PA28 PLT ON R BASE FOR RWY 26 AT GFK CONFLICTED WITH TFC DEP FROM RWY 35R; EXECUTES TURN AND CONFLICTS WITH ANOTHER ACFT.

Narrative

MY STUDENT (PVT PLT WORKING TOWARDS COMMERCIAL) AND I WERE APCHING GFK FOR A FULL STOP LNDG. WHEN WE WERE ABOUT 1 - 1 1/2 MI NE OF THE ARPT; TWR TOLD US TO ENTER A R BASE FOR RWY 26 (ATIS DID NOT INCLUDE THIS AS BEING AN ACTIVE RWY FOR TKOFS AND LNDGS; BUT OTHER ACFT WERE USING IT; AND FREQUENT RWY CHANGES HAVE BEEN COMMON LATELY AS WORK IS BEING DONE ON RWY 35L). WHILE ON FINAL FOR RWY 26; A PA28 TOOK OFF ON RWY 35R (ESTIMATED MISS DISTANCE 1000 FT HORIZ AND 250 FT VERT). MY STUDENT AND I IMMEDIATELY STARTED A CLBING R TURN TO AVOID THE TFC; AND A NEW VOICE ON THE TWR FREQ INSTRUCTED THE ACFT OFF OF RWY 35R TO DO THE SAME. WHILE DOING THIS; WE PASSED CLOSE UNDER ANOTHER ACFT THAT WAS POSSIBLY ON THE DOWNWIND FOR RWY 26 (ESTIMATED MISS DISTANCE OF 500 FT VERT). THE TWR DID NOT SEEM TO HAVE A GOOD IDEA ABOUT WHERE ALL THE ACFT IN THE PATTERN WERE; OR HOW THEY WERE GOING TO LAUNCH ALL OF THE ACFT HOLDING SHORT OF 3 DIFFERENT RWYS. ON THE GND THERE WERE ABOUT 10 ACFT COMBINED HOLDING SHORT OF RWY 35R; RWY 17L AND RWY 26. IT IS COMMON FOR THE TWR TO USE RWY 26 FOR STOP-AND-GO AS WELL AS DEPARTING TFC WHILE USING RWY 35R FOR FULL STOPS; OR USE RWY 35R FOR STOP-AND-GO; FULL STOP AND DEPARTING TFC AND RWY 26 FOR DEPARTING TFC ONLY. I AM NOT SURE WHY THEY WERE USING THIS CURRENT CONFIGN. SOME OF THE FACTORS THAT CONTRIBUTED TO THIS WERE THE FACT I RECEIVED A STANDARD WX BRIEFING EARLIER THAT DAY; AND MY STUDENT GOT ONE IMMEDIATELY BEFORE OUR FLT AND THERE WERE NO NOTAMS FOR THE GFK ARPT OTHER THAN APCH CTL BEING CLOSED IN THE LATE EVENING. UPON RETURN; I RECHKED THE NOTAMS AND RWY 35L/17R WAS NOTAM'ED CLOSED LESS THAN 15 MINS BEFORE OUR ARR WITH NO INFO OF THIS ON ATIS; OR FROM APCH CTL AND TWR. GFK IS IN DESPERATE NEED OF ANOTHER RWY TO PARALLEL RWY 8/26. THERE IS AN EXPONENTIALLY INCREASING AMOUNT OF STUDENT TRAINING HAPPENING AT THIS ARPT; AND HAVING THE MAIN RWY (RWY 35L/17R) CLOSED DURING THE MIDDLE OF THE DAY (WITH WINDS OUT OF THE N AT ABOUT 8 KTS) CAUSES PROBS TOO NUMEROUS TO MENTION. THE APCH END OF RWY 26 AND DEP END OF RWY 35R ARE VERY CLOSE; AND ATTEMPTING TO LAND ACFT ON RWY 26 AND TAKE OFF ON RWY 35R IS A SERIOUS SAFETY CONCERN. LUCKILY MY STUDENT AND I RECOGNIZED THE SIT AND POTENTIAL CONFLICT AND TOOK EVASIVE ACTION BEFORE THE SIT GOT OUT OF CTL.