Murphy Moose Upgrades Summary Most of the upgrades I’ve built into this aircraft are key, structural improvements. I trust these two—out of many—examples amply illustrate why this aircraft is head-and-shoulders above a stock Murphy Moose. Flight Control Hinges The standard hinge assemblies that Murphy ships for the elevator-to-horizontal stabilizer and the vertical fin-to-rudder are simply metal-on-metal. There is no bronze bushing, no iolite bushing—simply no provision for reducing surface wear. The below image shows the obvious hole elongation on Murphy’s standard hinge assemblies:

The below image shows upgraded hinge assemblies that I have made by a machine shop that specializes in aircraft part fabrication. These parts feature sealed KP-4 bearings and are made out of 6061 T6 aircraft grade aluminum billet.

The question is, which hinge assembly do you want in your aircraft? Tailwheel Stinger Attach Structure The standard way Murphy designed the stinger attachment is using a single bolt to attach the stinger (which is made out of 4380 steel alloy) to FUS-360 (which is made out of 0.250 6061 T6 Aluminum)—reference below diagram. What happens, within a short period of time, is that the holes in FUS-360 begin to elongate—they simply wear out. FUS-360 is attached to the underlying structure using AN-3 bolts and AN365 nuts. When it becomes necessary, one would think that one could later simply order & install new FUS-360 parts from the factory. However, there is no access panel behind the structure to access those nuts (or bolts, depending on which direction you assembled such). Alternatively, one could move the stinger attachment to another FUS-360 hole—after all there are 5 options initially available. The potential problem here is moving the stinger changes the castor on the tailwheel assembly; Hence moving holes could

potentially initiate tailwheel shimmy due to adverse castor. Here is a diagram showing the standard stinger attachment:

Some builders resorted to designing entirely new structures for this entire area. Short of that, the below upgrade adds two additional attach bolts as well as additional 4130 steel supporting structure and 4130 bushings. Now one effectively has an I-Beam structure. Furthermore, the FUS-360 pieces are attached using nut plates to ease any (unlikely in my case) future need to replace the FUS-360 pieces. Again, please review the below images. Do you want the standard factory stinger attachment, or my upgraded version?