Turbines vs EDF
 

Hey guys not sure were to ask this question but I'm having 2nd thoughts on my original plan. I'm restoring a Byron F16 I just got done fiberglassing the wings ,etc moved the servos into the wing and rudder

I was going to use the byron fan with a Jet Screamer motor on 12s with a Castle 160amp ESC
well my motor showed up this weekend and the motor (not the fan etc) weighs almost 3 pounds!
and I was told I will pull around 130amps at 17pounds thrust.

But I also have an old AMT 180 pumped to 17.5 pounds sitting around,

So I know turbines have a lot of eflux but electrics are supposed to be lighter but in this case I think this heavy edf will be close to the weight of the AMT

so anyone ever convert there large EDF to turbin or the other way around?

what are your thoughts?

thanks

The AMT is a thirsty turbine, but so is an EDF system. Fuel weight reduces with flight time, EDF batteries weigh the same. The tail tube of an EDF set up is a roll of plastic tube, a double wall turbine tailpipe in steel and alu is heavier. Gear needs beefing up to cope with the heavier take off weight on the turbine. The Byron set up was not designed for turbine power, weight speed. Even your EDF will be heavier than the original which would have had 30oz of fuel maximum, but less so than a turbine conversion.

I'd stick with the EDF set up.

I don't necessarily agree with Dave.

Your AT-180 isn't anymore thirsty than any other 80N class engine. BUT... they are CRAZY heavy. The engine is heavy, the ECU is big, and the fuel pump looks like it came out of a Mack Truck. (lol) If weight is an issue, then an engine like a Wren SS will be better. (you will save over a pound, and have the same power)

As far as your comment, about "So I know turbines have a lot of eflux but electrics are supposed to be lighter" That's not true either. Batteries are still on the heavy side, when you need the "Power" of a turbine.

Dave has a valid point with the weight of fuel, and need to beef up the mounts for a heavy take-off. BUT... most likely, you will be lighter than an EDF on landing, after you burn that fuel.


Just an FYI... I have a little T-45, that was meant for a 90mm EDF. The guys who built them say they were 8~9 Lbs. My turbine conversion is under 8 Lbs with fuel in the UAT. So my landing weight is lighter than any of the EDF versions.


And finally... if you know you are building for a turbine... try to keep it as light as possible. Be aware of the parts you are using. BUT, then again... you don't always have to worry, since you will have WAY more thrust with a turbine over an EDF system... that weight may not be a big deal. (My Falcon 120 was only supposed to weigh 8 Lbs with a prop, but it's 22 Lbs wet, and flies great)

Post a couple pics of the project.


Just my 2 cents... take it for what it's worth.



****EDIT******


Because a turbine has such a high e-flux... you don't need the same power. Honestly, if you have 17 Lbs of EDF thrust to fly it... most likely, you can fly on a 60N class engine, and save even more weight, since you can carry less fuel.

Your motor is a waste of weight. On 12s you should use a scorpion 4035 or a het 800 motor. Much lighter like 2 pounds lighter. The big screamer motors are only good is you are going to 14s or higher with huge currents. Looks on rcgroups for bruff's threads on converting the Byron fan. Think he used a hacker heli motor.

ya I was was thinking that to. I guess I like these turbines so much - fill and fly.

And as a turbine flyer for about 13 years, lets not forget all the times when the turbine did not start good or at all, or quit in the air for some unknown reason, or has some kind of problem that makes it necessary to send back to the manufacturer for service and hope your bill is under $800. Plus shipping which can be expensive because of the weight. Oh, and you are hoping you get it back less than 1 month so you can enjoy your hobby.

I did a old Byron electric. What a waist. DO NOT GO electric. Its to draggy of an airframe and you need a very high throttle setting to keep it flying. No such thing as power off glide with a byron. I had 6500 mah packs with a BVM EVF in mine and it was a 3 min flight and land. Its a total waist. Go turbine 100% all the way.

Do away with the cheat hole, as Dave says u/c beef up and get that turbine bolted in.
Now look to see where you can get the fuel tanks in! You iwill need to get at least 2 litres of fuel in for a decent flight! Post your pics and this will make a good thread.
I like EDF but on a smaller scale (when I can't fly turbines), I love turbines, they push the boundaries of the hobby!


JT

Your the 2nd person I know know who did edf and was not overly happy. It seems like most who like the conversions are those who have never been bitten by the turbine bug

Ill be straight with you guys, the only reason I was thinking of doing this f16 in electric is because I'm in the Army and I know I only got 2 more years left in OH before I get moved who knows were. I have only been flying for 3 years and (my wife keeps me at a 10plane count) but a my planes are now Giant scale Topflight and turbines

my fear after reading on this site about all the places that don't allow turbines is I'll move and not be able to fly any of my jets.

I think ill be better off trying to get a used P120 or another 22 pound turbine to put in my Razor to replaces its AMT180 that's around 18 pounds

I know the amt 180 ant light but the byron to me won't go killer fast anyways

As one more person that converted a Byron F-16 to EDF I would go with a turbine too!! I only got 3 to 4 min flights out of it just like Gunradd said:( Mine came in at 22lb with batts. Here is a video of mine back in the day:) Thanks Billy D
https://www.youtube.com/watch?v=_Un1OZCLSm4

I flew some of the earliest large EDF 4 years ago. Constant issues with batteries not holding up, short flight times "if you flew it like a jet". My turbines are way better...you burn off weight during the flight, so they are lighter to,land. In regards to conversions of your Byron to turbine. I converted one of their F-15's last year, and it's flying just fine on a King Tech K-140. Beefed up the entire airframe, but jet flies great. (Guy from Chicago bought it and did a beautiful paint scheme on it!). I would definately go turbine!

i had a os 61 in my plane and put in a 61 electric it ran circles around the os engine nitro

I've done a bunch of EDF to turbine convertions and found that you need twice the thrust from the EDF to equal a turbine. So your 5kW 12S EDF setup would give the F16 the same performance as a 8lb thrust Kolibri turbine would. Imagine how light you could get if going with a 9.5oz engine and only 28oz of fuel(!) But most would probably want more oumpf then that, even though it would equal the 12S EDF.

Looking at it the other way around your 17lb turbine would make the job of a 34lb thrust EDF setup, that would be like 10kW. Probably over kill for the airframe.

The problem is the air frame. You can gold plate a turd but in the end what do you have.

True but it's more fun this way, I'm wet sanding the rudder right now.

I added dee carbon fiber spar to the wings, then sheeted with flight skin

i got some nice carbon fiber coth to add inside the fuze

Pic

I had a similar experience. When I flew glow I flew with an OS .61 2-stroke, an OS .91 4-stroke, and an OS .75 AX 2-stroke. All of those motors provided reliable power but when I replaced them with AXI 4120/14 and AXI 4120/18...........it ran circles around the OS engines. It was clean and fit into the cowl with no cutouts for a cylinder head or muffler. But I'm off-topic - sorry.

No electric props are very efficient

im selling my hanger 9 Jackel on this site , with a Eflight 700 size 500kv motor on 12s with a 11x12 prop it's doing 165+ with 4 min flight times with. 3300mah

its even faster than my boys falcon 120 with a VT80

Geez........12s with a 11x12 prop. How fast is that thing spinning? 15K? 17K?

Almost 15k unloaded. It's a blast. Some say it's around 170 but I like to error on less.

I have converted a number Byron jets to EDF. All using the Byron and building it stock. Only major mod I did is a battery tray for the flight batteries. No other mods. With the Byron fan I can build an F-16 for under 15 lbs. RTF. The stock fan on 12S using a Hacker A50-10L Turnado motor does 22500 RPM at 100 AMPS which is better than my OS 91 powered fan. I have converted the F-16, Mig 15, Top Gun F-15 and now working on Byron's BD-5J. I never owned a turbine so I can not compare. Just building it stock it will fly great as an EDF.
Bob

yep, and no generator running in the pits all day to charge the packs that are gonna last 5 min MAX!

i would put a turbine in it, just not that one. Nothing wrong with AMT but you need a lightweight unit. There's a PST 600r in the classifieds for a good deal, less thrust rating on paper but a great little turbine. I know guys that have those units and they seem to run forever. If you're really concerned about weight, convert it to an XICOY Fadec which is what all PST's come with now.

paulD

True! Here's a pic of me about 3 1/2 years ago just before I saw sense and replaced the EDF setup with a Wren 44 Gold. The jet now takes off 1lb lighter and lands around 3lb lighter than it did as an EDF, Plus it's cheaper to run, and there's no worry regarding the aggressive throttle management needed to protect lipos, esc and motor of an EDF setup.

i like turbines but will never get a waiver i fly in the desert where you dont need one>> there are a lot of other planes also that need a waiver to fly but dont have one> who ever thought this waiver thing had a hole in the head

If you don't fly AMA... then it doesn't matter.


BUT, I don't understand all the negative comments I hear about the waiver. It's not that hard to get, and it doesn't cost anything extra. If you are a good pilot... you go to your local CD, and you fly a few times... get a signature, and send in the paperwork.

It's just a way to be safe, and keep your insurance.