Propeller problems

Overview

Props crack, noise or wrong mounting.

Betaflight/INAV, BLHeli32/Bluejay ESC, DJI consumer (closed stack).

Symptoms

Typical "Propeller problems" signs in flight, app or OSD:

• Asymmetric thrust
• Vibration only with certain props
• Prop strike into ground/object
• Motor test without props — all spin evenly.

Common causes

Before replacing parts, rule out software, mechanical and environmental causes:

• Wrong CW/CCW orientation
• Wrong adapter ring
• Old or UV-damaged plastic

Tools needed

Prepare before diagnostics — saves time in the field:

• Prop removal tool
• Multimeter
• Blackbox log reader

Step-by-step fix

Work safely: battery off when working on ESC/motors; props removed; after repair — VLOS test flight.

• Follow CW/CCW diagram.
• After strike — replace ALL props, check motor shaft.
• Do not fly with nick >1 mm.

Additional diagnostics

Motor test without props — all spin evenly.

Blackbox: desync, gyro noise, ESC temperature.

Prop balance — balance or replace in pairs.

When to contact service

If any of the following apply — do not fly and contact authorised service:

• Bent motor shaft or rough bearing — replace motor.
• ESC smells of burnt plastic — do not fly.
• After prop strike — gimbal/IMU error persists.

Prevention

Prevention reduces failure risk and supports EASA Open / VLOS compliance:

• Always carry spare props

Frequently asked questions

Is it safe to fly with "Propeller problems"?

No if the fault affects navigation, power, ESC or link. Fix on the ground first, then conduct a VLOS test flight in open area.

How long does diagnosis take?

Most “Propeller problems” cases — 15–45 min on the ground. Complex ones (firmware, hardware) may need 1–2 h and service.

Must I register repair with the NAA?

No mandatory repair registration, but a maintenance log is recommended for commercial operations.