# Battery Charging Methods

Discussion in 'Instruments / Avionics / Electrical System' started by Johnny luvs Biplanes, Mar 29, 2004.

### Help Support HomeBuiltAirplanes Forum by donating:

1. Mar 29, 2004

### Johnny luvs Biplanes

#### Well-Known Member

Joined:
Mar 23, 2003
Messages:
283
2
Location:
Epsom Downs, Surrey, England
Hi all,
I want my projct to have a handprop system and no magneto.
Therefore it needs a source to charge a battery to run the distributor for sparks!
The options for this are:
1. Do nothing but charge the battery using shop power when hangered.
2. Fit an engine driven alternator setup, either motorcycle type or car type.
3. Make and fit a wind generator system (it's a period aeroplane)
4. Fit a solar charger into the top face of somewhere that sees sun.
I didn't really fancy a car type alternator or no charging system at all, a discreet motorcycle type is a possibilty but needs some work to mount onto the crank.
I do quite like the idea of solar power but this has drawbacks in panel size and charging output.
Finally the good old wind generator, this could well fit the bill but it's not my favourite (solar power is).
So the question for you all: what are the benefits/drawbacks of the wind generator and solar power and does anyone have some designs for either?
Cheers, John

2. Mar 29, 2004

### Dust

#### Well-Known Member

Joined:
Feb 9, 2004
Messages:
302
1
Location:
Troy, Michigan
was said
I want my projct to have a handprop system and no magneto.

don't you mean no alternator?? or is this thing a diesel

enjoy the build

dust

3. Mar 29, 2004

### Marilyn

#### Well-Known Member

Joined:
Mar 26, 2004
Messages:
63
0
Location:
Durham, NC
No mag? OK

I believe you mentioned it some time ago in another post, but what engine are you using?

4. Mar 30, 2004

### StRaNgEdAyS

#### Well-Known Member

Joined:
Oct 20, 2003
Messages:
816
3
Location:
Northern NSW Australia
I can see what you mean there Johnny.
Without a magneto to provide the ignition charge your battery will be the sole source of electrical energy to charge the coil. This can drain even a very large battery in a relatively short amount of time. (have you ever driven a car once the alternator has failed?)
Although solar technology has come a long way in the last 10 years or so, you may find that keeping up with the (electrical) current demand of running an engine, coupled with the electrical drain of your instuments and radios (if you are installing them) will be a little too high for a basic solar charging unit to cope with.
I too have been looking at this option for charging on my design, although apart from supplying the initial spark for ignition, I have no need for electrical input to the engine at all aside from monitoring. As such I can use a solar array mounted on top of the instument panel (I have a fair distance from the edge of the panel to the front of the canopy for aerodynamic reasons) to charge a NiCd or NiMh battery pack in the nose of the plane. But as I say, I will not have as high a demand for electrical energy as you.
If you can, try to get an idea of the kind of load you will have to deal with, run your engine, along with any other equipment you may need to simulate a full current load and record said current load with an ammeter. Then go shopping for a suitable solar array to cope with that load. You may get lucky. Several years ago British Petroleum LTD did some extensive research on solar power systems in conjunction with the solar powered vehicle races here in Australia, if you could chase up some of their data it may be helpful too.

5. Mar 31, 2004

### spark

#### Member

Joined:
Mar 13, 2004
Messages:
13
0
Obviously you would be limited to daytime flying and perhaps only very sunny daytime flying if you go with the solar power.
Seems to me that you would need one heck of a solar power panel to keep every thing alive. I personally would never rely on just the battery. If battery is all you got I would call that an emergency situation.
In my opinion, I would use some sort of alternator/generator or maybe even a combination solar and alternator. I'm sure weight and space are major factors. Good luck!

6. Mar 31, 2004

### StRaNgEdAyS

#### Well-Known Member

Joined:
Oct 20, 2003
Messages:
816
3
Location:
Northern NSW Australia
That won't be a problem for me, as my plane will be a VFC only craft, and my electrical load will be quite light. Don't know about Johnny's one though...

7. Mar 31, 2004

### spark

#### Member

Joined:
Mar 13, 2004
Messages:
13
0
I'm kinda surprised!
What kind of instrumentation will your craft have?

8. Mar 31, 2004

### StRaNgEdAyS

#### Well-Known Member

Joined:
Oct 20, 2003
Messages:
816
3
Location:
Northern NSW Australia
One thing I forgot to include in my earlier post re-engine electrics, I will be running an electric fuel pump to power the injection.
OK ,what it HAS to have
• Altimeter (ft)
• ASI (kts)
• Mag Compass
• Landing gear position
What I WANT in there
• Artificial Horizon
• Turn/Balance
• VSI (fpm)
• EGT
• Portable NAV/COMM (own power)
• Portable GPS (own power)
Wishlist (Will require extra power and a lot more  than I can spend right now :wail
• 2MFD's
• Bitchin' Betty
• Autopilot
I'm pretty sure that once I work out the Current demand of the instuments, I'll be able to find a solar array to cope with it.
Also keeping in mind, I'll not be up there for much more than an hour anyway (quite probably less) I can plug the plane in when I land. :gig:

9. Mar 31, 2004

### Johnny luvs Biplanes

#### Well-Known Member

Joined:
Mar 23, 2003
Messages:
283
2
Location:
Epsom Downs, Surrey, England
Hi all, to clarify: I don't want or need a magneto or alternator really. I'm gonna build me a Corvair with WW,s dual ignition setup, this draws 2.5amps and will be the only thing to power, no radio no nothing. Dead basic biplane so no long/large solar panel really I guess looking at the posts. The cowling won't allow an alternator probably though a small m/cycle one could possibly be direct mounted to the crank? A wind generator would be nice and fit my 1926 style aeroplane, don't make em anymore though! A small solar back up might suit possibly, has anyone tried this in gliders?
Cheers,
John

10. Apr 1, 2004

### Marilyn

#### Well-Known Member

Joined:
Mar 26, 2004
Messages:
63
0
Location:
Durham, NC
Ah!

Well, that's a different story then.
Why aren't you using the standard Corvair setup with the front mounted alternator and starter? I don't think it changes the engine dimensions. If it's about the weight, you ought not be running a Corvair anyway. A Rotax 912 puts out 100 hp and weighs 50 pounds less than a Corvair. A redrive equiped VW can put out 100 HP at around 180 pounds.

But anyway, if you are just looking for a way to recharge your battery in flight, you have several options.
I saw several wind generators for sale at Sun n' Fun and Oshkosh last year. Not in the swap meet tent, but there were several vendors of...
Parts. Misc. parts. Antique, out of production, salavge... You know, like they clean out a hanger that hasn't been in 25 years or so and sell what they find. So what I'm saying is that you can find one and they are pretty simple machines, so they aren't hard to repair if you can find the parts.
There is also one or more companies manufacturing wind generators today. they are small, lightweight and I thought kinda expensive, but I'm pretty cheap when I'm dreaming. I have seen an ad in Sport Aviation or Kitplanes and I actually saw a product at Sun N Fun last year.

Last edited: Apr 1, 2004
11. Apr 1, 2004

### spark

#### Member

Joined:
Mar 13, 2004
Messages:
13
0
StRaNgEdAyS,
You wont be needing a transponder where you fly?
In the USA free airspace becoming kinda scarce unless you only fly super low.

12. Apr 1, 2004

### Johnny luvs Biplanes

#### Well-Known Member

Joined:
Mar 23, 2003
Messages:
283
2
Location:
Epsom Downs, Surrey, England
Hi Marilyn, the "standard" front mount alternator is big and bulky, weight is ok as is but don't want a front mount. It gets in the way. A 912 is TOTALLY unsuitable for a 1926 style aeroplane with part of the engine protruding. Less weight is not a benefit as it will totally upset the balance of the design. A VW redrive appeals as much as AIDS The Corvair is ideal and very under rated.
Cheers,
John

13. Apr 1, 2004

### Marilyn

#### Well-Known Member

Joined:
Mar 26, 2004
Messages:
63
0
Location:
Durham, NC
Well then

VW redrive appealing as AIDS? out: Don't peek under my cowling OK?

Well, I was just going by the picture on William Wynne's website and it didn't look to me like the alternator and starter stuck up very much above the spinner.
1926 with engine hanging out? What the heck are you building Johnny? And if you is such a stickler for the looks, what are you doing hanging an auto conversion out where people can see it anyway? You should toss that plan out and get one of those Rotec radial engines. Nothing looks better on an old timey biplane design than a radial.

14. Apr 2, 2004

### StRaNgEdAyS

#### Well-Known Member

Joined:
Oct 20, 2003
Messages:
816
3
Location:
Northern NSW Australia
That's the beauty of living in Australia. It's such a BIG place. (We even surprise TEXANS! :gig
Once you get out of the cities, almost everything is free space, but you are limited to 5000ft ceiling, which in certain circumstances, if fitted with a radio set, extends to 10000ft, which unless you have O2 is probably a good thing.:tired: Even so, with the right paperwork, you can fly an ultralight (light sport/recreational :gig aircraft in controlled airspace over here if you are radio equipped and hold a GA license. :ermm:
In such cases, a transponder is only required if the airport/aerodrome you are proposing to land at requires it.
Not even an ALT&ASI??? Wow :suprised: They and a mag compass are mandatory for homebuilts over here.

Last edited: Apr 2, 2004
15. Apr 2, 2004

### Johnny luvs Biplanes

#### Well-Known Member

Joined:
Mar 23, 2003
Messages:
283
2
Location:
Epsom Downs, Surrey, England
Hi Marilyn,
I'm going to build a Flitzer Falke Z3 biplane, see attached.
A radial would look nice but this I prefer.
Cheers, John

#### Attached Files:

• ###### flitzer falke z3.jpg
File size:
33.9 KB
Views:
977
16. Apr 3, 2004

### Marilyn

#### Well-Known Member

Joined:
Mar 26, 2004
Messages:
63
0
Location:
Durham, NC
Johnny

Dude! That is one cool looking old timey airplane. How will it handle? Have you ever flown without a forward view? How do you get lined up to put it down? they didn't have runways back in that age.

Anyway - ok then my last word on the actual topic is - With that big ass rounded cowling it looks to me like there is more than ample room for the "stock" alternator to be hidden away, and since I can't fathom why anyone would want to hand prop an airplane, the starter too, becuase unless you are one of those "authentic is everything" guys that is going to waste years of flying and building time becuase they can't get the exact make and model for every instrument, specific color paint, a Le Rhone engine that was built no later than a specific date, and stuff like that.
I've met guys like that, and I completely respect their desire for a perfect reproduction.
However, if you are going to put brakes and a tailwheel on your plane so you can fly it off a concrete runway, and you are going to put new instruments in that panel to monitor the Corvair engine that was designed by a guy born after your airplane no longer graced the sky - then the best you are aiming for is a cosmetic reporduction. One that looks and flys like the original. I think these are great too, one of my two projects is a nose to tail rebuild of a scaled down Pietenpol. The original builder had decided to inovate, building a pushrod actuated elevator. I'm going to tear that out and go back to the wire driven one because it will look better - more realistic - and oh by the way it won't call for heay reinforcments of the flight controls to accomodate it.

So my point, and I do have one - is: If you are modernzing the aircraft to make it usable in tody's flight environment (rather than building a perfect reprodution to be put in a museum or flown at airshows) - and you are Johnny - then just go ahead and modernize it. Particularly in your case Johnny, building a type that hasn't been around for 75 years... No one will have any idea what changes you made to the original, so long as it looks right on a "walk around the outside to take pictures for your local EAA Chapter Newsletter" kind of inspection, so you might as well build a USEABLE antique design biplane.

And that's all I got to say about that.

Last edited: Apr 3, 2004
17. Apr 3, 2004

### Johnny luvs Biplanes

#### Well-Known Member

Joined:
Mar 23, 2003
Messages:
283
2
Location:
Epsom Downs, Surrey, England
Hi Marilyn, the Falke is a new design from a modified Z1 Flitzer (that's just designed to be like a 1926 aeroplane of German origin)! The Z1 is fractionally smaller with a VW style motor and flys EXTREMLY well, the Falke will be even better. Hands off stable without any trimming system and 360 degree turns in 7 seconds maximum. It has NO brakes or tailwheel so grass only There probably is room for a alternator up front but the cowling is actually quite tight even on the VW variant. What i'm trying to avoid is a belt driven alternaor really, direct mount would be acceptable. The forward view would be hampered slightly if fake Spandau guns were fitted. However otherwise it's very good in flight as it's small and only needs a slipping turn on final to land. Period items won't really be fitted as I don't think it will matter, instruments will be minimal and suitable.
Cheers, John

18. Apr 4, 2004

### Marilyn

#### Well-Known Member

Joined:
Mar 26, 2004
Messages:
63
0
Location:
Durham, NC
Well,

Then this brings us back around to your wind generator. I've looked through this months magizines, and I don't see it in there.
Are you going to Sun n Fun?

19. Apr 5, 2004

### Johnny luvs Biplanes

#### Well-Known Member

Joined:
Mar 23, 2003
Messages:
283
2
Location:
Epsom Downs, Surrey, England
Hi Marilyn, no i'm not going to S&F as it's a major trip from the UK and i'm also trying to save money for my project. One day i'll get to do that and OSH but until then it's dream on! We do have the PFA rally here which is 3 days and 2000 aircraft so it's pretty good.
Cheers,
John

20. Apr 5, 2004

Joined:
Oct 20, 2003
Messages:
816