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7″ Long-Range Quad (6S2P Li-Ion)

A reference long-range build — bigger props and a Li-Ion pack traded for endurance and reach, not punch-outs. This is the same 7″ example that runs through Module 2 (hover power), Module 5 (motor sizing) and Module 6 (flight time) — this page just assembles it into an actual parts list.

Part list

PartChoice (example)Notes
Frame7″ true-X or tank-style, room for a GPS mastLonger arms than a 5″; check prop clearance with 7″ props
Motors4× 2806.5, ~1300 KV, 6SLow KV + big prop trades RPM for efficiency — see Brushless Motors
ESC4-in-1, 40–50 ALong-range hover draw is much gentler than freestyle punch-outs — see ESC
Flight ctrlH7UART count matters here — GPS, telemetry and a digital VTX add up fast — see Flight Controller
Props7″, 2-bladeTwo blades win on peak efficiency at cruise — see Propellers
Battery6S2P Li-Ion (21700 cells), 8.4 AhLi-Ion trades peak current for far more energy per kilogram — see Battery
GPSM10-class moduleMount away from power wiring and the VTX — see GPS Module
ReceiverELRS, long-range packet rateDrop to a lower packet rate (e.g. 50 Hz) for range headroom — see Radio Receiver
Camera/VTX/antennaAnalog or digital, patch + omni diversity on the gogglesSee VTX and VTX Antenna

Target numbers

Continuing the worked example from Module 2 and Module 6:

  • All-up weight goal: ≈ 1.5 kg.
  • Hover power: ≈ 205 W (hover efficiency ≈ 7.3 g/W — right in range for this class).
  • Pack energy: 6S2P, 8.4 Ah × 21.6 V ≈ 181 Wh.
  • Expected flight time: ≈ 42 min hovering, using 80% of the pack — cruise is similar or better, since forward flight is more efficient than hover.

Unlike the 5″ freestyle build, TWR here is not the goal — a long-range quad is sized for endurance, not acceleration. Treat 4–6 as a sensible range rather than chasing the 8–12 a freestyle build wants.

Build order I follow

  1. Solder motors to the 4-in-1 ESC, check rotation directions.
  2. Mount the stack on soft grommets, and mount the GPS on a mast away from power wiring and the VTX — both interfere with the compass and can kill the fix.
  3. First power-up on a current-limited supply (smoke-stopper), props off.
  4. Configure motor directions and calibrate the compass away from any metal desk or tools.
  5. Set the ELRS packet rate for range (e.g. 50 Hz long-range mode), then configure and deliberately test GPS rescue — switch off the radio at altitude over an open field — before trusting it kilometers out.
  6. Maiden close to home first. Only push distance once rescue, failsafe, and the compass have all been proven on real flights.
Props off until the very end

Every first-power-up and configuration step happens with propellers removed. They go on only when you're outside and ready to fly.

Test rescue before you need it

GPS Rescue is not "configured and done" — it's a real failure mode you should trigger on purpose, in the open, before you ever rely on it at range. See GPS Module for the rescue state machine.