Text: Alain Debras - Pictures: ASD-Belgian Defense & Coll Serge Van Heertum   sbap 2018


The concept of aviation safety was born the day man created the first flying machine to research and develop all methods to reduce the risks inherent in flight operations.
This material contains basic notions relating to any human activity but also induces the incorporation of factors specific to the aerial activities.
According to the International Civil Aviation Organization (ICAO), "air safety is the product of all measures to reduce airborne risk. In pursuit of this objective, ICAO issues standards and recommendations that are applicable in the signatory countries of the Chicago Convention ".
Air "safety" should not be confused with air "security" which includes all measures taken to combat intentional malicious acts such as acts of terrorism. Aviation security consists mainly in searching for any explosive devices that may be unlawfully introduced on board civil aircraft, in any way whatsoever (in a checked baggage bag, a piece of hand baggage, via the transported cargo in bunkers, introduction by a crew member or a mechanic, sabotage, etc.). It also aims to prevent the carriage of weapons of all kinds in the cabin and cockpit of the aircraft (on people and in hand luggage), weapons that could be used for purposes of air piracy. This is what is commonly referred to as "airport security".
The main risk factors that are listed by the ICAO are:
- lightning that can hit an airplane in flight and damage its electrical or electronic systems
- bird hazard - collision with birds - especially if the volatiles are ingested by the reactors
- technical breakdowns (engine, flight controls, electricity, electronics, hydraulics, radio ...)
- structural fatigue following the compression and decompression phases to which the airplane is subject
- stalling in flight due to abnormal manoeuvres or errors in the measurement of the instruments on board
- any fire taking into account the quantities of fuel carried
- human factors because many accidents have said multifactorial (the cause is due to several people, who have committed a combination of errors causing accident).
In summary, safety is the key word of any aerial activity.
And this is especially true in a military environment where the presence of weapons adds to the risks for personnel and machines.
Accident prevention is therefore a constant struggle, one of the essential tasks entrusted by the Air Component to the Aviation Safety Directorate (ASD).
ASD is the Defense competency center for aviation safety.
Its scope covers air activities, aircraft implementation and maintenance, air traffic control management and avian risk prevention.


Prevention of air accidents

"It was in 1952 that the Air Force ensures the prevention of aviation accidents by ensuring the establishment of means to prevent them. The ASD works in the areas of flight activities, aircraft implementation and maintenance, airspace control management and wildlife risk prevention. Its constant concern is to train, educate and inform staff at all levels on all aspects of aviation safety to minimize risks. Following the closure of the King Albert I district in Evere, the ASD took possession of its new infrastructure in Beauvechain in June 2004."

Aircraft Accident Investigation

"Since 1947, a department is responsible for the investigation of military aircraft accidents. In 1957, the Aviation Accident Investigation Service (SEAA) was created. From this date, the surveys systematically integrate the technical and operational aspects. In 1993, the separate and independent services of investigation and prevention merged. Since then, the SEAA is an ad hoc service that is activated by order of the Chief Of Defense (CHOD). The investigation is conducted by a commission constituted by the staff of the ASD and by external persons deemed necessary for its smooth running. Since 2009, the ASD has been able to mobilize its expertise and resources for the benefit of the nation as part of the memorandum of understanding with the Directorate General of Air Transport of the Federal Public Service Mobility and Transport."

NB: The SEAA has been named ASIB for the Aviation Safety Investigation Board which is activated during a Category A accident and is dissolved at the end of its work.


Functionally and to ensure maximum independence and objectivity, the ASD is directly attached to the Commander of the Air Component.
The Aviation Safety Investigation Board (ASIB), activated when an accident occurs, reports directly to the Chief of Defense.

 (ASD-Belgian Defense )

The ASD is housed in modern premises within the Beauvechain air base; these consist of a block of offices (administration, laboratory, classrooms) and a large hangar to dispose and analyze the elements of the damaged devices and the intervention equipment (vehicles, tools etc.) ...); it is also equipped with large secure cabinets where are stored all the archives of services since their creation.
Right next to these buildings, the ASD also has secure ground where can be stored after investigations and analyzes the parts to remain available for additional investigations or at the request of the judicial authorities.
The ASD currently has 25 staff (out of 28 posts planned).
Around the Commander (an engineer aviator colonel) we find three groups:
- the Secretary
- the BSI (Office Synthesis and Investigation)
- the operational department composed of six sections:
           . Training Office (Marchetti - AlphaJet)
           . Heli and UAV Office (Alouette III - Agusta A109 - Seaking - NH90)
           . Combat Office (F16)
           . Transport Office (C130 - Embraer - Falcon - Airbus)
           . Human Factor Office (psychology - individual perception)
           . Air Traffic Management Office (including the Bird Collision Section - Avian Collision Prevention)
Each office is commanded by an officer belonging to the aircrew, assisted by a technical NCO.

  (ASD-Belgian Defense )

In its mission of prevention, the ASD regularly publishes the Safe Tea Time, a publication intended for the units.
It regularly organizes courses for aircrew and non-flying technicians.
The ASD aviation safety network is complemented by WASOs, TASOs and SASOs, which are located in the Air Component's operational units; these are attached both to their unit and also to the ASD to which they report.
    - Wing Aviation Safety Officer (WASO) is the unit air safety officer (Wing) who is attached to Wing Commander
    - TASO (Technical Aviation Safety Officer) is the air safety officer attached to the Senior Technical Officer
    - SASO (Squadron Aviation Safety Officer) is the air safety officer attached to the Flight Squadron Commander (one per squadron)
    - They are also supported by a BCU officer (Bird Collision Unit) and an ATSO (Air Traffic Safety Officer) responsible for air traffic safety.
These officers are alert to incidents reported to them, provide feedback to staff, and report to the ASD at the Wing level, Maintenance, Flying Squadron and Control Tower.

The three missions of the ASD are:
    - accident prevention
    - the management of aviation safety
    - the completion of post-crash investigations


This is obviously the essential mission that also involves all players in the Air Component.
Air safety is a state of mind that must prevail for everyone in the performance of their daily tasks because all, even the most basic at first glance, can have consequences for the safety of personnel, equipment and military infrastructure, but also civil.
Prevention must cover all aspects of all tasks because the occurrence of an accident is almost always the accumulation of a series of small mistakes that take separately do not seem to be of great importance.
The analysis of the phenomena is represented by the "Swiss Cheese Model".
In order to arrive at a fatal fault, the various systems of organization and control must have a flaw and the combination of several flaws must go on, in addition to the organization, prevention, action and control procedures.

  (ASD-Belgian Defense )

Prevention also requires a complete reporting system that makes it possible to be informed of all the situations that led to an incident in flight, on the ground, during air traffic control; each report must be investigated and then will be the basis for writing recommendations.
This requires that everyone be honest and participate in the reporting of all daily events without fear but with the aim of contributing to the collection of information.
Thus the possible consequences are reduced, the sources of minor or serious injuries are reduced and the fatal consequences are reduced or avoided.

"The Air Force is a bunch of honest people; sometimes they make mistakes".
"An error is an opportunity to make the system better".
 ( ASD-Belgian Defense )

The main subject of prevention has become the human factor.
Over time, technical qualities and flight control technology have resulted in greater aircraft reliability and technical causes have been steadily decreasing.

  ( ASD-Belgian Defense )

The attrition factor increased from 2.92 / 10,000 flight hours in 1951-60 to 0.24 / 10,000 flight hours in 2001-10.
And in recent years, it is still down to its lowest level of all time = 0.12 / 10,000 flying hours in 2015.
If we exclude voluntary (criminal) acts, the factors of human error are of several types:
    - active error in the context of the function
    - latent error caused by an external factor
The fault can come from a bad execution of a correct procedure or the choice of a bad procedure well executed but badly adapted to the situation.
And always there is a chain of events that contribute to the fatal outcome: lack of organization, supervision, procedure and human error.
Prevention serves to break this chain of human errors.
One always returns to the human error, because whatever his level of intervention, the man is always at the source since he develops the models of planes, constructs them, pilot them and manages the operating systems !
The main factors of human error are:
    - tiredness
    - stress
    - effects of food (alcohol, pharmaceuticals, drugs)
    - decreases in sensory qualities (sight, hearing)
    - distraction and lack of concentration
    - overconfidence
    - lack of studies
    - personality
    - decision process, storage and data management
    - lack in communication
    - teamwork, leadership

The ASD organizes specialized courses addressed on a case-by-case basis to all categories of staff with the aim of inculcating basic rules of safety and good behaviour; promote safety culture.
There is always insisted on the need to participate in an honest reporting of all dangerous situations, even minor incidents at all levels of function.


The Safety Management System (SMS) is the aviation safety management structure used by the ASD for prevention.

    - Safety Policy and Objectives
          1. Management commitment and responsibility
          2. Safety accountabilities
          3. Appointment of key safety personnel
          4. Coordination of emergency response planning
          5. SMS documentation
    - Safety Risk Management
          6. Hazard identification
          7. Risk assessment and mitigation
    - Safety Assurance
          8. Safety Performance monitoring and measurement
          9. The management of change
          10. Continuous improvement of the SMS
    - Safety Promotion
          11. Training and education
          12. Safety Communication

One of the major difficulties in this management is the balance to be found between the search for the maximum factors of safety and operability of the units.

  ( ASD-Belgian Defense )

In this context, the ASD regularly organizes a "survey", a sort of audit of the level of security within the units, and makes recommendations based on the information gathered.


The final mission of the ASD is the rapid response at the scene of an air accident to take all security measures to protect the site, preserve the premises and the clues that can be used for the investigation.
At the occurrence of a serious accident, in Belgium or abroad, the Aviation Safety Investigation Board (ASIB) is constituted and will take responsibility for the intervention and the investigation under the sole authority CHOD (Chief Of Defense) which constitutes a commission of inquiry.
This is directed by the officer who commands the Synthesis and Investigation Office, assisted by an Ops officer, a technical officer, a doctor, the Human Factors officer and additional experts as appropriate.
The ASIB has:
    - 17 technicians investigators (Ops, Tech and ATM)
    - callable within two hours 24/7
    - 5 vehicles
    - a workshop trailer with intervention equipment, tools and protective equipment
    - possibility of transport by road or by air (depending on distance and speed of intervention)
    - ASTRID communication system (liaison with police, civil rescue, authorities ...)
    - measurement and detection equipment
    - an investigation shed
The intervention on the site takes place as soon as possible after emergency intervention (firefighters, medical services, police, civil protection) according to pre-established intervention plans (Internal Emergency Plan) taking into account the circumstances of the emergency, the accident, as to its location, the dangers, with or without aircraft, with or without a victim, with or without damage to non-military installations, with or without the involvement of local authorities, etc.
The speed of intervention is essential, especially if the accident aircraft is armed or presents specific risks.
It is necessary to quickly secure the site, on which are usually present the police, firefighters and other emergency services.
In all cases of intervention, the tasks are:
    - performing necessary SAR (Search And Rescue)
    - protect and help people
    - guarding aircraft/wreckage zone
    - limit and repair environmental damage
    - support judicial and aviation safety investigation

  ( ASD-Belgian Defense )

The origin of hazards in the area is sometimes difficult to manage when arriving at the scene; the main factors may be a combination of fuels and oils, armaments, explosives and ammunition, hydrazine (F16), various vapors and toxic gases, pressurized containers, oxygen tanks, fire extinguishers, carbon fiber parts and debris, biological or chemical radiation ...
After the red zone has been released, the ASIB function can begin.
Photographs, including aerial, are taken, the position of the controls and switches in the cockpit can already provide valuable indications.
The different debris is listed and their GPS coordinates are encoded and crew members and/or witnesses are also interviewed.
At the end of this preliminary investigation, the wreckage and debris are removed and taken to the ASD premises in Beauvechain where the investigation of the circumstances and causes of the accident begins.

  ( ASD-Belgian Defense )

Specialists scrutinize a maximum of parts in a work of great precision to list all the indices likely to advance the investigation.
The condition of the filament of a cockpit bulb, the position of a switch, a mark on a mechanical part, a deformation of a hydraulic cylinder, excessive wear, a trace of friction, a molten electric cable, everything is examined and nothing is left to chance.
The ASIB conducts its investigation independently, in parallel with the judicial inquiry and the administrative investigation, focusing only on the causes of the accident and not on individual responsibilities, and at the end of the investigation, it provides ASD and CHOD with a definitive report containing its conclusions and recommendations.
Relevant information may be communicated to other air forces equipped with the same type of equipment, and the ASIB is deactivated.

  ( ASD-Belgian Defense )

The investigation in the broad sense is a multidisciplinary work combining the skills of the investigation board, operations analysts, technical analysts, human factors analysts and photographers.
The report that is prepared by the ASIB will allow to build a multi causation model that lists all the circumstances and causes of the accident which will make it possible to issue the recommendations to improve the security conditions in the future.
The judicial investigation will focus on the responsibilities, faults and/or offenses with possible prosecutions at the Prosecutor's Office.
The administrative investigation will determine the material liabilities and will proceed to the reparation of the material damages as well as the possible disciplinary measures against the personnel.



One of the major risks of all the others is the collision with birds which can intervene at all times but whose gravity is the most important when it occurs at low altitude, in particular during the phases of take-off and/or landing.
The academic ornithological societies and the Meteo Wing of the Air Component provide them with permanent support.
Bird prevention is also supported by radar surveys carried out continuously in collaboration with the Royal Meteorological Institute (Jabbeke and Wideumont centers) and with Belgocontrol in Zaventem.
Messages are sent to the operational units to warn of migrations of birds or particular movements of certain breeds of birds which are found on the screens covering Belgium and the neighbouring areas.
To ensure the optimal management of this risk, a Wildlife Hazard Management structure has been set up within the ASD; it is organized in the Bird Control Section (BCS) and has local sections within operational Wings (consisting of three people = one officer and two collaborators).
On the bases, a series of means of action are set up and maintained permanently to repel the presence of wild animals and birds in particular (barriers, traps, gas cannons, rockets, sound emissions, balloons, ...) .

  ( ASD-Belgian Defense )
  ( ASD-Belgian Defense )
  ( ASD-Belgian Defense )
  ( ASD-Belgian Defense )
  ( ASD-Belgian Defense )  (ASD-Belgian Defense )
  ( ASD-Belgian Defense )  (ASD-Belgian Defense )
  ( ASD-Belgian Defense )  (ASD-Belgian Defense )
  ( ASD-Belgian Defense )  (ASD-Belgian Defense )
  ( ASD-Belgian Defense )  (Coll Serge Van Heertum) )
  ( ASD-Belgian Defense )  (ASD-Belgian Defense )

Finally, SBAP would like to thank Colonel Goffin - Commander ASD - for the quality of his welcome and the visit he has allowed us to make.


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