Narrative:

Preflight, taxi, and takeoff was normal other than the mixed crew. Captain was from mia, first officer was from lax, and flight crew was from ord. Gorman 2 departure, which had never been flown by any of the pilots on board, was flown. PF went runway heading until told by ZLA to turn right heading 360 degrees and climb to 9000 ft. After turn was made, PF directed PNF to arm LNAV, which PNF did. ATC told flight to intercept the gorman 2 departure. Both HSI's were set on a very small scale and gorman was not visible on either screen. A magenta line appeared and PF followed it to a heading of 270 degrees. After approximately 1-2 mins, ATC asked flight what its heading was and that we were supposed to be heading 360 degrees until intercepting the departure. PF engaged heading select again and turned to 360 degrees. ATC then told flight to come further right to 060 degrees, which PF did. Flight was chastised by ATC and then given TA's of a DC10 at 12 O'clock and 1 mi, 1000 ft above. Traffic was in sight and flight got back on the departure without further problems. None of the flight crew could figure out where the extraneous magenta line ever came from or was going to. This was an aircraft which helped to confuse all pilots just enough so that our situational awareness was slightly reduced. Supplemental information from acn 457711: the LNAV intercepted a stray pink line (I have no idea where it came from) and turned to 270 degree heading and followed it. Queried by ATC about heading and confusion about route, we went 200 ft past 9000 ft (our leveloff altitude). In the future, I will always have a raw data backup displayed, even at the very familiar airports.

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Original NASA ASRS Text

Title: A B767 FLC WAS INCAPABLE OF FLYING THE ASSIGNED DEP FROM LAX.

Narrative: PREFLT, TAXI, AND TKOF WAS NORMAL OTHER THAN THE MIXED CREW. CAPT WAS FROM MIA, FO WAS FROM LAX, AND FLC WAS FROM ORD. GORMAN 2 DEP, WHICH HAD NEVER BEEN FLOWN BY ANY OF THE PLTS ON BOARD, WAS FLOWN. PF WENT RWY HDG UNTIL TOLD BY ZLA TO TURN R HDG 360 DEGS AND CLB TO 9000 FT. AFTER TURN WAS MADE, PF DIRECTED PNF TO ARM LNAV, WHICH PNF DID. ATC TOLD FLT TO INTERCEPT THE GORMAN 2 DEP. BOTH HSI'S WERE SET ON A VERY SMALL SCALE AND GORMAN WAS NOT VISIBLE ON EITHER SCREEN. A MAGENTA LINE APPEARED AND PF FOLLOWED IT TO A HDG OF 270 DEGS. AFTER APPROX 1-2 MINS, ATC ASKED FLT WHAT ITS HDG WAS AND THAT WE WERE SUPPOSED TO BE HDG 360 DEGS UNTIL INTERCEPTING THE DEP. PF ENGAGED HDG SELECT AGAIN AND TURNED TO 360 DEGS. ATC THEN TOLD FLT TO COME FURTHER R TO 060 DEGS, WHICH PF DID. FLT WAS CHASTISED BY ATC AND THEN GIVEN TA'S OF A DC10 AT 12 O'CLOCK AND 1 MI, 1000 FT ABOVE. TFC WAS IN SIGHT AND FLT GOT BACK ON THE DEP WITHOUT FURTHER PROBS. NONE OF THE FLC COULD FIGURE OUT WHERE THE EXTRANEOUS MAGENTA LINE EVER CAME FROM OR WAS GOING TO. THIS WAS AN ACFT WHICH HELPED TO CONFUSE ALL PLTS JUST ENOUGH SO THAT OUR SITUATIONAL AWARENESS WAS SLIGHTLY REDUCED. SUPPLEMENTAL INFO FROM ACN 457711: THE LNAV INTERCEPTED A STRAY PINK LINE (I HAVE NO IDEA WHERE IT CAME FROM) AND TURNED TO 270 DEG HDG AND FOLLOWED IT. QUERIED BY ATC ABOUT HDG AND CONFUSION ABOUT RTE, WE WENT 200 FT PAST 9000 FT (OUR LEVELOFF ALT). IN THE FUTURE, I WILL ALWAYS HAVE A RAW DATA BACKUP DISPLAYED, EVEN AT THE VERY FAMILIAR ARPTS.

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.