Instrument instructor with student descends below published altitude in ILS approach.

Attributes
ACN	256009
Time
Date	199311
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : gvt
State Reference	TX
Altitude	msl bound lower : 1100 msl bound upper : 2100
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : gvt
Operator	general aviation : instructional
Make Model Name	Small Aircraft, Low Wing, 2 Eng, Retractable Gear
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	Other
Function	instruction : instructor
Qualification	pilot : cfi pilot : commercial
Experience	flight time last 90 days : 95 flight time total : 2150 flight time type : 1100
ASRS Report	256009
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : student
Events
Anomaly	altitude deviation : crossing restriction not met non adherence : published procedure non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

This was an instrument training flight in a light twin engine airplane with a pilot with very limited instrument time, particularly IMC. The student also has limited experience in complex aircraft. We were performing the NDB runway 17 approach into greenville, tx. Upon turning procedure turn inbound, the student initiated a descent to the MDA of 1060, although the procedure calls for the descent after crossing the NDB. We had not yet crossed the beacon, and were approximately 3 mi north of the NDB when the descent was begun. The minimum altitude for the segment we were on is 2100. The aircraft descended to an altitude of 1100 ft before CFI took control and climbed back to the appropriate altitude. I believe the factors leading to the problem are easy to avoid. Before low-time pilots fly in IMC, particularly in aircraft 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 instrument instruction, making sure the airplane is kept under control, communication with ATC, and monitor the navigation 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 problem with aircraft control. The descent rate became excessive and the airplane reached an altitude 1000 ft below the minimum altitude for that part of the approach. ATC made a query as to the problem with the altitude and CFI immediately initiated a climb to the appropriate altitude. The problem was a case of the CFI's attention 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.

Original NASA ASRS Text

Title: 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.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.