Date: 201906
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Light: Daylight
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
Airspace: Class B ZZZ
ATC / advisory: Tower ZZZ
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Situational Awareness
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Flight Deck / Cabin / Aircraft Event Illness / Injury
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport
Contributing factors: Aircraft; Procedure; Human Factors; Company Policy
Primary problem: Human Factors

Narrative: The First Officer was the Pilot flying on this leg.  We were in ZZZ on an originator. Runway XXR was the active runway.  During takeoff at approximately 90 knots the First Officer and I both started to smell a faint odor in the cockpit.  We briefly discussed it as it continued to intensify and I made the decision to continue takeoff.  As we passed through 500 feet AGL; the odor turned into heavy burning oil-like fumes.  I could noticeably feel tingling in my fingers and a slight light-headedness.  We both went on oxygen.  At approximately 800 feet AGL; the flight attendants called and reported significant fumes throughout the cabin.  I notified ATC; [advised]; and requested vectors for a return to Runway XX. We stopped the climb and while the First Officer flew the aircraft; I ran the Smoke; Fire; or Fumes Checklist using the QRC.  After completing that; the QRC directed us to the QRH; Smoke; Fire or Fumes Checklist.  The QRH checklist seemed designed for electrical fire/fumes; as it called for shutting down multiple electrical components. The First Officer and I agreed that what we currently had was not an electrical problem and decided to stop that checklist and prepare for the return.  We gathered landing data via [weight and balance system] and completed the Descent and Approach Checklists as well as quickly referencing the Diversion Checklist.  The First Officer flew the aircraft and prepared the FMC and cockpit for a landing on Runway XX at ZZZ. When I talked to the flight attendants a second time they reported the fumes were still very strong and I could hear them coughing while trying to talk.  We focused on getting the aircraft on the ground as quickly and as safely as possible.  I briefed the passengers on the PA and told them we would be returning to ZZZ.  When we were established on final approach; I took the aircraft from the First Officer and we made a normal landing (we were under max gross weight for landing).  We stopped on the runway to allow the Fire/Crash Crews to inspect the exterior of the aircraft.  They did not see anything out of the ordinary and we asked them to follow us to the gate.We pulled into the gate and had the passengers exit normally using the jet bridge.  The First Officer and I were on oxygen from 500 feet AGL after takeoff until engine shutdown at the gate.  After all passengers had deplaned; I debriefed with the crew.  All five of us reported symptoms that included headaches; numbness in fingers; soreness in throat/chest; shortness of breath; dry cough and light-headedness.  We went to a local emergency room and were released five hours later after continuous oxygen treatment and carbon monoxide blood tests.After the flight; Maintenance told us they had performed an engine wash the night before the incident and that it is possible that it had something to do with the fumes.  If that is the case; then perhaps the engine wash and subsequent engine run procedures need to be reviewed in an effort to prevent this type of event from happening again.




Synopsis: Flight crew flying 737-700 encountered fumes in the cockpit after takeoff.