New E-flite P-51D 1.5

[bobtheman]

Hot mother generally is

Prop too big or too much pitch

Not enough cooling

Or HH got the current draw esc output wrong which sorry to say is nothing new with those clowns

Either way it goes don't fly it till they make good which they won't cause they suck

Sorry for your troubles

Thanks for your input they sent a replacement motor and ESC hope this will cure motor hot enough to cook an egg

[bobtheman]

Hot mother generally is

Prop too big or too much pitch

Not enough cooling

Or HH got the current draw esc output wrong which sorry to say is nothing new with those clowns

Either way it goes don't fly it till they make good which they won't cause they suck

Sorry for your troubles

Thanks for your input they sent a replacement motor and ESC hope this will cure motor hot enough to cook an egg

[Johnnyrabuse]

Add some venting in the cowl punch a few holes with a pencil

[406PIlot]

Has anyone take this eflite p51 and swapped it over to a 2 blade prop? Wondering what spinner and prop size were used if anyone has done this.

[bobtheman]

Add some venting in the cowl punch a few holes with a pencil

I am wondering if anyone else has found that the motor runs super hot!?

[406PIlot]

I have only 8 flights on mine, but haven't noticed a hot motor or ESC yet. I'll keep an eye on it after each flight and see. It's also getting cooler since winter is starting to set in. This probably helps with the temps so I might not get the most accurate info for normal operating conditions.

[Johnnyrabuse]

I am wondering if anyone else has found that the motor runs super hot!?

Just remember if the rear venting exit is blocked by wires or battery or anything else it will effect the airflow

I've had this on the FMS 109 and the dynam mustang

[bobtheman]

Just remember if the rear venting exit is blocked by wires or battery or anything else it will effect the airflow

I've had this on the FMS 109 and the dynam mustang

Thanks for the info I will take a look

[406PIlot]

If I was going to change the prop on this plane to a 2 Blade for some better efficiency and a little more speed does anyone have a recommendation? Has anyone done this previously and can share their experience?

The stock 4 blade prop is a 15.5 x 11. I was thinking if it was swapped to a 2 blade you could easily run a 16x10 or 17x8. Does anyone have thoughts on Input on this?

[paladin]

well the pitch is what gives you speed so 16x12, to keep the same speed 16x10.

Joe

[406PIlot]

Appreciate the Info. I think maybe I'll start with a 16x12 and see what the numbers look like and go from there.

Thanks Paladin.

[paladin]

MENY YEARS AGO AMA RELEASED a formula to compare props. the theory was if you had a prop that worked you could find a different prop that would load the engine/motor equally. it seams to be a derivative of the hp calc, so I found it to be reasonable.

p times D squared = PD2

so in the case of your 15.5 x 11 => 11(15.5x15.5)X2 x2 is because it is a 4 blade (a three blade would be X1.5) = 5285.5

16x12 = 3072
18x12 = 3888
20x12 = 4800


the 4x blades loos some because they are in turbulent air so exactly how much the rounding should be I will leave to you. but a 16x12 should see an improvement in rpm which again goes twords speed.

Joe

[406PIlot]

paladin This is great info!!! Thanks a ton. I'll start experimenting and checking static numbers with the amp/watt meter. Soon as the weather breaks i'll get out and test things in the air.

[406PIlot]

So had this plane out yesterday. I was going to do some T&G's on my second flight of the day with it. And what do you know the gear wouldn't come down. I tried to cycle the gear for the last 3min of the flight and got nothing but the gear doors opening and closing as they should. But no gear would come down. Not the tail wheel or the mains NOTHING.... Ended up having to belly land it. Fortunately the belly landing went fairly well. Only ended up with 1 broken prop blade. No wing scratches or anything just that a single prop blade.

Get back home and do some testing and turns out the gear / door sequencer was causing the issues! Sometimes if I pinched the sequencer or wiggled it just right the gear would cycle. Sometimes 1 main would come down other times both, but no tail. It was all over the place. Individually testing each retract including the tail and they all work just fine.

I only have 12 flights on this plane. I'll be contacting Horizon Hobby to let them know about this.

[406PIlot]

So tested a few props on this and found the 17x12 to work really well. Max draw of 75amps. The speed seems to have increased some, but without a radar gun or GPS telemetry sensor I can't give hard numbers on the increase. I can only say it seems to be faster.

I also tested an 18x10 that worked really well. The Max draw on this prop was around 96 amps. It may have been equally as fast as the 17x12 but again to hard to tell visually.

The 17x12 is what I'm sticking with for now since it's not as close to the max esc rating for amp draw. It also isn't physically as close to the ground during take off or landing so there is less chance or catching the tips on the runway.

[paladin]

well, the big advantage of a 4 blade prop is vertical and it looks cool when sitting still on the ground. I use 2 blade props mainly because I can get a longer flight out of them. at the point you r at I would fly it and get a burn rate (mah put back in the battery/time flying) then try a 16x12 then a 15x12 checking the burn rate for each.

flight time= (battery rating*.8)/burn rate= to dead stick time

I keep all my planes between 40-60amps because that yields a good flite life

Joe

[406PIlot]

well, the big advantage of a 4 blade prop is vertical and it looks cool when sitting still on the ground. I use 2 blade props mainly because I can get a longer flight out of them. at the point you r at I would fly it and get a burn rate (mah put back in the battery/time flying) then try a 16x12 then a 15x12 checking the burn rate for each.

flight time= (battery rating*.8)/burn rate= to dead stick time

I keep all my planes between 40-60amps because that yields a good flite life

Joe

With the 17x12 I'm still getting 5:30 seconds of useful throttle time. This is using my timer and it only counts down above 25% throttle. Using a 5000mah 50c 6S pack and landing at the 5:30 mark based on my radio timer the packs are coming off at 3.79, 3.78v per cell. This data is based on 3 flights with the 17x12 prop.


Last night I also clipped the wings on this bird!! I took 4 & 1/8th" off each side. It now has a wingspan of 1295mm / 51inches. I'll be testing how it fly's today. If all goes well I'll be painting this up as the precious metal p-51 Reno Air Racer!!






I'll post up flight results later this afternoon hopefully.

[406PIlot]

Well got out to the field this morning. It was windy, but I had to try things out. Turns out the plane flys amazing regardless of wind!!! the clipped wings made almost no difference in stability at all. Roll rate and over all handling are almost identical to what it was stock! I was completely shocked by that. Here are a few quick pic's




Now it's time to clean up the cuts and get it ready for paint. I'm going to smooth everything out and paint it up as the precious metal reno air racer (Chrome & Yellow).

I'm super pleased with out clipping the wings turned out.

[F106DeltaDart]

Just received the FMS version of the 1.5M Mustang. Pretty happy so far with how it looks.

[xviper]

Just received the FMS version of the 1.5M Mustang. Pretty happy so far with how it looks.

Where did you get one of those? Neither Horizon nor FMS even has it listed. Anything different about the FMS version?