Hummingbird lift off problems
#1
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I just got a hummingbird setup
gws 4ch reciver
century mixerboard/speed control
century piezo gyro
gws transmitter
I'm having trouble when i start to lift off the heli wants to go backwards
i've adjusted & balanced evrything per directions can't seem to figure out why it wants to fly backwards
it takes almost all elevation trim to start to counteract but still not right any help would be much appreciated
gws 4ch reciver
century mixerboard/speed control
century piezo gyro
gws transmitter
I'm having trouble when i start to lift off the heli wants to go backwards
i've adjusted & balanced evrything per directions can't seem to figure out why it wants to fly backwards
it takes almost all elevation trim to start to counteract but still not right any help would be much appreciated
#2
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Also i'm looking for a good high speed micro servo for my hummingbird any suggestions.
it seems to me that the servos i have now are slow to respond-takes a while for the heli to act as far as the aleroin & elevator ie........the two servos
any suggestions or ideas ??????????????
it seems to me that the servos i have now are slow to respond-takes a while for the heli to act as far as the aleroin & elevator ie........the two servos
any suggestions or ideas ??????????????
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you said you've balanced everything already, but did you try to hold the heli by the flybar and see if the heli is level (with batt pack installed). The flybar shoudl be perpendicular to the tail boom when doing this test.
Also the swash should be level. I have a Dragonfly and my forward cyclic trim also needs to be all the way up, but that seems enough for me to steady the heli. I've tried to move the arm on the servo, one click up, but then its too much forward cyclic!
BTW. Is your heli responsive to cyclic controls when you throttle up JUST making the heli light on its skids. you should be able to direct the heli which ever direction you want at this point(mod the ground effects), heli skidding along the floor(not on carpet!)
If not, your blades might be over pitched.
As for servo response, I do not have the century servos so I cannot comment, but the gws servos I have seem responsive enough....doesn't help you though huh?? :-) Perhaps someone else can comment on this...
Remember that heli response is 90 degrees late anyway.
Also the swash should be level. I have a Dragonfly and my forward cyclic trim also needs to be all the way up, but that seems enough for me to steady the heli. I've tried to move the arm on the servo, one click up, but then its too much forward cyclic!
BTW. Is your heli responsive to cyclic controls when you throttle up JUST making the heli light on its skids. you should be able to direct the heli which ever direction you want at this point(mod the ground effects), heli skidding along the floor(not on carpet!)
If not, your blades might be over pitched.
As for servo response, I do not have the century servos so I cannot comment, but the gws servos I have seem responsive enough....doesn't help you though huh?? :-) Perhaps someone else can comment on this...
Remember that heli response is 90 degrees late anyway.
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I agree with dragon dude, check your pitch.. also, you can trim your rotors a little to give you better head speed. Check out my website for all the details on balancing and trimming. (It might give you a couple other ideas to check out your bird.)
http://home.earthlink.net/~ibsniper
Servos, your stock servos really should have more than enough speed for you. I'd almost bet it's pilot error. Get it checked out by your LHS (local hobby store). I've worked with dozens of the HB's and that really the first time I've heard that the servo response time was too slow.
(Not saying your wrong.. it's just not common)
Happy flying!!
http://home.earthlink.net/~ibsniper
Servos, your stock servos really should have more than enough speed for you. I'd almost bet it's pilot error. Get it checked out by your LHS (local hobby store). I've worked with dozens of the HB's and that really the first time I've heard that the servo response time was too slow.
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Happy flying!!
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I also found that exact same problem with my HB when i then moved the server horn 1 click up it then required me to have the trim all the way down to counteract to me it seemed as though it was the coneection rods from servo to swash were a tiny bit to short for perfect trimming.
After a good number of flights i found that it was more of my piloting error that was causing it just the weight of my thumbs on the stick was enough to move it and cause the constant rearward movement,
I also found this site [link=http://www.electricmicro.com/index.html]Eliectricmirco[/link] and did the modification that is found on the upgrades link for removing the rubber tube from around the main shaft which helped me loads to gain a much better hover.
Hope this helps
After a good number of flights i found that it was more of my piloting error that was causing it just the weight of my thumbs on the stick was enough to move it and cause the constant rearward movement,
I also found this site [link=http://www.electricmicro.com/index.html]Eliectricmirco[/link] and did the modification that is found on the upgrades link for removing the rubber tube from around the main shaft which helped me loads to gain a much better hover.
Hope this helps
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I had the same problem. Everything was checked and running fine, that's why i was confused. But then I did some checks and observed the main blades (coz i have the stock main blades) and saw the problem.
In my case, the problem was that the main blade had so much elasticity, that at low rpm, the blade would have the pitch that was suppose to lift the heli to the air,.... but at high rpm, it flexed so much (it straighten out) that the pitch became so much lesser and didn't have enough pitch to lift the heli.
At first, i tried to fix it by placing a small metal plate which is bent following the countour of the blade in width (find the right spot so it can support most of the blade because the plate can be too wide/big to reduce weight) so that in high rpm, the blade wouldn't straighten out because it is supported by that plate. This solved the problem, but it reduces flight time because of the weight. Now i've detached the small plate and tried to make the blade more rigid but less weight. If this works and someone has the same problem i'll tell them how, but now i'm still testing it. The easiest solution of course is to make or buy better blades.
Sorry for the long answer!
In my case, the problem was that the main blade had so much elasticity, that at low rpm, the blade would have the pitch that was suppose to lift the heli to the air,.... but at high rpm, it flexed so much (it straighten out) that the pitch became so much lesser and didn't have enough pitch to lift the heli.
At first, i tried to fix it by placing a small metal plate which is bent following the countour of the blade in width (find the right spot so it can support most of the blade because the plate can be too wide/big to reduce weight) so that in high rpm, the blade wouldn't straighten out because it is supported by that plate. This solved the problem, but it reduces flight time because of the weight. Now i've detached the small plate and tried to make the blade more rigid but less weight. If this works and someone has the same problem i'll tell them how, but now i'm still testing it. The easiest solution of course is to make or buy better blades.
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Thanks guys for all the input.
Dragon-dude heli is balance and does respond to cyclic controls on the floor abit difficult to trim it so it doesn't slide. and as far as the servos go it just seems like there's a bit of a delayed reaction maybe its me??
I agree with arceye that the rods are a bit short from the servos to the swash plate.maybe this is a reason why the servos seem slow to me or dont have the reaction i expect. the swash plate is level as much as parts will allow
and the stock blades are questionable anyone have any recomedations on blades
all in all having fun with heli would just like to get it to hover more stable and react better any ideas or thoughts would be helpful
Dragon-dude heli is balance and does respond to cyclic controls on the floor abit difficult to trim it so it doesn't slide. and as far as the servos go it just seems like there's a bit of a delayed reaction maybe its me??
I agree with arceye that the rods are a bit short from the servos to the swash plate.maybe this is a reason why the servos seem slow to me or dont have the reaction i expect. the swash plate is level as much as parts will allow
and the stock blades are questionable anyone have any recomedations on blades
all in all having fun with heli would just like to get it to hover more stable and react better any ideas or thoughts would be helpful
#8
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One thing to check, are your servos reversed? If you push forward (up) on your stick, the swash plate shold pitch forward.