Engine Operations Training


By: Mark H Goodrich – 2015

Over the past few years, the aviation industry has increasingly taken notice of the need to broaden and enhance flight crew training in airplanes. That call has been the subject of editorial and white paper presentations since the introduction of the so-called “automated” airplanes in the mid-1980s, but as such things go, languished until a spate of serious incidents and accidents began to fulfill the prophecies seen so clearly by some. While industry writ large and regulators were taking the position that enhanced technology decreased the need for training, experience was showing that it required more training, not less. In addition to knowing how to manually perform tasks ordinarily handled by automatics, it was also necessary for operators to know how the computers worked, where sensor data was collected and how to maintain oversight to ensure proper functioning of the automated systems.

What has and continues to escape serious attention – indeed even notice in many quarters – is the associated requirement for both flight crew and maintenance personnel to receive training on the operation of modern engines. Even before airplane, autopilot and flight management systems made the quantum leap to computer control and monitoring, engine design and control technologies were already moving ahead of the “airframe curve”. High-bypass engines introduced with the first wide-body airplanes in the early 1970s were game-changers. Power was substantially increased. Engine temperatures for hours at cruise were above prior values for the peaks at takeoff thrust. Reverser design and operation was entirely different. The potentials for damage from foreign object, ice and ash ingestion, delayed acceleration schedules and temperature exceedences exponentially increased, and yet personnel continued to operate new models using formerly established procedures.

Engines are expensive, and losses of productive time when airplanes are down, plus the expenses for repair or replacement, add further to those costs. Indemnity often does not cover damage to an engine from a failure. Yet somehow these factors have been insufficient to promote a change in thinking about how to improve the training of both flight and maintenance crew. When called in to assist with an investigation, I’ve often found that no one wants to clearly attribute an engine failure to any specific act or failure to act by the operator, including even to a non-approved procedure that may be used regularly, despite that failures raise the specter of airframe damage and personal injury, up to and including death. In some cases, engine failures are quickly chalked up to foreign object damage in an effort to prevent an investigation into the true facts. While bureaucratically convenient, this artifice places even the costs of collateral damage outside the parameters of indemnity, and impedes efforts to improve both safety and efficiency. In most cases, back-room arguments ensue between the operating airline and its engine manufacturer or repair facility over the cause in an effort to try and spread the economic pain, and any investigation into the causal chain of events falls somewhere between cursory and non-existent.

As engines become more sophisticated, engine manufacturers report problems from both flight and maintenance operations that arise from simple failures to conform to operating instructions of the manufacturer. Often, neither pilot’s operating data nor maintenance and inspection manuals for an airline are updated to stay abreast of new operating procedures. In most cases, this can be traced to the bringing forward of text from prior manuals, and in substantially all cases, this process escapes notice during review by regulators, who are increasingly less experienced and knowledgeable about advanced technologies.

The path of least resistance for training is to fall back on what is required by the applicable regulations. Even for pilots, that means training for engine operations is mostly limited to start malfunctions. The presumption is that engine operations for taxi, takeoff, climb, cruise and landing will be subject to computerized control and monitoring. The most detailed airline manuals include only a page or two of generalized policies on engine operation, usually reflecting precisely the same words in the manuals for several fleets of different airplane and engine types. When challenged, operations management often responds that such training is handled by check airmen during initial operating experience. But, the absence of guidance to check airmen for such training leads to the conclusion that it is ad hoc and non-standardized under the best of circumstances.

In the case of maintenance personnel, the problem is more acute. Often, even supervisory personnel have not received specialized training for engine start malfunctions or airplane ground operations, pro forma processes to obtain approval for starts, ground runs and taxi notwithstanding. While certification standards for a repair station may require a program for such training, the ways in which tick marks appear in boxes and approvals are granted is highly variable and often amounts to more of a wink and a nod, rather than training in-fact.

As an engineering test pilot with experience in aircraft, engine and supplemental type certification, as well as an operations manager for certified repair stations, and a manager for airline operations on both the flight and airworthiness sides, I have been personal witness to these issues for five decades. Let’s consider some specific events.

I was retained by an airline to power up the engines and airplane systems for a Boeing 777 on a twenty-day basis in conformance with its “flyable storage” program. During one regular visit, I was directed to the manager for the certified repair station. He handed me a sheaf of papers, each one a certification that I had performed “engine start and taxi training for Boeing 777 model airplanes”. He intended that ten of his people would thus become certified, apparently by watching me perform two engine starts on one model of engine from among the several approved for the airplane. Declining to so assist, I suggested two options. The first was to develop a training curriculum for his facility, including engine start, run and taxi training. The second was to enroll his people in the manufacturer’s training curriculum for that same purpose. In both cases, the training at issue would consist of two days in the classroom and three days in the simulator, where each individual would not merely observe, but function as the starting and assisting crewmember for practice with the panoply of engine start malfunctions on each of the possible engine models to be seen in service. Further, operating procedures and airplane limitations for taxi would be covered, with taxiing practice in the simulator, and finally in the airplane. “Do you know much that costs,” he inquired? I assured him that I did, and advised that, “The cost for ten of your people, plus travel, lodging and per diem for the week, will total about one-fourth of your self-insured retention for the first engine you destroy in the absence of proper training.” He rejected my recommendation out-of-hand as prohibitively expensive.

I was hired by a lessor to reposition a Boeing 747-400 out of heavy check, and upon our arrival saw that the repair station was about to complete the engine runs. I asked to observe. I recognized the inspector from years previously, when he was employed by the central maintenance base for a legacy carrier. As we boarded, I immediately saw that the center fuel tack was filled to capacity, while the wing tanks varied between almost empty and one-half full. I pulled the inspector aside to advise him that there was a limitation prohibiting tugging or taxi unless the tanks had been filled “on schedule”, with full main tanks prior to filling the center tank to capacity. “It’s no big deal,” he said. “We do it this way all the time.” As structural damage can result, I insisted we consult the Airplane Maintenance Manual, and persuaded him to defuel and refuel the airplane “on schedule”.

While waiting, I asked for a copy of the Task 71-00-00 procedures he intended to use for the engine starts and runs. Although the airplane was equipped with CF6-82Cs, he was about to use the procedures for P&W-4056 powerplants. Indeed, in the breast pocket of his shirt was his well-worn data card booklet from airline days, reflecting the start procedures for the Pratt engines installed on the airplanes operated by his former employer. Regardless of their model or manufacturer, all engines started and run by him were subject to the procedures he had been using for some twenty years.

A new lessor for a Boeing 737-300 wanted a power assurance check as a part of the lease initiation and acceptance inspection, and the repair station performing the heavy check and bridging tasks was so commissioned. The idea behind a power assurance check is to track the relationship between N1, N2, EGT and Fuel Flow at a carefully measured temperature and local barometric pressure, thereby predicting those values across the range of power production. It is usually accompanied by an associated takeoff power check, or acceleration and deceleration check. My team was on-site to inspect records, validate AD and SB compliance, and oversee the heavy check. As the inspectors were preparing for the engine tests, I noticed that the “trim charts” – those that specify adjustments for the N1, N2 and EGT based on temperature at the engine intake and uncorrected barometric pressure – were not in the documentation for use during the engine runs. In contravention to the published test requirements, temperature and barometric pressure were being taken from airplane sensors and flight deck displays. My insistence that the tests be performed in strict conformance to the published procedure of the manufacturer was met with an obvious disdain for that attention to detail, which was seen as completely unnecessary.

Many repair stations treat engine start and run operations for two-engine airplanes as a “one-man” procedure. The co-pilot seat is often occupied not by a trained assistant, but rather by someone who just wanted to come along. Engine start, run and taxi procedures all require a team-crew concept. Watching carefully for a start malfunction, and then working as a team to quickly complete remedial procedures, requires training as a crew and coordinated action. Even the most experienced airline flight crews find themselves in conflict with other airplanes during taxi operations, and no single flight deck seat allows adequate vision around the airplane. Professional engineering test crews – bringing both aeronautical and engineering skills to the process – train and operate as a team. The managing team member is primarily responsible for operating the machine. The assisting team member or members keep track of protocol, procedures and checklists. They monitor instrumentation, call out developing issues, and record results. In some cases, flight deck printers may be used to download and memorialize data. On some older types, printers may not be available or data screens capable of holding only a single “data trap”, in which case photographs of the screen presentations are taken as the tests proceed. The point is that a test crew – whether flight or airworthiness in nature – cannot be selected like a pick-up team for a neighborhood ball game. To safely operate the machine while accurately achieving and documenting results requires training, and a coordinated team-crew effort.

Even for ground operations – which may seem relatively free of risk – knowledge of airplane systems and conformance to established protocols and procedures is far more serious than merely knowing how to start and steer in the absence of malfunctions. Nothing brings this issue into sharper relief than the events of November 15, 2007, at Toulouse with the Etihad A340-600. While details of this run-up crash have become the stuff of tribal lore, the BEA did assess fault to the non-standard conduct of engine run-up tests, the failure to follow established and published procedures, and the ad hoc nature of the flight deck crew, which was not operating as a trained team. The loss of control destroyed the new airplane.

The rationale for trying to evade the incurrence of training expense is usually an inability to see a connection between expenditure and return. Management too often sees training as a pure expense, when the reality is that it is an investment in safety, efficiency, regulatory compliance, lower insurance premiums and other factors. That those things are difficult to visualize in the abstract does not mean they are illusory.

In airline and maintenance endeavors, this mindset can drive decisions to define the need for training not by what is logically necessary, but rather by what is required under the minimum standards of applicable regulations. Unfortunately, regulators often connect the need for training to revenue operations. In the test and ferry business – like engine runs performed during maintenance, an almost completely unregulated process – this often results in stretching the issue to the point of absurdity. In the case of flight crew, airlines will assign people without relevant training and experience to perform ground test, flight test and ferry operations. Crews with no international experience are sent around the world, sometimes causing crashes because of simple failures to know the air law or traffic control procedures that are effective in other countries. Those without engineering degrees or credential are assigned to perform post-maintenance, repair and modification test flights with potential issues that are beyond their experience or understanding. In the case of lessors, pilots are contracted from employment agencies on the basis of having some prior experience in a type, and paired to form a crew absent currency, training as a crew or the use of common flight standards, procedures and checklists. In such ad hoc operations, there is no understanding as to the duties of each crewmember for normal operations, much less for irregular or emergency situations. These are accidents looking for a place to happen.

Some twenty years ago we were contracted to perform a post-maintenance engineering test flight on a Douglas DC-8 following major work on flight control and stall warning systems during a heavy check. Unfortunately, the airplane was not ready as predicted, and after a week waiting for the maintenance work to be completed, our crew was sent home to await a call upon completion. When the call did come, we were told to stand down, as the airline had decided it was too expensive to bring back the engineering test crew, and would instead use line pilots it already employed. Two weeks later, the DC-8 crashed during the ensuing flight, killing the airline crew and three maintenance technicians riding as passengers. The NTSB highlighted the absence of any training or credential to perform test flights, and decisions to perform high-risk test events under instrument meteorological conditions.

In November 2008, an Airbus A320 was being returned by its airline lessee to the lessor, and undergoing a “return acceptance flight check”, characterized in the lease documents as a “test flight”. Despite the absence of engineering credential, training or experience by the flight crew, it was agreed the tests would be in conformance with the document used by Airbus Test Pilots in post-production test flights. During a series of low-speed maneuvers at low altitude, control was lost. The BEA determined that a failure of the angle of attack sensors provided bad input to the automatic flight control systems, and resulted in the automatic driving of the trimmable horizontal stabilizer (THS) to the full nose-up position. The position of the THS was displayed on flight deck instrumentation and it could have been manually moved to a normal flight position, along with downgrading normal and alternate flight control laws to effect direct law. But airline crew training does not include in-depth systems knowledge or non-standard problem solving. Had the airplane been operated by an engineering test crew, such maneuvers would not have been undertaken at low altitude, and there is a high probability that the flight control problems would have been identified, and remedial action taken. The crew and five other occupants were killed and the airplane destroyed.

One of our test crews was dispatched to a repair station in France for the purpose of doing the post-maintenance test flights on an Airbus A-320, and then ferrying the airplane to its new operator in Southern Africa. While waiting, the lessor called to advise that the lease agreement and new registration were already effective. The airline was to send a highly-experienced flight crew to perform the post-maintenance engine runs, and lease acceptance test flight. We were to recall one test pilot, while the other would observe the tests from the flight deck jump seat. Under our company policy, I informed the lessor that we would only ride as an observer if satisfied with the technical and aeronautical credential of the airline test crew. Upon their arrival, we learned that the captain had just completed upgrade training and was sitting reserve. He had not yet flown a single flight as an A-320 captain. The co-pilot was a new hire, and had just completed initial training. Neither had flown outside their home country. When I advised a manager with the lessor that our engineering test pilot would not ride as an observer under those circumstances, I was told that we were unreasonable and would never work for his company again.

Like the airplanes they power, engines are becoming ever-more sophisticated. The days of common design, limitations and operating specifics are long behind us. With reciprocating radials and even early turbojets, the procedures for starting, run-up and operation were remarkably common, just as were flight deck technologies. But now strict conformance to the highly variable documentation of the manufacturers is critical to ensure not only that we service, maintain and operate the products correctly, but also that we avoid initiating future product failures that may occur hours and months later, jeopardizing the safety of the flights that rely upon the integrity of our work.

Regardless of whether regulators require it, establishing training programs to ensure proper standards of professionalism are met is our responsibility, and safety management systems are the perfect vehicle through which to address that responsibility. The duty of regulators is to see that minimum standards are met. But, as it always has been, professionalism is the non-delegable challenge and duty of industry.

Copyright 2015 MRO Network Publications

“Engine Operations Training” was first published by the MRO Network of London, U.K. in its “Engine Handbook: 2016”.