low Rx battery voltage and =POW=
04-27-2004, 11:03 PM
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low Rx battery voltage and =POW=
I guess it was inevitable, what with the increasing air temps and my increasing comfort on the sticks..... I was flying my third flight after checking the voltage on my Rx (it was 5.10 when last checked) when on takeoff the motor jumped to full throttle and the rudder and ailerons locked in full left turn and elevator in full up position. No control inputs made any difference over the final 3 or 4 seconds. Time stood still as I watched my Tiger 2 do a slow awkward dance and roll/loop over and hit spinner first into ole mother Earth. Sixth or seventh flight of the day on this bird -- I'd never had that many on her in one session before. The old timer flying next to me helped me pick up the pieces and asked me one question: Did you check receiver voltage before that last flight? When we got the pile back to the hanger I checked the reciever voltage for fun: just at 4.75 under load.
Lesson learned? The voltmeter doesn't do much good stashed in the toolbox.
Now I get to practice cutting and gluing again. At least the servos and radio equipment and motor came through in decent shape.
Any rules of thumb on Rx voltage limits/battery usage?
S
Lesson learned? The voltmeter doesn't do much good stashed in the toolbox.
Now I get to practice cutting and gluing again. At least the servos and radio equipment and motor came through in decent shape.
Any rules of thumb on Rx voltage limits/battery usage?
S
04-27-2004, 11:45 PM
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RE: low Rx battery voltage and =POW=
[&o]Sorry to hear about the need for more glue. I have a "Volt Spy" mounted on the aircraft where I can see it when I waggle the sticks. This way I can check everything is Ok when I am taxy out to take off. I had a similar experience to yourself. For less than $20.00 it is good insurance. I'm sure there are plenty of similar on board visual battery strength indicators available.
Good luck with the repairs.
Cheers,
Colin
Good luck with the repairs.
Cheers,
Colin
05-02-2004, 11:38 PM
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RE: low Rx battery voltage and =POW=
My rule of thumb is check it when I get to the field, fly two flights, check it, peak charge it, check it, fly two more flights and do it all again. Those being about 7 minute flights on a 600mah pack.
05-05-2004, 07:22 PM
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RE: low Rx battery voltage and =POW=
SDC,
I lost a plane a few months ago to low battery voltage on the standard 600mah pack that came with the radio. Only two flights, but lots of time screwing around trying to get the engine to idle right.
Learned my lesson: I replaced all my packs with 1650 NiMH. They are still A-size cells, still essentially the same weight, but almost 3X the capacity. I can pretty much fly all day, but I still check the voltage periodically. Some of the guys I fly with use 5-cell packs (i.e. 6 volt nominal) which gives you both more servo speed and more voltage leeway.
Greg
I lost a plane a few months ago to low battery voltage on the standard 600mah pack that came with the radio. Only two flights, but lots of time screwing around trying to get the engine to idle right.
Learned my lesson: I replaced all my packs with 1650 NiMH. They are still A-size cells, still essentially the same weight, but almost 3X the capacity. I can pretty much fly all day, but I still check the voltage periodically. Some of the guys I fly with use 5-cell packs (i.e. 6 volt nominal) which gives you both more servo speed and more voltage leeway.
Greg
05-05-2004, 09:16 PM
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RE: low Rx battery voltage and =POW=
Guys --
thanks for your responses. Needless to say I'm learning more about batteries and electrical systems than I ever thought possible. Hopefully this is one mistake I'll not make again. I wonder which lesson is next?
S
thanks for your responses. Needless to say I'm learning more about batteries and electrical systems than I ever thought possible. Hopefully this is one mistake I'll not make again. I wonder which lesson is next?
S
05-09-2004, 01:54 PM
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RE: low Rx battery voltage and =POW=
Get a field charger and charge it before each days flying.
If you fly more than 4-5 times then recharge the pack.
I use an on-board monitor on all my planes just to know where I am.
It is not as good as a ESV check before each flight, but it is better than nothing.
If you fly more than 4-5 times then recharge the pack.
I use an on-board monitor on all my planes just to know where I am.
It is not as good as a ESV check before each flight, but it is better than nothing.
ORIGINAL: sdc
I guess it was inevitable, what with the increasing air temps and my increasing comfort on the sticks..... I was flying my third flight after checking the voltage on my Rx (it was 5.10 when last checked) when on takeoff the motor jumped to full throttle and the rudder and ailerons locked in full left turn and elevator in full up position. No control inputs made any difference over the final 3 or 4 seconds. Time stood still as I watched my Tiger 2 do a slow awkward dance and roll/loop over and hit spinner first into ole mother Earth. Sixth or seventh flight of the day on this bird -- I'd never had that many on her in one session before. The old timer flying next to me helped me pick up the pieces and asked me one question: Did you check receiver voltage before that last flight? When we got the pile back to the hanger I checked the reciever voltage for fun: just at 4.75 under load.
Lesson learned? The voltmeter doesn't do much good stashed in the toolbox.
Now I get to practice cutting and gluing again. At least the servos and radio equipment and motor came through in decent shape.
Any rules of thumb on Rx voltage limits/battery usage?
S
I guess it was inevitable, what with the increasing air temps and my increasing comfort on the sticks..... I was flying my third flight after checking the voltage on my Rx (it was 5.10 when last checked) when on takeoff the motor jumped to full throttle and the rudder and ailerons locked in full left turn and elevator in full up position. No control inputs made any difference over the final 3 or 4 seconds. Time stood still as I watched my Tiger 2 do a slow awkward dance and roll/loop over and hit spinner first into ole mother Earth. Sixth or seventh flight of the day on this bird -- I'd never had that many on her in one session before. The old timer flying next to me helped me pick up the pieces and asked me one question: Did you check receiver voltage before that last flight? When we got the pile back to the hanger I checked the reciever voltage for fun: just at 4.75 under load.
Lesson learned? The voltmeter doesn't do much good stashed in the toolbox.
Now I get to practice cutting and gluing again. At least the servos and radio equipment and motor came through in decent shape.
Any rules of thumb on Rx voltage limits/battery usage?
S
05-10-2004, 09:33 AM
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RE: low Rx battery voltage and =POW=
Volt Watch units are available from Tower Hobbies online at about US$11.00. They plug into any free receiver channel and mount flush using provided double-sided tape or with small screws. After my crash, I will be using these in most of my planes from here on out....
By the way, repairs and replacements almost complete on the crashed Tiger 2. Hope to by flying again this coming weekend.
S
By the way, repairs and replacements almost complete on the crashed Tiger 2. Hope to by flying again this coming weekend.
S
05-10-2004, 01:27 PM
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RE: low Rx battery voltage and =POW=
Hey guys, MAXX products has a voltwatch built right into the charge switch. Slick! Bout $ 25 bucks and eliminates the extra voltwatch. Check the web. 
