Flying the Heli Outside
Sometimes it is just too nice outside to be practicing RC Heli flying indoors. One problem with micro helis is that they are not designed to fly in any wind ...
Time to get out!
After a few days of flying the helicopter in my parking garage, I was starting to feel a little too constrained within the tight confines of the cement garage walls. Being a sunny, calm day I decided to try my hand at outdoor flight for the first time.
From postings elsewhere on the web, I had understood that the Blade CP Pro, being a micro-sized heli, is intended to fly in zero wind. It is apparently not designed to fly in wind, presumably due to its tiny size and limited weight (298 g). But, seeing that the day appeared nice and calm with no visible wind, I thought I'd give it a try anyway.
Nearby, there is a large grassy courtyard that I can use for flying, with no obstructions for at least 50 feet! Unfortunately, the grass is long enough to interfere with the tail rotor (as the tail rotor vertical rod sinks down).
I faced a similar problem indoors (with the tail support rod digging into the carpet), and I simply placed some wrapping paper (suitably weighed down at the corners) for my start. In the grass, I tried to pat down the grass near the tail rotor and then take off quickly vertically without drifting first. It seemed to work OK, but was less than ideal. Later on, I discovered that a floor mat did the trick nicely.
Beware the Breezes!
Given the greater space to work in, I found myself more confident in keeping the heli at an altitude of about 5', so that it was well out of ground effect, but not high enough that my perspective changed from "controlling from above" to "controlling from below". I did notice, though, that the occasional slight breeze did have a moderate impact on the stability of the hover.
In one case, a breeze suddenly caused a burst of lift under the heli, which raised it up about 5 feet in a matter of about a second or two, with no change in my input to collective pitch / throttle. As a beginner, this can be a bit disconcerting! I have since read a few stories on the internet about other people who have had their heli carried up 20' or more. In one case, a guy was flying his heli at night in an illuminated driveway -- a gust of wind carried his heli far out of sight into the dark night air, followed by the sound of a heli crashing to the ground in the distance!
First Blade Strike!
Up until now, I have never had any accident with the heli. Looking at all the wreckages posted in YouTube videos of "rc heli crash"I have been extremely cautious with my training! While I've been careful, I'm continually trying to push myself a little bit each time I practice. Of course this means that eventually the crash-free streak will come to an end!
Sure enough, I found myself getting a little out of control (side-in) and wanted to bring the heli back down onto the skids. Well, at the moment that the training gear touched the ground, the heli was still moving sideways at walking pace.
One of the rods sticking out of the corner of the landing gear eventually caught a tuft of grass and I saw the heli start to tip over. Oh no! I quickly dropped the throttle, but it was too late. The long blades reached the ground and made a loud clapping sound before the heli came to a rest on its side. The blades had collapsed so that they were both pointing in the same direction (presumably the design of the blade holders to release some of the energy of a blade strike). I wiped off the grass stains on one of the blades, looked for visible damage and saw none. Setting the heli back on the ground, I took off again, just to ensure that everything seemed to fly OK still.
It was not until later that I discovered that this little tumble actually caused a rotation and misalignment of the flybar. The paddles had rotated a bit as well as shifted along their longitudinal axis (since I had removed the inner flybar collar and used them as outer weights!). This caused a bit of an imbalance in the rotor head, which I later corrected when I rebalanced the flybar (while attaching new flybar collar weights).