Luke was flying on the Buddy Box and was doing such a good job that about 8 minutes went by without my having to intervene at all. I was enjoying his success and cheering him on! So when he finally got into an orientation he couldn't get out of, it caught me by surprise. No problem, we were still high. "I got it..." Wait, I'm not getting any response to my inputs! She's diving straight down! Heart pumping, cold sweat, not breathing... WHAT THE HELL IS GOING ON! SHE"S DYING! I suddenly realized I hadn't let go of the trainer switch, Luke was still the pilot, and he was shaking his sweaty hands dry watching the emerging disaster! I let go of the trainer switch, gaining control just in time to break the dive, but not in enough time to remain airborne. She struck the ground hard with a glancing blow and a nerve wrackingly loud thump... I knew I had flattened out the trajectory, but I wasn't sure it was enough. It was a long hundred yard walk through the blackberry field to the hills of Mordor. I still wasn't breathing, saying a soft prayer to the Flying Spaghetti Monster hoping it wasn't too bad, so I didn't think to get a photo of the crash site... (You'd think I have been blogging long enough to remember by now...).
The wing had popped off cleanly, knocking out one of the front pegs and shearing out the aft wing mount. The wing itself was unharmed. The motor was bent upwards and the firewall crushed in at the top. The metal X-mount was bent, but curiously the prop was intact. The motor hand turned cleanly, but later I would see that not just the prop adapter was bent, the motor shaft was too just outside the outrunner. (I removed it, tried to straighten it, but then the motor outrunner now rubbed against the stators. It was toast). I repaired the wing mount with CA and epoxy, rebuilt the firewall with chips and popsicle sticks (very useful things, those popsicle sticks), and some salvaged plywood. Its not pretty but functional. I ordered a Poweup 450 Sport motor from HeadsUpRC(my favorite parts supplier) to replace the Eflite 450 motor. A more powerful 450 motor at half the cost. I decided that with a more powerful motor, I would take a 40A ESC from Frankenheli and put it in the Alpha, so I have removed the Eflite 25A ESC.
I also took the opportunity to change the front white LED of the Turnigy nav lighting system (more on that later) to a forward pointing alignment, and built a curved housing over it.
All in all it looks pretty good, albeit not scale perfect! The motor should be here soon. Luke and I will be back in the air, and I will stay awake at the switch!
The post crash pic...
Pieces of popsicle stick strengthen the front of the firewall. The entire top section (with the two blind nuts) was crushed back into the fuselage.
A view from below. The opening for the forward nav light.
View from behind the firewall. I would later put a cross piece along the bottom of the front cover, where a piece is clearly missing.
The aft wing mount was sheared cleanly off the plane. I replaced it with CA and buttressed it with epoxy. The top of the forward aft fuse behind the mount was also broken off. I removed the cote and rebuilt the balsa, and squeezed some balsa chips into any remaining gaps. CA the whole bugger, as Greg Reed recommended, I drowned it all in CA. Thank goodness for the 20g Locktite CA.
Built a sheet balsa enclosure for the forward nav light, which I wanted to be forward facing. I didn't think of doing this mod until I had coted the cover. I removed the cote and recoted it.
To get a smooth finish, I used dry wall spackle. I sanded it as smooth as I could, but couldn't get it just right. The hard part was getting cote to lay down over it smoothly over the curved surfaces. I think I can do a better job next time.
Dried and sanded Not so good with the smoothing.
Try as I might I could not get the cote lay down wrinkle free. I tried a variety of application methods, and think I can get it right next time. I can make this look a lot better.
I was using a Velcro strap across the bottom of the plane to keep the battery hatch in place. The magnets work well, but they can let go in a hard G maneuver, and I don't want to lose the cover. I don't like the Velcro strap on the outside, so I put in a cross bar (popsicle sticks...) and laid some Velcro across it and the hatch. Works nicely.
She looks very good post repairs!
Waiting for the motor. Can't wait to take Luke back up on the box. I don't think it will be long before he is doing takeoffs and landings as well!
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