The roll bar support arm, a part of the canopy rail on the completed Mk 1 fuselage is easily bent. There is a tendency for pilot and/or passenger to put their weight on this piece when exiting the airplane. On the latest fuselage for the iS/U the factory has addressed this issue by adding a supporting gusset.
Shown in Figure 6.
This can be retro-fitted to our older fuselage, although it is not offered by the factory as a retro-fit kit. The F-1254A part is available for about $5. The plan shows the top row of rivets to be AN470AD3 solids but that is not possible after the ship is built, so I just used all LP4-3.
This is a worthwhile upgrade for the older fuselages with little cost or time involved.
Shown in Figure 6.
![i-RRSQVsG-L.jpg](/community/proxy.php?image=https%3A%2F%2Fphotos.smugmug.com%2Fphotos%2Fi-RRSQVsG%2F1%2F36f04b34%2FL%2Fi-RRSQVsG-L.jpg&hash=8a319f42210af404e3c9a88b1f9cee75)
This can be retro-fitted to our older fuselage, although it is not offered by the factory as a retro-fit kit. The F-1254A part is available for about $5. The plan shows the top row of rivets to be AN470AD3 solids but that is not possible after the ship is built, so I just used all LP4-3.
![i-xG3V3zq-L.jpg](/community/proxy.php?image=https%3A%2F%2Fphotos.smugmug.com%2Fphotos%2Fi-xG3V3zq%2F0%2Fd1864d0a%2FL%2Fi-xG3V3zq-L.jpg&hash=dd4a09c07e183ba8d0a015958ee11077)
This is a worthwhile upgrade for the older fuselages with little cost or time involved.