Smashing SiFly’s time: how one team built the most efficient drone ever made

It is a truth universally acknowledged that breaking an official Guinness world record is never easy. But South African, Luke Maximo Bell and his dedicated team have done just that, obliterating the record for the longest electric drone flight by keeping their craft airborne for 4 hours, 21 minutes and 39 seconds.

The previous official record for the longest flight of an electric multirotor belonged to SiFly Aviation. On 26 July 2025, in Chualar, California, their Q12 drone – an all-electric vertical takeoff and landing (VTOL) craft – flew for exactly 3 hours, 11 minutes and 54 seconds on a single battery charge.

Not content to rest on their laurels after unofficially beating that old record by 20 minutes with an earlier model, Maximo’s team set out to upgrade everything to make their new record official. A huge, hearty congratulations is in order for Maximo and his entire crew for this magnificent achievement!

Building the most efficient drone ever made required some truly ingenious engineering. The team redesigned the motor mounts to a single-piece C-clamp style, which saved a crucial 26g overall. After a rather disappointing issue with the propellers digging into the ground on early test flights, 3D-printed landing legs featuring flexible TPU joints that simply absorb the impact of a crash without snapping.They powered the whole operation was a colossal SMC semi-solid state battery boasting an incredible 380 watt-hours per kilogram, weighing in at about 5kg.

But lightweight parts and raw power are nothing without a brilliant brain. This is where the flight controller played an essential role. By employing the CubePilot Cube, and RTK GPS setup the team secured immediate access to 31 GPS satellites and completely eradicated the vibration and clipping issues that had plagued their earlier attempts. Once they figured out that the controller inverts the pitch axis by default, they achieved a beautifully solid flight.

‘The drone is so stable now,’ Maximo remarked, noting it was almost on the level of a DJI for position hold.

The Cube’s reliability is truly legendary: as you confirmed, the exact same flight controller is used in the Kraus Hamdani Aerospace K1000ULE (also referred to as the K1000e). That quiet, solar-electric fixed-wing drone holds a world record of its own, having flown for 75 hours and 53 minutes non-stop. This makes it the longest-endurance uncrewed aircraft system (UAS) in its weight class, earning a $270m military contract for its unique capabilities. ( The company has a South African living in America at the helm…)

Maximo’s record-breaking flight was a triumph of strategy. Armed with a laptop and a Wi-Fi connection, he adjusted the drone’s ArduPilot settings mid-flight, smoothing out the craft’s stability with a tweak of a notch filter. By testing different speeds around an autonomous racetrack using an RTK antenna for centimetre-level positioning accuracy, the team discovered that flying forward at a leisurely 5.5 metres per second (12mph) actually consumed significantly less power than hovering. On the straights, it averaged about 500W, but surprisingly pulled only 450W during turns, prompting them to adapt to a shorter, curvier track to increase overall efficiency.

By the time the magical four-hour mark ticked by, they still had 8% battery capacity remaining. Maximo nervously brought the drone to a hover just in front of the landing area, squeezing every last drop out of the extremely low 0.2 C rate battery until it was completely flat.

It takes a monumental amount of patience, testing and brilliant 3D-printing to pull off something like this. Bravo to Maximo and his team.