Atx pilot on FAA part 135 check ride descends on approach without clearance.

Attributes
ACN	145933
Time
Date	199005
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : gij airport : sbn
State Reference	IN
Altitude	msl bound lower : 2500 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air taxi
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	descent : approach
Route In Use	enroute airway : sbn enroute other
Flight Plan	IFR
Person 1
Affiliation	company : air taxi
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 26 flight time total : 2933
ASRS Report	145933
Person 2
Affiliation	government : faa
Function	observation : air carrier inspector
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : published procedure non adherence : clearance
Independent Detector	other controllera other other : unspecified
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was on an FAA 135 flight check. My initial clearance was to maintain 3000' and a heading of 060 degrees. 4 mi west of the VOR 18 DME arc I received a clearance to join the DME arc. The controller at this time did not issue me an altitude. I took this clearance to mean I should join the 8 mi DME arc and use it as my IAF, as depicted on the approach chart. Upon reaching and joining the 8 mi arc, I began my descent to 2100'. The radio frequency was busy with idle chatter, so I was unable to report out of 3000' until I was at 2500'. The controller then wanted to verify my altitude at 2500'. The controller then cleared me to maintain 2500' until intercepting the final approach course inbound. I broke my clearance by not maintaining 3000', as I was only cleared to join the DME arc, not cleared for the approach. The controller was not busy at the time and I feel his clearance was vague. He should have stated that I was to maintain 3000' until the final approach course inbound. The controllers at sbn most often keep pilot's altitude high when on a published approach. At times this makes it very difficult in a piston aircraft to descend to the FAF. I feel this altitude error was the result of miscom between the controller and myself.

Original NASA ASRS Text

Title: ATX PLT ON FAA PART 135 CHECK RIDE DESCENDS ON APCH WITHOUT CLRNC.

Narrative: I WAS ON AN FAA 135 FLT CHK. MY INITIAL CLRNC WAS TO MAINTAIN 3000' AND A HDG OF 060 DEGS. 4 MI W OF THE VOR 18 DME ARC I RECEIVED A CLRNC TO JOIN THE DME ARC. THE CTLR AT THIS TIME DID NOT ISSUE ME AN ALT. I TOOK THIS CLRNC TO MEAN I SHOULD JOIN THE 8 MI DME ARC AND USE IT AS MY IAF, AS DEPICTED ON THE APCH CHART. UPON REACHING AND JOINING THE 8 MI ARC, I BEGAN MY DSNT TO 2100'. THE RADIO FREQ WAS BUSY WITH IDLE CHATTER, SO I WAS UNABLE TO RPT OUT OF 3000' UNTIL I WAS AT 2500'. THE CTLR THEN WANTED TO VERIFY MY ALT AT 2500'. THE CTLR THEN CLRED ME TO MAINTAIN 2500' UNTIL INTERCEPTING THE FINAL APCH COURSE INBND. I BROKE MY CLRNC BY NOT MAINTAINING 3000', AS I WAS ONLY CLRED TO JOIN THE DME ARC, NOT CLRED FOR THE APCH. THE CTLR WAS NOT BUSY AT THE TIME AND I FEEL HIS CLRNC WAS VAGUE. HE SHOULD HAVE STATED THAT I WAS TO MAINTAIN 3000' UNTIL THE FINAL APCH COURSE INBND. THE CTLRS AT SBN MOST OFTEN KEEP PLT'S ALT HIGH WHEN ON A PUBLISHED APCH. AT TIMES THIS MAKES IT VERY DIFFICULT IN A PISTON ACFT TO DSND TO THE FAF. I FEEL THIS ALT ERROR WAS THE RESULT OF MISCOM BTWN THE CTLR AND MYSELF.

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.