GA small aircraft on a training flight descended below FAF altitude too soon.

Attributes
ACN	123191
Time
Date	198909
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : elm
State Reference	NY
Altitude	msl bound lower : 3000 msl bound upper : 3300
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : elm tower : mli
Operator	general aviation : instructional
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other descent : approach
Flight Plan	IFR
Person 1
Affiliation	Other
Function	instruction : instructor
Qualification	pilot : commercial pilot : instrument pilot : cfi
Experience	flight time last 90 days : 105 flight time total : 1100 flight time type : 28
ASRS Report	123199
Person 2
Affiliation	Other
Function	instruction : trainee
Qualification	pilot : private
Events
Anomaly	altitude deviation : crossing restriction not met altitude deviation : excursion from assigned altitude non adherence : published procedure non adherence : clearance
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During IMC/IFR condition on an ILS 24 approach into elmira airport in ny, we were intercepting the localizer to the ILS 24. I had never flown with the student before, but I thought that the student was familiar with his own flying club's airplane. The student was doing the radio work. We checked the frequencys and identifiers for the ILS approach and the ADF outer marker. The only thing that I forgot was to check the ADF needle for the correct indication. The clearance was: maintain 3300 until alpine, cleared for the ILS approach 24. On the localizer inbound for the outer marker and suddenly the glide slope moved in but just a little. The student then told me that we were over alpine. I looked at the ADF needle, and it showed 'dead' 180 degrees, so I let him continue (which I later learned was a mistake). We descended to between 3000' and 3100' before I understood that something was wrong. Before either of us had a chance to apply power to level off, ATC called 'low altitude alert. Check altimeter setting. Maintain 3300' until alpine.' I applied full power and climbed to 3200' and then the glide slope centered. We descended and entered VFR conditions, executed a practice missed approach, and then returned to our home base.

Original NASA ASRS Text

Title: GA SMA ON A TRAINING FLT DESCENDED BELOW FAF ALT TOO SOON.

Narrative: DURING IMC/IFR CONDITION ON AN ILS 24 APCH INTO ELMIRA ARPT IN NY, WE WERE INTERCEPTING THE LOC TO THE ILS 24. I HAD NEVER FLOWN WITH THE STUDENT BEFORE, BUT I THOUGHT THAT THE STUDENT WAS FAMILIAR WITH HIS OWN FLYING CLUB'S AIRPLANE. THE STUDENT WAS DOING THE RADIO WORK. WE CHECKED THE FREQS AND IDENTIFIERS FOR THE ILS APCH AND THE ADF OUTER MARKER. THE ONLY THING THAT I FORGOT WAS TO CHECK THE ADF NEEDLE FOR THE CORRECT INDICATION. THE CLRNC WAS: MAINTAIN 3300 UNTIL ALPINE, CLRED FOR THE ILS APCH 24. ON THE LOC INBND FOR THE OUTER MARKER AND SUDDENLY THE GLIDE SLOPE MOVED IN BUT JUST A LITTLE. THE STUDENT THEN TOLD ME THAT WE WERE OVER ALPINE. I LOOKED AT THE ADF NEEDLE, AND IT SHOWED 'DEAD' 180 DEGS, SO I LET HIM CONTINUE (WHICH I LATER LEARNED WAS A MISTAKE). WE DESCENDED TO BETWEEN 3000' AND 3100' BEFORE I UNDERSTOOD THAT SOMETHING WAS WRONG. BEFORE EITHER OF US HAD A CHANCE TO APPLY POWER TO LEVEL OFF, ATC CALLED 'LOW ALT ALERT. CHECK ALTIMETER SETTING. MAINTAIN 3300' UNTIL ALPINE.' I APPLIED FULL POWER AND CLIMBED TO 3200' AND THEN THE GLIDE SLOPE CENTERED. WE DESCENDED AND ENTERED VFR CONDITIONS, EXECUTED A PRACTICE MISSED APCH, AND THEN RETURNED TO OUR HOME BASE.

Data retrieved from NASA's ASRS site as of August 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.