B737-700
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 200
Situational Awareness
Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew Returned To Departure Airport; General Maintenance Action
Aircraft
During our takeoff roll both the Captain and I noticed an unusual smell. Shortly after we rotated the smell intensified quickly. At roughly 800 feet AGL the FAs called the cockpit to report the same smell in the back of the aircraft. They stated it was intensifying quickly. Both the Captain and I agreed the smell was of burning engine oil and we quickly donned the O2 masks. We stopped the climb and [requested priority handling] with ATC. The Captain began running the Smoke/Fumes Checklist; but we both agreed it was not proper for the event we were experiencing and we didn't have the time to complete the necessary steps and prepare for landing.We focused our attention on safely and quickly returning to the ground as we were concerned for the safety of our cabin crew and passengers. The Captain quickly briefed our passengers that we were aware of the smell and were returning to the field. We ran our necessary checklists; retrieved our landing data and landed. We stopped on the runway and allowed CFR (Crash Fire Rescue) to inspect the aircraft for any noticeable issues outside the aircraft. They cleared us of any obvious external issues and we returned to the gate.We were informed that the aircraft had an engine wash the night before. Maybe doing a high power run prior to returning the aircraft to service; while operating the packs to verify the system is clear of any contaminates that may have been dislodged or blown into the bleed valves/system.
B737-700 First Officer reported unusual odor during takeoff roll which intensified during initial climb. Flight executed a return to departure airport.