Silverburn
Member
Is one of your motor arms twisted? Or is your CoG off?
Fast ascent causes quad to bank and pitch. Need help.
- Thread starter Maverick
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Maverick
Member
No, all motors are perfectly square, and CoG is spot on.
Like I said, it's fixed now, and flying perfect. Rock solid. I just can't believe the jump from 3S to 4S made all the difference...
Hmmm, not all that surprising really if you think about it. If it's got a fairly high AUW your motors will need more static thrust to compensate for the addtional weight and the wattage that your rig will need to be able to consume is going to ramp up. The static thrust that you'll need to lift the extra weight will also mean that your peak amps are going to climb significantly as you lift off, which may mean that it's a little harsh for the 3S packs. 3S packs just won't have enough punch to allow your rig to compensate quickly enough.
Have you kept a check on the variance of your pack voltages from when they're freshly charged, during take-off, then into a hover, and watched as you progress from hover to forward flight at varying speeds and rates of climb? It's something I've been reviewing quite a lot lately as I log the effects of different flying styles, altitudes, forward speed, etc, to allow me to better predict flight duration. I've been flying my F550 with 4S 6100 mAh and when you're watching the voltage differences from hovering to forward flight can be pretty revealing. If you really want to punish your packs you just go wide open throttle, straight up, to get all motors smashing up your pack as hard as they collectively can - which is what you've been doing when you experience those skewed fast climb-outs.
As a side note, I generally try and record as many of my flights as I can. I have a dual-diversity receiver with two video outputs - one goes to my goggles the other goes to a hand-held PVR which records onto a MicroSD card. After a days flying I watch the captured OSD video and log the max height, max speed, max distance and voltages from each flight, as well as noting the packs I've used. I number all my packs and some are 5000 mah and some are 6100 mah. I also record the final voltage and then record how much goes back in when I recharge them. I know it all sounds a bit anal, but like I said it's very revealing and you very quickly get a feel for just how hard your packs are working under different conditions.
I've not flown for a few weeks, either due to appauling whether or I've been busy with other things, and the temperature this week (just north of London) compared to only three weeks ago is radically different and I know the cold air is going to start shortening flight times very noticeably. My summer-flying-weary packs will start to see a performance hit I'm sure, and I'll probably buy a complete new set of packs next spring. In reality cold fingers will also play a part in flight duration too, so no point spending money on new packs right now.
Maverick
Member
Hey Rainman,
Thanks for your explanation!
Up until now, I haven't been logging pack voltages/IR/mAh etc, but I'm going to start.
All I know is, when I take off on a fully charged 3S pack, the line loss voltage is about 0.6v when it's in a hover.
AUW was 1.969kgs, but since I replaced my AeroXcraft servo-driven gimbal and Hero 2, with a Tarot T-2D BLG and Hero 3-BE, and my 3S 5000mAh pack with a 10gram lighter 4S 4250mAh pack, mu new AUW is now 1.83kgs (139grams less)
Thanks for your explanation!
Up until now, I haven't been logging pack voltages/IR/mAh etc, but I'm going to start.
All I know is, when I take off on a fully charged 3S pack, the line loss voltage is about 0.6v when it's in a hover.
AUW was 1.969kgs, but since I replaced my AeroXcraft servo-driven gimbal and Hero 2, with a Tarot T-2D BLG and Hero 3-BE, and my 3S 5000mAh pack with a 10gram lighter 4S 4250mAh pack, mu new AUW is now 1.83kgs (139grams less)
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