Skyhawk 172/Cutlass 172
Flight Crew Flight Instructor; Flight Crew Commercial; Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 220; Flight Crew Total 3300; Flight Crew Type 1500
Communication Breakdown; Distraction; Training / Qualification
Conflict NMAC
Flight Crew Took Evasive Action
Human Factors; Environment - Non Weather Related
During a practice GPS 21 approach into EYE without ATC advisories; my student and I were on the outbound leg of the hold for the approach. We were monitoring the CTAF frequency for EYE and were at 3;000 MSL and preparing to descend on the approach when my student saw another aircraft pass directly underneath us around 2;900-2;800 MSL. Shortly after they passed beneath us I lost visual contact with them. The aircraft was on the ground at EYE and told us they had seen us and dived in order to miss us as they were also on the GPS 21 approach; but were on a frequency for a nearby airport. The pilot of the other aircraft did not say he saw us until they were almost on top of us.While the other pilot and I were both following recommended VFR scanning procedures; the incident might have been avoided by getting radar advisories from IND Approach; so that they could have provided separation services for the approach.
Two training flights; a C172 and a PA28 suffered an NMAC while maneuvering on the course reversal for the same practice GPS at a non-towered airport. The C172 was utilizing the correct CTAF frequency; but the PA28 was utilizing an incorrect frequency for a different airport.