Betreff: Balancing of B737 Flight Controls, Press Release Nov 2014 FIT-M

Keywords: B737, Balancing, Flight Controls,Repainting, Paint thickness, Non-destructive measurement, NDT, Airbus, BoeingDear Editor,Attached please find our press release of November 2014. It describes the method and a product how to reduce the effort when balancing the flight controls after repainting of an aircraft. Please feel free to contact me if you have questions. An information on how you used this press release would be welcome.Best regards, Johann Hinken

Optimizing the Balancing of B737 Flight Controls The reduction of aircraft weight has always been a major challenge for the aircraft industry. An alternative for aluminum was to replace it by carbon composites (CFRP). The Boeing 787 and the Airbus 350 are outstanding examples.However, CFRP has been used in aircrafts since the 1960s. The flight controls of the B737 are specific examples. A significant amount of these aircrafts remains in use so far and has to be repainted occasionally. The Structural Repair Manuals of the Boeing 737 prescribe balancing the flight controls after repainting. This procedure may be performed off the aircraft or on the aircraft. The off-the-aircraft procedure requires demounting, measuring on a special jig, and reassembling. This is rather laborious.The on-the-aircraft procedure is much less laborious. However, it requires measuring the paint thickness distribution before stripping the old painting and after applying the new paint. Through the paint thickness differences a computer program calculates the necessary adjust of the balancing weights. There's been a problem so far: the paint thickness on CFRP could not be measured in a non-destructive way. In this case, the airlines often have applied the wedge cut method (paint borer), that leaves small holes in the surface that must be finished later.Nowadays, this effort can be performed in a faster and easier way - FI Test- und Messtechnik GmbH (FIT-M), in Magdeburg/Germany, has developed the FSC, a non-destructive paint thickness gauge that can be used for paint on CFRP and CFRP with metal mesh, providing the paint thickness value within 3 seconds. Users report that using the FSC, rather than the paint borer, reduces the balancing effort of flight controls by 70%.The FSC works with low power microwaves. It is qualified by Airbus and approved by Boeing. "We are glad to collaborate with the aircraft industry by introducing this microwave-based NDT instrument into the market." said Johann Hinken (Managing Director of FIT-M). FIT-M has been working on non-destructive testing (NDT) with microwaves technology for several years.For further information visit www.fitm.de.(See the attached photo. Figure caption: "The FSC1/7 consists of a hand-held module (r.) and a control and display module (l.)")