Cessna 152
Flight Crew Multiengine; Flight Crew Commercial; Flight Crew Flight Instructor; Flight Crew Instrument
Flight Crew Last 90 Days 223.5; Flight Crew Total 914; Flight Crew Type 880.7
Conflict NMAC
General None Reported / Taken
Procedure; Human Factors
My student and I were flying in the left hand traffic pattern for Runway 24 at KABE.   On one landing approach; I heard another aircraft be cleared for the RNAV 31 practice approach; restricted to 1;000 feet (MSL) or above.  I heard the pilot acknowledge and state to tower that he would climb on runway heading to 3;000 feet (MSL); after going missed approach.  Please note that Runway 31 is closed for construction. After our touch-and-go; my student continued in the left traffic pattern; climbing to pattern altitude of 1;400 feet MSL (1;000 AGL).  I was monitoring my student; and looking for traffic on approach to Runway 24.  Our downwind leg was approximately 2/3 of a mile south of Runway 24 and parallel.  That put our position less than 1/4 mile from the approach end of Runway 31.  At approximately midfield in the left downwind; my student (a Russian national) began screaming unintelligibly and gesticulating.  In trying to determine what he was yelling about; I looked at him and saw an aircraft slightly above our altitude and in our 8 o'clock position flying directly away from us.  We had not made any evasive actions. Upon landing; I spoke with another instructor who had witnessed the incident from the ground; and thought the aircraft passed within 20 feet of each other.  The other instructor also indicated that the other aircraft had banked to avoid our aircraft.  I contacted ATC to obtain the aircraft's tail number for this report. The flight school I work for is located at KABE. I am familiar with most of the training aircraft by tail number from both; our school and the local flying club; as well as the flight school at neighboring KXLL.  The tail number was unfamiliar to me; and likely visiting for practice instrument approach training.  I have made a number of practice approaches to every runway at KABE; both as student and instructor.  When Runway 13-31 closed for construction; only RNAV approaches became available for those runways.  Thus; low approaches became the norm; even during times of significant flight operations out of the passenger terminal; the private hangars; and the general aviation hangars.  I firmly believe that a practice instrument approach in VMC with an altitude restriction should also clarify when the climb should be initiated on the miss.  Leaving it to pilot discretion may have allowed the pilot of that aircraft to climb through the occupied traffic pattern.
As I was receiving the briefing for the position I was told of the current traffic. Aircraft Y was cleared for an altitude restricted low approach to Runway 31 due to the runway being closed and Aircraft X was on the left downwind to Runway 24. I looked out the window and observed the traffic at the time they were just about to pass and considered them separated but not the plan I would have chosen if I were on the position. I assumed that traffic had been called since it was too late at that point. If both aircraft had known the plan; that Aircraft Y would pass underneath Aircraft X on the downwind; then they would have been more aware of what was going on.
Instructor pilot in a light single and the Local Controller reported an NMAC in the pattern at ABE airport. The pilot feels it was a much closer call than the controller thought it was.