Full Speed RC Leader 3 SE Review Part 1: OVerviewand setup

The Leader 3 SE from fullspeedrc.com

Introduction
The Leader 3 (SE) is a follow up to the hugely successful Leader 120 which I have reviewed and documented modification extensively, most recently with a summary here. Both are available from Fullspeedrc.com This has been a highly anticipated release not least of which because there has been no releases from Full Speed since last years' Beebee 66 light. The good news is that a big chunk of that wait has been spent working on the Leader 3. FYI two of the main guys are pilots from Full Speed RC are pilots and do a lot of work testing before release which is a welcome change in this hobby compared to many models that come out half-baked.

Firstly the Leader is available in 2 variants. The standard model (Leader 3) can be seen below and weighs 87g with regualar standoffs. The Leader 3 SE is exclusive to Fullspeedrc.com and comes with a 3d printed canopy instead of the standoffs. It is 6g heavier but offers several benefits that I'll cover a little later on.

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A run through the components
First the frame. Like the Leader 120 the base plate of the frame is 3mm thick although it has been stretched to 130mm motor to motor diagonally rather than 120mm This means it is capable of accepting a true 3" propeller rather than 2.8" maximum on the Leader 120. The frame is most definitely still a 'deadcat' shape meaning the two motors are further apart (107mm) than the 2 rear motors (98mm). Additionally it is a 'squashed-x' compared to a 'stretched-x' meaning the front and rear motors on the same side are closer together. This means it should be more stable in the roll vs. pitch axis but modern flight software somewhat negates this. Compared to the leader 120, sideplates have increased from 2mm to 3mm thick which should aid durability. More imporatantly a 19mm gap rather than 17-18mm means the leader 3/SE now natively fits a 19mm micro cam. It's worth nothing that the baseplate is only 1 piece so you cannot replace single arms. Personally I think replaceable arms are unnecessary on any quad size less than 4" since there is much less leverage for breaking on a smaller quad. The frame can be purchased separately here.

107mm wide motor to motor at the front

98mm wide motor to motor at the back

130 - 131mm diagonally motor to motor

The canopy (Leader 3SE only). When I first saw the canopy I wasn't keen because it adds 8g weight however I think the functionality may just offset that - jury is out until I fly it some more. The 3d TPU print is of very high quality available in black,white, red, purple, blue or yellow and performs the following functions:

• Replaces the standoffs
• Provides strain-relieve for battery wires
• Provides positive mounting and protection for VTX and receiver antennae
• Sharkfit provides a fulcrum for flip over after crash (anti turtle) mode.
• Provides protection for buzzer/LED unit
• Looks tidy.

The motors are 1106 4500kv which is the same specs as those found on the Emax Babyhawk R 3 inch and the Skystars X120. They are not open bottom and have mounting holes for regular t-mount props and the emax 2.3" avan props. Most importantly they are rated for up to 4s.

The stack is a Fullspeed FSD F428 flight tower. The flight controller has a F411 chip and will run up to 8k gyro loop and so requires little in the way of soft mounting. The BEC onboard is 5v 3A. It looks to have a pad for current sensing which is good news if you are wanting to use this funtional although you'll need to use something like the FSD Amass XT30 Current Sensor since the ESC does not have native current sensing. Speaking of the ESC it is rated to 28A, runs BLHeli_S and most importantly is capable of 2-4s. The stack can be bought separately here.

The VTX is a brand new unit that has only just been released by FullSpeed: the FSD TX600. This is a 20mm x 20mm stackable vtx that is switchable between PIT/25mW/100mW/200mW/400mW/600mW. All parameters can be controlled via betaflight/butterflight OSD via the IRC Tramp protocol. I'm looking forward to trying it because the test DVR that I've seen looks to be extremely clear. It can be purchased separately here

The camera used is the Caddx F1 which uses at 1200TVL CCD sensor. I've not used this particular one before and am looking forward to trying it out. FullspeedRC sell the camera here for only $15

Propellers included are the HQ 3x3x3 At present fullspeed recommends these on 3s and the 2540 on 4s in summer. I'll be trying the included props on both 3s and 4s since it is winter where I am. Available here

Receiver: I requested a frsky receiver and FullspeedRC included their own model - a d8 based FSD frsky nano V2 which I've reviewed here (although this was the V1 version) The v1 has better range with a proper dipole antenna and broadcasts RSSI over channel 9 by default. This can be bought here - also available in spectrum and flysky flavour.

The Build
Like the original Leader 120, build quailty is excellent. Solder is clean, wires are cut to length. Not much more to say here, it is well beyond my ability! With the quad assembled there is plenty of room behind the camera to adjust tilt (45° and beyond are capable) and the receiver is mounted in this void. with plenty of room left yet. This is speculation but I'd like to address anyway since it seems like a common thread: my best guess is the caddx turtles HD FPV/DVR (not yet released at time of writing) will fit but not without a little modification. My reasoning is that there seems to be 2-3mm 'spare' room between each stack layer. If these standoffs are trimmed by this amount you will be able to save 6-9mm in height which should be enought to fit the turtles board. It will require some fine wire management and a steady hand to trim the standoff but I do think it may be physically possible - a project for another day. That being said, the double stack of the runcam split micro definitely will not fit.

I think I can get 2-3mm off each layer of standoffs here - enough to make room for a Caddx turtles maybe?

Software setup
Plenty to talk about here although most can be foundin commentary of the Betaflight screens below. If you don't choose to read these however:

• This flight controller has a unique target that is supported in both betaflight and butterflight: 'FULLSPEEDF411'
• Ships with Betaflight 3.3.3
• It is the most customised betaflight I have ever come accross. Custom PIDS for 3s (profile 1), 4s (profile 2), buzzer, OSD, arm angle etc. etc. A lot of thought has gone into this.
• Hex files for betaflight 3.3.3, 3.4.0, butterflight 3.5.0 are available here

Final thoughts pre-flight
As you can see from above this looks to be a very well thought out quad and not something slapped together from a spare parts bin. The Babyhawk R and Skystars bolt X120 have both shown that 1106 4500kV motors perform well on 4s in 2.5" and 3" so I am excited to see what the Leader 3SE will add here with all the work that has gone into development from a hardware and software perspective. On paper this looks to have the edge on both of those models in terms of weight, VTX capability and ESC current overhead however the real test will come in flight - stay tuned for part 2 of this review where I will cover flight in full - I already have 3s and 4s batteries charged for tomorrow :)

The Fullspeed RC Leader 3/SE can be bought directly from Fullspeedrc.com and is also available at other retailers however buying from the source is your best chance to get your hands on one quickly.

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