Comprehensive maintenance ensure comfort in flight


OVER recent years, Indonesian aviation has recorded a number of aircraft accidents, ranging from minor incidents to major accidents that claimed a lot of lives. In reality, air travel is the safest mode of transportation because airlines must follow tight procedures. Why, then, are there a lot of air accidents here? The reasons are many and varied, ranging from technical aspects to human error.
Aircraft maintenance plays an important role in the aviation industry as it is related with public safety. If an airline repeatedly has incidents, big or small, caused by technical reasons, it will lose its credibility.
Aircraft maintenance, however, is costly and generally accounts for 10 to 20 percent of the total operating costs of an airplane. Obviously, a new aircraft requires relatively less maintenance than one that is much older. A new aircraft would be years away from a major overhaul.
In general, there are two categories of aircraft maintenance costs. First, direct maintenance cost, which is the cost of materials, equipment and workers directly related to maintenance as a whole. Maintenance costs are calculated by the provider of aircraft maintenance facilities, such as GMF-AeroAsia.
Second, indirect maintenance cost, which is the cost related more to the organization of an airline than to the design of the aircraft. One of the elements playing an important role is the aircraft maintenance checks, which are periodical checks that are done on all aircraft after a certain amount of time or usage. There are four types of checks done on airliners, namely A Check, B Check, C Check and D Check.
A Check is done about once a month. This check is varied, depending on the type of aircraft and flight hours since the last check. In this type of aircraft maintenance, the engine is checked, the systems and components as well as the structure of the aircraft. For a Boeing 737 Classic, this check is done after 300 flight hours, whereas in the case of a Boeing 747-200 and a Airbus A340, after 650 and 450 flight hours respectively.
B Check is usually conducted every three to five months. This entails cleaning, lubricating, replacement of worn tires, replacement of batteries and inspection of the internal structure.
An aircraft is subject to a C Check every 15 to 18 months. This type of aircraft maintenance is a comprehensive inspection that covers hidden parts so that any damage or cracks in the internal parts of the aircraft can be detected. For Boeing 737-300 and 737-500, the C Check is conducted after 4,000 flight hours, while for Boeing 737-400 and Boeing 747-400 it is conducted after 4,500 and 6,400 flight hours respectively. In the case of Airbus A-330-341 this check is done every 21 months.
The most detailed inspection is the D Check. This inspection is generally an overhaul. For Boeing 737-300, 737-400 and 737-500, this inspection is conducted after 24,000 flight hours. Boeing 747-400 requires a D Check after 28,000 flight hours while for Airbus A-330-341, after six years.
However, the national aircraft maintenance center can meet only 40 percent of the total demand for aircraft maintenance. In fact, the demand for aircraft maintenance in Indonesia is worth US$750 million to $800 million annually.
The Indonesian Aircraft Maintenance Shop Association/IAMSA) predicts that demand for aircraft maintenance will continue to rise. At present, the demand grows 5 percent worldwide while in the Asia Pacific, it grows by 10 percent. IAMSA membership stands at 57 aircraft maintenance shops, 67 percent of which are controlled by PT GMF AeroAsia. The remaining 33 percent are controlled by PT Nusantara Turbin and Propulsi, PT Merpati Maintenance Facility, PT Aircraft Services and PT Indopelita Air Services.
IAMSA is also planning to build three aviation maintenance centers in Surabaya, Makassar and Batam. It is also committed to applying a safety management system as of January 2009.
The latest news in the domestic aviation business is that PT Garuda Maintenance Facility (GMF) AeroAsia has been entrusted to take care of the maintenance and repair of jets owned by Southern Air, a cargo airline from the U.S. High quality and a relatively low cost are the reasons why Southern Air has appointed GMF. This trust is an achievement for GMF as Southern Air, which is one of the largest cargo airlines in the world, is quite selective in choosing aircraft workshops overseas.
With an MOU for a contract worth dozens of millions of U.S. dollars, GMF will take care of the maintenance of jets owned by Southern Air, namely Boeing 747s and Boeing 777 Cargo, which will operate here as of next year. All Southern Air aircraft will undergo major inspections, namely C Checks and D Checks at GMF. Meanwhile, other clients of GMF, which is owned by flag carrier Garuda Indonesia, include a number of large airlines such as KLM, Air France, Phuket Air and Martin Air. (Iwan Suci Jatmiko) 
The Jakarta Post, November 04, 2008