ZF: the black hole of gearbox overhaul
My MGB was lost there for three months, and TRGB for two months
My MGB had to go to EID for overhaul, who then had to send it to ZF, whereupon it disappeared. The TRGB was an even worse drama
Re the 117 MGB, my understanding is that Kawasaki have the design approval, but (all) the MGB's are assembled by ZF, regardless whether they go into a KHI or a Eurocopter BK. Check any 117 MGB, look for European inscriptions from the production line checks (crossed 7's, funny shaped 1's, etc) by the Inspectors.
KHI having design approval is a nightmare, nothing gets done in a hurry coming out of Japan. European 117's have many advantages over the Japanese built units: eg any KHI service must incorporate ALL previous lower hour services at the same time, ie a 1200 hour must include a 600, 300, 150 and a 50 hour inspection, even if they're done out of sequence
European servicing allows far more latitude, for the same airframe
