| IKARUS ELECTRIC PICCOLO HELICOPTER |
RC Club: Fresh Start RC - Auburn, New York
Below are two short clips of our first successful attempts hovering an
electric Piccolo Eco helicopter. The flights occurred in the garage to
avoid the wind outside. Click on the links below to view the clips.
Although short, these clips are about 2 MB each so DSL and Cable Modem
users can download them in 10 to 20 seconds. Telephone dialup users will
probably have to wait more than 20 minutes to view them.
Files immediately below are in WMV format (for Windows based machines -
files are about 2 MB each):
PICCOLO (close shot in flight)
PICCOLO (further away with operator behind)
For those with machines unable to run files in WMV format, the files below
are in AVI format (about 6MB each):
PICCOLO (close shot in flight)
PICCOLO (further away with operator behind)
It took us quite some time to reach the stage you see above. We had tried flying the helicopter on a number of occasions without success. This was partly due to the fact that neither of us had ever flown a helicopter before and my RC airplane skills were mediocre at best.
I must note that at first we had some problems in that there did not appear
to be sufficient power to get off the ground, even after a full charge.
There was also a lot of vibration and the helicopter shook violently. We initially attributed the lack of
power to a bad battery pack and switched to another battery pack from a
small electric plane we had. It wasn't the same shape (8 batteries, two
batteries long, wide and deep), but with a few modifications to how it
sat below the helicopter it worked just fine (note that our helicopter
looks a little different due to the different battery pack).
We still had the vibration problem and there was now barely enough power
to get into the air. We narrowed the problem down to the alignment of the
flybar paddles that sit perpendicular to the main blades. If the flybar
paddles are not in the plane of the rotor blades you are in for trouble.
What appears to happen is that if you whack the rotor blades against anything,
the flybar paddles get knocked out of alignment with the blades (I would
hazard a guess that this is due to the blades, hinged at the central rotor,
spinning around the hinge and hitting the flybar paddles, knocking them
out of alignment).
Your flybar paddles have to appear as in the photograph above. Your flybar
control arms also have to be even with the plane of the rotor blades. Note
that the flybar control arms are in the proper position in the photograph
below (They are not askew, neither pushed up above nor below the plane
of the rotor).
What causes the bits described above to be out of alignment is that the flybar has has twisted in the screw mounts (see flybar and screws in the photograph above). This causes the flybar paddles and flybar control arms to be askew compared to the plane of the main rotor blades. To correct the problem, undo the two screws (seen above) and twist the flybar around so that everything comes back into alignment. Then do the screws back up.
If, while flying, you bump into something with the main rotor blades, you
may twist the flybar and you'll have to set it all back right again. After
a crash, you'll immediately know if you've twisted the flybar out of position
because you'll get violent shaking when you go to take off (and a noticeable
lack of power will exist). You can also twist the flybar out of position
by suddenly applying a lot of power when the blades are at a standstill
(the main blades can spin around and hit the flybar paddles). To avoid
this problem, slowly get the blades spinning from a dead stop (once they
get spinning you can apply all the power you want).
The only other notable mechanical problem we had with the helicopter was
caused by hard, pancake landings. We noticed that the ping-pong ball under
the landing gear would get bashed up into the battery, which would in turn
get bashed up into the large gear being driven by the motor. Although this
did not cause any permanent damage, it would drive the large gear up and
off the small gear on the motor.
We remedied this problem by sawing off the bottom of the ping-pong ball
under the main landing gear and adding larger, solid polystyrene balls
at the ends of the training rig (you can pick up these rigid polystyrene
balls at most craft stores). The resulting additional ground clearance
cured the problem.
Other modifications we made to the helicopter included replacing the shelf
at the front of the helicopter on which the controller sits (due to flight
damage) and rigging up some holders for our battery (again, as the battery
that came with our helicopter had problems, the battery you see above is
different from the one that came with your helicopter. The one we're using
is a different shape and an 8 cell 9.6 volt AAA 650 mAh NiMH battery -
works great).
The problems mentioned above are meant to describe the hiccups encountered
by two people new to helicopter flight. Overall, this is a well designed,
well manufactured helicopter. It has been remarkably forgiving in the limited
crashes we've had so far and I suspect the flybar alignment problem (mentioned
above) was probably intentionally designed that way to avoid permanent
damage. Things might get knocked out of alignment, but they generally don't
break (we did have to replace the carbon fiber tail boom spar after a rather
ugly incident).
Having said that, if you are new to radio controlled aircraft or helicopter
flying, you should not expect to power up this type of aircraft and be
flying it around your living room by lunchtime. Most RC flying has a learning
curve which will always begin with some rather unfortunate incidents. If
you are not willing to persevere with it (and that means putting a lot
of broken things back together) this may not be for you. I just fly these
things and don't build them or, more importantly, fix them. The work seen
above was all done by my father who (fortunately for me) has had the patience
to put back together some rather mangled aircraft.
If you are just starting to fly an electric helicopter (I can't speak for gas powered) I must point out several things. First, don't ever attempt to fly it if there is any wind. Even a two or three mile per hour wind, especially if it is gusty, will make flying a terrible challenge. My first successful hovering attempts occurred in a garage (in order to avoid the wind outside).
Secondly, when you try your first flights, your primary job is to trim
the helicopter. A helicopter, even slightly out of trim (especially the
tail boom), is next to impossible to fly. Take off and try to hover. If
the tail is rotating right or left, put it down and correct the trim. Take
off again and check it. If the same problem exists put it down and correct
the trim - and so on and so on. The most important trim to correct is the
tail boom. If the tail of your helicopter is rotating right or left you
must correct it. There is nothing more important than getting the tail
in trim and, although it would take about a page to explain why, you will
not be able to hover in any way until you correct this problem. Once that's
corrected move on to trimming forward and backwards and left and right.
Only attempt to hover at first with the front of the helicopter pointing
AWAY from you. Always stand behind the helicopter so the controls are in
the same orientation to where you are standing. If the helicopter drifts
right, then you correct by pushing the stick left. (If the helicopter is
pointing towards you, then the corrections you have to make are all opposite!)
When first attempting to hover do NOT attempt to hover in an exact spot.
Imagine a huge ten foot hoola hoop placed on the ground. Your job is just
to hover within the hoola hoop, despite the fact you are constantly drifting
around within it. That's easy, but the moment you try to stick the hover
to one exact spot you'll quickly get out of control (this is hard to explain
and you'll understand it when you try).
We bought the headinglock module (sometimes "heading lock module")
and had it in to start (the headinglock module is a tiny board you can
plug into the circuitry of the helicopter in about two seconds. It tries
to keep the helicopter pointing in the same direction.) As you should be
learning with no wind present, do NOT use this module. It may make learning
a lot harder as the onboard computer will fight with your control. This
unit may be very good when you are comfortable flying and a breeze is present,
but I haven't reached that stage yet. (If you fly in a breeze coming from
one direction a helicopter will act like a weathervane. In other words,
the helicopter will always turn so that it points into the wind. The headinglock
module exists to counteract this tendency and, if no wind is present, it
may be a hindrance to novice pilots).
Finally, I cheated and purchased a computer program, Realflight G2 lite
(about $100), and spent about 10 hours practicing with a helicopter on
the computer (note that G2 lite usually comes with a pretend RC transmitter
controller that you plug into the USB port as practice with a keyboard
or joystick would be pointless). For about the first hour I believed that
no normal human being could ever fly a helicopter, but slowly I made progress
and within several hours I could hover around. If you also decide to take
this route, turn off most of the obstacles on the ground so you can focus
on hovering and not avoiding fences, telephone poles and trees. I don't
honestly know whether I would have ever been able to fly a helicopter without
the computer practice beforehand. Having said that, I'm not sure at this
point whether the computer simulation will get you much beyond a hover
(although being able to hover is a HUGE step).
UPDATE: 8/4/2006
It's been about a year since I wrote the text above. After about a 10 month
break, I've been working hard on the simulator honing my skills and can
now fly the simulation well. We've had several attempts with the helicopter
and it is clear that my skills have significantly improved, but I am having
problems with the helicopter pointing towards me (I adjust to the reverse
controls easily on the simulator but I just don't seem to be able to relate
this to the actual helicopter). I have also found trimming the real helicopter
to be significantly more difficult than the simulator.
Anyway, if anyone is interested in just another hover sequence outside in high resoultion, here is an avi file which is 15Mb so only broadband user should attempt to view it (it will work on Windows Media Player or Real Player).
High Res Hovering
Brian Peace
Robert Peace
RC Club: Fresh Start RC - Auburn, New York
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