Aerial Evidence

Bankstown airport officials have denied that the airport has been expanded at any time between 1996 and 2000. There is clear evidence to the contrary.

Coming up below are sections from two aerial photographs of Bankstown Airport. Both were derived from Central Mapping Authority Photos. Nothing has been altered materially - see below for full details.

How many differences did you spot ? Fill this in, then test yourself against the answers in the Legend section (later you can press the submit button -bottom of page- to email your estimates and comments).

Legend (Spot the Differences)

First Length Extension

1 - 1997 11C Runway Threshold is permanently displaced some 160 m in from the Runway End Mark, an exceptional configuration (compare with other runways, and see below). This is approximately 80 m further along than where it was in 1996.

1' - 1996 11C Runway Threshold. If your monitor has sufficient resolution, you should be able to see the "scar" where the old threshold piano-keys have been painted over.

How can they denythe extension ? The length it defines has increased by 80 m ! That's length extension (difference) No. 1.

Second Length Extension

2 - 1997 11C Touchdown Zone Marking - A 30 m by 3 m mark near edge of runway that is supposed to be 150 m inside the Runway Threshold.

2'- 1996 11C Touchdown Zone Marking - Scar of painted over marking, approx 80 m inside latest mark. That's length extension (difference) No. 2.

Third Extension

1997 3 - 11C Runway Fixed Distance Mark - A 45 m by 6 m mark near edge of runway that is supposed to be 300 m inside the Runway Threshold.

3' - 1996 11C Runway Fixed Distance Mark - Scar of painted over marking, approx 80 m inside latest mark (3). That's length extension (difference) No. 3.

Fourth Extension

4' - 1996 29C Runway Fixed Distance Mark - Scar of painted over marking, approx 80 m inside latest mark. That's length extension (difference) No. 4.

4 - 1997 29C Runway Fixed Distance Mark(4)

Fifth Extension

5' - 1996 29C Touchdown Zone Marking - Scar of painted over marking, approx 80 m inside latest mark (5).That's length extension (difference) No. 5.

5 - 1997 29C Touchdown Zone Marking.(5)

Sixth Extension

6' - 1996 29C Runway Threshold. The old scar is approximately 80 m inside the new one (6).That's length extension (difference) No. 6.

6 - 1997 29C Runway Threshold.(6).

Seventh Extension

7 - 1997 29C Runway End Mark - This is now at the end of the R2 taxiway - no longer just at the end of the threshold. That's length extension (difference) No. 7.

More Expansion

Eighth Extension

8 - 1996 11C Pre Runway - The 11C runway end had a 50% width pre-runway extending approximately 220 meters from the 1996 end to the W2 taxiway. See definition later for what a pre-runway is - it's not part of the runway and does not add to the runway length useable in aircraft weight-limit take-off calculations.

The pre-runway has been clearly increased in width, formed into runway, and is now included in the TORA and TODA lengths.

Aerial photographs don't show what specifications this runway contstruction was built to, but there's probably differences in there too. That's size extension (difference) No. 8.

Ninth Extension

9 - 29C Pre Runway - The 29C runway end had a 50 % width pre-runway extending approximately 150 m from the S2 taxiway intersection to the R2 taxiway (and new end mark). This pre-runway has been clearly increased in width, formed into runway, and is now included in the TORA and TODA lengths. It's probably also now included in the current RESA specification. That's size extension (difference) No. 9.

Tenth Extension

10 - Runway 18/36 has been sealed for approximately 400 metres on the southern (36) end, but is clearly narrower than the top section. This has doubled its size.That's length extension (difference) No. 10.

Eleventh Extension

11 Theshold - The runway threshold is now 230 m further south. That's length extension (difference) No. 11.

Twelfth Extension

12 - 36 End Mark - The 36 runway end mark is 330 m south of the 1996 location. Note that this now makes this threshold a permanently displaced one - possibly due to obstacles like the aviation museum or other buildings planned for the south west corner. That's length extension (difference) No. 12.

Definitions of Airport Terms

The definitions herein are drawn mostly from the Airservices Australia "Rules and Practices for Aerodromes", as published in July 1998. They are provided in the public interest of informing the Bankstown community of aviation terms, so that the public may better ascertain the truth or otherwise of claims made regarding the airport development. Australia uses ICAO standards primarily, and these are often similar to USA FAA standards, and hence this information may be useful to airport communities elsewhere in the world.

While great care has been taken in checking the accuracy of this material, it is not intended and is not suitable for use for operational purposes, nor in training of pilots, airport planners, administrators or other airport staff. Any person requiring information for those purposes should consult the latest and official documentation.

Runway Touchdone Zone | Runway Fixed Distance Mark | Critical Aeroplane   | Runways   | Instrument Runways   | Non-Precision Approach Runway   | Precision Approach Runway   | Runway Strips   | Runway Threshold   | Runway End Safety Area   | Clearway   | Stopway   | Pre-Runways   | Runway Width   | upgrading   | Table of Width of Runways   | Runway Lengths   | Declared Runway Lengths   | TORA   | TODA   | ASDA   | LDA   | Enroute Supplement Australia   | Notices to Airmen   | Aeroplane Reference Field Length   | Aerodrome Facility Reference Code   | Runway Strength   | Runway Pavement Strength Data  

• The Critical Aeroplane-"The critical aeroplane is a conceptual aeroplane whose characteristics are a composite of the most critical elements of all the aeroplanes that the facility is intended to service. For example, in the design of a runway the critical characteristic determining runway width may derive from a different actual aeroplane than the critical characteristic determining clearance to the parallel taxiway...

  It is the aerodrome operators' responsibility to determine the critical aeroplane for each aerodrome facility. This should be done in close consultation with users (airlines etc.,), and the CAA"[RPA1998,p7-2]

  If the airport managers have properly discharged these responsibilities, it should be a simple matter to describe the critical aeroplanes for the runways and taxiways. Why not ring them and ask for an answer ?

  Is the proper answer to this question, a 737-300 ? Dash 8-300 Hawker Siddeley 748 Gulfstream IV BAe146 B737-100 B737-200 B737-300 B727-200 Cessna 150 B757 B767

   

• Runway - A defined area provided for the take-off and landing of aeroplanes [RPA98,p7-11]...

  Should we ask, who defines the areas ? Is it by some order issued under a section of the act or regulations governed by it ?

   

• Instrument Runways - "A runway may also be referred to as being either an instrument runway, or a non-instrument runway. A non-instrument runway is intended only for the operation of aeroplanes using VFR (Visual Flight Rules) procedures".[RPA98,p7-11]

  Instrument runways are further classified into two types, non-precision approach runways, suitable for moderately poor weather, and precision approach runways for very poor weather[RPA98,p7-12].

  • Non-Precision Approach Runway - an instrument runway equipped with visual aids, and a radio aid providing at least directional guidance adequate for a straight-in approach.

    Non-Precision Approach Runways are typically served by visual aids such as T-VASIS, runway markings, and runway lights, and radio aids such as an NDB, VOR and DME. As from July 1998, Global Positioning System (GPS) aids were added to the list, and concessions made to allow their use on runways of less strip width than previously allowed for NPA runways.

  • Precision Approach Runway - there are three categories, for various types of aircraft. Essentially, precision approach provides height as well as directional guidance with the strictest category (IIIC) supporting landing in zero visibility conditions.

   

• Runway Strips - "A runway and any associated Stopways are to be centrally located within a runway strip. This is an area provided both to reduce the risk of damage to aircraft running off a runway and also to provide an obstacle-free airspace for aircraft flying over the area during take-off or landing operations. The runway strip, therefore, comprises a graded and obstacle free area specially prepared to minimize damage to aircraft should it run off the runway, and also to allow aircraft to fly over the area safely. The whole width of this runway strip is a graded area."[RPA98,p7-32]

  "The runway strip is to extend beyond the end of the runway or Stopway, if provided, for a distance of 30 m for code 1 runways and 60 m for code 2, 3 and 4 runways." [RPA98,p7-33]

  Has 11/29C, since 1996, become a code 3 runway - does the drain mean the strip length does not meet this requirement ? . Yes Other No See if you think the drain is closer than 30 m since the 1996 work. Yes Other No

   

• Runway Threshold - "the point on the ground from which the landing distance available to an airplane is measured. It's position on the ground is basically determined by the airspace requirements of the airplane and in particular the requirement for a landing aeroplane to be able to fly down an approach path that is completely free of obstacles.

  For a new runway, the beginning of the runway is normally made to coincide with the threshold. However, in exceptional cases where this would result in an inadequate runway length for takeoff (in the same direction), the beginning of the runway may need to be located prior to the threshold, as shown in the following diagrams" [RPA89,p7-13]. The Aerial photos indicate Bankstown is exceptional - they're really squeezing things in.

  The threshold is marked by a 1.2 m wide line extending the full width of the runway. Six (6) meters inside this line, there are then a series of 30 m long piano-key stripes, which appear as light grey rectangles in this photo due to their close spacing (there should be two sets of 8 stripes, each 1.5 m wide and 1.5 m apart with a central 3 m gap).

• Runway End Safety Area (RESA) - "areas of ground at each end of a runway, symmetrical about the extended runway center line, and abutting the end of the runway, or Stopway if provided. RESAs are provided to reduce the risk of damage to a landing aeroplane which touches down before the threshold, or to an aeroplane overrunning the end of a runway either during landing or in an aborted take-off." [RPA98,p7-38].

  "A RESA should be provided at each end of the runway, or Stopway if provided, for as great a distance as is practicable."

  "The minimum length of the RESA is to be 90 m where the associated runway is suitable for aircraft with a code number of 3 or 4" (i.e. Bankstown's 11/29C) "and is used by regular public transport jet aeroplanes" (also at Bankstown) [RPA98,p7-38].

  "In other cases, the minimum RESA length is automatically provided for by the requirement for the runway strip to extend beyond the end of a runway... Where provision of a RESA is not feasible due to terrain constraints or obstracles, consideration should be given to reducing some of the declared distances in order to meet the RESA requirements".[RPA98,p7-38]. The RESA width should be twice the width of the runway.

  As noted above, 11C/29C's strip does not provide the necessary 60 m graded area at the end. So should the drain's presence at Bankstown have prevented the increased declared runway lengths? Yes Other No

  USA's FAA standards require much longer RESA lengths. For precision instrument operation with small aircraft, 180 m is required, and for large aircraft in all design groups 300 m is needed [Horonjeff83, p395]. So don't think the Australian Standard is maybe too fussy and that airport managers could be excused for ignoring it.

   

• Clearway- "an obstruction free rectangular plane, extending from the end of a runway, over which an aeroplane taking off may make a portion of its initial climb to 35 feet (10.7 m) above the ground at the end of the Clearway.

  It is used to increase the take-off distance available (TODA) without increasing the length of the runway proper. Thus a Clearway is not prepared for the surface movement of aircraft, but only to be cleared of upstanding obstacles to permit safe overflying" [RPA98, p7-39]. Looks like drains can be in Clearways.

  "The Clearway commences at the end of the take-off run available (TORA ). A Clearway overlies part of the runway strip (e.g. that part not paved with runway), including any Stopway, if provided, and may overlap part or all of the runway safety areas.

  The declared length of the Clearway is not to exceed half the length of the TORA, i.e. the Clearway will be equal to or less than half the runway length." [RPA98, p7-39]

   

• Stopway,- "a rectangular area of ground, originating at the end of a runway, on which an aeroplane may be stopped in the case of an aborted take-off. A Stopway may be used to achieve the financial savings associated with lower strength pavement and the absence of runway marking and lighting.

  A Stopway is to finish at least 60 m before the end of the runway strip" [RPA98, p7-40]

  Note that 11C/29C at Bankstown does not even 15 m between the runway eastern (29C)end and the strip end! But when the drain is filled in, it will.

  "In considering the length required for a Stopway, it should be noted that this length is used by pilots as part of the calculations to determine the payload that can be uplifted from the runway"

  "A Stopway is to have the same width as the runway with which it is associated". So, prior to 1996, the pre-runways should not have been called Stopways - weren't they too narrow ?

   

• Pre-Runways- "the pre-runway marking is to be used where an area exceeding 60 m in length before the runway has a sealed, concrete or asphalt surface, and is not suitable for normal use by aircraft. This marking is to consist of yellow chevrons space 30 m apart"

  The area marked by the pre-runway end marking will not normally be used for landing or take-off. If this area is declared as a Stopway, it may only be used by an aircraft in the case of an abandoned take-off or from the other direction under emergency conditions" [RPA98, p11-4]

   

• Runway Width- " The appropriate runway width requirement may be determine by cross-reference to the Table of Width of Runways using the 'critical' aeroplane reference code. The runway width standards specified in the table are to be used for the construction of a new runway or the upgrading of an existing runway.
  Table of Width of Runways

  Code Number	Code Letter
  Code Number	A	B	C	D	E
  1	18m	18m	23m
  2	23m	23m	30m
  3	30m	30m	30m	45m
  4			45m	45m	45m

  "Aerodrome operators are advised that some aeroplanes may be permitted to operate from runways with width not in accordance with the Table of Width of Runways above under any one of the following circumstances:

  1. An aeroplane may be operated from a runway one width less than that specified in the Table of Width of Runways above provided [RPA98,p7-21]:
     1. it was manufactured in the USA and the Federal Aviation Administration aircraft design group permits a runway width narrower than provided by the Table of Width of Runways; or
     2. it has an aeroplane reference field length (AFRL) less than 1500 m and all flight manual crosswind limits are reduced by 50%.
  2. (omitted)
  3. The Authority has conducted runway width testing of an aeroplane and approved its operations at narrower runways
  4. (omitted)

  And in fact [RPA98, p7-30] 737-300's are certificated by the CAA to operate on 30 m wide runways (as if they were 3C category, like BAe 146's and Gulfstream IV's). They operate at Launceston, Maroochydore, and Hamilton Island all of which have only 30 m wide runways.

   

• Runway Lengths - "The length of a runway to be provided at an aerodrome is to be determined by the aerodrome operator. It should be adequate to meet the operational requirements of the crticial aeroplane, at the desired Maximum Take-Off Mass (MTOM) for which the runway is intended. The operational requirements of aeroplanes are normally determined by airlines or aeroplane operators, within the aeroplane mass and performance limitations set by CAA".

  Because of the "should be" terminology, this is only a recommendation. The runway length does not have to suit the Maximum possible take-off weight for an aircraft. An airport operator has the freedom to allow aircraft to operate, for instance, at weights lower than their maximum (if he/she were really concerned that the runways could take only 50 tons).

  Accordingly, the runway length should be determined in close consultation with the airlines and other aeroplane operators that the aerodrome operator wishes the aerodrome to accomodate, and the CAA, so that the desired maximum capacity may be obtained at the lowest cost.

  When arriving at the length of the runway required, the aeroplane operator will utilise data provided by the aeroplane manufacturer and certified by CAA. These data cover the following considerations:

  • the maximum take-off mass of the critical aeroplane
  • the maximum permissible landing mass of the critical aeroplane
  • the climb performance, and braking performance of the critical aeroplane
  • the longitudinal slope of the runway
  • the air temperature and density based on the location and elevation of the aerodrome
  • the wind velocity
  • the runway surface condition: wet or dry.

  Might we wonder who BAL have been consulting with in recent times ? Virgin Blue Qantas Horizon Hazelton Kendell Singapore Airlines One or more of above All Above

   

• Declared Runway Lengths - There are standard aviation terms to report runway lengths that are critical to aircraft performance - in determining the size and range of aircraft that can operate on a runway. There are four declared distances (CASA definitions in italics, taken from Publishing Aerodrome information and reporting changes, a Civil Aviation Advisory Publication, CAAP 89O-1(1), May 1997):

  • TORA- takeoff run available - "the length of runway declared available and suitable for the ground run of an aircraft on taking off. It will normally be the full length of the runway. Neither Stopway nor Clearway are involved." [CAA97, CAAP 89)-1(1), p17] [In most cases, this corresponds to the physical length of the runway pavement]

  • TODA - takeoff distance available - "defined at the distance available to an aeroplane for completion of its ground-run, lift-off and initial climb to 35 feet. It will normally be the full length of the runway plus the length of any Clearway. Where there is no designated Clearway, the part of the runway strip between the end of the runway and the runway strip end is included as part of the TODA. This Australian practice has been registered with ICAO. Any Stopway is not involved." [CAA97, CAAP 89)-1(1), p17]

    From Bob Tait's Aviation Theory School, VFT Study Guide p1.2.4, "the length of take-off run declared available, plus the length of any Clearway available. TORA plus length of any remaining runway and/or Clearway beyond the far end of the TORA. The take off distance allows for the aircraft to remain on the ground to the end of the TORA, and then climb to 50 ft (propeller aircraft) or 35 ft (jets). The Clearway surface may be totally unsuitable for aircraft to run over - it is provided for the unobstructued climb to 50 ft It does not consider transient obstacles such as trucks or buses which may be passing by.

  • ASDA - accelerate-stop-distance-available - "the length of the take-off run available plus the length of any Stopway. Any Clearwayis not involved." The Stopway is available for the deceleration of an airplane aborting a takeoff

  • LDA - landing distance available - "The length of the runway available for the ground run of a landing aeroplane. The LDA commences at the runway threshold. Neither Stopway nor Clearway are involved."

    Landing distances for aircraft are usually much smaller than take-off (no allowance need be made for aborted take-offs or engine failures).

    From the Jan 1998 and July 1998 ERSA :

    Table 1 - Jan 1998 ERSA Runway Dimensions

    RWY	TORA meters (feet)	TODA meters (feet)	ASDA meters (feet)	LDA meters (feet)
    11C	1415 (4642)	1475 (4839)	1415 (4642)	1260 (4134)
    29C	1415 (4642)	1415 (4642	1415 (4642)	1355 (4444)
    18	800 (2624)	860 (2820)	800 (2624)	800 (2624)
    36	800 (2624)	860 (2820)	800 (2624)	704 (2309)

     

   

• Enroute Supplement Australia (ERSA) - An Aeronautical Information Publication (AIP) published by Airservices Australia and widely distributed to pilots and airlines. It contains "aerodrome information of a lasting character, in two separate sections. The Facilities section sets out all the facilities available at an aerodrome. The Runway Distances Supplement Section sets out in detail runway declared distances information... The ERSA is updated quarterly" [CAAP 89O-1(1)97,p3]

  While trying to argue that no runway extensions had occurred and that ERSA distances were not evidence of these, A BAL manager once claimed "The En Route Supplement (ERSA) reports the effective operational lengths available at time to time and does not report the actual length of the strips". Don't buy it. The ERSA changes are of a lasting character. See NOTAM definition for the temporary changes.

  Additionally, the 1996 and 1997 FAC Annual Reports provide a listing of airport data (Appendix 11 of each). In 1996, it gives 11C/29C length as 1111 m and in 1997 as 1415m. These reports also show that two 18/36 runways (18L/36R at 476 m, 18R/36L at 796 m) become one 18/36 runway of length 860 m - it was the eastern-more 476 m length 18L/36R that survived, the other possibly a victim of obstacles soon to be build as part of the South Western Corner Developments.

  ERSA's have been made available (Sep 2003) at http://www.airservices.gov.au/pilotcentre/aip/ersa.htm

   

• Notices to Airmen (NOTAM) - "in relation to an aerodrome, advises pilots of changes in the serviceability of the aerodrome, usually with safety implications. They are designed for rapid promulgation."[CAAP 89O-1(1)97,p3].

  NOTAMS are available at Airservices site, http://www.airservices.gov.au/brief/fulltext.htm .

   

• Aeroplane Reference Field Length (ARFL) - the minimum field length required for take-off at maximum take-off weight, at sea level, in standard atmospheric conditions, in still air, and with zero runway slope. It is set out in the aeroplane flight manual. [RPA98, p7-6 to 7-10] gives some representative aircraft data for ARFL.

   

• Aerodrome Facility Reference Code (AFRC) - also known as reference code, this is a two element alpha-numeric notation (for example 1B, 2C) derived from the critical aeroplane for that aerodrome facility (facility meaning a runway, taxiway, apron, or other airport feature)

  The number part of the code is based on the Aeroplane Reference Field Length, (see above), as follows:

  Aeroplane Reference Field Length	Code Number
  Less than 800 m	1
  800 m up to but not including 1200 m	2
  1200 m up to but not including 1800 m	3
  1800 m and over	4

  The letter part of the code depends on the wing-span of the aeroplane, and its outer main gear wheel span as follows:

  Aerodrome Facility Reference Code Letter

  Wing Span	Outer Main Gear Wheel Span	Code Letter
  Up to but not including 15 m	Up to but not including 4.5 m	A
  15 m up to but not including 24 m	4.5 m up to but not including 6 m	B
  24 m up to but not including 36 m	6 m up to but not including 9 m	C
  36 m up to but not including 52 m	9 m up to but not including 14 m	D
  52 m up to but not including 65 m	9 m up to but not including 14 m	E
  65 m up to but not including 84 m	14 m up to but not including 20 m	F
  84 m up to but not including 95 m	14 m up to but not including 20 m	G

  Applying these tables, a 737-300 is a 4C aircraft, This means that is can operate off a 30 m wide runway (see Table of Widths ). All 727's are also 4C. A 707 is a 4D, but the Queen of England's Royal 707 has been to Bankstown. B757's and 767's are 4D.

  There are numerous ways (see [RPA98,p7-21]) that an aircraft can be matched with a lower rated runway. And in fact [RPA98, p7-30] 737-300's are certificated by the CAA to operate on 30 m wide runways (as if they were 3C category, like BAe 146's and Gulfstream IV's).

  As well, 737's and 767's operate at Maroochydore (Qld), which is less than 1800 m (it's 1797 m), Hamilton Island (Qld)(1764m), and Launceston (Tas) (1981 m) and all are only 30 m wide runways.

  Take-off charts for the 737 go down to runway lengths of just 1200 m - you wouldn't get much payload at that length (maybe 10 t in good weather), but as the length increases you will get increasing payload - at 1400 m about 14 t, at 1800 m about 17 t, until at 2073 m (its AFRL) you get maximum payload (20 t).

   

• Runway Strength - "A runway should be capable of withstanding the aeroplane traffic the runway is intended to serve. Although standards governing runway strength are not specified, the runway ... should be able to carry the wheel loads and frequency of movements of the critical aeroplane.

  Apart from extreme and therefore rare cases, aircraft safety is not an issue in the matter of runway pavement strength. By their nature, pavements deform rather than break, and even gross overload normally results in nothing more than rutting or deformation of the pavement. If left untreated this may lead to distress such as break-up of the surface with potential for ingestion of loose material in an engine, aeroplane controllability, acquaplaning and jet-engine flame-out problems." [RPA98, p7-28].

  What is an extreme and rare case ? Would a 767 landing at Bankstown in an emergency be such ? Or would it take several years operations ? Airport managers have said a "727 would go straight through the runway". Does that tally with this (and later material in Chapter 9 of Rules and Practices discussing pavement concessions) ?

   

• Runway Pavement Strength Data- "The aerodrome operator is to provide (in the Aerodrome Manual) runway pavement strength data for all runways. This information is to be provided in one of two ways: one for runways used only by light aircraft with maximum take-off mass (MTOM) not exceeding 5700 kg, and the other for runways used by heavy aircraft, with the MTOM exceeding 5700 kg"[RPA98,p9-26].

  For light aircraft pavements, the allowable maximum take-off mass (MTOM) in kilograms, and the maximum allowable tyre pressure in kilopascals is to be reported.

  For heavy aircraft pavements, "the aerodrome operator is to report pavement strength using the Aircraft Classification Number/Pavement Classification Number (ACN/PCN) system. This method uses five parameters to specify the strength of the pavement: the Pavement Classification Number, pavement type, strength of sub-grade, maximum allowable tyre pressure, and the method used in pavement evaluation.

  Bankstown's 11C/29C is in the heavy aircraft category.

  The Civil Aviation Advisory Publication CAAP 89O-1(1), May 1997, "Published aerodrome information and reporting changes" prescribes the manner of reporting data in ERSA. For the movement area data, it requires that it include "runway pavement strength rating under the ACN-PCN system".

  Bankstown's ERSA (as of July 1998) does not include that, but rather uses the light aircraft reporting method. Is this just an oversight, or are they trying to hide something ? Suspicious. Incompetent. Corrupt. Innocent.

Aerial Photo Edits

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