Tool Control

Various Tools and PartsTool control is an effective way of accounting for all tools that are used on aircraft.

Many years ago, I worked alongside contractors on Phantom F4J UK aircraft that the UK had purchased as a stopgap measure after the Falkland Island crisis. The contractors were making some modifications to the aircraft that required the engines to be removed; I helped them with this work. Each person on the team had their own tools and carried them in a variety of containers. The quality of the tools varied, as well as the containers, and they were loosely held sometimes several layers deep in each tray and perhaps as many as a hundred tools in a five-drawer tool box.

With no standardization and no requirement to check tools at the end of the working day, it was each individual’s responsibility to account for his tools. With hundreds of tools to check and workers helping themselves to others’ tools, it was impossible to account for them. In those days, this situation was not an isolated incident and many companies worked with a similar regime. Not surprisingly, when the aircraft were delivered to the Royal Air Force, tools were sometimes found along with other maintenance equipment.

In the late 1980s, I remember talking to some military maintainers who worked on the Vulcan bomber; they had just gone into a wing fuel tank and found a workbench that was probably used to help fasten the fuel-tank bag in place. Incidents like this eventually led to a change in working practices that saw the introduction of tool control in the aerospace industry.

The military have for many years used tool control to great effect. They procure premium grade tools; etch them to uniquely identify them to a station, squadron, flight and toolbox; and color- code them for quick identification on the units. Furthermore, no personal tools are allowed in the work place. In the tool containers, each tool has its own resting place that is shadowed/highlighted to indicate its absence; in recent years sheet foam has been used to layer each drawer or tray and is cut to house each tool.

When a tool is taken, the worker using it places a numbered plastic tag against the tool space or shadow. The tag identifies who is using it. Moreover, each tool kit is booked out to the aircraft that it is being used on, using tags controlled by the engineering operations rectification controller; this person checks that all the tools have been accounted for before he signs the aircraft over to operations for flight-line servicing.

When a work task is completed, the person completing the task checks that all his tools have been returned and that all his tags are accounted for; maintenance personnel sign for completing these checks as part of the work order paperwork. All tools are controlled through tool stores, which keep specialized tools, small and specialist equipment, cleaning rags and other general-purpose equipment. Each item — tool, box and hardware — is identified in the same way as the tools in the toolboxes and accounted for in the same way.

A person is given the duty of controlling the tools — a job often held by the squadron or flight supplier/logistician — and serves the tools over a counter. The supplier checks the completeness of the tools and tool kits, and performs a second check after the tradesperson; in addition, they perform tool inventories at least at the start and finish of each day.

If any tools are missing, a check is done immediately using the tag system to identify the aircraft it was being used on and the person using it. If that person cannot find the tool nor has any recollection of where it was last used, a larger scale search is carried out. At this time, the trade supervisor or trade manager should be informed and a thorough search initiated.

In the unlikely event that a tool is still not found, an all trades search should be completed using zoned areas of the aircraft. The removal of access panels and equipment should also be considered. Control runs and controls should be checked and independently confirmed to be free of restrictions. Inspection devices — lamps, borescope and even x-ray — should be considered.

If all this does not find the tool, then the senior engineer or maintenance officer would have to consult with the chief engineer on the station and consider a check flight or flight test. The test is a single flight that is recorded in the aircraft Limitations Log and involves a period of inverted flight to attempt to free the tool from its hiding place.

On landing, further inspections are carried out in the same way as originally completed. If still not recovered, an entry is made in the ADF (Aircraft Deferred Faults) Log that will call for further inspections of the suspect area on the next scheduled maintenance. If it is not found then, the ADF entry is cleared. This situation seldom occurs, as there are many checks and balances in place to maintain safety.

An effective Tool Control Program is vital to flight safety, and is evaluated regularly by quality assessment teams from the squadron, unit, wing, and command. These teams ensure correct procedures are in place to control hazards and prevent problems. In past years, these checks were to confirm standards and look for any discrepancies. Today, they are more to ensure that systems, orders, and training are in place and effective. It is more a top-down than bottom-up approach and has won the support of the management and workforce.


Having worked for both the RAF and USAF in command and staff appointments, I have witnessed the benefits of comprehensive reporting. Through studies carried out at DERA (Defense Evaluation and Research Agency) on reporting and improvements to the RAF Report Form 7014, information is obtained on every FOD occurrence. The information includes the sortie details preceding the event, weather, location, and debris detail — if known or presumed — and statements from the associated squadron maintenance officer, station FOD officer, and chief engineer.

The reports are fed back to command and to the RAF FOD Prevention Officer for consideration of any follow-up action or visibility. Every six months, the Reports are collated, and a written report is published for dissemination to every station and FOD officer. The reports can provide trends indicating problems, either on a unit or with an aircraft type, which help target a response and prevent recurrence.

Moreover, the design authority — engine manufacturer — can also use the reports when considering modification or future designs. Debris indentations are identified throughout the engine and, through repeated events, designers can determine where blades are most susceptible to damage. Thorough reporting is essential to any FOD prevention program. The system operated by the RAF is perhaps the most comprehensive in the world.

Deployed Prevention

While on military deployment and operating in a new environment, extra vigilance must be taken to ensure a FOD free operating location. In many cases it is a short notice deployment with no forward inspection, and the parking ramp is a transit setting with many different aircraft from different commands. There may be no central FOD control person looking at the whole picture. That leaves everyone on their own, so here are some tips on reducing the danger to your aircraft:

  1. Bring your own FOD prevention tools with you. FOD Containers, Magnetic Sweepers, etc.
  2. Take a good look at aircraft positioning — not just yours. Are their aircraft positioned in such a way that their exhaust could be tossing objects towards your aircraft? Also consider engine maintenance run-up areas and how they might affect your aircraft.
  3. Be positive and diplomatic when dealing with the home base. The wrong perception of your organization could create new problems.
  4. What is being used for snow removal at home base or on deployment? Many locations may still be using metal street sweeper type brushes, which leave a trail of metal bristles behind. Consider switching to nylon brushes or initiate a sweeping program to insure their removal.
  5. Develop a deployed FOD Prevention Handbook for the person tasked with managing the program at the deployment location. Basic information on this subject is available on this website. Since the regular Wing FOD Program Manager at your home base may not be there, insure the person assigned as the deployed FOD Program Manager understands the importance of FOD Prevention and is suitably motivated.

Operating Bases

Runway sweeping is usually carried out by mechanical sweepers to clean the surfaces by collecting debris using a vacuum, brushes, and sometimes, magnetic media. Most operating stations have a sweeping plan that virtually segments the airfield into blocks that are attended to at least weekly.

In addition, runway sweeps can be requested on demand and are worth considering after repairs, extensive aircraft work or following inclement weather — like strong winds and rain —that can move debris onto the airfield. Although some airfields use road sweepers, new specialized FOD sweepers are available that can clean surface areas and down between the gaps in the concrete blocks, keeping flight operations areas scrupulously clean.

Many military airfields have open days during which vast crowds are allowed onto the airfields. The airfields are transformed into fairgrounds with external catering and amusements brought in to keep the visitors fed and entertained. Flying displays are usually scheduled for the busiest times. Special attention is required to keep the operating areas free from debris, especially on days where strong winds can blow litter onto the field. Hooded litter bins should be freely available and placed close to the generating sources, like the food and drink stands.

In addition, at the forward edge of the crowd line, netting, like that used by builders or around airfield repairs, can be employed to prevent litter migrating. During the day, work teams should be used to collect and empty litter into lidded trash bins or contained bulk waste disposal areas.

At the end of the day, or before operational flying commences, the airfield should be walked for FOD. Everyone should be employed in this task to ensure that all the litter and other human-generated debris is removed. Furthermore, on the aircraft used for static displays, the aircraft should undergo checks for loose articles by all trades and disciplines.


As a young airman working on the line, I used to think that no one outside my squadron was interested in what happened in my area of work until something went wrong. I then very quickly realized the visibility that mistakes had and how quickly action was taken to try to prevent recurrence. Reporting was the medium for highlighting occurrences, FOD, incidents, or accidents. Thankfully, there were very few accidents but I vividly remember them, the missing aircraft and the men who never returned from their missions.

It was then a strange time to be a technician. I was initially concerned for the safety of the crew and then left to wonder, searching my memory, if I had worked on the aircraft or had any of my friends, and if we were in any way responsible. The crew rooms were full of chatter and questions were always being asked. The aircraft paperwork would be immediately impounded and a team — board of inquiry — convened to determine the details leading up to the accident and figure out what had happened. Recommendations were made and command headquarters appointed blame.

Thankfully, accidents seldom occurred, but their aftermath left a deep scar that took time to heal. I always hoped that the last one would be the final one but knew that there were too many variables or factors that, when driven together to form a chain, could result in another. However, through them, I realized just how many organizations were involved  in flight safety and how many people saw what occurred out on the squadrons and wanted to help.

Most of the reports generated on the Unit found their way to command headquarters for further comment, action, or remedial attention. I was on 29 Squadron at RAF Coningsby, Lincolnshire, UK, and, in those days, had to conduct an intake and fan inspection on every after-flight servicing. One day I entered the starboard intake and, with a keen eye, found a one-inch crack on the second stage of the fan; this was an unusual event and those who know turbine engines will know how difficult it is to see past the first stage.

I was really excited and ran to the line supervisor to report my finding. He immediately called a propulsion technician to verify my finding. This was duly done, and the aircraft was placed unserviceable and made safe for maintenance. In the hangar, the engine was replaced and many people were involved over two shifts, engaging technicians from multiple trades. Moreover, the engine was sent to the bay for strip and overhaul. All this work took many man-days and cost a great deal of money to rectify.

Through studies I carried out later in my career, I determined that FOD cost the RAF about 20 million GBP (British currency), almost 30 million US$ per year!

Management Responsibility

In the military, management is sometimes overlooked in the face of strong leadership. Leaders take a dominant role, but managers ensure that procedures are set and practiced, modified, and improved. However, in many areas, like maintenance and logistics, the leader and the manager are the same and often take the form of a commissioned officer or senior non-commissioned officer.

With these people, the responsibility for safety is always a priority, but this is balanced against operational needs and cost; it is pointless having the safest aircraft and best working practices if the aircraft cannot fly. Conversely, you cannot have the best mission launch rates at the expense of safety and aircraft loss.

With FOD control, the manager has to assess risk, implement and enforce standards, and check to see that working practices continue to be effective. These practices are often delegated; however, while the role may shift, the responsibility remains.

Consequently, managers must be reactive in dealing with damage and proactive in dealing with prevention. They must commit and support at every level and be prepared to assist as well as enforce. In my education as a young engineering officer, my mentors used to say “GOYA — Get Off Your Ar** —” and see firsthand what the problems are. Talk to the people that are at the front line where the “rubber meets the road.” These people are the ones that use the orders that you want to put into effect, and they will provide the feedback. They know the how, why, what, and when, the effectiveness and the best way forward.

However, be assured that they will not write to you with their concerns. Equally, irrespective of how well an order is written, they will not put into action something that is stupid or causes them unnecessary hardship. The best orders are those which they help form and those that take their needs into account. The best managers have the ability to understand the needs of everyone and support the key initiatives and practices that have best effect.

Moreover, these managers are quick to praise and recognize outstanding effort with award and reward. In FOD Prevention, award may be a certificate and reward maybe public recognition of having “gone that extra mile.” From my largely military perspective, I have seen that the military are at the forefront in leading and implementing FOD Preventative measures, but whether the area of concern is commercial or military, I know that it takes a committed team to have the best effect.

Everyone’s Responsibility

“FOD is everyone’s responsibility” is often repeated, but I often wonder how many take the saying seriously. There remains a pressing need to actively minimize debris and report activities that could lead to damage or follow-up events to help prevent recurrences. Furthermore, each of us can help to eradicate the problem. Everything helps, no matter how small. Pick it up, talk about it, draw or place a poster to illustrate it, share ideas, participate and work together.

It is everything about being part of a team. Irrespective of where we work, we all have a part to play. If we are in any way connected with flying or the support of operations, we can help. Even as fare-paying passengers, we have a duty of care and consideration. Do not throw litter and do not throw debris where it can migrate into the path of an aircraft.

Think outside the boundaries of your job and be prepared for the unexpected. Be willing to help. One man against FOD is good, but a team effort is better. Work with the team and build a team through which we will all benefit.

Return to FOD Military Prevention – Part 2.

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