Sub250 Whoopfly16 HDZero

The build centers on an inverted-pusher layout with a one-piece injection-molded duct frame — rigid, crash-resistant, and notably more durable than flexier Meteor75-style frames — with foam bumpers included for the ducts. Electronics are a Redfox A1 F4 5A AIO with built-in SPI ELRS, feeding an HDZero Whoop Lite VTX (switchable 25/200mW) and Nano Lite camera for native 720p60 low-latency digital video on HDZero goggles such as the BoxPro+.

In the air it flies like a trainer should: the stock PID tune is smooth and locked-in out of the box, handling both angle and acro flying without retuning — forgiving for beginners and consistent for reflex practice. The 1002 21000KV motors deliver strong, punchy power for the 75mm 1S class, with reserve for outdoor cruising.

It sits at the heavier end of the 75mm 1S class — heavier than competitors like the BetaFPV Meteor75 — which costs some efficiency and makes it a locked-in trainer rather than a racing or freestyle machine. Real-world flight time runs around 3 minutes indoors on the 530mAh pack, versus the manufacturer's 4.5-minute claim.

Spares are a strong point: Sub250 sells frames, Gemfan 1608-3 props, 1002 motors, the Redfox A1 AIO FC, and A30 530mAh packs individually, and the A30 battery connector is BT2.0-compatible, so common 1S HV whoop packs and chargers work. One platform caveat: the ELRS receiver is SPI, not UART — it binds to any ELRS 2.4GHz radio through Betaflight, but its firmware is baked into Betaflight and must stay version-matched with your radio's ELRS major version.