Strix StratoSurfer Motor Mount Design Study

Introduction

This page is written to support my findings with regards to modifying the motor mount structure and durability on the Strix Stratosurfer. In no way should this write-up be construed as a negative comment or complaint about this excellent model.

=== Design ===

The stock mount has very little foam in cross section to support the plastic mount pieces and the motor so any additional weight or leverage will put this foam piece under enormous stress. Below is a general sketch and some photos of an un-assembled stock foam mount and you can see where the weakness is.

Below is a picture of a failed mount showing how small the area of foam support is. The area highlighted in yellow is all that supports the motor and the motors center of mass is above the weakest part of this support putting it in an extreme stress condition anytime the plane comes to a fast stop.

If there was some kind of structural tie-in to the wing mount bolts it would be considerably stronger. Below is an illustration of just one idea for a stronger part to be embedded into the foam.