AeroScout Prop Test Part 4 - Micro Draco Prop!?

[@JohnMcClun]

Thanks for doing this 4 blade prop.

[@txkflier]

I finally measured the pitch angle of a known prop and got the correct pitch. I used an APC 6x5.5E which should have a pitch angle of 21 degrees at the 75% point of the blade length. 5.5 / 6 = 0.91667 0.91667 / 3.14159 / 0.75 = 0.3890 A-tan(0.3890) = 21.2 degrees I measured the angle as 21 degrees by rotating the photo I took looking down the blade from the tip. So, I’m sticking with the stock prop being a 5x6. I wouldn’t use that kind of prop on anything except a very slick racer.

[@davemcddd]

Good info! A buddy just test flew his Micro Draco today at my local flying field. He also has a AeroScout. I'll have to let him know that the Draco prop will also work on his AeroScout, and will work better than the stock one. I'm hoping Master Airscrew has a sale soon to order the 6x3.2 3 blade props.

[@shanesdiy]

I contacted them trying to find out how many of the 6x3.2 props they sold after my videos but got jo response. So many folks have told me they ordered several of them and love them. They must have sold dozens of them.

[@TheCasualPilot]

How are you getting the ammo draw and rpms on tune radiomaster. Is that telemetry coming off the esc? Is it the stock esc? Is it a stock receiver? I have the first gen aeroscout. Not sure if it has the same esc and rx as the gen 2 version

[@shanesdiy]

@@TheCasualPilot in this AeroScout I upgraded to the Avian Lite ESC that comes in the current version of the AeroScout. If you go back through my videos I show it in my AeroScout reverse thrust video. It adds telemetry. I did need to tune both amps and rpm telemetry values to get them to read accurately. I'll probably do a video on that process soon.

[@staydown.normal5323]

i made a inav aero scout years ago. 5x4.5 bull nose is the best. change the motor if you want to a 2450kvBrotherHobby LPD 2306.5 or 2207

[@cozzierich]

Appreciate all of the testing you are doing on AeroScout props. Just wondering for correct reading of the RPM telemetry sensor "Erpm", besides setting the poles to 14, did you also have to use a multiplier of 2?

[@shanesdiy]

Actually it ended up being set for 7 poles, multiplier 1. I verified it with a non contact tachometer. Odd, I wasn't expecting to use 7 poles but that's what matched actual rpm.

[@cozzierich]

@@shanesdiy All of your testing motivated me to do some prop testing of my own. I am at 7200ft elevation so my numbers using many of the same props you used were not as good in the static tests. I decided to switch out the motor to an EMAX ECOII 2306 2400KV. This has a shorter clockwise thread shaft so the M5 locking nut I used was a lower profile 4.5MM. On some of the props I was pulling 30 plus amps on the avian 30A ESC which isn't safe for sustained use. I settled on the MA GF 6x4 which seemed to be the best balance of efficiency and thrust. Final numbers for this prop were 840g, 25Amps, 24.4K RPM. Just for reference the best prop in terms of thrust was the MA 3 blade 6x3.2, 945g, 30.5Amps, 22.2K RPM. This prop would probably work out really well if I ever decided to upgrade the ECS to an Avian 45A for example. One other test I did for fun with the original motor was run the MA GF 6x4 on a 4S 1800 battery. The numbers were 980g, 26A (never recorded the RPM but I am sure it was somewhere around 28K+)

[@joeg986]

What size drill bit did you use to open it up? Thanks.

[@shanesdiy]

#8 / 5.05mm is best

[@joeg986]

@@shanesdiy Thank you very much.

[@1964markw10]

Could you (If you haven't already) put a pdf out of the data you have gotten so far, out so I don't had do to screen grabs etc .... ?

[@shanesdiy]

Good idea! I was thinking I needed to build a spreadsheet to keep track of all this. I also had to go back to a previous video to confirm the stock prop thrust and amps. I think I'll start a Google Docs spreadsheet and share it in the description, would that work for you?

[@shanesdiy]

Check description for link to the spreadsheet

[@1964markw10]

​@@shanesdiy Thanks, that would be great.

[@staydown.normal5323]

im using i nav on all my planes the aero scout has inav 4.1.0 and I know from gpd speed and amps in the ods that the 5x4.5 bull nose is the best for speed or long range it dose not use that many amps dosent over heat esc or motor and I get 7 to 10 min fun flying or 20+ if i just cruise 1500mah 4s 120c

[@txkflier]

At 20,455 rpm with a pitch of 3.3", that's a pitch speed of 63.92 mph (20455 x 3 / 1056 = 63.92). It would be interesting to know the rpm and pitch for the stock prop.

[@shanesdiy]

I'll get the stock prop static rpm for you later today. How do you like the new telemetry screen? Any other data points you'd like to see on there before I do more climb and speed runs?

[@txkflier]

@@shanesdiyThat screen is great. I think it's good like it is. What is the diameter and pitch of the stock prop? I couldn't find it.

[@shanesdiy]

Stock prop 19307 max static RPM, 5" diameter. Haven't been able to find any data on the pitch yet.

[@txkflier]

@@shanesdiyWell, if I knew the angle of the back side of the blade at 75% of the blade length, I could calculate it.

[@shanesdiy]

@@txkflier I'll see what I can figure out. Would be nice to have that info.

[@goldenson808]

It sounds painful to go full throttle with this propeller lol

[@shanesdiy]

What do you mean? It's the quietest prop I've tested and I've tested a lot of props. If you have one and are testing it, be sure it isn't on backwards, it makes a terrible noise running in reverse! The black painted side of the tips needs to face forward (front of plane).

[@goldenson808]

Oh OK I think I did have it on backwards, it just came apart on me today in mid flight

[@oldponytail]

That prop looks to be on backwards.

[@shanesdiy]

No sir, be sure the black painted tips face the front of the airplane if you decide to try this. If you try to run it in reverse it makes a terrible noise and vibration and will most likely explode since it's so weak.

[@goldenson808]

Using 4s the draco prop just broke in pieces.

[@shanesdiy]

It is a very thin prop, not surprised. It ran over 20,000 RPM on the AeroScout 2250Kv motor on 3S, I would not consider trying 4S with it. What airplane/motor were you using? With the AeroScout 2250 motor on 4S that prop has the potential to hit 27k-30k RPM!

[@goldenson808]

Just the stock motor. What other prop would be better to use that would perform and be as efficient with amp draw like the draco prop?

[@shanesdiy]

I have several prop test videos so far, still one more to go on the AeroScout for all the flight testing data then on to some of my larger planes. In the video description there is a link to my data spreadsheet with all data collected so far. Look for high static thrust and low amps. The two props below are good choices. The Master Airscrew 6x3.2 three-Blade at this link is still a favorite for max static thrust. bit.ly/495r736 The Master Airscrew 6x4.5 two-blade drone racing series actually had slightly better static thrust than the Mini Draco prop and almost the same amps. This is slightly more efficient than the Mini Draco prop and much stronger. Comes in a 4 pack so you get two with the correct rotation for the AeroScout. This is the green one but you can get this in black, orange, white, or green. In another video you can see the static thrust testing of this one. bit.ly/3ykL7lR

[@staydown.normal5323]

4 blade prop sucks 2 blade bull nose 5x4.5 bullnose for the win

[@shanesdiy]

Been testing many props. "Best" depends on what you want it to do. Top speed, stock seems to be retaining the lead so far. 3 blade 6x3.2 has much better rate of climb and shorter takeoff roll. Still more data to collect. Changing the motor would defeat the purpose of this series of testing. I want to see what performs best with everything else stock.

[@staydown.normal5323]

@@shanesdiy the stock motor with stock prop turns black After it has been flow more then 30 times it's not the best

[@staydown.normal5323]

@@shanesdiy top seed for my home made toys is 133 mph . Average 100 mph on 4s 40amp esc 5x4.5 prop 2450kv 2306 sonic modell fixed wing . Tri blade props are for drones to turn better to help speed wobble the are poop for planes no thrust

[@shanesdiy]

@@staydown.normal5323 That's pretty fast, what airplane? 100mph AeroScout would be crazy! These tests are to see what someone can gain by a simple prop swap in 5 minutes and under $5. Best performing prop so far has been a drone prop based on measurable data, static thrust, rate of climb, amperage draw, etc. Top speed is not the only parameter I consider to call a winner. Swapping motors, ESC's, etc is a subject for a different video series. Apples to oranges.

[@shanesdiy]

@@staydown.normal5323 Not sure what you are referring to, I have way more than 30 flights on my AeroScouts and the motors look good as new. Pretty sure no one has ever called the AeroScout stock motor the "best". Sufficient at best 🤣