OldRCer
Heliman
Location: Southern California, Orange County
| Hi all
Well, I can certainly relate to the stuff I have been reading here.
I have a Piccolo plus many "Weird" helis and flying machines.
I even had an electric "tail rotor" motor (of my own design) on an early Ishimasa Skylark electric heli years ago. A picture of it was published in RCM magazine (1980)
I remember the problems too. First, no gyros for electrics and no piezo’s for sure.
I used a Victor Engineering speed control to control the tail and one to control the main motors (TWO 540 Cans) It all worked extremely well for the time, but it was a handful.
When I gave full power to the main motor, the tail would not spin fast enough to hold.
When I gave full tail rotor power, it would not have enough power to lift. It was a real balancing act.
Most Skylarks became tethered. They sold a 21 foot tether made out of silicone wires that wouldnt melt with the kit. Condor Hobbies used to import them.
Alexander Van de Rostyne (Inventor of the Piccolo in Belgium) used this tail rotor motor idea and perfected it with the electronics of the day. He and I are friends and I know of his accomplisments.
SO....Now I decided to go buy a Humming bird.
Well honestly, I tried everything I could think of and I could never get mine off the ground either!!
I have read these newsgroups and comments and all about the guy whos hummingbird planted itself to the ceiling when he walked away!
WOW! What was I doing wrong, I asked myself?
Finally, I gave up and due to pride of being quite a bit familiar with helicopters over the years and experienced enough to know not to KICK a gas one when it is flying,
(which I did to save a crowd of people and also broke all the bones in my foot) I reluctanly went down to my local Hobby shop and asked for help.
Of course they all tried to fly it and it wouldn't go higher than 5 inches either...(Smugly said)
Well guess what? My motor was bad from the Start. They put in the Hummingbird upgrade motor and before you knew it, I was flying it around in the hobby shop. (Gyro Hobbies-Lake Forest, Ca)
So now I have this neat little bird that will fly a long time and quite nicely, as long as you are inside.
No matter what I've read here, I am sure that I can fly it around in forward flight with no problem....right?
Wrong again!
For some reason, If any lift gets under the main rotor, the heli begins flying backwards and trying to recover from any more than a 40 degree nose up attitude is futile! A fast U-Turn (stall turn) is the best recovery.
Otherwise, I have noticed a phenonom with this tail rotor motor combo from my early years too.
When the Heli gets in this attitude, and with my correcting , the tail rotor really spins up.
It actually creates a Vacuum that the main rotor and heli falls into.
Of course this is wild, eh?
I keep thinking it needs more pitch forward, etc, but it is too far now.
So, I moved my battery to the front as far as is would go, I put the gyro on the front, I put a boom antenna out the front. I put solder around the tip (see picture) and balance it.
Everything I could think of to get the heli to hang slightly nose forward.
Well this worked good and my Swashplate is fairly level, so the controls are more symetrical.
I also cut a slot for the elevator servo arm in the Mixer case, (its empty anyway and doesnt even need the lid) so I could use a bigger arm without it hitting. Then I reduced my servo endpoints. I siliconed the servos tight and have great control.
BUT.....It still falls into that vacuum without much warning if the winds picks up a bit.
Gee, I'm really rambling and am sorry to go on so long. I know lots of my questions can be answered here and I have enjoyed all your comments. I am glad I am not the only one with some unique problems.
In summary, I would never had suspected a bad motor from the start, and certainly was embarrased to take it back to the hobby shop to complain.
But, I did and it turned out that even brand new sometimes is not.
Gyro Hobbies replaced the Motor free and I was pleased. I have flown this little bird inside many of my customers businesses and of course they are all impressed. I like it alot.
I really like the litte Hummingbird. I just wanted to hear any thoughts on my Tail Rotor Vacuum theory.
I also slipped some silicone rubber tubing on the landing gear to keep it from sliding off the landing zones that I fly on. I am a traveling salesman and love to fly inside some of my big dealers. They have lots of room . It also gives them lots to talk about after I leave.
Hats off to Century. From what I see and read, they seem committed. And you know, when you fly Helicopters, you have to be committed....somewhere anyway ..
Ps, What is the life expectancy of the brushless motors? It should be forever, right?
When it is too windy, I fly inside the trunk of my PT Cruiser to demo to my clients.
I sent a picture of me flying it in the trunk. I
t also shows also my Weight mods. I sent it to electricmicro.com but do not know if it is posted yet.
If you tell me where to send a picture of my modifications, so it can be posted somewhere else, I would be happy too.
Sorry for the rambling....Happy flying....
Dave Herbert
OldRCer
AMA 8221 |
