Large transport aircraft flight crew reported intermittent burning electrical fumes during cruise. A...

Attributes
ACN	1668069
Time
Date	201907
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	Large Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Person 1
Function	Check Pilot Pilot Not Flying Captain
Qualification	Flight Crew Instrument Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument
Events
Anomaly	Aircraft Equipment Problem Less Severe Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

During climb to FL380 started getting fumes of unknown origin in cockpit; smelled like something electrical burning or overheating. Asked the captain if he smelled something; which he did. While investigating instruments and lights for 2-3 minutes; [the] smell started to dissipate. We started discussing possible causes and plan of action. Closest airports were ZZZ1; ZZZ2; and ZZZ. Got weather for ZZZ2 and ZZZ. After level off at FL380; the smell started to come back. Once the smell came back; [we] swapped roles and [requested priority handling]; requesting a divert to ZZZ due to familiarity and less traffic congestion. While I talked to ATC and started flying forward ZZZ; pm (pilot monitoring) started setting us up for ZZZ. After setting up approach notified [operations control]. Landed in ZZZ uneventfully; taxied off runway and got inspected by fire crews which didn't see anything on thermal scan. Taxied to ramp to have maintenance check the aircraft.

Original NASA ASRS Text

Title: Large Transport aircraft flight crew reported intermittent burning electrical fumes during cruise. After troubleshooting the problem; the flight crew decided to divert.

Narrative: During climb to FL380 started getting fumes of unknown origin in cockpit; smelled like something electrical burning or overheating. Asked the Captain if he smelled something; which he did. While investigating instruments and lights for 2-3 minutes; [the] smell started to dissipate. We started discussing possible causes and plan of action. Closest airports were ZZZ1; ZZZ2; and ZZZ. Got weather for ZZZ2 and ZZZ. After level off at FL380; the smell started to come back. Once the smell came back; [we] swapped roles and [requested priority handling]; requesting a divert to ZZZ due to familiarity and less traffic congestion. While I talked to ATC and started flying forward ZZZ; PM (Pilot Monitoring) started setting us up for ZZZ. After setting up approach notified [Operations Control]. Landed in ZZZ uneventfully; taxied off runway and got inspected by fire crews which didn't see anything on thermal scan. Taxied to ramp to have Maintenance check the aircraft.

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.

Large transport aircraft flight crew reported intermittent burning electrical fumes during cruise. After troubleshooting the problem; the flight crew decided to divert.