Questions and comments on Cessna SIDs
Why is there a SIDS program?
Typical general aviation aircraft from the 1950s to the 1980s were built to certification standards that did not consider what is known today about fatigue and been incorporated in aircraft designs since the late 1980s. These aircraft were typically designed and manufactured to fly safely and economically for about 20 years, given reasonable assumptions about usage and maintenance. The average age of these aircraft is now 40 years.
To keep these aircraft flying at more than twice their design life requires a detailed commitment to maintenance and inspection. Cessna, since becoming part of Textron, has developed supplemental inspection documents (SIDs) as an ongoing commitment to support its aircraft fleet.
Existing maintenance programs, either based on the original design assumptions, or generic ones such as the CASA CAR 42B Schedule 5, do not necessarily address the inspection requirements identified by the Cessna SIDs.
How was the SIDS program developed?
The Cessna SIDs were developed using a combination of modern engineering analysis techniques, worldwide in-service data and defect reports collected by Cessna over decades. The SIDs identified areas of the aircraft that are most likely to experience a principal structural element component failure under extended life operation. CASA has received more than 100 service difficulty reports (SDRs) on damaged structures, from organisations performing SIDs inspections.
Why do I have to undertake the SIDs program?
The requirement to undertake the SIDs is as a result of Civil Aviation Regulation 1988 (CAR) 42V. This requires registered operators to ensure that maintenance is carried out in accordance with the applicable provisions of the aircraft’s approved maintenance data. The Cessna SIDs represents such approved maintenance data under CAR 2A(2)(c).
I have a relatively new Cessna; do I still have to comply with the SIDs?
It depends on when it was made, the hours it has flown and its maintenance program. The Cessna maintenance program for newer models has SIDs embedded. The CAR 42B Schedule 5 often used for older Cessna models does not. However, the SIDs cover all Cessna aircraft.
My aircraft is thoroughly examined every 100 flight hours, and passes as airworthy. Why does it need further SIDs inspections?
SIDs inspections involve a far greater level of disassembly and inspection than that typically undertaken during 100 hourly/12 monthly inspections.
In some circumstances, on some aircraft, some areas that are difficult to reach can be inspected using modern techniques. If you want to put forward an alternative inspection technique to the SIDs, you can make an application to CASA using the process described in AWB 02-048.
Does CASA have any idea of the cost of these new regulations?
Anecdotal reports are that the SIDs inspection costs up to $20,000, plus any rectification that may be required to restore airworthiness.
Why does it cost so much to comply with the SIDs?
The cost of SIDs inspections is different for each aircraft series. Importantly, there are two potential cost components: the inspection costs and the rectification of any ensuing damage repair costs.
While the SIDs inspection costs are likely to be relatively standard across the industry i.e. typically involving a minimum of 80 hours, the ensuring rectification costs of any damage found will vary for each aircraft and can be significant depending on the life history of each individual aircraft.
Why have SIDs when there are hundreds of Cessna aircraft flying in Australia with no history of wings or other parts detaching in flight?
Just how many failures would be appropriate before a SIDs program was introduced? Would non-fatal accidents count, or would people have to die? There have already been a number of unambiguous age-related failures that were followed by lucky escapes. It would be foolish to ignore these warnings.
Consider this event involving a Cessna 210N, VH-JHF, near Bourke NSW on 12 September 2011. The pilot reported severe elevator control input difficulties, which an ATSB investigation found resulted directly from the fracture of the aircraft’s two horizontal stabiliser rear attachment brackets. The forward spar of the horizontal stabiliser was also extensively cracked, consistent, like the fractures, with metal fatigue. The damaged area was the subject of a Cessna SIDs inspection requirement which had not been undertaken.
We have heard that Cessna brought out these SIDs to avoid the possibility of litigation after an accident – is this correct?
Cessna’s current product liability in the United States is limited only to those aircraft up to 17 years old. The average age of the Cessna fleet in Australia is 40 years. Moreover, the ageing issues addressed by the SIDs apply equally to every aircraft type and are not unique to Cessnas.
For a government department to arbitrarily impose these charges on owners of private property is completely undemocratic and flies in the face of the freedoms that this country holds dear.
With freedom comes responsibility. CASA is responsible for the safety of the Australian public with respect to aviation. This applies both to people travelling in the air, as well as those on the ground. It has always been your responsibility to make sure your aircraft is flown safely and maintained safely. This is not a new change to civil aviation regulation. Under Civil Aviation Regulation 1988 (CAR) 42V registered operators must ensure that maintenance is carried out in accordance with the applicable provisions of the aircraft’s approved maintenance data. The Cessna SIDs represents approved maintenance data (under CAR 2A(2)(c)).
Why doesn’t CASA make the SIDs advisory?
The law says the SIDs program is mandatory. The aviation ruling of 2014 clarified that the SIDs is required under the existing legislation.
Of the 15,126 aircraft on the Australian register, how many are Cessnas?
Are SIDs programs going to be implemented in future for other types?
The requirement to comply with CAR 42V applies to all aircraft types. When another manufacturer develops a SIDs program, CASA is likely to require the application of that program.
Beechcraft, which is now owned by Cessna’s parent company, Textron, is in the process of developing SIDs for Bonanza models. CASA is also in discussions with Piper on the subject of SIDs for Piper aircraft types.
Is CASA trying to remove older aircraft from the register?
No. CASA is in no way seeking to remove older aircraft from the Australian register. CASA fully supports the continued operation of ageing aircraft in Australia, as long as it can be done safely.
When were Cessna aircraft owners advised in writing of the proposed regulations and the implications of the changes?
- The requirement to conduct SIDs inspections under CAR 42V has been in place since 1988.
- Further advisory material in the form of AWB 02-048 issue 1 - Compliance with Cessna SIDs – was published on 10 April 2014.
- This was clarified by Aviation Ruling 01/2014 which became effective on 14 April 2014.
- A revised AWB 02-048 Issue 2 was published on 7 April 2015.
- AWB 02-048 Issue 3 was published on 30 June 2015.
- AWB 02-048 Issue 4 was published on 22 December 2015.
Most private pilots fly fewer than 50 hours per year. I feel the current inspection is sufficient.
If you owned your aircraft from new, have always maintained it according to manufacturer’s data, stored it away from strong sunlight, salt and humidity in an animal-free hangar, and flew a modest 50 hours annually, then a SIDs inspection might find few, if any, substantial problems.
But if your aircraft previously belonged to someone else—as most ageing aircraft have—then you might end up paying the price for their maintenance shortcomings. You may have always cared for your aircraft, but damage to its principal structural elements may already have been done. This may even have happened at the time of its manufacture, through poorly applied corrosion treatments or seals. Without thorough inspections, this damage is likely to get worse.
What other countries require SIDs?
The US Federal Aviation Regulations (FARs) differ from the Civil Aviation Regulations, and as a result, SIDs are not required to be incorporated for aircraft in private operations, but are required for those aircraft in commercial operations.
Countries in addition to Australia that do require SIDs to be incorporated in all aircraft include:
- New Zealand
- Czech Republic
Countries that require partial incorporation of SIDs include: