PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Flight Instructor; Flight Crew Commercial
Flight Crew Last 90 Days 334; Flight Crew Total 673; Flight Crew Type 500
Situational Awareness
Conflict NMAC
Flight Crew Took Evasive Action
Human Factors
When on downwind at Y14; [I] made a call when midfield at 1000 AGL. [A second aircraft] made a '10 miles to the west; landing runway 16 Lincoln County' call. [We] made [our] landing and proceeded to takeoff for more pattern work. When approaching downwind for runway 16 [we] made another downwind call to Y14. Upon turning base to final; I noticed a shadow of an airplane coming directly at us. I took evasive action to get out of the area to avoid a mid-air collision. When finally getting visual contact with [the other aircraft] there was 100 ft vertical separation between our two airplanes. While no radio calls are required at Y14; [the other aircraft] did take advantage of 91.113 and endangered the lives of other pilots and pedestrians on the ground.
PA28 instructor pilot reported experiencing a NMAC in the pattern at Y14.