Unexpected ATTI mode

Overview

Aircraft switches to ATTI without GPS — drifts in wind.

DJI Fly/Pilot, DJI Assistant 2, Betaflight, INAV, ArduPilot.

Symptoms

Typical "Unexpected ATTI mode" signs in flight, app or OSD:

• ATTI indicator yellow
• No position hold
• Wind pushes aircraft
• Log firmware versions: aircraft, RC, app.

Common causes

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

• GPS lost temporarily
• Compass interference
• Flying under bridges / near metal

Tools needed

Prepare before diagnostics — saves time in the field:

• Data USB
• Full battery
• Backup config (BF .bbl / DJI log)

Step-by-step fix

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

• Take manual control; land if needed.
• Fly open area; regain GPS lock.
• Avoid flying under bridges in GPS mode.

Additional diagnostics

Log firmware versions: aircraft, RC, app.

ATTI mode — GPS vs sensor health.

Vision cal — in well-lit room.

When to contact service

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

• Firmware update stuck >30 min — DJI support with logs.
• Aircraft not recognised by PC — recovery mode.
• Vision sensor error after cleaning — service.

Prevention

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

• Wind margin
• ATTI training

Frequently asked questions

Is it safe to fly with "Unexpected ATTI mode"?

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 “Unexpected ATTI mode” 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.