Avionics Technicians

March 1, 2007
Do they really exist?

Having spent the majority of my aviation career fixing problems on aircraft associated with systems incorporating wires and having been told on numerous occasions that I have an analytical mind and a creative thought process, I have had a recent revelation. In the eyes of the Federal Aviation Administration, I do not exist. Yeah, they know me because I have an Airframe and Powerplant (A&P) license but having a last name like Sparks seems to have prevented me from spending much time in the wheel and brake shop.

65.1 Applicability

FAR Part 65 prescribes the requirements for issuing the following certificates and associated ratings and the general operating rules for the holders of those certificates and ratings: air-traffic control-tower operators, aircraft dispatchers, mechanics, repairmen, and parachute riggers.

I see no mention of avionics or electronics technician. In contrast, the European Aviation Safety Agency (EASA) has included in its Part 66 several categories describing the privilege of return to service. These include B1 and B2:

Category B1 aircraft maintenance license shall permit the holder to issue certificates of release to service following maintenance, including aircraft structure, powerplant, and mechanical and electrical systems. Replacement of avionic line replaceable units, requiring simple tests to prove their serviceability, shall also be included.

Category B2 aircraft maintenance license shall permit the holder to issue certificates of release to service following maintenance on avionic and electrical systems.

In addition to creating the ratings, EASA has also created an educational structure to ensure those rated have an understanding of what is required.

The FAA Airworthiness Inspectors Handbook Volume 2, section 235 defines the areas considered to be avionics.

Many aircraft currently under development use electronics to control everything from air conditioning to thrust reversers. In fact fly by wire is about to make its debut in a business jet within about a year. In accordance with Federal Air Regulation (FAR) Part 65:

65.81 General privileges and limitations

(a) A certificated mechanic may perform or supervise the maintenance, preventive maintenance, or alteration of an aircraft or appliance, or a part thereof, for which he is rated (but excluding major repairs to, and major alterations of, propellers, and any repair to, or alteration of, instruments), and may perform additional duties in accordance with §§65.85, 65.87, and 65.95. However, he may not supervise the maintenance, preventive maintenance, or alteration of, or approve and return to service, any aircraft or appliance, or part thereof, for which he is rated unless he has satisfactorily performed the work concerned at an earlier date. If he has not so performed that work at an earlier date, he may show his ability to do it by performing it to the satisfaction of the Administrator or under the direct supervision of a certificated and appropriately rated mechanic, or a certificated repairman, who has had previous experience in the specific operation concerned.

(b) A certificated mechanic may not exercise the privileges of his certificate and rating unless he understands the current instructions of the manufacturer, and the maintenance manuals, for the specific operation concerned.

Paragraph "b" content can have significant implication regarding how we dispatch future aircraft. Recently during a telephone conversation with an old friend who is planning to receive a "new generation" business jet in his fleet, the question of training came up. It seems the aircraft manufacturer has planned the maintenance course to include the basic airframe as the core of the program and will offer a five-day optional "avionics course" as a follow on. My friend wanted to know my thoughts on attending the course. I pointed out FAR 65.81 paragraph b. Avionics has taken on a whole new meaning in recent years and integration between airframe and engine systems with what used to be considered "cockpit stuff". In today's world replacing a circuit card used by an integrated system may in fact influence the operation of aircraft pressurization, wheel braking, or engine performance. In accordance with the regulations, a clear understanding of system integration and data paths is critical to safe return to service.

Several years ago while visiting a factory-owned service center for an airframe manufacturer, I overheard a conversation between a maintenance crew chief and an avionics technician. The crew chief was discussing the benefit of the A&P license to which the avionics person responded "I don't need that to do my job". The response was correct given the fact they both worked for a repair station. But what happens to the avionics technician when he is offered his "dream job" working for a first class private flight department. Could this person safely repair a problem? Probably, but when it comes to signing off, someone else would have to do it.

How does one become an avionics technician?

In my generation there were two distinct methods. The first was to specialize in aviation electronics while in military service and then after discharge, join a manufacturer or repair station maintaining systems that were often somewhat less sophisticated than those they were trained on. Many in this group went on to receive their A&P certificates along with a Federal Communications Commission (FCC) license. In my case, I had some electronics knowledge prior to entering aviation and after a while my bosses would start assigning the electrical discrepancies to me. Having been fortunate enough to work for several organizations that were pro-education, I had the opportunity to attend courses that targeted avionics systems.

Several grass-root efforts have been initiated to establish a minimum knowledge requirement for today's aircraft technician with regard to electronics. The National Center for Aircraft Technician Training (NCATT) is one such group (www.ncatt.org). By partnering with established aviation entities it has set forth to create a standard for classifying an "Aircraft Electronics Technician" (AET). And, NCATT has created a curriculum specifically designed to provide the knowledge along with an exam which measures the technician's level of achievement.

So what exactly does an avionics technician need to know?

Like most everything else in aviation there is really no "one size fits all" definition. Several broad areas including the bench technician, systems installer, and flight line maintenance all require special and specific skills but do share certain commonality. The basics of our business are essential parts of the formula. After all, troubleshooting an auto pilot without any idea about theory of flight and fundamentals of flight controls would most likely not produce the desired result.

Another big part of the knowledge base is risk management from first a safety perspective including self-preservation followed by financial consequence resulting from mistakes. Many people say troubleshooting is a knack and cannot be taught. It is probably true that those who have a natural analytical thought process might enjoy the challenge of resolving a complex system problem where those who are not so blessed may struggle a bit. Having the knowledge of how the device should work and the ability to identify the components that could generate a negative influence will enable most to resolve the majority of discrepancies. In other words, developing or refining problem-solving skills along with having a strong knowledge of the overall system at hand will enable most people to achieve success.

Familiarization with the tools of the trade is another essential. After all there are areas where using an analog meter over a digital one may provide the key to a rapid solution. There are of course areas where the flip side will apply and using an analog meter may actually damage the circuit under scrutiny. The oscilloscope is now the tool of choice for many technicians who routinely work with digital and discrete circuits. Devices used to insert or remove pinned wires from electrical connectors are assumed by many to be explanation free yet many people do not realize that certain tools only apply to specific connector manufacturers. Even the use of basic hand tools needs to be understood. Using a magnetized screwdriver while working on magnetic compass system components may result in less than desirable results.

Proper understanding of standard practices including corrosion protection and electrostatic discharge (ESD) can have a major impact on component longevity and proper system operation.

Understanding certain principles and function of specific components are another requirement. The big three are resistance, inductance, and capacitance; acting independently or in various combinations can result in numerous circuit anomalies.

Semi-conductors such as transistors often occupy the time of troubleshooters and knowledge of microprocessors is essential. A high percentage of the avionics systems being produced today contain some type of integral diagnostic device. Many will display the results of the self-interrogation in a sequenced code. Having knowledge of binary, octal, and hexadecimal numbering will help make sense of the displayed data.

Proper understanding of technical documentation is another important aspect of the avionics technician. Once again the documents used may depend on the specific job being performed. One document that should never be overlooked is the aircraft maintenance schedule often referred to as Chapter 5. Typically this is the document that is approved by the local airworthiness agency. This reference often provides either functional or operational tests that can be accomplished on the aircraft to determine conformity of the device or system under scrutiny. Chapter 5 may also provide a guide to required testing of other systems that may have been integrated with the troublesome circuit. For example, replacement of an air data computer not only requires a pitot static system leak check and verification of proper instrument function it also may require a transponder test if the air data computer supplies altitude information to the transponder directly.

The parts catalog is another document often requiring more than just familiarization. Often when ordering a replacement component, alternates have been implemented. In some cases the substitute components require nothing more than remove, replace, and test; while in other instances software will have to be loaded or other devices replaced or modified to properly interact.

Just like the aircraft maintenance technician one of the major challenges of the avionics community is trying to stay current with technological advancements and airworthiness requirements. Continued education is a must.

Having recently returned from Savannah, GA, where I had an opportunity to witness the positive results of a training partnership between Gulfstream Aerospace and FlightSafety International, I realized that the evolution from airplane mechanic to aviation technician complete with avionics knowledge is a reality. I hope this philosophy takes over elsewhere and the current thinking that avionics knowledge is optional is overturned.

I wonder, if the FAA does not recognize avionics technicians then perhaps the IRS won't recognize us either? I also wonder if they will let me continue to write from my jail cell.

Jim Sparks has been in aviation for 30 years and is a licensed A&P. His career began in general aviation as a mechanic, electrician, and avionics technician. Currently, he is the manager of aviation maintenance for a private company with a fleet including light single engine aircraft, helicopters and several types of business jets.