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dotyj
07-29-2007, 07:18 AM
That's right. I didn't crash my Heli-Max Axe today while practicing. I had a few "OH CRUD!!" moments and three landings hard enough to pop the training gear off, but not one bent, broken, or mis-aligned part in the run.

I got the chance to see just how long a lipo will last too since I'd recently purchased a lipo battery for my Axe. I like it. The lipo gave me so much time to practice that by the end of the battery I was more than ready to call it a day.

Also, I discovered a pychological issue. At one point I ended up flying over my room mate's car, a very nice looking Lincoln Mark IV (I think). Strangely enough it was more difficult to hover over the car than it was to hover over the driveway. Perhaps because of the increased cost to crash ratio? I was delighted to push the heli a bit to the northeast back over the driveway.

How did I end up hovering over the car? Good question. I wanted to land in the grass in front of the house just for kicks but chickened out when I flew over the car instead of around the car as I had planned.

Anyway, my hover times were easily 30 seconds, maybe more. I found it impossible to actually time myself since everytime I started counting up seconds I found it difficult to concentrate on flying. I guess I'm not that comfortable yet with hovering.

CHELLIE
07-29-2007, 08:01 AM
Hi Dotyj :) lipos are nice Huh :) I but a 2200mah 11.1 v lipo in my Shogun v2 with a 4200kv outrunner in it, and it seemed like I was flying it around for about 30 mins, it wore me out :) your doing great, Chellie

HX3D014
07-29-2007, 08:19 AM
That's right. I didn't crash my Heli-Max Axe today while practicing. I had a few "OH CRUD!!" moments and three landings hard enough to pop the training gear off, but not one bent, broken, or mis-aligned part in the run.

I got the chance to see just how long a lipo will last too since I'd recently purchased a lipo battery for my Axe. I like it. The lipo gave me so much time to practice that by the end of the battery I was more than ready to call it a day.

Also, I discovered a pychological issue. At one point I ended up flying over my room mate's car, a very nice looking Lincoln Mark IV (I think). Strangely enough it was more difficult to hover over the car than it was to hover over the driveway. Perhaps because of the increased cost to crash ratio? I was delighted to push the heli a bit to the northeast back over the driveway.

How did I end up hovering over the car? Good question. I wanted to land in the grass in front of the house just for kicks but chickened out when I flew over the car instead of around the car as I had planned.

Anyway, my hover times were easily 30 seconds, maybe more. I found it impossible to actually time myself since everytime I started counting up seconds I found it difficult to concentrate on flying. I guess I'm not that comfortable yet with hovering.
there may well be two other reasons.
1/ You have change your angle of View. IE you are now more level with it instead of it being Below you
2/ Wind disturbances over the car, any wind would have been amplified over the Obstacle (forming un-even Up/Down etc winds at different heights above/ in front/ aside/ etc etc of the car).

By the way.
Well done !
Any flying day you can put you heli away without Gunk cleaning or major overhaul is a Good Flying day :)

Heli Jim
07-29-2007, 01:42 PM
WEll done!!!

Long flights and hovers are a great feeling.

You said something that made me uncomfortable, however, and that was seeing how long you can go with a lipo...this is dangerous, if you don't know it.

You should NEVER fly with them to a total discharge.....you can damage the battery and it could possible cause a fire. You should monitor the voltage and stop when the voltage gets down to about 3.2 or 3.3 volts PER CELL.

Sorry to sound preachy on you--well, it is Sunday, after all,--but if you don't know about LiPo's, you should check out the forum here for more info.

Now, go fly and have fun!!!

dotyj
07-29-2007, 06:52 PM
Not to worry, or maybe to worry. When the lipo voltage came down, I stopped flying. I'd read that bringing the voltage too low on a lipo pack will damage it, and that's the last thing I want to do.

I don't have any equipment for in flight monitoring of the battery pack. What I do is fly until there is an obvious drop in power. I can tell when the power is dropping off by how much throttle I need to maintain my hover, it becomes obvious when I need more throttle for liftoff.

I don't know if that's a good way of monitoring battery voltage during flight, but it's all I have for now.

After the flight I let the lipo pack cool completely before I put it on my charger.

I bought one of those Align chargers with the LEDs and multiple balance charge battery connectors. Perhaps not a great charger but it seems to work okey. I don't charge unattended batteries and find something to do in the room I'm charging in so I can keep an eye on things. I periodically touch the battery pack during charging to check for heat. So far my pakcs have remained cool to the touch during charging.

Heli Jim
07-29-2007, 08:00 PM
Good for you.

I would suggest that you look for a good volt meter so you can check to
see where your pack is when you finish flying.

Once you start doing that, you will know how long you can fly without draining too much out of the pack.

dotyj
07-29-2007, 09:42 PM
Good for you.

I would suggest that you look for a good volt meter so you can check to
see where your pack is when you finish flying.

Once you start doing that, you will know how long you can fly without draining too much out of the pack.

Good idea. I actually have a couple of them pesky DMMs. It would be nice to buy a small DMM though that will easily fit in my flight box.

HX3D014
07-30-2007, 02:04 AM
Good idea. I actually have a couple of them pesky DMMs. It would be nice to buy a small DMM though that will easily fit in my flight box.
That will be enough until you wish to do inflight monitoring.
You can get a good Idea of how hard you are pushing your battery by the charge it takes.

But, Most would start with a short flight time . chech the charge, then increase it from there..

I usualy go to 75% of Capacity. what % is everyone else going to?
IE my LiPo is a 1200mah, when I charge it(After a 9+ min Flight) It usualy only takes in 900ma - 1000ma.

Heli Jim
07-30-2007, 02:33 AM
My charger doesn't tell me how many ma I put in so I generally check
the voltage remaining and try to be at or about 3.4 Volts MINIMUM per cell.

I know I could go lower but I don't feel like pushing THIS envelope much

wlfk
09-23-2007, 06:39 AM
Well done!

My experience is that a few weeks back I suddenly reached a point where I stopped crashing often. It feels good, and my wallet agrees!

K

RacingTiger04
09-23-2007, 03:09 PM
congrats, sounds like you're not far away from starting some nose-in. It's a funny feeling when you first start hovering around with ease (and can make for overconfidence in my case where a mechanical issue was holding me back more than i relized!.. stupid sticky collective.. -.- ) I havent crashed in a couple weeks now until last night, and that was only because of a weak battery combined with stupidity.. short version i was playing with idle up and doing yo-yo's(it sure looked cool at the time! :P) with my heli, no damage though! except my pride