The so-called Stradivarius is a great aircraft, but it also requires a lot of care and preventive maintenance. The owner of this magnificent CASA 131 trusted us to carry out the annual check-up. Assembly of a revised carburettor, complete overhaul of the landing gear, complete adjustment of the wing tension, manufacture of new engine cowling bosses, the work ended with a morning of test flights and adjustments then a return trip to Switzerland.