Engine accessories: starters, pumps, sensors, valves

If you imagine an aero en­gine—with its com­pres­sors, tur­bi­nes and com­bustor—as a human heart, then its acces­sories could be likened to the coro­nary blood vessels. Just as the human heart is sur­rounded by a net­work of arteries, the engine is sur­rounded by a range of sup­port­ing com­po­nents. The analogy continues: acces­sories are split into numer­ous com­po­nent groups that are critical to the func­tion­ing of the whole, as in the human heart. Should these acces­sories fail, the engine is at risk of suf­fer­ing some­thing akin to a heart attack: the engine can no longer op­er­ate safely and the air­craft must either per­form an emer­gency landing or else remain grounded. Mean­while, the costs in­curred in­crease with every passing minute.

Christian Ludwig and his team are there to do all they can to avoid such a scenario. “And if it does hap­pen, we’re the ones who can get the air­craft back in the air the fastest,” says the Di­rec­tor of Acces­sories Op­era­tions at MTU Main­tenance Canada in Richmond. Here, right on the door­step of Vancouver and its inter­national air­port, MTU has es­tab­lished its Acces­sory Repair Centre of Excel­lence (A.R.C.). Initially, the plan was simply to ag­glom­erate acces­sories activ­ities within MTU but, as the com­pany con­tinued to invest in the per­son­nel and infra­structure required for acces­sories repair, it quickly saw the oppor­tunity to turn it into its own, effective business.

Extreme complexity

“The biggest challenge when it comes to acces­sories is the enor­mous complexity in­volved,” says Ludwig—a level of com­plexity that only a select few in the market have a handle on. One single en­gine has an aver­age of 80 dif­fer­ent acces­sories, manu­fac­tured by 15 to 20 dif­ferent suppliers. The array of com­po­nents ranges all the way from starter motors, fuel pumps, hydraulic pumps, ac­tua­tors, sensors, and valves all the way to wiring har­nesses and tubing. “When you’re catering to all sorts of dif­ferent engine types, like we are, it quickly amounts to a bewil­dering array of hun­dreds of dif­ferent acces­sories that you have to manage,” says Ludwig. Just the logistics of gath­ering to­gether the individual parts re­quired to re­pair a wide range of acces­sories is an enormous task in itself.

On top of that, you have to factor in the range of geo­graphic and time con­straints that come into play when you have repairs to be carried out, and you need to have ex­perts on hand to do the job. “For in­stance, if an air­line is flying to Hawaii and ex­peri­ences a leaking fuel pump, they will need an opera­tional replace­ment as soon as pos­sible,” says Ludwig. “At the same time, we need to re­serve enough ca­pac­ity to deal with main­tenance and re­pairs on engine acces­sories that come in as part of a sched­uled engine shop visit.” Then there are acces­sories that need to be checked after a set number of hours in ser­vice. “We have to be able to cover all that work at the same time, or else our cus­tomers will lose interest,” says Ludwig.

450 repair procedures

Accordingly, the accessory repair process has to run like clock­work. “When an acces­sory comes in, an in­coming test shows us what isn’t working. Then we take the unit apart and give it a good clean be­fore we perform visual in­spec­tion and tests on the com­po­nents,” explains Ryan James, who is re­spon­sible for engi­neering at the A.R.C. Repairs are then carried out, followed by reas­sembly and final testing, before the acces­sory is sent back to the customer. Repairs draw on some 450 dif­ferent pro­cedures. And if the re­pair work is taking too long, James’s col­leagues will simply take a com­plete, func­tion­ing unit of the same model from storage, and send that back instead.

As a result, defective acces­sories can be replaced with func­tion­ing ones within be­tween four and 24 hours. “With some air­lines, we have agree­ments to keep replace­ment units for their fleets in central storage. From there, the units are put onto the next air­craft to land at the air­port where the ex­change is due to take place,” says James. “That’s when we achieve the four hour replace­ment rate.” But even the 24-hour turn­around time is often faster than what the com­pe­tition can offer, com­pe­tition that in­cludes com­panies such as Luft­hansa Technik, Allen Air­craft, AJ Walter and Triumph, as well as the manu­facturers of the acces­sories them­selves. The latter in par­ticu­lar often specialize in just a few acces­sories, and are slower in the decision-making process because of the size of their company. This means that they are rarely able to match the service offered by MTU’s A.R.C.

All-inclusive service package for accessories

The Canadians are also extremely flexible, offering acces­sory repairs for every­thing from busi­ness jet engines such as the CF34-3 to the mighty GE90 that powers the Boeing 777. “Our all-inclusive service pack­age for acces­sories is par­ticu­larly ­popular,” says Ludwig. This is a compre­hensive service whereby MTU takes care of all an air­line’s acces­sories. This includes the man­age­ment of line replace­able units (LRUs), specific ­acces­sory com­po­nents that can be re­placed on location during routine opera­tions. “This demanding service offering is possible only ­because around half of our em­ployees in this segment work on site with the customer,” says Ludwig.

Everything points to growth. Last year, the A.R.C. repaired 11,000 acces­sories, bringing in busi­ness amounting to 60 million Canadian dollars. The 98 members of the A.R.C. team cur­rently serve 114 customers, which in­clude air­lines, engine manu­facturers and even the U.S. Air Force. “We’ve set our sights on almost doubling our rev­enues by 2020,” says Ludwig. In other words, busi­ness is booming.