Warning -MT Autogyro Rotor Blades

[Adrian S]

[JAL]

Adrian I remember you telling me two years ago that you thought that The MTO blades will be life limited, I cant remember exactly the hours you thought but it was around the 800 hour mark.

[flapper]

You can"t be serious Adrian; after all this is German engineering you are writing about : is there a "tongue-in-cheek" smilie?Joe

[flapper]

My MT 03 Pilot Hand Book instructs me to torque my rotor blade bolts (16, in fact there are 18) to 10Nm; the download version from the factory instructs me to torque to 15Nm; Service Bulletin AGAUS 02/2010 instructs me to torque to 20 Nm. Which, if any, is correct. Also I believe that these figures may have been transposed as ft/lbs in the UK; would over/under tightening of these bolts be party to the present problemsJoe

[blakemorem]

Yeah Joe this is an old topic and has had a lot of debate. The over tightening or under tightening of hub bolts yes absolutely will cause problems. Imperial and

[gyroo]

Hi guys,Seeing that this thread has been re-activated, ASRA"s position is products from Autogyro.de that users and operators must adhere to the latest manufacturer"s directives. This is particularly important now with MT"s because there are now 3 known blade extrusion profiles and 2 blade strap arrangements, as well as the permanent manufacturer"s directive on blade inspection for cracking and the constrained life on series 1 blades and extended life on series 2 blades.The only other point I noticed in the preceding post was mention of silicon lube to get "true" torques.All members must carefully note that all manufacturer"s torque specifications and the AC 43 AN fastener torque chart all assume that the fastener is DRY and completely free from oil or grease and otherwise unlubricated. Be AWARE that the use of Locktite-type thread locking compounds is also not taken into account in the AC 43 AN fastener chart. If one looks at any of the wide variety of reliable and reputable technical publications on Google relating to fasteners, the major concern with lubricated bolts is that they are likely to impart severe crushing loads on the components they are holding together well before they get up to the proper torque mark on a digital or analogue torque wrench, and to me this sounds awfully like what will happen with blade or propeller hubs if you"re not careful.Mark ReganTech Mgr