Corp mdt on SID climbed before designated position.

Attributes
ACN	95411
Time
Date	198810
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mdw
State Reference	IL
Altitude	msl bound lower : 2000 msl bound upper : 2800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord
Operator	general aviation : corporate
Make Model Name	Medium Transport, Low Wing, 2 Turboprop Eng
Flight Phase	climbout : intermediate altitude
Route In Use	departure sid : sid
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : instrument
ASRS Report	95411
Person 2
Affiliation	Other
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : overshoot non adherence : clearance non adherence : published procedure
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

We were cleared mdw, canal 3 SID, radar vectors sbn direct fwa. I followed the SID by departing runway 31L climbing through 1300' MSL, turned right to assigned heading of 90 degrees. I had my (pilot's) HSI set up for the 340 degree right off of cgt VOR, as I passed through the 340 degree right off of cgt VOR I climbed through 2000' MSL to 3000' MSL as we were leveling off for 3000' MSL (we only got to 2800'). Chi departure said we should be at 2000' MSL. I started back to 2000' MSL. Chi departure asked how we were cleared. Copilot told him we were cleared canal 3 SID. Departure then told us to stay at 3000', so I climbed back to 3000' MSL. Departure gave us a telephone # to call. Then I checked HSI and it was wrong by 9 degrees. The 340 degree right I got off of cgt VOR was actually 331 degree right. That started me climbing about 4 mi too early from 2000 to 3000' MSL. I switched my gyros to copilot's remote compass, which allowed my dg's to work properly. On takeoff it seemed to operate properly. We had the plane in shop the next day to fix the problem.

Original NASA ASRS Text

Title: CORP MDT ON SID CLIMBED BEFORE DESIGNATED POSITION.

Narrative: WE WERE CLRED MDW, CANAL 3 SID, RADAR VECTORS SBN DIRECT FWA. I FOLLOWED THE SID BY DEPARTING RWY 31L CLBING THROUGH 1300' MSL, TURNED RIGHT TO ASSIGNED HDG OF 90 DEGS. I HAD MY (PLT'S) HSI SET UP FOR THE 340 DEG R OFF OF CGT VOR, AS I PASSED THROUGH THE 340 DEG R OFF OF CGT VOR I CLBED THROUGH 2000' MSL TO 3000' MSL AS WE WERE LEVELING OFF FOR 3000' MSL (WE ONLY GOT TO 2800'). CHI DEP SAID WE SHOULD BE AT 2000' MSL. I STARTED BACK TO 2000' MSL. CHI DEP ASKED HOW WE WERE CLRED. COPLT TOLD HIM WE WERE CLRED CANAL 3 SID. DEP THEN TOLD US TO STAY AT 3000', SO I CLBED BACK TO 3000' MSL. DEP GAVE US A TELEPHONE # TO CALL. THEN I CHKED HSI AND IT WAS WRONG BY 9 DEGS. THE 340 DEG R I GOT OFF OF CGT VOR WAS ACTUALLY 331 DEG R. THAT STARTED ME CLBING ABOUT 4 MI TOO EARLY FROM 2000 TO 3000' MSL. I SWITCHED MY GYROS TO COPLT'S REMOTE COMPASS, WHICH ALLOWED MY DG'S TO WORK PROPERLY. ON TKOF IT SEEMED TO OPERATE PROPERLY. WE HAD THE PLANE IN SHOP THE NEXT DAY TO FIX THE PROB.

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.