Wow, there is no way to really discuss this subject in a quick email but I can summarize by saying that "solidly mounted" covers a lot of ground. You might think a picture would tell the whole story but it doesn't. By one definition, my cores are solidly mounted because there is a solid metal connection between engine mount (solidly bolted to engine) and the bracket holding the cores. The connection is a piece of 3/16 thick 4130 flat stock that is rigidly bolted to the mount with the core cantilevered out on the other end. This forms a spring of unknown rate. The spring is more or less optimally oriented so that the primary vibration vector is bending this spring. The U shaped brackets holding the cores are lined with a 1/8" thick rubber sheet to eliminate chaffing & point contact loads on the rather fragile core. The top & bottom U brackets are clamped lightly together by 4 threaded rods. Lightly is another fuzzy term but an important one. It determines the amount of compliance in this part of the system. This system has flown for > 1350 hours over a period of 10 years and not failed. I suspect it would last no more than a few hours if it were on a Lycoming. Bottom line: The cores are not really solidly mounted and details matter (a lot). Tracy Crook --- Original Message ---
From: "Russell Duffy" <13brv3@bellsouth.net>
To: "Rotary motors in aircraft"
<flyrotary@lancaironline.net>
Subject: [FlyRotary] Re: aluminum hose bungs/fittings,
evap core mounting
>OK, there are a number of you out there that have
cores mounted to the engine. Do you have them solidly
mounted, or are they on an effective cushion of some
type? Can you post some pics? Has vibration been an
issue with any of your mounting methods?
>Thanks,
>Rusty (shaken, not stirred)
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