We starting running the second life of the fatigue testing cycles on Friday and to our delight it ran beautifully well, so ran through Friday night as well. Set designer Steve gave up time on his Saturday morning off to come and shut down the rig safely for the rest of the weekend. Always absolute dedication from us here in ASTC could cause us to miss Saturday Kitchen Live.
We came back in on Monday and started our usual rounds of inspection to find that the engine attachment bracket (the bracket that takes the main load up into the wing spars) was starting to show signs of cracking.
The solution was to take it off, do some hasty cutting up of bits of box section we had and got the whole thing welded up much stronger with the help of our friends at Nuclear AMRC. This time we’ve really gone to town and beefed the bracket it up to help ensure it won’t happen again.
It was ready to reinstall this morning and we are ready to continue with the fatigue testing again today. We have already clocked up about 20,000 fatigue testing cycles out of the 71,633 required for the entirety of the second life testing, so we are getting through it quite quickly now.
Luckily for ourselves and Game Composites, nothing untoward has happened so far during testing with the extra damage we have caused the airframe. Game Composites came in late last week and did some repairs to the rear stabiliser of the aerobatic aircraft because we had noticed a little crease was developing.
It’s quite remarkable the aircraft can be repaired. A Stanley knife is used to cut out the damaged patch of composite material on the fuselage to reveal the foam layer in the middle. The foam is removed and smeared with glue, but not just any old glue is used; the glue has what only can be described as lots of hollow tiny glass balls in it, making it lightweight yet very strong. This replaces the foam and a patch is stuck over the top with resin which we leave to cure overnight.
As the aircraft being hand laid-up (or built by hand), it’s relatively easy and cheap to repair, as any repairs can also be done by manually without having to send it back to a manufacturer. As it would at the hanger or in the field.
With the repairs to the engine bracket made, we will be back up and running with testing today and we will hopefully conclude the second life fatigue testing next week so we can get ready for further testing. Exciting things to come for us!