It’s been forever since I updated this, so a quick pictorial review of things that have happened:
I modified our cheapo Turnigy 9x transmitter so that we could flash it with open-source ER9X firmware. This transmitter uses a fairly generic microcontroller for its “brain,” but the firmware it comes with is clunky at best. The RC geek community has come up with far better options, some of them pretty specialized. ER9X does way more than I’ll ever need, and is very intuitive once you get used to it. Hobby King is now selling a fancier version of the transmitter with the open-source firmware installed, and not giving credit to the community that developed it. Imagine, a corporation taking open-source code and pretending they own it! Unheard of!
An AVR programmer (connects the microcontroller to your USB port) plugs into this funky plug. I guess the cool kids just build the programmer into the transmitter and have a USB plug on the outside for computer connection. Ironically, I couldn’t get my AVR programmer to work with Linux, so I had to use the evil Windows to flash the transmitter. Now, I can actually program parameters for different aircraft (including any sort of multi-copter, etc.) from my computer. Not that I’ve actually done that. Seriously, this is powerful stuff, especially for the DIY drone crowd.
Please don’t think that I have more than a vague idea about how this stuff works. I prowled numerous forums and watched many videos to figure out how to do this. I was just following the recipe.
So we flew a couple of more times (still just me actually flying), then this happened:
After the successful rescue, we fixed the plane, and finally made it out to fly. Since the plane would have been a total loss without Guthrie’s rescue efforts, I figure he owns it now. I nagged him to do some simulator time, which he did, probably an hour total.
The freeware RC plane simulator is dull as church. It’s not like a fun game with an airplane, but it does help with the basics, especially getting the hang of steering when the plane is coming right at you. It’s actually in some ways more difficult than flying the real plane, because the simulator plane is hard to see in context.
The weather was perfect for Guthrie’s first flight – very light, fairly steady breeze and lots of sunshine. I took a couple of circles around the field to trim the airplane up, then managed to snag the landing gear in some blackberries on approach. The plane was fine, but we lost a wheel in the thicket, so all subsequent flights were hand launched and landed in the grass. Hand launching is actually much easier than taking off from the ground, just keep your hands well away from the propeller. Once I was confident the plane was flying straight and level hands-off, I handed the controller to Guthrie and he flew from then on.
The takeaways from all this are that Guthrie clearly has amazing natural flying talent, and that the simulator really works. I got a Futaba “transmitter” box with a USB plug from the Goodwill for $8, and there are a few different free software options. Sadly, I couldn’t get anything to work with Linux (I think it can be done), but it works fine with Windows.
If you’re thinking of doing one of these planes, definitely get a simulator going. If you can fly the sim, you can fly the actual plane. Not that there won’t be crashes, but the happiness/frustration ratio will be much better.