Commonwealth legislation

AD/G1159/29 - Flight Manual - Change to Metric Units

RepealedCTH

This Act has been repealed and is no longer in force. It is retained for historical reference.

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

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This safety directive requires owners and operators of Grumman G1159 series aircraft (Gulfstream II, III, and IV business jets) to rewrite their flight manuals—the handbooks pilots rely on for safe operation—using metric units instead of imperial measurements.

Specific changes required:

Aircraft weight limits must be listed in kilograms
Distances (such as runway requirements) in metres
Balance limits (centre of gravity) and related measurements in millimetres
Fuel and oil volumes in litres
Pressure readings in kilopascals

Exception: If the aircraft's cockpit instruments still display imperial units (such as pounds or gallons), the flight manual must show both metric and imperial figures side-by-side.

Deadline: Operators were required to comply by 1 January 1984.

This change ensured that all Australian aviation safety data used the national metric standard, reducing the risk of dangerous calculation errors caused by mixing measurement systems during flight planning or refuelling.

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Current sections

Direct links to the current provisions in AD/G1159/29 - Flight Manual - Change to Metric Units.

AD/G1159/29 - Flight Manual - Change to Metric Units

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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Gulfstream (Grumman) G1159 and G-IV Series Aeroplanes

AD/G1159/29 Flight Manual - Change to Metric Units 9/81

Applicability: All Grumman G1159 Series Aeroplanes.

Requirement: The D.o.T. approved flight manual shall be amended to specify quantities in the following units;

(a) weight in kilograms,

(b) distances in metres,

(c) centre of gravity limits and moment arms in millimetres,

(d) fuel and oil quantities in litres, and

(e) pressures in kilopascals.

Where the installed aircraft instrumentation is calibrated in units other than the above the flight manual shall specify both systems of units.

Compliance: By 1 January 1984.

Background: It is required that all Australian aircraft be provided with airworthiness limitations and operational data in the declared metric units.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/G1159/29 - Flight Manual - Change to Metric Units