In aircraft maintenance, tool care is often seen as housekeeping: something done at the end of a shift, once the “real” work is finished. That view is misleading. A forgotten wrench, a contaminated rag or a tool left inside an engine nacelle can compromise an aircraft as much as a poorly executed repair.
For any aircraft maintenance technician, tool control is part of the maintenance process itself. Understanding why, and which practices the most demanding organizations apply, is part of becoming an aviation professional.
What FOD is and why it costs the industry billions
FOD (Foreign Object Debris) is any object or debris left in an aircraft during manufacturing or maintenance that does not belong there: tools, fasteners, safety wire, rags and even personal items. When that object damages a system or degrades its performance, it becomes Foreign Object Damage.
According to industry estimates cited by Boeing, FOD costs the aerospace sector between $3 and $4 billion every year. Behind that figure are damaged engines, grounded aircraft and operational delays, and much of it can be prevented through discipline in the hangar.
Tool control: a safety system, not a habit
That is why many maintenance organizations apply formal tool control systems. The best known is the shadow board: each tool has a space cut to its exact shape, so any missing item is detected immediately.
Another common method is the tool check system. Technicians receive one check for each tool they will use and leave it in the tool’s place when they take it out. At the end of the task, tools and checks must balance. The principle is simple: whatever goes onto the aircraft must come back.
Tool cleanliness: much more than appearance
Some aircraft systems are particularly sensitive to contamination, and oxygen systems are the clearest example. According to Airbus safety guidance, contact between high-concentration oxygen and hydrocarbons such as oil or grease can create fire and explosion hazards, even at ambient temperature and without sparks.
For this reason, manufacturer guidance states that tools, rags, clothing and hands must be clean and free from oil and grease when working on oxygen components. Components and surrounding areas should be cleaned with approved products before and after any work, and only lubricants specifically approved for the system should be used. In this context, a cleaning habit that seems minor becomes a safety barrier.
Best practices on the hangar floor
Organizations with mature FOD prevention programs share a set of practices that any technician can apply in their daily work.
Clean the work area after each task or operation, not only at the end of the shift, so that nothing carries over from one job to the next. Secure personal items such as pens, coins and badges before working on or inside the aircraft. Inspect every tool before use, because a damaged, dirty or out-of-calibration tool can affect the quality of the work even when everything else is done correctly. And take part in regular FOD walks of the work area.
Where these skills are learned: EASA Part-66 training
These practices are not improvised. They are part of the knowledge base required for the EASA Part-66 aircraft maintenance license. Module 7 (Maintenance Practices) covers workshop practices, the use and care of tools, and safety precautions. Module 9 (Human Factors) explains why maintenance errors happen and how to prevent them, from complacency and time pressure to poor communication between shifts.
At 360 Aviation Life, we prepare maintenance technicians for their EASA Part-66 license through 100% online training designed for people who work while they study. Students have access to our own learning platform, Aerobot, our AI academic assistant available 24/7, and in-person review sessions before each examination session.
Conclusion
Tool care is part of the maintenance process itself. Every aircraft released to service depends on the technician’s knowledge and judgment, but also on the condition of the tools used and the control over them. A clean, complete toolbox is part of every safe release to service.
Want to train as an aircraft maintenance technician with an EASA Part-66 license? Explore our training programs or talk to an advisor: [link a Training / Contact en inglés]
Sources:
- Setting up a FOD program for the maintenance facility — AviationPros: https://www.aviationpros.com/home/article/10389063/setting-up-a-fod-program-for-the-maintenance-facility
- Oxygen safety — Airbus Safety First: https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/oxygen-safety.pdf