endurance

| How long would a 1500mAH battery last in the avarage two channel setup | i.e receiver and two servo's?

It's hard to come up with any `average two channel setup', as it depends on how you fly, the plane itself and the servos and how they're installed, but if it's a nice gentle thermal glider, probably for several hours -- perhaps seven?

That's just a guess though. Really, what you'll need to do is cycle your battery and determine it's capacity, charge it again, then go fly for a known number of hours, then drain your battery when you're done and find out how much capacity is left, and do some simple math to estimate how long you could have stayed up -- then subtract a generous safety buffer.

If your glider has any ballast or weight added to make it balance, you could replace it with a bigger or another battery pack ... if you're going to send up weight, it might as well be useful weight!

The message from "Doug McLaren" contains these words:

Hi Doug, as long as I can get two or three hours out of it I will be happy, the a/c is a 80'' span thermal which I did intend to fit a motor to but as I havnt flown powered models for a very long time and am only just getting back into flying models at all I thought I would start at the bottom so to speak and work up so the glider I am finishing has just the receiver and two servos We used to use dethermalisers but now its all micro circuits and electronics so should be much more enjoyable as I can control what it happening, the glider has been built to take a motor fit at a later date so may use a larger battery anyway to get used to its size and weight, have seen some 6 cell AA Ni-MH rated at 2400 mAH which would fit just nicely into the cockpit space and leave space for moving fore and aft for balance so may go for one of those,

regards, Terry

You should easily get 2 -3 hours flyong out of the 1500 mA receiver battery. As long as you don't have any really stiff or binding linkages.

I fly mainly slope and thermal gliders, although I am not adverse to putting on a power pod when the wind doesn't blow on the slopes.

My 100 inch glider will fly very nicely in thermals with just a tiny amount of control input... more of a slight nudge really. I reckon that the transmitter battery will be starting to get low before I need worry about the receiver batteries in my different models. Most of my gliders are rudder, elevator with some aileron controlled ones as well.

Welcome back.... nothing so nice as pootling about in thermals on a nice day. The weather forecasters are predicting a "blisteringly" hot summer for this year. I just hope they are right !!! I love hot still weather, a diesel with an exhaust extension quietly chuntering away... climb way up until the fuel runs out and then the long slow glide and search for thermals.... hell I am packing the sarnies ready !

Reg

My personal testing has shown that a 4channel trainer consumes about

40-60mAh per flight. The upper end being when you tend to throw it around rather than use it as a 'trainer'.

So, using the same receiver and only two servos you'd be around half that. Of course, it sounds like you're soaring/gliding which means you may see lower servo loads and thus use even less power.

A friend of mine once claimed a 3 hour slope soaring flight, he was using a

2 channel setupo with a 600mAh pack. Note that most TX batteries will rarely exceed 3hours of use.

Regards

| as long as I can get two or three hours out of it I will | be happy

Then you'll probably be happy. Two channel gliders don't use much power.

| so may use a larger battery anyway to get used to its size and weight, | have seen some 6 cell AA Ni-MH rated at 2400 mAH which would fit just | nicely into the cockpit space and leave space for moving fore and aft | for balance so may go for one of those

RX/servo packs should be 4 or 5 cells -- six cells will probably fry something unless you use a regulator. And contrary to common sense, a five cell pack will probably last slightly *less* long than a four cell pack.

Either way, I'll bet a 4 cell AA 2400 mAh pack would last over 10 hours in your plane unless you've screwed things up and your servos are binding. At some point it just become silly to get more duration

-- unless you're going for your LSF V 8 hour slope task, that is!

| A friend of mine once claimed a 3 hour slope soaring flight, he was using a | 2 channel setupo with a 600mAh pack.

Sounds perfectly reasonable.

(And on a good slope with good conditions, three hour flights are not uncommon. It's one of the things that makes slope flying so much fun

-- fly all day, never worry about landing for more fuel, new batteries or even not being able to find thermals.)

| Note that most TX batteries will rarely exceed 3hours of use.

Stock batteries, maybe.

My Futaba 9C (a.k.a. power hungry computer radio) lasts 6 hours on it's 1800 mAh NiMH pack. I'll bet a non-computer radio could do over

12 hours on a 2400 mAh pack.

To be fair, the stock 600 mAh pack only kept it going for a little over two hours.

"Doug McLaren" wrote in news: snipped-for-privacy@frenzied.us:

Concur, and I have data! Once upon a time, I charged up all my Tx's, put them on a table, and turned them all on to see how long they'd run. I'd shut off a Tx when I got a low battery warning, or the meter got close to red, or whatever. Among the collection were 3 Hitec Neons. For those unfamiliar, the Neon is a very simple, cheap 3 channel radio that's suited for 2-channel gliders or simple electrics.

The Neon with a 600 mah battery lasted 4:45, suggesting that with a 2400 mah battery, it would gone for around 18 hours.

After 5 hours (5:12, according to my notes), I stopped the test. The other 2 Neons had 1200 mah batteries and they were still in the green; based on the first one, I would have had to wait another 4.5 hours and I just wasn't that patient.

Very consistent with my results. I have 2 Optics with stock batteries; one lasted 2:44 and the other hung on another 6 minutes to 2:50. The Optic is a computer radio, but it's not as tricked-out as your Futaba.

- Mark Miller

The message from tux snipped-for-privacy@nowhere.at-all.net contains these words:

Hi Reg, I hope they are right too seeing as the temp outside right now is about 29f!! about 3 minutes walk from my house is what was a small quarry back in the 1800's and has now been landscaped with a pathway through the middle but there is still one nice big hill on one side and some quite promising slopes and the beauty is if I crash it the workshop is only a few minutes walk away!,

regards, Terry

The message from "Doug McLaren" contains these words:

Hi Doug, Much easier to just take an extra pack or two fully charged than have an airframe lugging a big lump of unneccessary battery around, I am not into attempting any endurance records as I tend to fall asleep every three hours or so after a cup of tea and especially when the sun is shining,

regards, Terry.........(snooze)

The message from "Doug McLaren" contains these words:

Its nice to know the electronics can keep going longer than I can Doug......;-),

regards, Terry

Hi Terry,

That sounds very similar to something not far from me. You are not on a certain South Cumbria peninsular are you ? If you are then I can suggest some very good places nearby. Probably coincidence and you are at the other end of the country >:-)

Reg

The message from tux snipped-for-privacy@nowhere.at-all.net contains these words:

No Reg, down south in Telford on the edge of the Ironbridge Gorge, we had a lot of industrial developement in this area with Coalbrookdale and the Darby family so there are a lot of old coal mines and various old and now disused pits and so on most of which have been reclaimed and landscaped now and this plus the natural topography around here makes for some nice little areas of slopes and valleys. Just a few miles to the south west we have the Wenlock Edge and a bit further on through Church Stretton is the Long Mynd and Stiperstones which is all hills and deep valleys and there is a gliding club based up on the Mynd, a perfect quiet place for a summers sunny afternoon up high on the lovely green hills with a picnic and some beer just watching the gliders playing in the sky,

regards, Terry

Hi Terry, Definitely not the same place, just seemed so similar in the description. You obviously have some GOOD sites near you so I don't have to go sharing my local ones.

I have been building up a small fleet of gliders for different conditions. Some are very good in a strong wind, others are for when the conditions on the slopes are light and there is a selection of diesel and glow powerpods for use in calm weather. I fly off coastal hills, the winds are smooth and there is usually a goodly supply of thermals coming up from the sand in the estuaries.

A nice 20 mimute drive sees me on the slopes and I can usually spend the day up there without seeing anyone..... brilliant >:-)

I have just ordered a plan for the Bird of Time from the States. The £ is strong against the $ and now was a good time to get it. I have fancied building one for a while now and it is going to be next winters build job, although I will spend time during the warmer months cutting all the wing ribs and making up a "kit" of parts ready for when I start building. For a mere £10, which includes airmail, I will have hours of fun !

Regards, Reg

The message from tux snipped-for-privacy@nowhere.at-all.net contains these words:

Hi Reg,

Saw plans for that one on eBay a few weeks ago as I recall, been looking for plans for a Minimoa for a while as it is the one glider that has always held my attention but havnt seen any plans for it on eBay yet,

regards, Terry