PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Flight Crew Commercial; Flight Crew Flight Instructor; Flight Crew Instrument
Flight Crew Last 90 Days 60; Flight Crew Total 380; Flight Crew Type 25
Communication Breakdown; Situational Awareness
Conflict NMAC; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Took Evasive Action
Human Factors; Procedure
I was doing pattern work with my student. Once we turned crosswind; we noticed an aircraft pass underneath us approximately 50 ft. Aircraft Y made no radio calls and did not enter the pattern on a 45-degree entry. I took controls from the student and made the decision to go right over the lake to avoid further conflict. I made a call asking if there was 'anyone else on midfield left downwind Runway XX.' They did not respond. I made the decision to leave the pattern to the south after I noticed my aircraft was faster and going to overtake Aircraft Y. After I announced that I was leaving the pattern; the aircraft in question made a call that he was turning left base Runway XX. Shortly after Tower opened XA:00 and the aircraft departed the pattern to the north. Aircraft had capability to make the calls and chose not to; leading to a potential midair collision.
PA-28 Flight Instructor reported taking evasive action to avoid an uncommunicative aircraft as well as a potential midair collision while entering the pattern.