Narrative:

Captain's HSI went blank followed by a wisp of smoke from under the glare shield and an acrid smell. We donned oxygen masks and established communication. I declared an emergency and with an immediate clearance from center we began a turn toward ZZZ. Our distance from ZZZ was approximately 100 mi and at FL320 we found ourselves on a near optimum descent to ZZZ. Smoke was visible for no more than 10 seconds and then dissipated. With the source of smoke known and the smoke dissipated, I elected to continue to ZZZ at best possible speed to land on runway 25R. The WX was VFR and the wind was 240 degrees at 9 KTS. We touched down at a weight of 336000 pounds and rolled to the end to negate possible hot brakes. The emergency trucks were there at my request to observe our wheels and brakes whereupon we taxied to the gate. ATC handling was expeditious and excellent. Supplemental information from acn 628011: on climb out, the captain's HSI went blank. I was the PF, and he asked me to fly the return at maximum speed and talk with ATC on the radio while he worked on other duties. While flying the descent, I got the aircraft set up for the approach and overweight landing at ZZZ. When closer to ZZZ he briefed the approach to runway 25R (wind 240 degrees at 9 KTS) and took the controls on downwind for an uneventful approach and landing. Fire trucks met us at the end to check the brakes, and we taxied to the gate. From a human factors standpoint, I felt the oxygen mask was very tight on my face, and it was time consuming to keep pushing the interphone button and the VHF button for communication. ATC found it difficult to understand my voice through the mask microphone sometimes. I was pressed for time flying, communicating, and getting the FMC, etc, set up for ZZZ, but I was able to do it.

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Original NASA ASRS Text

Title: B767-300 CREW HAD THE CAPT'S HSI GO BLANK, WITH SMOKE AND FUMES IN THE COCKPIT.

Narrative: CAPT'S HSI WENT BLANK FOLLOWED BY A WISP OF SMOKE FROM UNDER THE GLARE SHIELD AND AN ACRID SMELL. WE DONNED OXYGEN MASKS AND ESTABLISHED COM. I DECLARED AN EMER AND WITH AN IMMEDIATE CLRNC FROM CTR WE BEGAN A TURN TOWARD ZZZ. OUR DISTANCE FROM ZZZ WAS APPROX 100 MI AND AT FL320 WE FOUND OURSELVES ON A NEAR OPTIMUM DSCNT TO ZZZ. SMOKE WAS VISIBLE FOR NO MORE THAN 10 SECONDS AND THEN DISSIPATED. WITH THE SOURCE OF SMOKE KNOWN AND THE SMOKE DISSIPATED, I ELECTED TO CONTINUE TO ZZZ AT BEST POSSIBLE SPD TO LAND ON RWY 25R. THE WX WAS VFR AND THE WIND WAS 240 DEGS AT 9 KTS. WE TOUCHED DOWN AT A WT OF 336000 LBS AND ROLLED TO THE END TO NEGATE POSSIBLE HOT BRAKES. THE EMER TRUCKS WERE THERE AT MY REQUEST TO OBSERVE OUR WHEELS AND BRAKES WHEREUPON WE TAXIED TO THE GATE. ATC HANDLING WAS EXPEDITIOUS AND EXCELLENT. SUPPLEMENTAL INFO FROM ACN 628011: ON CLBOUT, THE CAPT'S HSI WENT BLANK. I WAS THE PF, AND HE ASKED ME TO FLY THE RETURN AT MAX SPD AND TALK WITH ATC ON THE RADIO WHILE HE WORKED ON OTHER DUTIES. WHILE FLYING THE DSCNT, I GOT THE ACFT SET UP FOR THE APCH AND OVERWT LNDG AT ZZZ. WHEN CLOSER TO ZZZ HE BRIEFED THE APCH TO RWY 25R (WIND 240 DEGS AT 9 KTS) AND TOOK THE CTLS ON DOWNWIND FOR AN UNEVENTFUL APCH AND LNDG. FIRE TRUCKS MET US AT THE END TO CHK THE BRAKES, AND WE TAXIED TO THE GATE. FROM A HUMAN FACTORS STANDPOINT, I FELT THE OXYGEN MASK WAS VERY TIGHT ON MY FACE, AND IT WAS TIME CONSUMING TO KEEP PUSHING THE INTERPHONE BUTTON AND THE VHF BUTTON FOR COM. ATC FOUND IT DIFFICULT TO UNDERSTAND MY VOICE THROUGH THE MASK MIC SOMETIMES. I WAS PRESSED FOR TIME FLYING, COMMUNICATING, AND GETTING THE FMC, ETC, SET UP FOR ZZZ, BUT I WAS ABLE TO DO IT.

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.