1. Scope

This Policy document outlines the Surveillance and Service Life Program to be undertaken by ASRI to ensure continued safe storage and use of the 3-inch Sighter and 5-inch Zuni rocket motors by the ASRI Small Sounding Rocket Program.

In January 1996, the then Minister for Finance approved the gifting of a quantity of approximately 600 Zuni rockets and 400 Sighter rockets to ASRI for use in educational and research programs. Subsequent to this gifting, the personnel from RAAF 1CAMD inspected the rockets and found that they do not meet the RAAF requirements for safe munitions. Consequently, the Australian Ordnance Council (AOC), now renamed the Ordnance Safety Group, within the Department of Defence was requested to provide a definitive statement of the safety of the motors and to provide a surveillance program that would allow the continued safe storage of the motors.

The AOC's response to this request can be found at Applicable Document AD2.1. It outlines the surveillance requirements for the continued safe storage of the motors. ASRI, as the new owners of the rocket motors, is responsible for undertaking this surveillance program to the satisfaction of the AOC and the requirements set out in AD2.1.

2. Applicable Documents

AD2.1 - 'Surveillance program for 5" Zuni and 3" Sighter rockets', Australian Ordnance Council letter AOC 409/98

AD2.2 - 'Motor, Rocket, Aircraft, 3-inch, No.1, Mk 4', AP 2802A (2nd Edition).

AD2.3 - DSTO Technical Report, DSTO-TR-0017, AR-008-648 of May 94.

AD2.4 - '5-inch ZUNI Rocket', S. A. Les Forges de Zeebrugge, Herstal.

3. Three Inch Sighter Rocket Surveillance Program

3.1 Description and Stocks

The Sighter rocket propellant grain is of the cartridge-loaded, double-base type. A general description of the 3-inch Sighter rockets is given in AD2.2. The propellant contains an Ethyl Centralite stabiliser, with the manufacturer's specification for the stabiliser level between 8.7% and 9.3%. Testing by DSTO in 1993 (AD2.3) revealed the level of Ethyl Centralite to be 8.3% which is only slightly below the manufacturer's specification.

The AOC subsequently advised ASRI (AD2.1, paragraph 3) that a '... report on the condition of the 3-inch Sighter rocket motors by DSTO concluded that the propellant grain was in good condition and recommended that the motors will remain safe until at least 1999'.. Based on the DSTO advice, the AOC authorised a life extension of 5 years to the Sighter motors. Table 1 lists the current stock details of ASRI's Sighter rockets, including percentage stabliser content at last test.

3.2 Propellant Chemical Testing

The AOC has specified (AD2.1) that until the stabiliser level reaches 6.5%, surveillance testing should be conducted at 5 yearly intervals. Once the stabiliser level drops below 6.5%, the testing period should be reduced to 2 yearly intervals. Once the stabiliser level drops to below 5%, the motors are to be considered unsafe for storage and destroyed. The sample size for testing, shall be one (1) motor from each propellant Lot. Table 2 summarises the Sighter propellant testing interval requirement.

Initial Sighter propellant stabiliser testing was conducted in November 1999 as shown in Table 1. Based on these test results, and the requirements listed in Table 2, ASRI will arrange for Sighter propellant testing to be conducted again in 2004.

3.3 Motor Ballistic Testing

In addition to the chemical stability of the Sighter rocket propellant, the AOC has requested that static testing of three (3) motors from each Lot be undertaken at pre-conditioned temperatures of -20, +25 and +60 degrees Celcius respectively, every two (2) years. The ballistic testing shall be limited to the measurement of the motor thrust vs time profile. Should the ballistic performance not meet the specification requirements, as given in AD2.3, then a further chemical stability analysis is to be conducted within six (6) months of the static firings.

4. Zuni Rocket Surveillance Program

4.1 Description and Stocks

The Zuni motor contains a cartridge-loaded, double-base propellant grain. A general motor description is provided in AD2.4. The propellant contains 2% stabiliser (2NDPA) at manufacture. The AOC advised ASRI (AD2.1, paragraph 7) that testing by DSTO conducted in 1996 revealed only slight reductions in the stabiliser level (of the order 0.02% to 0.08%) over a period of 20 years. Table 3 lists the current stock details of ASRI's Zuni rockets, including percentage stabliser content at last test.

4.2 Propellant Chemical Testing

The AOC have requested that a Zuni propellant sample from each Lot be chemically tested for the 2NDPA stabiliser level every 5 years until the 2NDPA level drops to 1.5%. Thereafter, the sampling period is to be reduced to 2 years until the stabiliser level drops to 1% at which point the motors are to be considered unsafe and destroyed. Table 4 summarises these requirements.

Zuni propellant stabiliser testing was conducted in December 1997 and again in November 1999, as shown in Table 3. Based on the latest test results, and the requirements listed in Table 4, ASRI will arrange for Zuni propellant testing to be conducted again in 2004.

4.3 Motor Ballistic Testing

In addition to the chemical stability of the Zuni rocket propellant, the AOC has requested that static testing of three (3) motors from each Lot be undertaken at pre-conditioned temperatures of -15, +25 and +40 degrees Celcius respectively, every two (2) years. The ballistic testing shall be limited to the measurement of the motor thrust vs time profile. Should the ballistic performance not meet the specification requirements, as given in AD2.3, then a further chemical stability analysis is to be conducted within six (6) months of the static firings.

5. Distribution of Results

The results of the chemical stability testing and the ballistic analysis for both the Sighter and Zuni rocket are to be kept on file in the ASRI Library and distributed to the following within one (1) month of the completion of the testing:

• Area Administrator, Woomera, Defence Support Centre Woomera, PO Box Woomera, SA 5720
  
• Director, Ordnance Safety Group, CP2-3-21, Department of Defence, Canberra, ACT 2600 (formerly the Australian Ordnance Council)

Policy Review and Approval

This ASRI policy was last reviewed internally in February 2002 and reaffirmed by the ASRI Board of Directors on 17 March 2002.