Designing an aerodrome that complies with the Annex 14 and PANS-OPS limitation rules on obstacle surfaces can be a complex – and potentially very expensive – exercise, especially near big cities or in mountainous regions. Even less-populated areas can present problems with electricity masts or wind turbines nearby, for example. In such cases, an aeronautical study could literally save money.
Incorrect assumptions or calculations can result in unnecessarily costly outcomes.
Obstacle safety
An aeronautical study, or obstacle safety study as it is sometimes called, is generally seen as an extra expense when designing an aerodrome. It is “complex”, “difficult”, “expensive,” and an “imposed inconvenience” when the requirements of the ICAO Annex 14 cannot be met directly.
It is, of course, extremely important for the safety considerations of the airport operations. Developers must show how the airport will still be able to operate safely when there are nearby obstacles, such as buildings, chimneys, antenna towers and other masts, storage tanks, or wind turbines, that don’t comply with the Annex 14 standards. But sometimes the outcome can also prescribe solutions that are much less extensive than anticipated.
The benefits of aeronautical studies
This was the case with a recent aeronautical study we performed for an airport. Contractors were expecting to need a large portion of the construction budget to move or lower the numerous electricity towers in the area. As a result of the study, the number of towers penetrating the obstacle surface needing modification was reduced from several dozen to just three. In this case, the cost of performing an aeronautical study was negligible compared to the budgeted investment that could now be saved.
Despite the restrictive safety standards for obstacle limitation surfaces, the reality is that existing buildings and other objects frequently exceed those limitations. If the impact on safety and capacity can be minimised with operational measures, this may still be acceptable for both the airport and regulatory authorities. A properly detailed aeronautical study includes suggestions for mitigative measures that could be taken against the potential safety hazards.
Supporting the arguments
Naturally, the outcome of this aeronautical study example was a huge relief for the airport. It also underscores the need for in-depth knowledge, expertise and experience with the complexity of an aeronautical study. Incorrect assumptions or calculations can result in unnecessarily costly outcomes, as this example clearly shows.
We were also able to deliver a report that includes clearly the motivation for the findings that the client can provide to the relevant authorities to support their arguments for an exception request. One important advantage of this for clients is that it means they always have the right kind of information at hand to easily answer questions and information requests from the various authorities.
About To70. To70 is one of the world’s leading aviation consultancies, founded in the Netherlands with offices in Europe, Australia, Asia, and Latin America. To70 believes that society’s growing demand for transport and mobility can be met in a safe, efficient, environmentally friendly and economically viable manner. To achieve this, policy and business decisions have to be based on objective information. With our diverse team of specialists and generalists to70 provides pragmatic solutions and expert advice, based on high-quality data-driven analyses. For more information, please refer to www.to70.com.