Technical Airworthiness - What's that About?

Most of us are familiar with the broad organisational structure that governs aviation in New Zealand. We have the New Zealand Civil Aviation Act 1990 which provides the legal basis for the Civil Aviation Authority, under the Minister of Civil Aviation, to produce rules and regulations to implement and manage airworthiness of civil aircraft operating in New Zealand. These are the rules and regulations that the airlines, maintenance and repair organisations, pilots and generally anyone having anything to do with non-military aviation are required to follow.

The Civil Aviation Act specifically excludes the New Zealand Defence Force for most things as we have an operational need to do things that are frowned upon in civil aviation like close formation flying, flying at night with no lights on, dropping things that explode and so on.

So – as we are generally not covered by CAA rules that means we can pretty much do as we like right? Not so grasshopper – pull up a sandbag and I’ll give you the 411.

By definition military aviation sometimes is a bit more risky than civil aviation; flying into a region knowing that people might be trying to shoot you down is not very attractive to Commercial operators and their insurance underwriters. This does not mean we go and do things without thought, but rather that we make informed decisions on what is and what is not an acceptable risk. Clearly in times of no conflict or emergency the level of risk we as a military aviation organisation are prepared to accept is lower than those times when the mission dictates that a higher risk be taken. In order to assess these risks however we need a robust airworthiness organisation.

The Defence Act 1990 charges the Chief of Defence Force with the responsibility for ‘efficient, effective and economical management of the activities and resources of the Defence Force’. 

DFO92 – Defence Force Orders for Airworthiness is the prime document that outlines the airworthiness framework to be adopted by the NZDF, and while it is not about to win any literary awards for best thriller, it IS a great reference document. DFO 92 appoints Chief of Air Force as the NZDF Airworthiness Authority. To draw parallels with the civil aviation world you can think of CDF as the equivalent of the Minister of Civil Aviation, and CAF as the equivalent of the Director of the NZ Civil Aviation Authority. It is important to note that CAF is the airworthiness authority for ALL aviation within the NZDF; not only the RNZAF but the RNZN and Army as well – so anything that flies within NZDF comes under CAF in terms of airworthiness.

So what’s this airworthiness thing then? Well, it’s more than something as simple as ‘fit for flight’ like an aviation equivalent of a car warrant of fitness. It’s something bigger than that. The accepted definition is:

‘Airworthiness is a concept, the application of which defines the condition of an aircraft and supplies the basis for judgement of the suitability for flight of that aircraft, in that it has been designed, constructed, maintained and is expected to be operated to approved standards and limitations, by competent and approved individuals, who are acting as members of an approved organisation and whose work is both certified as correct and accepted on behalf of the New Zealand Defence Force.’

Whew –heady stuff! But some words that leap out of this definition are designed, constructed, maintained, operated, and competent. Airworthiness can be split into two broad arms – operational airworthiness and technical air worthiness. Now we’re getting somewhere!

Operational Airworthiness covers the actual use of the aircraft – how it’s flown, and by whom, which is where the operating competency bit comes in. CAF has delegated responsibility for Operational Airworthiness to the Air Component Commander, who in turn hands off the day-to-day management of operational airworthiness to OC 485Wing. How this is done, is a topic for a future article.

Technical airworthiness covers the design, build, maintenance and support of aircraft. This is where I come in. Just as CAF has delegated responsibility for Operational Air worthiness to the ACC, he has delegated responsibility for technical airworthiness to me, Commander of Air Force Logistics Group (CLG(F)).

What this means is that for every aircraft/ aviation platform in service in the NZDF, or about to enter service, team Logistics is required to ensure that the aircraft has been designed to appropriate standards by people qualified to do so; the aircraft has been built in accordance with the design from appropriate materials to an appropriate standard by people who know what they are doing; and the aircraft has been tested on the ground and in the air to confirm that it does what it was designed to do. We then need to check that we have all the information required to keep the aircraft airworthy – i.e. all the maintenance publications and so on; what are referred to collectively as ‘instructions for continued airworthiness’ so we can make sure that we keep the aircraft up to a standard that will ensure it remains airworthy.

Books and drawings are all well and good – but they are only as good as the people using them so we also need to make sure that the personnel who are going to work on the aircraft are given the right training and equipment to carry out the tasks listed in the maintenance manuals.

In addition to all this, we need to make sure that the spare parts we purchase to repair and maintain the aircraft are manufactured by approved manufacturers and sold by approved vendors so that we don’t end up fitting the wrong or unsafe parts to our aircraft.

A key component of this configuration management requirement is our computerised maintenance management system (CMMS), which until recently was the Air Logistics Information System (ALIS) but is now covered by the Plant Maintenance (PM) module of the NSDF corporate IT system SAP, delivered under the Joint Engineering Management System (JEMS) project. SAP now ties up engineering and maintenance data with supply and financial information to give us the whole picture.

As you can imagine, this is not a small task. Indeed a large part of my organisation is dedicated to making sure our aircraft are technically airworthy, and that technical airworthiness is maintained as we repair, maintain or modify our aircraft.

So – now that you know that there IS in fact a set of rules and regulations looking after the airworthiness of our aircraft, similar to those in the civil sector – sit back, relax, and enjoy your flight!

‘Technical Airworthiness covers the design, build, maintenance and support of aircraft’.