Borescopics – Insight in even the most remote areas

This extract is taken from the article published at http://www.lufthansa-technik.com


The complete article:

Engines are one of the most complex components of an aircraft. Some types might be big enough for a human to stand upright in the air intake, but their inside is filled up with complex technical devices hard to see and even harder to reach from the outside. To inspect or repair for example a compressor blade within the engine it sometimes takes a complete disassembly, resulting in high costs and a loss of time.

To avoid the expensive dismantling of the engine, most visual inspections at Lufthansa Technik are carried out with a so called borescope. This special inspection tool was adapted from its primary use in medical applications and consists of a thin tube containing an array of optical lenses. It can be inserted deep into the cavity of an engine part to be inspected. The optical array is surrounded by a fiber-optic that transports light from a connected source directly to the area of inspection. From there the light is reflected back, and through the optical array it pictures the image of the examined area directly in the operator’s eye or a camera attached to the borescope. This function allows the qualified personnel of Lufthansa Technik to gain an incomparable insight in hidden structures normally invisible without disassembly of the engine.

For examination with a borescope, aircraft engines are equipped with numerous sealable notches which provide access to all different sections, from the combustion chamber to every single compressor stage. For the latter, only one aperture per stage is needed, because all blades can easily be rotated into position before examining them with the borescopics equipment. For fixed components, which are not accessible in a direct line, Lufthansa Technik uses a special type of borescope, the so called flexoscope. Instead of lenses it uses a glass fibre optic within a bendable hose. With several meters in length it allows the operators to access even those parts that can not be turned into position.

More information about aircraft maintenance borescopes here