dynoflux

I have had questions about electric conversion; needed to pull the P-38 apart to upgrade speed controller software so decided to take some photos that should answer many questions. I have flown this plane and it flies well at 17.5 pounds.

nemesis4u

My Feedback: (77)

that is one cool set-up you have there... Nice installation...looks so clean... Literally...
How much did that e-set-up cost ? Imean the electric motors, speed controllers, batteries etc.... is it costly?? I wonder if it is about the same as nitro powered 4 strokes? hmm would make a 4 engine bomber a lot easier to manage if it were electric..
Can you provide us with some sort of breakdown on prices that it took to do what you did... Again... very nice and impressive!!!
way to go RAID HOT MAMA!!!!!!!

dynoflux

Thank you for the kind comments. The cost is compairable to top end 4-strokes. As far as I am concerned for more than one power plant electric is the only way to go. Power to weight is no longer a issue with electric as most planes I have converted weighed less than same model with nitro setup. I would consider fule/gas only for planes such as Cessna 337.

spindoctor

Looks like a very clean set-up, I'd love to see some in-flight video. How long does it take to charge the batteries, what charger and what kind of flight time?

Thanks,

nemesis4u

My Feedback: (77)

and what is the cost you paid for the set-up... Can you breakdown what was needed and $pent?? If not it is fine.. but I have never known anyone close to my home who has done this..

dynoflux

Duration depends on the throttle setting but as this is a airplane that I would not get aggressive with (thats for the Funtana); the real crowd pleaser is the low slow pass in front of the crowd. I have not or will not run the batteries down to low voltage cutoff as I am making sure they have a long happy life. From the power I had to put back into the batteries after earlier flights it looks like 15 minutes would be very conservative. Conservative is where I want to be with $500 worth of batteries. I use two chargers one ICE and one Astroflight; the ICE charges Lipos, NMHd, and Nicads. The Astroflight only does Lipos. Full Charge takes one hour; however, since I try to never need full charge my charging time is less (Lipos do not have the partial charging problems of Nicads on nmhd.

As for the cost that is a hard question because I use the same batteries in 4 airplanes. but I can list the prices paid for electric flight components:

2 Motors $240.00
2 Speed control $240.00
2 batteries $500.00
wire and connectors $25.00

Other than subtracting the cost of two servos not needed for electric flight other costs are equal to gas/nitro. Furthermore batteries in my case could be divided by the number of planes I fly with them. If we consider the expected battery life and the price of glow fuel over the life of the batteries it is just about a toss. If batteries ar abused it can shorten their life considerably; of course you could also be in the habit of tipping over your fuel container with the lid off. With everything considered initial outlay for electric will be higher but in the long run the difference is nominal.

dynoflux

I do have a short shakey video of the maiden flight but can't figure out hou to attach it.

dynoflux

Do Not use Castle Creations 60 amp speed controller with AXI-4120/18 and 6s Lippo as it will not handle the load. The right side controller burnt up on takeoff; Bad News; but only minor damage. I plan on using HV-85 when available.

topher39

My Feedback: (3)

Hello, I just ordered my P-38 and was going with the Axi 4130's - tell me with your setup using 4120's just how much power do you have, average throttle setting for sustained flight and how well does it climb? What altitude are you out and how many amps do you draw. I fly a hanger 9 P-51 and use the 4130/16 and thought it would be great for the P-38 - giving me some extra power and reducing the amp load when cruising. I would love you hear your feedback flying this plane as electric. Chris

dynoflux

The AXI-4120 supplies plenty of extra power with 6 lipo cells at 2600 watts at full throttle. The P-38 flies well at just above half throttle. During repair I changed my setup to a pair of AXI 4130/16 controlled by Castle Creations HV-85 Controllers and powered by 8 lipo cells; proped to the same 2600 watts. The reason I changed was to reduce current and the 4130s are better able to handle the 2600 watts. Batteries used are two 8000ma thunder power 4 cell pro-lite. This lowered current draw from 110 amps to 86 amps for both motors resulting in less voltage drop through wires and connectors. The plane now weighs just under 20 lbs. but feels no different in flight.

topher39

My Feedback: (3)

What prop are you using with the 4130s now. Why did you not stay with 6 lipos and a larger prop, instead of going with 8 lipos for the new setup?

What altitude do you fly?

What kind of vertical performance does this setup give you under full power?

You keep all your batteries in the center podm through a nose cone? - was it tricky to balance under this setup, did you have to add weight anywhere?

What is your opinion on the stock landing gear? Our club flys off of a packed Clay/dirt runway.

My Axi motors and my P-38 come this Friday - still shopping controllers. Looking forward to the project. Does the plane really fly as easy as they say in your opinion?

bruff

My Feedback: (18)

Getting my KMP P-38 this week. I'm going with the new Hacker A50 outrunner motors. Let you know on final setup.
Bob

dynoflux

Used 2 8000ma 4 cell lipo cells in series and 15/8 2 bladed props.

flyboy0

hey Dynoflux, you said you would only consider using gas/nitro in the cessna 337, why is that? I have a 337 and just about got my glow engines decided on.
I'm an electrician by trade and I was thinking about electrics, but I have no knowledge these types of electrics. any info would be great...thanks

dynoflux

The 337 has the thrust line of both motors on center of aircraft; reducing or totally eliminating the one engine failure issue.

red_z06

My Feedback: (11)

flyboy:

I have saito 100 twin powered 337. It needs 1lb of weight inside the firewall to balance. If I build another, I would go electric and I believe it would come out lighter on wet weight. However, you just can't beat the 4 cylinders singing as it goes by. I'll see if I can post the video here.


http://www.bsc-engineering-usa.com/B...ito100Twin.wmv



dyno:

I was looking everywhere for fai 3.5" spinner as it closely resemble p-38 spinner but no luck. Dave Brown has 3 3/8 FAI. I think it might look better than using standard spinner. Mine will be AXI 4130/16 powered. If I go for scale, I would use 6cell with 14x12e and for speed I would use 9cell with 12x10e. I had the latter setup in GP Little Toni doing 108mph. It would be a wild thing to see p-38 electric doing 100+

red_z06

My Feedback: (11)

Are you using Esprit Models 3 1/8 electric spinner?

dynoflux

I am using the Greatplanes 3 1/8 inch spinners with the aluminum back plate; these are great as they have holes machined in the back plate which allows additional cooling to the motor.

bruff

My Feedback: (18)

flyboy0
See http://www.muddyoval.com/tempftp/Bob_Ruff-Skymaster.wmv for my 1st flight of my KMP Cessna 337 electric. Waiting for motors for my P-38.
Bob

red_z06

My Feedback: (11)

I guess 3 3/8 fai spinner will not look so bad as 3 1/8 doesn't look so bad.

vertol

My Feedback: (18)

Hi guys,
I used custom tru truns so I could use counter rotaiting props...