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Slick
01-11-2007, 01:04 PM
I am not sure if this is a silly question or not.

I have the optional suggested EFlite brushless set up. After that set up the tail would not hold so I went through various tail mods and by far the best one is the GWS direct drive. It is cheap and very small modifications to get it to work with the BCPP.

The problem I am having now is when I do a little fast forward flight and start to turn around I really start to loose altitude. What I discovered is the when I jam the rudder the heli will dip. I was not really sure what to do about this so here is my question.

The Eflite battery is an 800mA 3 cell 11.1 V LiPo with 10C and 12.5C burst.

Do you think that this battery does not have enough burst C to handle the direct drive tail?

If so, I see Carlos is using the TP 910 (3cell, 11.1V 16C with 24C short burst) and TP 1320 (3cell, 11.1V 13C with 20C short burst).

Does the extra burst of the TP 910 and the TP 1320 help with such issues of the tail potentially trying to get more power?

I should know more about this then I do.

Thanks for any help,

-Craig

carlo_the_wonder_frog
01-11-2007, 08:20 PM
Flying with good batteries makes a big difference, The stock battery peters out quickly, still flyable but no grunt anymore. A good LiPo that can discharge at a higher rate will give you much more usable power throughout the whole flying session. Basically the stock battery is capable of a constant 8 amps, while a TP 16c 1320 can put out a constant 20 amps, twice the available power than the stock LiPo. Burst C is the maximum power output of that battery, 10 seconds or less is a burst, anymore and you are discharging too hard. My brushless setup pulls between 8 and 13 amps depending on how aggressive I am.


You will definitely see an improvement with a high discharge battery over the stock LiPo.

Slick
01-11-2007, 10:37 PM
Flying with good batteries makes a big difference, The stock battery peters out quickly, still flyable but no grunt anymore. A good LiPo that can discharge at a higher rate will give you much more usable power throughout the whole flying session. Basically the stock battery is capable of a constant 8 amps, while a TP 16c 1320 can put out a constant 20 amps, twice the available power than the stock LiPo. Burst C is the maximum power output of that battery, 10 seconds or less is a burst, anymore and you are discharging too hard. My brushless setup pulls between 8 and 13 amps depending on how aggressive I am.


You will definitely see an improvement with a high discharge battery over the stock LiPo.

Wow, if you are putting out between 8 and 13 amps that could really be my problem. I was planning on stopping at my local hobby store this evening and pick up a TP batt if they have them, but I was wanted to see a response to this post first. The more I think of it, I think this is my problem.

Thanks for your inpu Carlo :)

-Craig

Skiddz
01-11-2007, 11:50 PM
You need to add power in a turn. In forward flight, the lift vector is pointed straight up and slightly forward. When you turn, you "tilt" the lift vector over so there's not as much lift acting directly against gravity. In addition, since you need to add roll and a bit of aft cyclic to pitch the heli through the turn, you're now demanding more power since you're adding collective pitch AND cyclic pitch which increases rotor drag.

Add a touch of power through the turn and remove it as you roll out and you'll be able to fly level through all but the tightest turns. You may need to add some right TR as you add power 'cuz of the increase in torque.. Just fly the tail through the turn and you'll be good.

Slick
01-12-2007, 09:01 PM
You need to add power in a turn. In forward flight, the lift vector is pointed straight up and slightly forward. When you turn, you "tilt" the lift vector over so there's not as much lift acting directly against gravity. In addition, since you need to add roll and a bit of aft cyclic to pitch the heli through the turn, you're now demanding more power since you're adding collective pitch AND cyclic pitch which increases rotor drag.

Add a touch of power through the turn and remove it as you roll out and you'll be able to fly level through all but the tightest turns. You may need to add some right TR as you add power 'cuz of the increase in torque.. Just fly the tail through the turn and you'll be good.

Lol, this is also what the local heli guru said at the hobby store. He took a look at my Tx (the DX7) and explained the program I could do. He set them up a little so I can't wait to get my bird back together and play with it again.

Thanks for your input Skiddz, I appreciate it! :)

I did get the 1320 batt and ordered the other batt as well. Since I have a TP charger I wanted to upgrade the bats for a while now so all is good.

Thanks everyone :)

-Craig