B767 check airman reported getting a main cargo door warning during cruise; resulting in an air turn...

Attributes
ACN	1717169
Time
Date	202001
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	VFR
Component
Aircraft Component	Door Warning System
Person 1
Function	Check Pilot Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine Flight Crew Instrument
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy

Narrative:

At FL390 we got main cargo door warning; pressurization was normal; we followed QRH checklist; we advised ATC and descended to 10;000 feet; notified the company and returned to ZZZ. Approach and landing was uneventful.

Original NASA ASRS Text

Title: B767 Check Airman reported getting a Main Cargo Door warning during cruise; resulting in an air turnback.

Narrative: At FL390 we got Main Cargo Door warning; pressurization was normal; we followed QRH checklist; we advised ATC and descended to 10;000 feet; notified the company and returned to ZZZ. approach and landing was uneventful.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

B767 check airman reported getting a main cargo door warning during cruise; resulting in an air turnback.