Small aircraft making practice NDB approach descends below assigned altitude.

Attributes
ACN	343606
Time
Date	199608
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : rbl
State Reference	CA
Altitude	msl bound lower : 3200 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa
Operator	general aviation : instructional
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	Other
Function	observation : observer
Qualification	pilot : atp
Experience	flight time last 90 days : 45 flight time total : 12000 flight time type : 1000
ASRS Report	343606
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 13 flight time total : 287 flight time type : 8
ASRS Report	343600
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : far 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:

Pilot under hood on training flight departed assigned altitude due to misunderstanding approach clearance. Controller (ZOA) contributed to confusion by only clearing aircraft for procedure but not the entire approach. PIC was foreign and was having difficulty understanding fast talking controller who was very busy. Clearance was, 'proceed on the VOR 33 approach and I'll clear you on the procedure turn inbound.' this created situation where PIC started approach and was 800 ft below assigned altitude. WX was VMC, visibility 60 NM, no hazard, but good learning situation. Supplemental information from acn 343600: I read back the clearance without altitude because I was not sure.

Original NASA ASRS Text

Title: SMA MAKING PRACTICE NDB APCH DSNDS BELOW ASSIGNED ALT.

Narrative: PLT UNDER HOOD ON TRAINING FLT DEPARTED ASSIGNED ALT DUE TO MISUNDERSTANDING APCH CLRNC. CTLR (ZOA) CONTRIBUTED TO CONFUSION BY ONLY CLRING ACFT FOR PROC BUT NOT THE ENTIRE APCH. PIC WAS FOREIGN AND WAS HAVING DIFFICULTY UNDERSTANDING FAST TALKING CTLR WHO WAS VERY BUSY. CLRNC WAS, 'PROCEED ON THE VOR 33 APCH AND I'LL CLR YOU ON THE PROC TURN INBOUND.' THIS CREATED SIT WHERE PIC STARTED APCH AND WAS 800 FT BELOW ASSIGNED ALT. WX WAS VMC, VISIBILITY 60 NM, NO HAZARD, BUT GOOD LEARNING SIT. SUPPLEMENTAL INFO FROM ACN 343600: I READ BACK THE CLRNC WITHOUT ALT BECAUSE I WAS NOT SURE.

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.