INST INSTRUCTOR WITH STUDENT DSNDS BELOW PUBLISHED ALT IN ILS APCH.

Narrative

THIS WAS AN INST TRAINING FLT IN A LIGHT TWIN ENG AIRPLANE WITH A PLT WITH VERY LIMITED INST TIME; PARTICULARLY IMC. THE STUDENT ALSO HAS LIMITED EXPERIENCE IN COMPLEX ACFT. WE WERE PERFORMING THE NDB RWY 17 APCH INTO GREENVILLE; TX. UPON TURNING PROC TURN INBOUND; THE STUDENT INITIATED A DSCNT TO THE MDA OF 1060; ALTHOUGH THE PROC CALLS FOR THE DSCNT AFTER XING THE NDB. WE HAD NOT YET CROSSED THE BEACON; AND WERE APPROX 3 MI N OF THE NDB WHEN THE DSCNT WAS BEGUN. THE MINIMUM ALT FOR THE SEGMENT WE WERE ON IS 2100. THE ACFT DSNDED TO AN ALT OF 1100 FT BEFORE CFI TOOK CTL AND CLBED BACK TO THE APPROPRIATE ALT. I BELIEVE THE FACTORS LEADING TO THE PROB ARE EASY TO AVOID. BEFORE LOW-TIME PLTS FLY IN IMC; PARTICULARLY IN ACFT WHICH THEY HAVE LIMITED SKILL/EXPERIENCE; THE CFI SHOULD ASCERTAIN THAT THE STUDENT IS CAPABLE OF HANDLING THE WORKLOAD INVOLVED. NOT ONLY DOES THE STUDENT HAVE AN INCREASED WORKLOAD; BUT THE WORKLOAD FOR THE CFI IS TREMENDOUSLY GREATER. GIVING INST INSTRUCTION; MAKING SURE THE AIRPLANE IS KEPT UNDER CTL; COM WITH ATC; AND MONITOR THE NAV OF THE AIRPLANE ALL AT THE SAME TIME CAN BE VERY DIFFICULT. IN THIS CASE; THE CFI WAS INSTRUCTING THE STUDENT IN NDB INTERCEPTS AND TRACKING; AND HELPING THE STUDENT FLY THE AIRPLANE. THE STUDENT WAS HAVING A PROB WITH ACFT CTL. THE DSCNT RATE BECAME EXCESSIVE AND THE AIRPLANE REACHED AN ALT 1000 FT BELOW THE MINIMUM ALT FOR THAT PART OF THE APCH. ATC MADE A QUERY AS TO THE PROB WITH THE ALT AND CFI IMMEDIATELY INITIATED A CLB TO THE APPROPRIATE ALT. THE PROB WAS A CASE OF THE CFI'S ATTN BEING DIVIDED INTO SO MANY DIFFERENT AREAS; THAT A CASE OF OVERLOAD WAS REACHED. CFI'S SHOULD BE VERY CAUTIOUS THAT THEY NOT ONLY BE CAREFUL NOT TO OVERLOAD THEIR STUDENTS; BUT MORE IMPORTANTLY; BE CAREFUL NOT TO BECOME OVERLOADED THEMSELVES.