07 de September de 2010
ATTENTION WITH THE SCREWS OF THE REDUCTOR!
We strongly call your attention for the safety of the pilot and of others to read this statement carefully and follow the instructions that we indicate below. We want to emphasize on the screws of the gearbox to replace. As you should know in August we released a statement on our Web page that some screws have been defective and the head of these screws break with few hours of use. We have 2 cases where the 5 screws from the gearbox crankcase broke, result : lost part of the gearbox during flight together with the propeller, assuming a grave danger for the pilot and the others (although it is necessary to remember that we can not fly over people or urban areas).
The cause of the breakdown of these screws is that the deoxygenation process has not been done properly after the galvanizing process, and as consequence that the originally made screws of black steel 8/8 lose their characteristics and reach to break like glass. We used to use 8/8 screws galvanized to have no oxidation and ensure a better appearance over time on the engine knowing that mechanically it is best to use 8/8 black steel screw. We have also mounted stainless steel screws and it seems that these give no problems.
Since beginning of August the gearbox leaving our factory are mounted with metric 6 stainless steel screws to ensure 100/100 liability and have no more such problem.
However, we want to communicate that they are only a small consignment of screws which are defective as there are many gearbox which have not had this problem.
To prevent, all engines mounted with M5 galvanized screws must stop flying until the change of these screws by stainless steel or Black steel 8/8 screws (without galvanization)*. Please contact your dealer to provide you with those screws or contact us directly if you find it easier. Those screws can be found at any hardware store. We remind you that the torque setting for M5 x 20 mm screws is 6 to 6.5 Nm and we recommend to use a normal hardness fixing glue.
Thank you for your attention and once again we apologize for any inconvenience.
One way to check if your bolts are in stainless steel or not is to take a magnet, it will not stick if it is stainless.
* The factory is not responsible of any consequences occurring if flying without having changed these screws.