Instructor pilot of an small transport training flight started descent before being cleared to do so...

Attributes
ACN	282686
Time
Date	199409
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ehf airport : bfl
State Reference	CA
Altitude	msl bound lower : 8700 msl bound upper : 9000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Small Transport
Flight Phase	cruise other
Route In Use	arrival other arrival star : star enroute airway : bfl
Flight Plan	IFR
Person 1
Affiliation	Other
Function	instruction : instructor
Qualification	pilot : atp pilot : cfi pilot : commercial pilot : instrument
Experience	flight time last 90 days : 259 flight time total : 2200 flight time type : 410
ASRS Report	282686
Person 2
Affiliation	Other
Function	instruction : trainee
Qualification	pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : published procedure non adherence : clearance
Independent Detector	atc equipment other atc equipment : unspecified other controllera
Resolutory Action	controller : issued new clearance other
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While flying the arvin 1 arrival into bakersfield (on an IFR flight plan in VMC) we had an altitude deviation of 300 ft. I thought that once we were cleared for the arvin 1 arrival, the routing and altitude that are published applied. After crossing kelen intersection (43 DME from palmdale) we were starting our descent from our assigned altitude (on clearance) 9000 ft to the published 8000 ft on the chart, once passing kelen intersection. Bakersfield cleared (approach) us for the approach (ILS 30R) and proceeded to tell us that we could not descend until told to do so. I thanked the controller and proceeded with the approach. On the ground I called the tower to talk with the controller and was given the explanation for his reason. I thanked him and will never again mistake these altitudes for descent until told to descend by approach. The controller said these altitudes were to be flown only in case of lost communication. I now understand and will comply.

Original NASA ASRS Text

Title: INSTRUCTOR PLT OF AN SMT TRAINING FLT STARTED DSCNT BEFORE BEING CLRED TO DO SO.

Narrative: WHILE FLYING THE ARVIN 1 ARR INTO BAKERSFIELD (ON AN IFR FLT PLAN IN VMC) WE HAD AN ALTDEV OF 300 FT. I THOUGHT THAT ONCE WE WERE CLRED FOR THE ARVIN 1 ARR, THE RTING AND ALT THAT ARE PUBLISHED APPLIED. AFTER XING KELEN INTXN (43 DME FROM PALMDALE) WE WERE STARTING OUR DSCNT FROM OUR ASSIGNED ALT (ON CLRNC) 9000 FT TO THE PUBLISHED 8000 FT ON THE CHART, ONCE PASSING KELEN INTXN. BAKERSFIELD CLRED (APCH) US FOR THE APCH (ILS 30R) AND PROCEEDED TO TELL US THAT WE COULD NOT DSND UNTIL TOLD TO DO SO. I THANKED THE CTLR AND PROCEEDED WITH THE APCH. ON THE GND I CALLED THE TWR TO TALK WITH THE CTLR AND WAS GIVEN THE EXPLANATION FOR HIS REASON. I THANKED HIM AND WILL NEVER AGAIN MISTAKE THESE ALTS FOR DSCNT UNTIL TOLD TO DSND BY APCH. THE CTLR SAID THESE ALTS WERE TO BE FLOWN ONLY IN CASE OF LOST COM. I NOW UNDERSTAND AND WILL COMPLY.

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.