Upgrade Batts for a Skytech Gaui Hurricane M1

policetac · Charging Joined: 07 Dec 2014 Posts: 2

Hello everyone!

Walking through my local second hand antique mall the other day, I turned the corner and saw a huge box with a giant RC helicopter in it. Man it was cool! It was bright Red, brand new, (almost) and looked just like the one's I've been playing with in my living room over the last couple of years. Except this one was HUGE! "Oh my ...! I want it." I kinda said to myself knowing that as soon as I looked at the price all I was going to do was get mad.

But I had to look anyway. "Whaaa?" I said to myself. "No way!" "Brenda!" (my wife) I almost hollered across the place, "Come check this out!" "It's so cool!" "Man I"......You get the idea! lol

Anyway....Since my birthday was in a couple weeks, I made her a deal. I told her that if I could get it she wouldn't have to buy me anything this year. Heck. I'd even pay for it myself I told her. Well, of course she said she didn't care. (I've got a really cool 'ol lady

Okay. So I got it home and sure enough, it had enough of a charge in it to let me know it did in fact work, but that I was going to have to wait a little bit longer as it was going to need a good charge before I could really get it up in the air. So, I hooked it up and long story short, (too late) the charger didn't work.

No biggie there I figured. I'd just make one myself. So I did. It works somewhat, but since we're dealing with Li-ion batteries here I figured the best thing to do was go ahead and see if I could find some replacements along with a new charger.

I had a little time to think about it though and came up with some ideas. I wondered to myself, "If I wanted to upgrade a Camero, I'd buy a new motor. But if I wanted to upgrade a helicopter, I'd just have to upgrade the batteries.

1. Is that correct? Yes, I know that motor upgrades are possible with these devices, but since I'm going to be buying batteries anyway, would a battery upgrade allow me better performance as well as longer flying time?

I looked up everything I could find on the helicopter and came up with this:

Skytech M1 Hurricane Metal 3CH RC Helicopter

Length: 31 Inches
Wingspan: 21 Inches
Height: 10.5 Inches

I think that it is currently using these batteries:

7.4V 1500MAH RC spare parts lipo battery for Double Horse 9053 RC Helicopter

I'll go ahead and hang out for a bit in case somebody responds to this right away.

Thank you to all in advance.

policetac

Burgess · Extreme 3D Joined: 27 Mar 2012 Posts: 1103 Location: Wales

Hello policetac and welcome to the forum.

The short answer to your question is, not quite. With any helicopter the considerations are different to those of automobiles.

Two aspects, first centre of gravity (CG), second disk loading.
So there is an optimum size/weight of battery, basically the one that the manufacturers supply.

The problem with those large 3 channel co-axil helicopters is they are supplied with radio equipment intended for use with small co-axil toy grade helicopters, so usually only good for short range indoor use. Fly one of those large co-axils outdoors, the wind can soon take it out of range of the transmitter...it does happen. You would really need to do a ground level range check to know the limits of transmission prior to flying it.

Why not consider purchasing a hobby grade 4-channel fixed pitch heli and 2.4ghz radio set. See what they have down your local RC hobby shop, and visit an RC heli club they may even do buddy-box flying.

Burgess

policetac · Charging Joined: 07 Dec 2014 Posts: 2

..."since we're dealing with Li-ion batteries here I figured the best thing to do was go ahead and see if I could find some replacements along with a new charger. "

..."But if I wanted to upgrade a helicopter, I'd just have to upgrade the batteries.

1. Is that correct?"

..."would a battery upgrade allow me better performance as well as longer flying time?"

------------------------------------------------------------------------------------

..."Why not consider purchasing a hobby grade 4-channel fixed pitch heli and 2.4ghz radio set."

???

Yea...That's not really an option at this point. But thanks anyway...

The info about the center of gravity helps though. But looking at batteries earlier today I did notice that larger mAh capacity batteries are about twice as long as the OEM ones I'm trying to replace. I have been able to find same size replacements,l but not in any higher output range.

As to the other part of your advice, what is "disk loading?"

Thanks,

policetac

Burgess · Extreme 3D Joined: 27 Mar 2012 Posts: 1103 Location: Wales

Disk loading = weight to total main rotor disk area.

A typical 450-sized electric helicopter may weigh 800 grams (0.8Kg) and have a rotor diameter of 70cm (0.7m), giving a disk loading of:
0.8/(pi*(0.7/2)^2) = 2.1Kg per square meter. [See RC helicopterWiki]

performance has more to do with rotor blades than battery discharge rates.

OEM Li-ion 7.4v 1500mAh
Size: 68MM(L)*39MM(W)*20MM(H)
Weight: approx. 95g

Here's a LiPO 2S1P battery that you could consider using in place of the OEM Li-ion battery. You will need a discharge indicator that plugs into the balance lead.

Zippy Compact LiPO
Capacity: 1800mAh
Voltage: 2S1P / 2 Cell / 7.4V
Discharge: 25C Constant / 35C Burst
Weight: 93g (including wire, plug & case)
Dimensions: 106x12x34mm
Balance Plug: JST-XH
Discharge Plug: XT60
Price $8.30 each from hobbyking.com

LiPOs are classified by ‘C' ratings. [the C value = x times the total capacity of the battery].
i) maximum charge rate;
ii) continuous discharge rate;
iii) maximum burst discharge rate.
It's important to know how to handle LiPO batteries. Must not be over discharged or over charged, here it's the voltage per cell that's important. Therefore you will need a good quality balance charger, such-as an authentic iMAX B6 charge.

****************Edit*********************
Safety Note, best practice remove the LiPO from the helicopter each time to charge it and when not in use the voltage needs to be at storage voltage 3.8v per cell.
*****************************************

Burgess