The Flyfox 110mm is a BNF Micro 2 inch quadcopter for newcomers HobbyCool.com. I was most interested in this micro quadcopter because so far as I can see, the BNF model here is completely exclusive to HobbyCool.
The frame is based on a 3mm bottom plate with 1.5mm sideplates attached by tabs and 3d printed standoff - very similar to the Leader 120 but with a different look and more importantly, a factory micro CCD camera. The frame with hardware on its own weighs 15g and is available here for less than $10. Speaking of the camera, it looks to be nicely protected by the frame without impacting the view however only a limited amount of camera angle is available as can be seen in the image below:
Electronics are fairly typical - F4 flight control and 20A DSHOT600 ESC. 2 nice suprises I was not expecting here though - tramp control of VTX (my first in a micro) and a baromoter in the flight controler (my first altogether!). ESC uses a JST connect which should be ok although I would have preferred a XT30. Voltage drop may or may not be an issue but in practicality in all except my lightest brushless quads (less than half this weight), it is a much more robust and convinient connector.
This quad is PNP so does not ship with a receiver so I used my favourite XMPlus for FRSKY. It does however ship with a nice 550mah 2s GNB battery which unfortunately for me is still with Hobbycool since getting batteries to where I live (NZ) is getting harder and harder. Lastly a buzzer and 2 x programmable LEDS are connected and mounted and 16 x Kingkong 2035 4 bladed props with screws are included.
All solder joints that I could see looked to be good, wires were well trimmed, routed and secured and the build quality looked good.
All up weight including props, battery strap but no battery is 78g which is heavy but it's worth noting that this is in a power class of it's own with these monstrous motors.
When I first plugged in betaflight configurator in I was expecting to see a dead stock list of settings but was pleased to find some customisation - see below for a list of stock settings which included a number of modes set, craft name, DSHOT600 etc but unfortunately no custom PIDs (or rates). Prior to the initial flight the only changes I made to setting were for my receiver with RSSI set to channel 16 and my stock modes - arm-disarm; angle-horizon-air; beeper off-beeper on.
Getting ready for FPV Maiden
Even before I started FPV I could tell from the hover test that the PIDs were too aggressive by the excessive fluttering I could hear. This is to be expected because the comparitively large motors have absolute control of the motors and so the feedback loop is exaggurated. I knocked P, I and D down for all three axes to get it in the air without risk of damage but it could certainly do with some more tuning to crispen up the controls. Since it was Betaflight 3.2.0 that was installed, PIDs were easily changed via OSD.
Since I did not have the stock 550mah 2S GNB battery (which is highly regarded) I used my turnigy bolt HV 2s 500mah 65c batteries charged to regular voltage with stock jst discharge connectors. For what it is worth, radio was FRSKY QX7s and goggles were the AOMWAY commander V1s. Takeoff weight was 104g
The quad powered on without issue and I was off flying immediately. I started with the stock propellers but switched the the Gemfan 2035 4-blades after finding that they had a bit more top end through a wider blade at the tip. Power was predictably high for a 2 inch but regardless of the large motors lacked a bit compared to a quad swinging a 2.5 inch prop (e.g. leader 120, HGLRC Hornet, Mini Fight). Update: After more time with the Gemfan 2040 Hulkie 3 bladed props I found I was able to get better performance again out of these 3 bladed props over either set of 4 blades. As I suspected when I first reviewed the hulkies, their stiffness and less blades are better suited to a high power setup.
Due to the large motor size response was excellent but given I tend to have a preference for light weight over power I found that hard flying took quite a toll on the batteries. For moderate to heavy flying I found I got about 2 minutes of flight on the 500mah batteries, which recovered to about 3.73 v per cell on resting. During flight though I did get a lot of warning of battery low and land now but in reality just need to change the battery voltage hysterisis setting to be a little more tolerant - article on how to do that here. Update: 15 packs later I consistently get 2 minutes on these batteries.
It is fair to say that between the large stator height of 6mm and very high kV of 7800, this motor is designed for 2s and no more - even trying 3s did not cross my mind... not only because of the likelihood of the motor cooking itself but because you simply cannot take advantage of it with the 2 inch props - it will just make more noise and heat.
Batteries and motors aside, the quad feels like any other high powered 2 inch - powerful but certainly not floaty where you need more throttle to make it change direction. Camera performance was on par with other CCD micro cameras including the Runcam swift micro, Foxeer arrow micro, HGLRC Elf, Furibee MS 1672. Video signal was good - typical for a dipole but like that it had the option of switching by 25mW-100mW-200mW via tramp protocol in the ESC. To be consistent with other reviews I stuck with 25mW. It's worth mentioning that when the vtx dipole is laying flat against the quads as in my pictures the reception is poor. Even when I temporarily bent it up performance improved a lot, but will cover this more in my list of recommendations.
The Flyfox 110mm BNF from Hobbycool is a high powered 2 inch drone that is well built and fairly priced at $129 the time of writing. It's key feature is the massively powerful 1106 AOKFLY motors that are fast but make the quad heavy and limits battery choice to 2s, even though the electronics can take up to 4s. These features make for a fast quad in a straight line that needs extra throttle in corners to help keep a line. The downside is that battery life is shortish - 2 minutes flat out on a 500mah battery. The kit is well provisioned with 16 propellers in total and a very nice 2s 550mah GNB battery.
The FlyFox 110mm BNF Micro brushless quadcopter is available exclusively at HobbyCool.com I'd like the thank Kevin for the sample he provided for me to review.
In this review I set out to build an ultralight micro brushless quadcopter based on the 16mm FULL SPEED Baby 2S F3 Flight Tower. The goal was to get less than 40g with a full featured brushless micro. Previously I'd achieved 41g using a smilar setup with a 2 and 3s capable 20mm flytower but found that the weight penalty of the 3s battery did not give back in performance on the little 1103 motors. More details on that quad on my rotorbuilds page. Please bear in mind this is not a simple build - motor wires are extremely fragile, solder pads are small and space is super tight, even with micro components. The outcome however is might impressive but I'll get to that more later.
I won't go into detail about why I chose the other parts but will list them here:
For the build itself I shelved the stock standoffs for the fc/esc since I wanted it super low profile. Instead I used 20mm nylon m2 screws with nylon m2 nuts and m2 orings to get the height I wanted. See my article making a low profile micro stack. I had to mount the ESC upside down and the flight controller rotated 180° about yaw in order to stop esc connectors touching and limiting height reduction. I also went through the painful task of cutting, tinning, soldering and heatshrinking the ESC signal cable to get it as short as possible - not just to reduce weight but because I have so little room to work on this build. I stuck with a JST connector and a short run of 20AWG cable since the connector is much lighter than an XT30 and it won't be passing a lot of current anyway.
I'll make a quick note that I used a AIO camera VTX since for this build I decided a superior micro CCD camera like the micro swift adds too much weight for me. The CM275T is the best of the bunch for me at the moment - it is very light at 3.3g and it has standard wiring that allows for betaflight OSD. UPDATE: I never was able to get this to focus correctly so reverted back to an old Eachine TX01 modded for video in and out. I also used the ghetto antenna mod I wrote about here.
So what was the final weight? 36g! better that I was hoping especially since I know I can get another 0.5g off from a receiver swap and another 1-2g from a different camera mount. That can wait though as I want to focus on flying this now rather than building. Click on the pics below to embiggen.
Once I finished the tricky stage of completed the build, ensuring all wiring was routed to avoid possible prop strike, the flight controller was set up. This is a full omnibus f3 FC and BLHELI_S esc setup which means I get all of the best betaflight features - Betaflight OSD, Dynamic filtering, Anti-turtle, ESC beeps vis dshot command. The only issue I had here was finding the camera was NTSC rather than my preferred PAL meaning I had to move my OSD elements a little close to the centre of the screen.
Since this was one of the two quads I took with me on my Summer beach holiday I got a good amount of flying in with a chance to try some different propellers. I settled on the Gemfan Hulkie 2040 (reviewed here) but think the 1940 version of the same prop would be slightly better as the offer a little more clearance and the 2040 is slightly over-propped - a little too floaty with a big disc/weight ratio. I actually think a 2 bladed prop would be best here but cutting down a larger prop like the gemfan 3020 will mess up the geometry too much with that much trimming. I plan to try the gemfan 2035 quad blades with 2 blades removed at a later time. Just a quick note here that although in the past I found the Hulkie 2040 propellers to be brittle. Not an issue on this quad as the low weight means crashes have very little force. UPDATE: Have now tried the 2040, 2-blade 2035 and 1940. 1940 is the best prop for durability and performance. The 2 blade 2035 was ok but didn't give me the efficiency gains I was hoping for.
So how does it fly? I'm impressed. On a 2s 300mah weighing just 17g I get 3 minutes of hard flying time coming down at 3.8v per cell - would be easy to go to 4 minutes but I have plenty of these $4 batteries so it's not an issue to change regularly.
In terms of what can be done with the quad it just makes this little guy so much fun. You can fit in tiny gaps with good fine control like a whoop but the top end speed and power for acro make it something else altogether. It doesn't have the speed of a 5" obviously, nor the momentum for tricks but you can still put it where you want, when you want. What separates this from bigger, heavier 1104 and 1105 based 2" micros and more traditional 3" micros is the lack of weight makes it feel so much smoother and easy to recover rather than feeling like a flying brick - something I've felt in all BNF 2" quads 55g and up and in traditional 3" quads like the Furibee X140 (review here) and the GEP RC Sparrow MX3. So far as bro-science is concerned this is not to do with power to weight (for example the GEP sparrow has wicked power/weight with those big 1408 motors) but more to do with disc loading - the area of a 2" is very small and can only support a small amount of weight. Even stepping up to 2.5" allows a lot more weight to be carried for a simlar feel (e.g. the Leader 120). In his own rambling way Bob Roogi does a good job of explaining this further here.
After flying exclusively with ccd cameras now I forgot how AIO cameras struggle with light handling. It's not a fault of the VM275t in particular which does seem to be one of the better of the bunch, just the particular CMOS technology used in these cameras. On a good sunny day it is not an issue though and on the cloudy days it is something you can get used to. If you did want to go CCD though I'd recommend swithcing to a micro CCD, FSD TX200 vtx and the FlexRC Ascent frame for an all up weight penalty of about 8g - not my objective for this build but may suit you better depending on your application. Albert Kim actually did a build similar to this in his video here.
Coming back to this review being one of the flytower though I can thoroughly recommend it for a lightweight 2s only micro build. The only equivalent that really comes close is the HGLRC Zeus which is 2-3 times the cost and won't fit in small frames like my Eyas build, although it is capable of 3s @ 16A. I'd also like to suggest that the 1103 motors seem to be a good match - they are as light as 3g each and will not stress the little 6a ESC. I'd very much like to try this combination for a cruising micro with a 2.5 or 3 inch superlight frame to see what kind of flight times I can get but for now, this small and ultrlight quad comes with me practically everywere.
UPDATE November 2018: It's hard to imagine I've now had this almost a year now and it is still going strong many crashes later. I've settled on the Gemfan 1940 props as the best in this configuration and the Fullspeed FRSKY nano receiver with weight down to a hair over 35g. Current hype is all around the 2s whoops and (Mobula 7 in particular which I'm in the process of reviewing) but objectively speaking this build is superior outdoors because:
Here is the latest image: