Everything now goes together around the main plate. Steps 4 and 5 build the top plate assembly on the bench; Step 6 joins it to the arms and main plate; Steps 7 to 9 finish the aircraft.
#Step 4: Flight controller and telemetry radio onto the top plate
Parts: top plate, your flight controller, air-side telemetry radio.
Hardware: the double-sided tape supplied.
- Wipe the top plate clean where the parts will sit, so the tape grips.
- Stick the flight controller to the centre of the top plate with double-sided tape, arrow pointing forward.
- Stick the air-side telemetry radio anywhere on the top plate that suits your layout. Keep its antenna vertical and clear of the carbon.
- NDAA kit (RFD 900x-US): fit both antennas, at 90° to each other if you can. All cables are included.
- Standard kit (LR900-F): use the JST-GH cable supplied.
- Plug the radio into the flight controller's telemetry port.
#Step 5: Compute plate
Parts: 4 standoffs, compute plate.
| Hardware | Per standoff | Total |
|---|---|---|
| M3 × 6 socket head | 2 | 8 |
| M3 lock nut | none | none |
- Stand the four standoffs on the top plate at the holes that match the compute plate's corners. Fix each with an M3 × 6 driven up from the underside of the top plate. Hold the standoff so it doesn't spin. These screws thread straight into the standoffs, with no nuts.
- Sit the compute plate on the standoffs and fix it with the other four M3 × 6 from above. Snug is enough.
#Step 6: Top plate assembly onto the arms
Parts: the main plate assembly with its 4 arms still connected, and the top plate assembly from Steps 4–5.
| Hardware | Per arm | Total (4 arms) |
|---|---|---|
| M3 × 35 socket head | 4 | 16 |
| M3 lock nut | 4 | 16 |
- Seat each arm at its corner of the main plate, matching the position marks from Step 3, with the motors facing up.
- Lower the top plate assembly onto the arms, flight controller arrow pointing forward. Before it closes, feed the ESC cable and the power-module cable up through the main-plate cut-outs.
- Line up the holes. At each corner, push four M3 × 35 down through the top plate, the arm mount and the main plate, and fit a lock nut to each under the main plate.
- Take every screw to finger-tight, then snug each arm's four in a cross pattern. Sight across the frame: all four motors should be level and at the same height.
Tip
Start all sixteen screws before tightening any of them. The top plate will not seat flat if one corner is pulled down first.
#Step 7: Landing legs
Parts: 2 landing legs.
| Hardware | Per leg | Total (2 legs) |
|---|---|---|
| M3 × 30 socket head | 3 | 6 |
| M3 lock nut | 3 | 6 |
- Turn the frame upside down.
- Fit each landing leg at its position on opposite sides of the underside, splayed outward. Fix it with three M3 × 30 and lock nuts, snugged evenly.
- Check that the skids are parallel and at the same height. Then turn the frame over and stand it on its legs.
#Step 8: Optical-flow sensor
Parts: flow-sensor mount, optical-flow sensor and its cable.
Hardware: the mount's own clamp screws and the double-sided tape.
- Slide the flow-sensor mount onto the front ends of the two rail tubes and tighten its clamp screws, so the sensor will have a clear, level view of the ground.
- Stick the sensor to the mount with double-sided tape, lens facing straight down.
- NDAA kit (ARK Flow): point the sensor's connectors toward the rear of the aircraft.
- Standard kit (MTF-01P): note which way the sensor faces. You will set its orientation in Step 10.
- Route the sensor cable up to the flight controller.
#Step 9: Wiring and dressing
| Connection | Flight controller port | NDAA kit | Standard kit |
|---|---|---|---|
| ESC (JST-SH to Dupont cable) | AUX OUT 1–4 | ARK 4IN1 ESC | HGLRC 4-in-1 |
| Power module | Power port | — | — |
| Telemetry radio | Telemetry serial port | RFD 900x-US | LR900-F |
| Optical-flow sensor | NDAA: CAN port. Standard: a spare serial port | ARK Flow, 4-pin JST-GH, DroneCAN | MTF-01P, UART, MAVLink |
| RC receiver | RC input (SBUS) or a spare serial port | Your choice | Your choice |
- Reconnect the ESC to the flight controller with the JST-SH to Dupont cable, on AUX OUT 1–4 as in Step 3, ground wire on the ground (−) row.
- Refit the XT60 power module between the battery and ESC XT90 leads with the included adapters, and plug its cable into the flight controller's power port.
- Plug in the flow-sensor cable for your kit, as in the table.
- Mount the RC receiver away from the ESC. Run its antennas out past the carbon, then plug it into the RC input.
- Tie down every loose wire with cable ties. Keep all leads clear of the props and the motor bells, and check every bullet joint is seated and sleeved.
- Thread the strap through the battery plate slots and strap the battery on. Slide it fore or aft until the centre of gravity sits at the frame centre.