Date: 201405
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Skyhawk 172/Cutlass 172
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Training
Flight phase: Takeoff / Launch
ATC / advisory: CTAF ZZZ; FSS ZZZ
Second aircraft: Chancellor 414A / C414
Aircraft component: VHF
Component problem: Improperly Operated
Reporter organization: Personal
Reporter function: Instructor; Pilot Not Flying
Reporter qualification: Flight Crew Commercial; Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Multiengine
Human factors: Communication Breakdown
Anomaly: Conflict Ground Conflict; Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Became Reoriented; Flight Crew Rejected Takeoff
Contributing factors: Human Factors; Procedure
Primary problem: Human Factors

Narrative: A training cross country flight was scheduled for the morning. After preflighting the airplane and going over the flight plan with the student; we boarded and turned the airplane on. Before taxiing we received the weather on the CTAF on radio Number 2 (we have the three clicks on the mic system to pick up the weather). The student announced that we would be taxiing from our location to Runway 28 (winds were calm so we choose 28 because it is the one that is favored by local traffic and is closer to our starting location). After our taxi we did a normal before takeoff check; briefed our departure; called FSS to activate our flight plan; and then set up our radios for the flight (after takeoff we were going to pick up flight following with Center). The radios were reset and the local CTAF frequency was changed to radio Number 1 and Center was on standby on radio Number 1. On radio Number 2 the student put in the AWOS and CTAF for our first stop on the cross country. After that was done we pulled up to the hold short line; checked for traffic (during the time from engine start to taxi and run up; we did not hear any other traffic in the area). The student announced our departure on the CTAF and we took the runway. As we were picking up speed but still on the runway I noticed a couple of lights at the end; once I realized that the lights had propellers over them; I hit the brakes and called for an aborted takeoff. The student cut the power and a few seconds later a twin (looked like a 414) came over the top of us departing from Runway 10. Now stopped on the runway we checked that everyone and the airplane was ok; (at this point I realized that the frequency we were talking on was 122.75 which is incorrect the correct frequency was 122.725. I corrected the frequency. We took off and completed the flight with no further incident. We did do a check of both our radios and they both function normally. A couple of things stand out from this incident:1. I would encourage a student/pilot not to change radios at the last minute before takeoff; and if it is required a radio check would be a good procedure to ensure that the radio is working properly and on the right frequency;2. We were on the correct frequency for a good amount of time 10-15 minutes; it seems obvious to me that the other aircraft did not report on the CTAF at any point during their taxi and maybe departure. I may even speculate that they were not listening to the CTAF as they could have heard us taxiing to the opposite runway and could have given us a heads up on their intentions. The airport is pretty much empty during the early morning and that may encourage pilots to not report their positions or not listen because 'there is no one else out here'3. The fact that the other aircraft had its lights attracted my attention to it and was the only reason I stared at it long enough to see it was an airplane. Would highly recommend everyone have there lights during critical times of flight.




Synopsis: C172 instructor reports a near collision with a C414 taking off in the opposite direction. The reporter rejects and the C414 pilot continues his takeoff. The radio was found set to the wrong CTAF setting by one click; but was thought to have been mis-set just prior to takeoff. No calls were ever heard from the C414 pilot.