Skyhawk 172/Cutlass 172
Flight Crew Commercial; Flight Crew Flight Instructor
Flight Crew Last 90 Days 53; Flight Crew Total 4391; Flight Crew Type 67
Distraction; Situational Awareness
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Gear Up Landing; Ground Excursion Runway
General None Reported / Taken
Human Factors
I was conducting a training flight on Airman Certification Standards (ACS) maneuvers to prepare a student for the practical test to be taken within 4 days.  Initially; we conducted normal; short field; and soft field takeoffs and landings without incident.  Then; we departed to the practice area and practiced unusual attitude recoveries; steep turns; slow flight; approach stalls; and departure stalls from 3;000 feet MSL.  That complete; I directed the student to return to the home airport.  On downwind entry; we were 500 feet above pattern altitude.  I considered this a good opportunity to give my student a simulated engine failure and have him continue to the runway.  On downwind; we were at an altitude lower than the student felt comfortable.  He stated that he didn't feel we could make it.  However; to demonstrate that the landing could still be made if the conditions (engine out) were real; I took the controls made a short approach (a banked continuous base to final turn) and lined the aircraft up with the runway in a landing attitude. Unfortunately; during the maneuver I became obsessed with monitoring our airspeed for proper glide speed and maneuvering during the turn at the neglect of ensuring the landing gear was extended.  We landed with the gear retracted. The flare (round out) was at normal altitude and attitude. Overall; it was not a bad landing.  The student caught the error prior to me when we heard scraping.  The aircraft slid and eventually slid off the runway to a point between the runway and taxiway.One human performance consideration may have been a factor.  I have been conducting training in both straight gear and retractable gear C-172s switching between the two on the same day.  That was the case on this day.  I had flown 0.7 [hours] practicing landings with one student in a fixed gear 172 in the morning; driven to a different airport; and flew in this student's retractable 172 in the afternoon. My mindset was fixated on making the landing and not on the differences between the two aircraft.
Flight Instructor reported a gear-up landing occurred during a training flight. Instructor stated they had flown a fixed gear aircraft earlier and had not focused on the differences with flying a retractable gear aircraft.