PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Commercial; Flight Crew Flight Instructor
Flight Crew Last 90 Days 15; Flight Crew Total 330; Flight Crew Type 316
Distraction; Human-Machine Interface; Situational Awareness
Deviation - Altitude Excursion From Assigned Altitude; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Human Factors
I am a student in training to get my Instrument Instructor license. I was practicing a LOC BC and was cleared for the approach outside of the FAF. As we began to descend from 3;000 MSL; we entered IMC. I began to concentrate too much on the navigation instruments instead of my altimeter. When I finally looked at my altimeter; I did not immediately recognize that I had gone below the minimums of the approach. I descended below the FAF minimum of 2;200 MSL and the CFII in the airplane had to take the controls and climb us back up. To fix this problem; I will have to increase my rate of scanning the instruments and make sure I do not fixate on one instrument. I will continually remind myself while on an approach of the altitudes I am cleared for and make sure I do not descend below them.
I was acting as a flight instructor while instructing another flight instructor seeking his CFII rating. While inbound on a LOC BC he [descended below] a step down altitude by 400-500 FT. This approach was being done via radar vectors. We were told to maintain 3;000 FT until established; cleared LOC BC approach. We were 5.9 DME from the localizer and he proceeded to descend to 2;200 MSL. We were descending at 1;000 FT per minute which I have always taught was on the steep end for a non precision descent. I had glanced at the altimeter when it read 2;300 FT and then moved on to other things while instructing him.  The airplane descended from 2;300 FT to 1;700-1;800 FT MSL without him or myself noticing that he had passed the step down altitude; which was 2;200 FT MSL. As soon as I noticed I put the throttle to full and started a Vx climb. No low altitude alerts were given; possibly because we were close to XXX. (4.3DME). For this reason I have learned that even a flight instructor can get behind the airplane. This is something that I have not experienced when instructing my four other CFII candidates in the same weather conditions. In the future I will be more diligent in scanning the altimeter.
PA28 CFII and his student report descent below the FAF altitude before reaching the fix. The student was having trouble with altitude in actual IMC and the instructor was distracted with instructing.