Heavy transport aircraft captain reported 'dirty socks odor mixed with oily smell' during flight.

Attributes
ACN	1698225
Time
Date	201911
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	Heavy Transport
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Air Conditioning and Pressurization Pack
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Events
Anomaly	Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

Fume event. Intermittent air system odor inflight w/pack 1 meled inoperative & packs 2 & 3 on. Pack outlet temps were the following: #2=33F; #3=133F. Cockpit trim air valve temp=110F. Odor not noticeable when pack #2 temp was below 0 degrees F and cockpit trim air valve below 70 F. Odor was that of dirty socks mixed with an oily smell.cause: possible air conditioning system contamination from engine bleed air.suggestions: more frequent maintenance of the air conditioning system.

Original NASA ASRS Text

Title: Heavy Transport aircraft Captain reported 'dirty socks odor mixed with oily smell' during flight.

Narrative: Fume event. intermittent air system odor inflight w/pack 1 MELed INOP & packs 2 & 3 on. Pack outlet temps were the following: #2=33F; #3=133F. Cockpit trim air valve temp=110F. Odor not noticeable when pack #2 temp was below 0 degrees F and cockpit trim air valve below 70 F. Odor was that of dirty socks mixed with an oily smell.Cause: possible air conditioning system contamination from engine bleed air.Suggestions: more frequent maintenance of the air conditioning system.

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.