What do you guys think the best prop is for this motor. Tried the 20x13 but did not feel that it had enough speed. ANy other props you guys can think of? Also did not set the brake, and had a difficult time landing the bird with the prop free wheeling. Will adding the brake help with this?


TIA

HI,

Did you set the timing of the controller to the highest value? I'm running the Hacker Acro 90 with 30 degrees of timing, this really brings the motor alive.
and provides a big enough speed range. For really calm wheather i'm using a 21x12 APC-E, works fine aswell!

About the slowing down before landing, i'm slowing the plane down a lot on final, and then fly it in with some power. This high nose attitude makes beatifull landings.

Good luck
Winfried

I'm running the std Jeti 90 and 77 with my AXI 5330/F3A (235 kV). I believe the Jeti defaults to 24 degrees timing if set in outrunner mode and I have more than enough power and speed running 13" pitch props. 12" is great in calm air, 20X13 or 21x13 for some breeze and 20x15 for WINDY. The plane is ballistic with the 20x15......

If you are running the low kV 5330, you might want to try a 14" or 15" prop.

Don

Thanks for the input guys, I believe that my timing is set to 24 degrees. If I increase this to 3o will I get better result speed wise, and also will having the brake on aid with landing. Also what are the best settings for idle?

TIA

I like the 20x15, but I really haven't played around with other props. I did try a 20x13 or 21x13 (can't remember) and had the same conclusion as you in that it felt too slow for me. Woodie's right, you can get going pretty fast with that prop, so throttle management is a must.

Emory.

Robert don't let the prop freewheel, I use a little idle and works perfect. I liked the 21X14 prop in wind and calm the 22X12.
Steve Maxwell

Anyone use the brake?

The brake function on the standard Hacker and Jeti controllers only stops the prop. The competition Hacker and jeti Spin have programmable brake. I am using the standard Jetis so no programmable brake, I just set idle as slow as I can get and then usually have to add a little throttle to control sink rate on landing.

Woodie

I have a Spinn 99, and I can add the brake. I was just curious as to what the brake would do?

With a programmable brake (Spin series or Hacker Competition series), you can tell the controller how much brake it should apply to hold a constant rpm on a throttled back downline or some deceleration maneuver. You can have a small amount to a large amount or even stop the prop. Stopping the prop acutally creates less drag than letting it freewheel.

Woodie

What about running it on a three blade?
Ive seen a few electric pattern planes running 3 blade props, Im assuming its in an attempt to get it to slow down on the downlines.

You might want to talk to Tony Stillman. He has a Brio, and I think hes using the Axi. He should be able to give you some good input. I cant remember if he's running a 2 or 3 blade prop.

Edit:

Dan Landis used a APC 15.75X13 3 blade in the F3A Nats on his Axi 5330/Brio
Here is his set-up
Axi 5330
CC 85HV
Tanic lipo
68 amps at 7800 rpms - 2200 watts
Engine Temp after landing was 148F
Battery Temp was 122F

Scott Anderson uses a APC 18x12E on his Axi 5330/Focus II
Here is his set-up
Axi 5330/10
CC 110HV
MaxAmps 10s2p 4200mah
69 amps at 6250 rpms - 2200 watts
Battery temp was 130F

Alright guys, went to the field today to fly, so I fgure that I would charge before I left home. I use the 1010 C charger and 10S 3850 batts. To my horror, when I was charging the first set I put 3700[:@] back in the pack. I did not push the motor at all and when though the Advanced sequence once and landed. What the Hell. I am sure my flying style is not that hard on the Batts, any thoughts on my dilemna? I am very dissapointed with this result. Still went and flew, and the batts seem to do fine.

Sounds in the ball park.
That's about what I was getting last year flying the advanced sequence with my Brio.

AXI 5330/18 (not the F3A version)
APC 15.75X13 3 blade
CC 110HV
TP5300 10s
10.9 lbs

---Derek

Edit: I went back over my notes and see that I typically use 3300-4000 on 8 minute practice flights and 2400-3000 on 6 minute contest flights, depending on the amount of wind and pilot excitement level. So yes, perhaps you might be leaning on the throttle a bit too much. On my Brio, at least, there seems to be a sweet spot where you can keep the momentum going, but reserving full throttle only for uplines. The last 1/4 throttle seems to make a big difference on battery temps/consumption but little difference on speed.

I agree, there seems to be a range of throttle settings that maintain good speed without drawing as much current. I can fly the P07 sequence (APC 21x13) with good speed and nice maneuver size at about 3500 mah if I keep the throttle at the bottom range of the 'good speed' settings. Or I can use 4200 if I leave the throttle at a higher setting thru out the flight. And there isn't much difference in the speed and vertical performance. Seems that there is a sweet spot for each prop configuration.

I have flattened the mid range throttle curve so that small changes in throttle stick position create very little change in amp draw. I know, I have used the radio programming to compensate for what I should be able to do manually, but it works easier this way.

Something that might help find that sweet spot, is to reduce your throttle ATV until you notice a reduction in overall power then bump it up just a little and you will probably find the last 20% or so of your throttle movement doesn't create any noticeable increase in vertical power or horizontal speed. However, it will still increase amp draw. Might take a little playing with your throttle curve to find the right 'feel' for your particular style flying.

Flying electric has a pretty steep learning curve with it but the nice thing is, it is easy to experiment with power setting and the results just by changing your radio settings. Something else I would recommend is getting is some type watt meter or logging device to fly in the plane just so you can see the max amps during a flight. I use the WattsUp meter and like it for instantaneous readings and it will record max current, minimum voltage, etc. Recently, I have started using the EagleTree MicroLogger and it is very useful to see the affect of props on current, rpm and battery voltages and temps. If you haven't seen the results of a logged flight, I attached a chart from one of my test flights.

Don

Woodie I have the Spinn box, that tells me all that good stuff. I charged the batteries after I got home from flying and put back 2300 and 2500 Mah back into each pack. This leads me to beleive A. that I did not charge the pack properly or B, did not give them the proper break in time. Will continue to fly and see how it goes.

After flying today, 2100 Mah back pack 1 and 2400 Mah back pack 2 giddi up!
Thanks again guys for all your help

Now you're talking!!!! Go get 'em......

Don