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CAO 100.5

100.5 Final Rule Making:

CASA again blame industry for it’s failures

CAO 100.5 nfrm1101cs



23rd Aug 2013, 08:53   #79 (permalink)
Join Date: May 2010
Location: More than 300km from SY, Australia
Posts: 437
casa and atsb just do not get it!!!!!!!!!

Here is casa’s NFRM for parts of 100.5. Note the changes where casa blames the industry. Where was casa in this, if the matter is so bad. There is no evidence I have seen which shows near misses in regulated airspace.

Oh, by the way, the last time that I looked, all aircraft have a pitot system!!

Final Rule Making

1. Background

1.1 The primary method used by pilots to monitor and maintain a desired altitude is with a barometric altimeter. It works by measuring ambient air pressure (static pressure) and providing a display to the pilot in units of height. These instruments, whether they are aneroid based or solid state, need to be checked on a regular basis to ensure that what is being presented to the pilot is accurate. This is particularly critical during approach and departures that have terrain obstacles in close proximity.
1.2 AD/INST/8 Amdt 4 and AD/INST/9 Amdt 6 formerly required either:

  • the pressure altimeter/s fitted to an aircraft are tested every two years in accordance with the nominated altimeter maintenance standard; or
  • all aircraft instruments and instrument systems are tested in accordance with specified requirements every three years.

1.3 Following correspondence from industry regarding those altimeter setting procedures, a review of those procedures exposed an indirectly related anomaly in published material regarding altimeter maintenance standards.

1.4 Conflicting maintenance standards that are defined for aircraft operating under the Visual Flight Rules (VFR) and Instrument Flight Rules (IFR) effectively allowed aircraft with altimeters maintained to different standards to operate in the same airspace which, in the worst case scenario, could result in a loss of separation between the two aircraft.

1.5 With the introduction of Wide Area Multilateration systems into the Sydney metropolitan area as well as large areas of Tasmania it is essential that accurate altitude information is broadcast, via the Mode C transponder, for Air Traffic Control purposes. This would apply to any aircraft transmitting Mode C information regardless of operation under either the VFR or IFR.

1.6 An unintended consequence of allowing a choice of actions within the Airworthiness Directives (ADs) had been the interpretation that, with opting to do the pressure altimeter check, other aircraft instruments and instrument systems did not have to be maintained. This may have resulted in the accuracy of critical aircraft instruments degrading.

This just points to a regulator that does not even have an awi system that works. There are lots of examples of this causing issues that casa just chooses to sweep under the carpet.