B737 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 182; Flight Crew Type 1550
Time Pressure; Distraction
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
Flight Crew Returned To Departure Airport; Flight Crew Landed As Precaution; Flight Crew Became Reoriented
Human Factors; Aircraft
We had an unscheduled aircraft swap with a 23 minute turn. I went onto the next aircraft to get it ready; the Captain stayed with our inbound aircraft to shut it down. As it was such a quick turn; I was a bit rushed; Flight Attendant was talking to me while I was setting up cockpit so a little distracted as well. We boarded quickly and taxied out. Taxi out was normal and we noticed no abnormal indications or flags. Once airborne; inop flags then dropped on heading and attitude indicator. Attitude indicator and heading indicator were not moving normally so I informed the Captain I couldn't fly the RNAV Departure and we needed a vector. The Captain requested a vector from departure. We assessed that the DG and attitude indicators were not moving and we decided to return to the airport. We returned to the departure airport and landed visually. After returning to the gate; we realized the IRS's were never turned on. This was missed during the preflight.I shouldn't have allowed distractions or time issues to interfere with procedures and flows i.e.: turning on the IRS. Although we did not have any flags on the instruments taxiing out; I incorrectly interpreted the thru flight versus originating flow; this would have caught the error as the GPWS wouldn't have tested. Also; when checking recall on the checklist; I poked the button quickly and didn't see a light. I will take the time to verify its status.
B737 First Officer reported being distracted during cockpit set up for a quick turn and forgot to turn on the IRS. No flags were visible during taxi out; but once airborne it became obvious that heading and attitude displays were frozen. The flight returned visually to the departure airport.