the condition of themovement area and the operational status ofrelated facilities shall be notified to the AIS. Thelocal air traffic service unit should also benotified to enable them to provide theinformation to arriving and departing aircraft.The information shall be kept up to date andchanges in condition reported without delay.

7.2 NOTAM7.2.1 Each holder of an aerodrome operatingcertificate shall ensure that if unsafe conditionsare uncovered as a result of aerodromeinspections, or from any other source, and cannot be immediately rectified, appropriateNOTAM are issued and that local aerodromeusers are aware of the situation. After providingthe information to the AIS, follow up to ensurethat the NOTAM were issued.

7.2.2 Once a NOTAM has been issued it isthe responsibility of the aerodrome operator tomonitor the reported condition and to eitherupdate the NOTAM information or cancel theNOTAM if the condition has been rectified.

7.3 Information7.3.1 The information provided for the issueof NOTAM should be clear and precise andshould contain:

(a) type of unserviceability or unsafecondition;

(b) extent (area) of the unserviceability orcondition; and

(c) duration (expected length of time) thecondition will remain.

7.3.2 It is important that the area in which theunserviceability or unsafe condition occurs isreferred to correctly. Runways and runwaystrips should be referred to by their runwaydesignator rather than the “long” or “main strip”.Similarly the difference between the runwaysand runway strips should be recognised and thecorrect terminology used.

7.3.3 In complying with CAR Part 139, theholder of an aerodrome operating certificateshall provide information to the AIS for theissue of a NOTAM on any of the followingaerodrome conditions which may affect the safeoperations of aircraft —

(a) establishment, closure or significantchanges in the operation of theaerodrome or runways;

(b) establishment, withdrawal or significantchanges made to visual aids;

(c) interruption of, or return to operation ofmajor components of the aerodromelighting systems;

(d) occurrence, or correction of majordefects or impediments in themanoeuvring areas;

(e) changes to and limitations onavailability of fuel, oil and oxygen(International aerodromes);

(f) establishment, withdrawal or return tooperation of hazard beacons markingsignificant obstacle to air navigation;

(g) erecting, removal of or changes tosignificant obstacles to air navigation inthe take-off, climb, missed approach,approach areas, and runway strip;

(h) significant changes in the level ofrescue and firefighting protectionnormally provided at the aerodrome;

(i) presence or removal of significantchanges in hazardous conditions due tosnow, slush, ice or water on themovement area; and

(j) any other occurrence associated withthe aerodrome which might be a hazardto the safety of aircraft operations.

ac 139 - inspectarea aeroporturilor

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