hyper701

I've got a lanyu hobby 1400mm corsair with brushless out runner setup, running 2200mah 3cell lipos and I'm only getting about 1/2 min run times, it's not worth going out for short flights like that. I'm not looking for more power just longer flights pls help what batterys do i need?

guver

My Feedback: (325)

I'm not familiar with the plane , but I would sooner think that there's something wrong with your batt/charger set-up. Is that the recommended batt for the plane?

I'd almost bet money on a faulty charger and/or pack balance. If it really is the recommended pack then perhaps you can double the capacity.

exeter_acres

My Feedback: (2)

something is clearly not right...

link to the plane would help....

using a volt meter.. what is the voltage of your battery pack when you take it off of the charger?

hyper701

Sorry I don't have a volt meter, I have been using the standard charger that came with the plane, and that's the battery that came with it as well The link http://www.lanyuhobby.com/viewProduct_en.asp?flowNo=350

guver

My Feedback: (325)

You may only have to invest in a charger. HobbyKing has them for under $20 usd and this will be a good first step in diagnosing the batt as well. Can you borrow a voltmeter? All cells should start out at 4.2 volts when fully charged. If not then of course the flight time will be less than normal.

hyper701

I am running a apc 12x8 prop on this plane. Could the motor be chewing thru the battery's because of that? Sorry I'm kinda new to this electric stuff

guver

My Feedback: (325)

1/2 minute is 120 C and a pack would be very hot if most of the capacity were being used up in 1/2 minute. The only way to be sure is to start out with a volt check. Beyond that a per cell check and then an after volt check. I'm guessing that the pack isn't being fully charged.

hyper701

ok so how do i do a per cell check? and also how long filght should i get out of these batterys? oh yeah and what does it mean to double the capacity of the battery?

guver

My Feedback: (325)

The balance tap (small white or black plug) has 4 wires and connections. To check each cell probe adjacent pins with a dvm to read each cell's voltage. They should all read the same and be about 4.2 when charged. Be very careful not to touch them together , it is best to use a connector of some sort that will prevent shorting them. sorry I can't know the flight time , but to double the capacity of the pack one needs to use 2 packs or buy a pack that is twice the capacity.

http://www.scriptasylum.com/rc_speed/lipo.html

hyper701

thankyou you have been verry helpfull, i will go and buy a volt meter today.

exeter_acres

My Feedback: (2)

doesn't have to be super expensive.. the Radio shack ones are fine for most of us....

but it is a valuable tool

hyper701

unfortuanatly i could not get my hands on a volt meter today, but i did get a chance to charge the batterys with a propper lipo balance charger and did some testing on the flight times of my fully charged batterys.
both batterys took no longer than 1hr to charge
the 3 cell 1800mAh battery lasted 3min 10sec
and the 3 cell 2200mAh battery lasted 4min 55 sec
as far as these batterys go is that what i should expect?

Quorneng

When you say flight times are these actual flying durations or full power ground runs?
The Lanyu Hobby Corsair is big but light so full power should not be required all the time.

The original uses a 12x6 three blade prop. Is this what you are using?
On this sort of electric plane the correct prop can make quite a difference to both the performance and duration.
There are several videos on You Tube and they seem to be able to get 4 or 5 minutes on the stock 1800mAh battery.

The fact that the Corsair is quite big suggests it would handle a bigger battery but it might need a more powerful motor as well to carry say a battery of twice the capacity & weight.
   

hyper701

sorry, yeah they were full power ground runs, the plane is all stock except its got a apc 12x8 two blade prop. im kinda new to all this and that prop was suggested by a friend, can you reccomend a better one ??

hyper701

sorry, yeah they were full power ground runs, the plane is all stock except its got a apc 12x8 two blade prop. im kinda new to all this and that prop was suggested by a friend, can you reccomend a better one ??

Dr Kiwi

Long full power ground runs are NOT recommended... motors should be limited to 15-20 seconds of WOT unless you have in-flight cooling... if you are using up a 2200mAh pack in 4min 55secs... you are drawing ~29A/>300W.. is your motor rated to cope with this.. is it getting too hot during these WOT ground runs.

The only way to get longer flight times is to A. decrease prop size and amp draw, or B. increase pack capacity. or C. use WOT sparingly.

DustBen

My Feedback: (3)

I have to wonder about the health of his LiPo's after some of the abuse they took.

I'd buy at least one, if not two new 2200 mAh 30C Lipo's and see how they perform.

I also wish we knew what motor he was running, what thrust he's making, and if he can step the prop and pitch down which would go a long way to further extending his run times.