Pilot of light twin loses both directional gyros in hnl airspace.

Attributes
ACN	407470
Time
Date	199807
Day	Tue
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : hnl
State Reference	HI
Altitude	msl bound lower : 3500 msl bound upper : 3500
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : hnl
Operator	common carrier : air taxi
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 135
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	Other
Function	oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 7200 flight time type : 500
ASRS Report	407470
Person 2
Affiliation	government : faa
Function	controller : departure
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : overcame equipment problem
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

While climbing out, my #1 HSI circuit breaker tripped. I reset the breaker and continued on my present heading. I then got into the clouds and to my surprise, found my HSI not working again. I then reset the circuit breaker and tried to use the copilot's directional gyro to steer. The circuit breaker on my #1 HSI tripped again and to my surprise the copilot's heading (directional gyro) had precessed 30 degrees in 15 seconds. I then found myself in the clouds with no directional gyros trying to steer with my magnetic compass. I asked the approach controller to give me vectors toward the ocean and a clearance to descend into VFR conditions. I broke out and accepted a visual approach without further events.

Original NASA ASRS Text

Title: PLT OF LIGHT TWIN LOSES BOTH DIRECTIONAL GYROS IN HNL AIRSPACE.

Narrative: WHILE CLBING OUT, MY #1 HSI CIRCUIT BREAKER TRIPPED. I RESET THE BREAKER AND CONTINUED ON MY PRESENT HDG. I THEN GOT INTO THE CLOUDS AND TO MY SURPRISE, FOUND MY HSI NOT WORKING AGAIN. I THEN RESET THE CIRCUIT BREAKER AND TRIED TO USE THE COPLT'S DIRECTIONAL GYRO TO STEER. THE CIRCUIT BREAKER ON MY #1 HSI TRIPPED AGAIN AND TO MY SURPRISE THE COPLT'S HDG (DIRECTIONAL GYRO) HAD PRECESSED 30 DEGS IN 15 SECONDS. I THEN FOUND MYSELF IN THE CLOUDS WITH NO DIRECTIONAL GYROS TRYING TO STEER WITH MY MAGNETIC COMPASS. I ASKED THE APCH CTLR TO GIVE ME VECTORS TOWARD THE OCEAN AND A CLRNC TO DSND INTO VFR CONDITIONS. I BROKE OUT AND ACCEPTED A VISUAL APCH WITHOUT FURTHER EVENTS.

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.