RS2205 4S propeller tests

I’m building a new race quadcopter since I want more performance than my current one (3S with 1804 motors). I decided on EMAX RS2205 motors with DYS XM20A ESCs. I went with the EMAX NightHawk 200 frame because I like the lower top plate to keep the CG close to the center. The 4mm bottom plate should be strong enough to hold for most crashes as well.

As usual when ordering from HobbyKing I purchased a few extra things, like a thrust stand (they have a newer V2 but since it was out of stock and I already own a power meter I got the v1).

So I decided to get a few different 5" props and do a comparison, unfortunately HK has annoyingly low limits until you get “parcel too big, please split into two orders” errors, so I could only fit 3 different types this time. I’ll update this post if I order more later on.

I’m running the motor from a 4S 4400mAh 65-120C to be sure that the battery doesn’t limit the current draw. I’m measuring current and effect with a Turnigy 130A Watt Meter and Power Analyzer that I can’t find on HK any longer. I’m also measuring the RPMs with a Turnigy Tachometer but I don’t know how good my measurements were, it seemed a bit flaky, maybe due to low lighting. I didn’t include all the data in these graphs, but everything is available in a Google Docs spreadsheet.

The props I tested was a spare EPP5030 from my old machine, a Gemfan 5045BN, a Gemfan 5046BN and a brutal Gemfan 5550BN. Note that the 5550 will not fit the EMAX 200 frame since it’s too large at 5,5".

Thrust graph

Current graph

I obviously wouldn’t recommend the 5550BN when using a 20A ESC since it pulls over 40A at full throttle, even the 5046BN is a bit high at 33,8A, but the 5045BN should be safe, since most 20A ESCs should be able to handle burst currents of around 25~30A.