Bolt on engine frame

The AN5 bolts holding the engine frame and the parachute brackets were all placed tail forward to facilitate inspection. In line with the desirability of avoiding nylon locknuts firewall forward, all-metal locknuts (MS21045-5) were used

Upper engine mount bolt positions: AN5-11A bolts, with AN960-516 washers under the head (aft) and nut (forward)

Lower engine mount bolt positions: AN5-7A bolts, with AN960-516 washer under the head (aft) and AN960-516L washer under the nut (forward)

Inner parachute bracket bolt positions: AN5-10A bolts, with AN960-516 washer under the head (aft) and AN960-516 washer under the nut (forward)

All bolts torqued to 130 in-lbs and marked

Note that there are additional shim layers:

• 0.4mm shim + 0.63mm shim associated with the upper engine mount bolt positions
• 0.4mm shim + 0.63mm shim associated with the lower engine mount bolt positions
• 0.4mm shim associated with the inner parachute bracket bolt positions

Referring to

Torque wrench re-calibration - We Build Planes

I chose a nominal torque setting of 141.2 in-lb (15.9Nm) which I previously measured to yield 122 in-lb (13.8Nm) of actual torque. The KAI gives a range 11.3Nm - 15.8Nm, so the setting is right in the middle of the range. Even if my calibration efforts are totally bunk, and the wrench is in fact accurate, the torque setting is just at the top of the recommended range.