The More Complex the Better

By George Marsh | November 1, 2003
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The Lufthansa Technik AG (LHT) avionics facility at the Hamburg airport can service everything from a galley water heater to an inertial navigation unit or a flight management system. But it is best suited to take on the more complex tasks.

So asserts Kai Uwe Meifarth, manager, avionics components, with LHT’s Aircraft Component Services Division. As Meifarth explains, "Whereas most airline maintenance, repair and overhaul [MRO] shops can tackle a coffee maker or other cabin equipment, fewer can deal successfully with a software-intensive flight management computer [FMC] or a traffic alert collision avoidance system [TCAS].

"At LHT, however, because we handle nearly all of the electronics, radio and instrument work for the fleet of over 300 aircraft operated by our parent organization, Lufthansa [German Airlines] and its subsidiaries– Lufthansa CityLine, Lufthansa Cargo and Thomas Cook–we can offer the same wide capability to outside customers. Currently about half of our workload is for third parties."

Staff and Facilities

Some 300 staff members work in the LHT avionics facility’s three major shops, which cover 90,000 square feet (8,360 square meters) and handle about 55,000 component shop events per year. This makes LHT’s Hamburg base one of the world’s leading centers for maintaining avionics and associated onboard electronics.

Although it is not an independent profit center, the Hamburg avionics facility operates autonomously, boasting, for example, its own dedicated engineering, material planning and purchasing functions. Electronics, radio and instrument (ERI) workshops occupy nine floors in two multistory buildings near the center of LHT’s 247-acre (100-hectare) base at Hamburg. They include two Class 20 clean workshops, a licensed shop for engine control units, a stores area, and major installations of automatic test equipment (ATE). Activities are organized into five streams: electromechanical, electronic, calibration, engineering and logistical operations.

In the navigation zone (area of shops), Avionics Magazine witnessed a range of line replaceable units (LRUs) undergoing troubleshooting and repair. In some cases, full Level 3 repairs are carried out, but when it makes more sense economically, diagnosed boards are sent to the original equipment manufacturer (OEM) for repair. Work on digital systems is carried out on one of the facility’s 21 ATE systems, which include five ATEC 5000s and four of the latest Series 6 ATEC test systems from EADS. Each Series 6 ATEC costs more than $1 million. The latest of these test systems arrived at LHT in January, and a fifth is contemplated.

Alongside these top-end automated systems, LHT has benches dedicated to traditional "watchmaker" technology. They appear dated but are still useful. LHT supports, for example, electromechanical instruments for Boeing 747-200s, B737 Classics, and Airbus 320 and 340 standby systems.

Axel Mueller, manager, avionics engineering, was our guide for the shop tour. He joined the company 42 years ago as an apprentice and has witnessed huge technology transitions, from pneumatic instruments to early "glass" panels to the present increasingly integrated, software-intensive digital cockpits. Like Meifarth, Mueller is a Dip-Ing. (engineer qualified to diploma level), as are many of the managers and technical staff members at LHT.

Mueller says the latest generation of ATE has permitted huge productivity increases. Avionics can be left hooked to an ATE all night if necessary, with no operator intervention, to check thousands of lines of software code for required functionality. Nights and weekends are used for particularly long test runs; one full-authority digital electronic control (FADEC) test, for instance, lasts for up to 16 hours because it has to be conducted at three temperatures. Despite the high level of test automation, a good operator with at least several years of experience can speed the process significantly, according to Mueller.

Tackling NFF

LHT technicians apply all the resources they can muster to combat the "no fault found" (NFF) issue. They look for underlying causes by environmentally screening a suspect unit to see whether a fault becomes manifest under certain conditions of temperature, pressure or vibration. They found that an engine control unit, for example, displayed a fault only within a particular 20-degree temperature band. Connections are checked for fit and corrosion, too. If the cause is not established, the box is sent back to the OEM for special investigation. If still no fault is found, LHT will circumvent the problem by requesting an exchange unit.

Mueller states that the proportion of NFF incidents is not the 25 percent often quoted. Rather, he contends, equipment is deemed faulty because flight or cabin crews do not use microphones correctly or because antennas have become corroded, for example, on instrument landing system (ILS) equipment. Close collaboration with the Lufthansa German Airlines line maintenance personnel, who often have firsthand knowledge of the systems they maintain, also helps LHT technicians combat the NFF issue, not to mention keeping themselves rooted in operational reality.

Working on a wide variety of systems, LHT technicians also have witnessed a shift in avionics maintenance and NFF. Many nuisance faults, for instance, are now software-related and eventually are cured with software patches.

On a floor dedicated to radio support, LHT has a range of test equipment, including a Faraday cage to provide an isolated electromagnetic environment. Systems assessed and repaired range from emergency locator beacons (ELTs) to enhanced ground proximity warning systems (EGPWS) and TCAS 2. LHT claims to handle all communications equipment except (so far) satellite communications. The facility has met major upgrade and retrofit requirements for the Lufthansa fleet, including 8.33-kHz spacing on VHF voice communications and Change 7 software on TCAS. It was to start implementing Mode S data links in September.

Twenty-Five Hundred Coffee Makers

A separate LHT department in Frankfurt handles in-flight entertainment (IFE) equipment. Lufthansa German Airlines has been an early adopter of new IFE equipment; it recently became the launch customer for Connexion by Boeing’s broadband service, which provides e-mail and Internet access to the aircraft cabin.

Another workshop area in Hamburg is equipped with versatile test benches, developed in house, for assessing a wide range of linear and rotary electromechanical actuators from various manufacturers. Nearby is an area for testing generators. Yet another area is dedicated to maintaining cabin equipment, ranging from espresso coffee machines to ovens, ceiling lights and water heaters. Engineers developed a test bench for testing the almost 2,500 coffee makers that pass through the shops each year. These units suffer sensor fatigue, heater element failure, "furring" (pipes accumulating calcium deposits) or other defects.

Workplaces throughout the LHT shops are well equipped, allowing multiskilled technicians to handle every aspect of a job–from initial inspection to troubleshooting and repair and final release. In-house technicians also design and calibrate test equipment, maintain the ATEs, and develop innovative repair schemes.

Technician Training

Some technicians are recruited from outside sources such as the military or other airlines, but many have learned their trade in Lufthansa’s own Technical Training School. The final 12 months of an initial three-and-a-half-year apprenticeship is spent "hands on" in the shops. There, technicians progress from Level 0 (starting level) through Level 1, at which point they can clear certain components, primarily motors, actuators and sensors, for return to service. They then advance to Level 2, at which stage they can sign off on complex equipment such as communications radios, engine instrumentation systems, flight management computers or automatic flight control systems. This level of competence is generally reached after about six years of training and experience, plus several written and practical examinations.

Education at LHT is ongoing, however. Avionics training coordinator Hans-Juergen Nibbe sees to it that technicians and engineers take sufficient follow-up courses to stay abreast of new technologies, as well as joint airworthiness requirements (JARs) and other regulations.

A further important asset at LHT is the piece part store, housing some 25,000 part numbers. A logistics office handles the material planning and purchasing and also organizes modification scheduling, transport, training and qualification, and information technology (IT) services. A separate engineering staff of about 30 persons provides project management, documentation and tooling services, plus JAR 21 design services and JAR 145 (aircraft maintenance) oversight.

Holding Steady

While the recent aviation downturn and the enhanced reliability of modern commercial avionic equipment have combined to squeeze the avionics MRO business globally, LHT has managed to keep its avionics-related revenue remarkably steady. This reflects successful efforts to attract a wider customer base, including operators that have decided to outsource their maintenance. The company also has shifted its emphasis by supporting later-model aircraft, which generally have been used more because many older models are parked in deserts awaiting better economic times. LHT has accomplished an increase in annual throughput from 45,000 components six years ago to 55,000 today without a significant expansion in workforce or space utilized.

Other factors contributing to LHT’s relative success include economies of scale, close control of costs, and partnerships at the component services level with avionics OEMs and with Star Alliance partners–in particular with Scandinavian Airlines System (SAS) over Boeing 737NG work and with United Airlines over B777s.

LHT avoids peaks in expense by expanding only gradually the new aircraft types it supports. "For instance, our capabilities on Airbus 330 and Bombardier CRJs are modest at present because these are more recent additions to our parent organization’s fleets," says Meifarth. "But we will build them up progressively towards 100 percent.

"It takes time to gain experience with current technologies, and we consider each case [for new investment] on its merits. This year we have been preparing for Lufthansa’s introduction into service this autumn of the A340-600."

CRJ avionics, not generally ATA-Spec-2200-compatible, are currently returned directly to the OEM, Rockwell Collins. The company is more likely to gear up for the avionics of the latest CRJ model, the ATA-Spec-2200-compatible CRJ700.

Avionics engineering departments such as LHT’s are planning ahead for the advent of the giant A380, for which the learning curve obviously will be protracted. Happily, LHT has proven successful in retaining expertise. Members of its staff appear willing to stay with the company for the long term–25 years or more in some cases.

Beyond Single-Unit Support

Meifarth believes that, in the present climate, beleaguered airlines require, more than ever, that support costs be both competitive and predictable. They therefore prefer to use reliable one-stop shops that are capable of assuming total MRO responsibility. This is borne out by a reduced volume of single component maintenance (SCM) business in favor of more comprehensive fixed-rate total component maintenance (TCM) and total component service-(TCS) type contracts, Meifarth reports. Subscribers to the latter contracts benefit from fixed-rate maintenance along with access to a large pool of exchange components, avoiding the need to invest in their own spare parts or to await the completion of maintenance on specific units.

LHT looks after the avionics for nearly 500 aircraft, operated by 70 customers, under TCS contracts. Also available, at a higher level still, are comprehensive total technical support (TTS) and total operational support (TOS) solutions. TTS covers all types of maintenance, from line to heavy checks and including engines, avionics and other systems. TOS augments TTS coverage with flight planning, consultancy and other operational support services.

Meifarth says the company holds approvals by the airworthiness authorities of 38 countries and by most avionics OEMs. And it is a JAR 21 design facility that has developed solutions which the OEMs subsequently have adopted. For example, a replacement bearing developed in conjunction with a gyro manufacturer subsequently became standard.

JAR 145 maintenance approval enables engineers at Hamburg to examine the advisability of including particular service bulletins. They also can analyze component reliability, taking into account their own experience plus that of the parent airline. And LHT adds value by developing repairs for components and parts that previously had been declared non-repairable.

LHT technicians are in close touch with line maintenance crews and other operational staff at Lufthansa’s Frankfurt, Munich and Berlin hubs, as well as its outstations. With component service centers located around the world, from Dallas and Los Angeles in the United States to Beijing and Shenzen in China, the organization can claim geographical presence within the time zones of most customers.

LHT strives to meet customer expectations on turn times. Across the board, LHT’s average turn time is 12 days. Flight management and automatic flight system computers are turned around in less than six days, while 30 percent of those components leave the shops within a day.

Despite OEM focus on the aftermarket to compensate for depressed sales of new avionics, Lufthansa Technik appears to be maintaining its market share, thanks to a wide customer base, the increasing number of airlines outsourcing their maintenance to reduce costs and its established branding as a reliable "blue chip" supplier. An added advantage is its eagerness to take on the most complex support tasks.

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