Airworthiness directives as a central safety instrument
In the international air transport system, so-called airworthiness directives play a central role in the technical safety of aircraft. They are published whenever a potential safety problem is recognised for a particular aircraft type, engine, propeller or component.
Such problems can have different causes. In many cases, these are design weaknesses that are only recognised after a long period of operating experience. In other cases, material fatigue, faulty components or certain maintenance problems lead to safety-relevant findings.
If a corresponding risk is identified, the responsible aviation authority publishes an airworthiness directive. This contains binding specifications as to which measures must be carried out and within which deadlines this must be done. Typical measures may include additional inspections, replacement of certain components or structural modifications.
European regulations have changed the process
With the increasing harmonisation of European aviation regulation, the handling of airworthiness directives has also changed. The European Aviation Regulation, which today forms the central legal basis for the regulation of civil aviation in the European Union, is a key factor in this.
Since an amendment to the German operating regulations for aircraft in 2013, airworthiness directives issued by the European Aviation Safety Agency (EASA) also apply directly in Germany. This means that additional implementation or publication by the Federal Aviation Office is no longer necessary.
This used to be different. National authorities first had to transpose corresponding instructions into national law before they became binding for operators. This additional administrative level was removed with the reform.
Today, as soon as EASA publishes an Airworthiness Directive, it is automatically binding for affected aircraft in Germany.
Adoption of foreign airworthiness directives
In addition to its own instructions, EASA also adopts airworthiness directives from other aviation authorities. This mainly concerns types that were originally certified by authorities outside Europe, such as the US FAA or the British Civil Aviation Authority.
If such an instruction is officially adopted by EASA, it also automatically applies in the European legal area. This ensures that safety measures are implemented as uniformly as possible worldwide.
For operators, this means that they must not only inform themselves about European publications, but also about instructions that originate from other authorities and have been adopted by EASA.
Role of the Luftfahrt-Bundesamt
Although EASA instructions are directly applicable, the Federal Aviation Office continues to play an important role in the airworthiness monitoring system.
On the one hand, the LBA continues to publish information on new airworthiness directives in the so-called Nachrichten für Luftfahrer. However, these publications are for information purposes only and do not constitute an administrative act in their own right.
On the other hand, the LBA remains responsible for aircraft that are not subject to European regulations. This includes, for example, certain national aircraft categories or special types whose certification is not managed by EASA.
In such cases, the Federal Aviation Office can issue airworthiness directives itself. These are also published via the Notices to Airmen and are binding for the aircraft concerned.
In addition, the LBA reserves the right to order supplementary or deviating measures in the event of special safety problems, even if an EASA instruction already exists.
Publication and sources of information
The actual EASA airworthiness directives are published on the agency's website. There, operators and maintenance organisations can view the current status of the Airworthiness Directives at any time.
The German Federal Aviation Office also provides corresponding information online. A national reference number is often assigned to enable better allocation within the German documentation systems.
It is important to note that this national number is for information purposes only. The legally binding nature results exclusively from the original publication by EASA.
Urgent airworthiness directives
Special attention is paid to emergency airworthiness directives. These are particularly urgent airworthiness directives where there is an immediate safety risk.
In such cases, aircraft owners are also informed directly, often by post. However, the prerequisite for this is that the responsible authorities have up-to-date holder data.
Owners are therefore obliged to notify the Federal Aviation Office of any changes to their address without delay. This obligation arises from the Aviation Licensing Regulations and serves, among other things, to ensure that safety-relevant information can be delivered quickly.
Responsibility for implementation
Responsibility for the timely implementation of airworthiness directives lies in principle with the aircraft owner or operator.
Depending on the organisational structure, this task can also be performed by a so-called Continuing Airworthiness Management Organisation. Such organisations are professionally responsible for maintaining the airworthiness of an aircraft.
If a prescribed measure is not carried out within the specified period, the aircraft is automatically deemed unairworthy. It may no longer be operated in this condition.
It is then also not possible to issue or renew an airworthiness certificate.
Documentation obligations for operators
A central component of the system is the documentation of all airworthiness directives. An overview must be kept for each aircraft, showing the current status of all relevant airworthiness directives.
This overview must include all affected components, including engines, propellers and other important components.
Even airworthiness directives that ultimately turn out not to be applicable must be documented. In such cases, it is noted, for example, that the affected component or serial number is not present in the specific aircraft.
If an airworthiness directive is actually relevant, the implementation of the required measures must be documented. This includes the date, operating hours or, if applicable, the number of landings at the time of implementation.
Control by aviation authorities
Proper documentation can be checked by the responsible authorities at any time. This often takes place as part of so-called ACAM inspections.
These are programmes for monitoring the continuous airworthiness of aircraft. Among other things, inspectors check whether all relevant airworthiness directives have been correctly documented and implemented on time.
For operators who manage their airworthiness themselves and do not work with a specialised organisation, the Federal Aviation Office provides examples and instructions for maintaining such overviews on its website.
A complex but indispensable system
Even though airworthiness directives involve additional work for owners and operators, they form an essential part of the global aviation safety net.
Systematically analysing technical problems and quickly implementing appropriate measures ensures that security risks are identified and eliminated as early as possible.
The procedure, which is now harmonised throughout Europe, ensures that such measures can be implemented quickly and uniformly - regardless of the country in which an aircraft is operated.
Airworthiness directives thus make a decisive contribution to ensuring that civil aviation remains one of the safest transport systems in the world.
Source references:
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