drops while hovering
#2
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From: Albuquerque,
NM
ORIGINAL: jfast
any ideas on why my heli drops while in a steady hover? it will do this even inside with no wind.
trex 450 se v2
any ideas on why my heli drops while in a steady hover? it will do this even inside with no wind.
trex 450 se v2
Radio glitch?
ESC cutting out?
-Dave
#4
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From: houston,
TX
rpms , seem to stay steady, so i don't think it is a motor or battery related issue, i heard something somewhere, poss pitch curve issue?
#5
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From: Albuquerque,
NM
ORIGINAL: jfast
rpms , seem to stay steady, so i don't think it is a motor or battery related issue, i heard something somewhere, poss pitch curve issue?
rpms , seem to stay steady, so i don't think it is a motor or battery related issue, i heard something somewhere, poss pitch curve issue?
(and it's something that's easy to check).
Flying Foot Doc, Go Gators!
-Dave
#6
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From: Tucson,
AZ
I have a similar problem. Here is the senario: Trex 450SE V2/CC PHX45a esc/Align 430XL/2200mah 3s 25C lipo/HS65MG on swash/Futaba 9650 tail/GY401/Spektrum AR7000 w/CC 10a BEC/DX7 Radio.
I only do sport flying, no 3D. All was fine until one day I was not able to bring to a hover. RPM kept cutting back. Had to make major throttle changes on radio from liniar to 0/45/75/95/100. Now I get it to hover and then the RPM drops out. Have to make quick & drastic changes with the throttle stick to maintain a hover but whatever I maintain in this fashion only lasts seconds before another RPM drop.
In an attempt to find the problem I went through the process of elimination. Changed motor, changed esc, changed battery and changed receiver but the problem continues. So the only thing I haven't done was try another radio. My radio works fine with another Trex 450 and an airplane.
Well, what's the verdict? I ran out of idea's and I'm not an electrical engineer.
I only do sport flying, no 3D. All was fine until one day I was not able to bring to a hover. RPM kept cutting back. Had to make major throttle changes on radio from liniar to 0/45/75/95/100. Now I get it to hover and then the RPM drops out. Have to make quick & drastic changes with the throttle stick to maintain a hover but whatever I maintain in this fashion only lasts seconds before another RPM drop.
In an attempt to find the problem I went through the process of elimination. Changed motor, changed esc, changed battery and changed receiver but the problem continues. So the only thing I haven't done was try another radio. My radio works fine with another Trex 450 and an airplane.
Well, what's the verdict? I ran out of idea's and I'm not an electrical engineer.
#8
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From: Tucson,
AZ
Thanks for suggestion but I bought some silicone spray and sprayed the belt. Problem still present. ?????
Now I'm having trouble getting it off the ground.
Now I'm having trouble getting it off the ground.
#10
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From: Albuquerque,
NM
ORIGINAL: squawk7700
IChanged motor, changed esc, changed battery and changed receiver but the problem continues. So the only thing I haven't done was try another radio. My radio works fine with another Trex 450 and an airplane.
IChanged motor, changed esc, changed battery and changed receiver but the problem continues. So the only thing I haven't done was try another radio. My radio works fine with another Trex 450 and an airplane.
-Dave
#11
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From: houston,
TX
well we fixed our problem, found 2 issues not sure which one fixed the issue of the dropping while hovering, i found my fly bar was slightly bent, also noticed that my esc was set to gov. mode and high timing ,
#12
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From: Tucson,
AZ
I really don't want to move stuff between my two Trex's because one is in a fuse with some different electrics. Checked the esc (which I don't use gov mode). In fact as mentioned, I replaced the esc and reprogramed it for the heli. Flybar is new along with the head and rotor system. Thinking of going into my LHS and ask them cause I am baffled. I even tried copying all my settings into another channel of my radio. Not sure if the timing is going to do anything but I haven't done anything with that at this point.
#13
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From: Newark, CA
I have the same problem with my T-rex 450. I found the battery is bad, or insufficient discharge. IT shut off the receiver, and the heli just fall straigth to the ground. You probably notice the tail start swaging before the receiver shut off.
#14
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From: Tucson,
AZ
asianrider, thanks for the suggestion. I'm not sure if that would be the problem. I've tried three other batteries that I know were good. Taking it to my LHS in the morning.
#15
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From: richmond, CA
I'm still working on mine also, it drop while in hover, head speed okey, if heli drop i just throttle it up, i check -/+ pitch, they are okey, it's -/+10. servo arm center at mid stick, battery are also okey as i use it on my other heli. i'm using airtronics rds8000 on my 450 rex.
#16
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From: Tucson,
AZ
Ybenjulkay,
How long will your heli hover before it drops? How much throttle do you input to get it back to the altitude from where it dropped? Did you mean that your headspeed remained the same when your heli drops or does the headspeed drop too?
Didn't make it the my LHS today, I'll try tomorrow. Meanwhile, I'm thinking about my next alternative. Maybe I didn't spray enough silicone on the tail drive belt, who knows.
How long will your heli hover before it drops? How much throttle do you input to get it back to the altitude from where it dropped? Did you mean that your headspeed remained the same when your heli drops or does the headspeed drop too?
Didn't make it the my LHS today, I'll try tomorrow. Meanwhile, I'm thinking about my next alternative. Maybe I didn't spray enough silicone on the tail drive belt, who knows.
#17
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From: richmond, CA
It hover 5-10 second then it drop and I just add a little throttle. Head speed, too hard to tell coz when i replace the main gear an hr a ago (I went to lhs to get the main gear)as i found some of the teeth on the main gear are round off, after a test fly it hover better that before, i believe it loosing head speed a little on hover due to round off gears. also found some binding on one of the blade grip one side is free when changing pitch, the other one, not realy that free maybe coz of thread lock on the screw where the thrush bearing goes so I just add a little oil in it, what's the best oil I could use for this for less static, right now i use turbine lubricating oil to free it.
#18
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From: richmond, CA
I edit the other one
ORIGINAL: Ybenjulkay2x
It hover 5-10 second then it drop and I just add a little throttle. Head speed, too hard to tell the sound of the motor and blade are the same but i realize/found something on the main gear, i replace the main gear an hr a ago (I went to lhs to get the main gear)as i found some of the teeth on the main gear are round off, after a test fly it hover better that before, i believe it loosing head speed a little on hover due to round off gears. also found some binding on one of the blade grip one side is free when changing pitch, the other one, not realy that free maybe coz of thread lock on the screw where the thrush bearing goes so I just add a little oil in it, what's the best oil I could use for this for less static, right now i use turbine lubricating oil to free it.
It hover 5-10 second then it drop and I just add a little throttle. Head speed, too hard to tell the sound of the motor and blade are the same but i realize/found something on the main gear, i replace the main gear an hr a ago (I went to lhs to get the main gear)as i found some of the teeth on the main gear are round off, after a test fly it hover better that before, i believe it loosing head speed a little on hover due to round off gears. also found some binding on one of the blade grip one side is free when changing pitch, the other one, not realy that free maybe coz of thread lock on the screw where the thrush bearing goes so I just add a little oil in it, what's the best oil I could use for this for less static, right now i use turbine lubricating oil to free it.
#20
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From: richmond, CA
I'm flying my heli outside parking lot while no cars around calm wind. On the 500 it flies okey , the 450 flies okey now after i replace the main gear and lube the blade grip bearing. I'll test it latter when there is wind also.
#21
I'm talking about how high up off the ground are you flying? Are we talking 1-3 feet (ground effect will do weird things to the heli) or are you shoulder high. How high you hover will have an effect on the helicopters flight.
#22
ORIGINAL: squawk7700
I have a similar problem. Here is the senario: Trex 450SE V2/CC PHX45a esc/Align 430XL/2200mah 3s 25C lipo/HS65MG on swash/Futaba 9650 tail/GY401/Spektrum AR7000 w/CC 10a BEC/DX7 Radio.
I only do sport flying, no 3D. All was fine until one day I was not able to bring to a hover. RPM kept cutting back. Had to make major throttle changes on radio from liniar to 0/45/75/95/100. Now I get it to hover and then the RPM drops out. Have to make quick & drastic changes with the throttle stick to maintain a hover but whatever I maintain in this fashion only lasts seconds before another RPM drop.
In an attempt to find the problem I went through the process of elimination. Changed motor, changed esc, changed battery and changed receiver but the problem continues. So the only thing I haven't done was try another radio. My radio works fine with another Trex 450 and an airplane.
Well, what's the verdict? I ran out of idea's and I'm not an electrical engineer.
I have a similar problem. Here is the senario: Trex 450SE V2/CC PHX45a esc/Align 430XL/2200mah 3s 25C lipo/HS65MG on swash/Futaba 9650 tail/GY401/Spektrum AR7000 w/CC 10a BEC/DX7 Radio.
I only do sport flying, no 3D. All was fine until one day I was not able to bring to a hover. RPM kept cutting back. Had to make major throttle changes on radio from liniar to 0/45/75/95/100. Now I get it to hover and then the RPM drops out. Have to make quick & drastic changes with the throttle stick to maintain a hover but whatever I maintain in this fashion only lasts seconds before another RPM drop.
In an attempt to find the problem I went through the process of elimination. Changed motor, changed esc, changed battery and changed receiver but the problem continues. So the only thing I haven't done was try another radio. My radio works fine with another Trex 450 and an airplane.
Well, what's the verdict? I ran out of idea's and I'm not an electrical engineer.
#23
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From: Northern Occupied Mexico,
CA
Maybe not the cause but an interesting read http://www.heli-chair.com/aerodynamics_104.html
#24
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From: Tucson,
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I believe now that it's going to be my esc. I tried going back to the older firmware to reprogram my esc and now I can reset my throttle to linear and can start hovering for 5-10 seconds before it drops again. So I'm getting closer to fixing this problem. Hey Baurwin, what is LVC and what did you do to fix your problem?
#25
ORIGINAL: squawk7700
I believe now that it's going to be my esc. I tried going back to the older firmware to reprogram my esc and now I can reset my throttle to linear and can start hovering for 5-10 seconds before it drops again. So I'm getting closer to fixing this problem. Hey Baurwin, what is LVC and what did you do to fix your problem?
I believe now that it's going to be my esc. I tried going back to the older firmware to reprogram my esc and now I can reset my throttle to linear and can start hovering for 5-10 seconds before it drops again. So I'm getting closer to fixing this problem. Hey Baurwin, what is LVC and what did you do to fix your problem?
i cant remember for certaing what my problem was, but it sounds exactly the same. it would hover for about 15 sec then i would lose the headspeed and it would come down. it was definately in the esc though. i wanna say it was the lvc setting, but may have been one of the other settings...??
it just sounds like the lvc, so thats where i would look first.



