Date: 202005
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 12
Light: Daylight
Aircraft: Small Transport; Low Wing; 2 Recip Eng
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Landing
Airspace: Class D ZZZ
ATC / advisory: Tower ZZZ
Reporter organization: Personal
Reporter function: Pilot Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Commercial
Human factors: Distraction; Situational Awareness; Training / Qualification
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Gear Up Landing; Ground Event / Encounter Ground Strike - Aircraft
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Aircraft Damaged; Flight Crew Took Evasive Action
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: I conducted a VFR flight from ZZZ1 to ZZZ.  Flight conditions were excellent with clear skies; only light winds; and unusually light traffic due to current pandemic flight reductions.  No flight plan was filed; but I remained in contact with ATC throughout the flight.  Upon leaving ZZZ; my route was along the coast; through the 'Route' over ZZZ2 Class B; VOR; then direct to ZZZ.  For the last XX years; I have routinely flown this route each week in my commute from my firm to my residence. I had a passenger; who has flown this route with me for the last year.  As a right-seat regular passenger; she is interested in learning the basics of flying and procedures if the pilot was incapacitated.  She regularly handled the controls during the level-cruise flight and was competent in holding course and altitude.  She could start learning about descent and landings. We began a VFR descent from 8500 ft at 50 miles from ZZZ and notified ATC.  I took over control from the passenger; and explained power reductions; aircraft attitude; descent rate; etc.  At 20 miles out; the airport was visible.  We switched to ZZZ Tower and cleared for a visual straight-in approach to Runway XX.  During the entire process; I explained the techniques for a typical landing; including a power settings 22MP/22RPM (Manifold Pressure/Revolutions Per Minute) and airspeed reduction in order to drop the flaps and gear.  Once 175 kts was reached; the flaps were lowered 10 deg (typical to slow an Aircraft X down to Vgo); which takes several seconds.  During this time; I became distracted while explaining the glideslope; VASI (Visual Approach Slope Indicator) lights; critical aircraft speeds; and the landing checklist. Upon reaching Vgo; I failed to lower the gear.  As Aircraft X settled into the landing at the threshold of Runway XX; the gear warning horn sounded.   I rarely hear the horn and it (unfortunately) sounds similar to the stall warning horn; which is not unusual as you touchdown.  As the aircraft settled; I heard light scraping.  Suddenly; the combination of horn noise; ground speed; and scraping made sense.  I pushed the power forward; I pulled the controls back lightly and the plane responded.  I debated the possibility of dropping the gear; but calculated there was insufficient runway for full gear extension and a complete stop.  Since the plane was responding; I made a small climb; attempting to stay within ground effect and retracted the flaps.  The plane climbed easily and I notified Tower of a go-around.  After establishing a climb; I extended the gear; got '3-green;' turned left cross-wind; toward open fields in the event of an off-field landing.  We could climb; so I turned downwind; close-in.  At 500 ft AGL; I cautiously reduced power to reduce engine stress.  Everything sounded and felt good so I reduced power further; brought the base turn tight and dropped flaps.  The landing was uneventful and I taxied to my tie-down. Following engine shut-down; we exited the aircraft and three ZZZ operations personnel arrived.  I telephoned the Tower and answered several basic questions which lasted 5 minutes or less.  I visually surveyed the aircraft with Operations and they interviewed myself and my passenger.  I produced my pilot information and answered a few questions; which lasted about 10 minutes.  They stated that they had inspected the runway and found no damage--only the remains of the red beacon light from the underside of the aircraft. My damage inspection revealed the following:  -All 6 propeller blade tips were bent backwards.-The engines were able to re-start; but did not sound right.-Both flap skins were severely scraped; almost to the structure.-The aft portion of the underbelly was severely scraped over 2 panelsContributing factors to the failure to extend the gear; resulting in a prop-strike:1.Pilot was distracted during the final approach and did not complete the landing checklist.2.Aircraft X gear warning horn sounds similar to stall warning horn; which both operate at slow aircraft speed.3.The size of the yoke-mounted iPad EFB obstructs the pilot's clear view of the gear landing lights and gear operating switch.4.Straight-in approach vs. full pattern.Significant factors which support pilot proficiency:-Pilot had over X;000 PIC hours of flight experience.-In addition to XXXX PIC hours in make/model; pilot has Y;YYY PIC hours in retractable-gear aircraft.




Synopsis: Pilot flying failed to lower landing gear during landing maneuver.