Narrative:

Dfw-nrt. On R220 between alaska and japan (the 'north' route). We requested tokyo radio to obtain clearance from FL330 to FL290 after 'nogal' to avoid reported severe turbulence. HF communication was spotty but I read back the clearance twice. Each time tokyo acknowledged by reading back whole clearance. (I assumed he did this because of HF, perhaps he was trying to clarify the fix.) passing nogal, I called departing FL330 for FL290. When we called reaching FL290, tokyo told us we should be at FL330 until 'nogar' (a fix 493 mi down track). It's interesting to note that it took about 3 mins before he could pronounce the 2 fixes differently and then we realized there was a similar sounding fix on the same route. In fact, the 2 fixes (nogal/nogar) are identical, except for the last letter (left/right). Japanese pronounce 'left' and 'right' -- making the words the same as pronounced by tokyo radio. Tokyo immediately amended our clearance to FL290. No traffic conflicts occurred. I think an immediate review of related fix names for similar sounding names as pronounced by the local speaker's language is essential. Not every nation or language can or do speak english the same way native english speakers do. Japanese phonetic differences should be taken into account, especially in japanese airspace. At a minimum 'nogal' should be changed. (Although we don't have our old map to verify, we (the crew) think 'nogal' is a new fix on the route, effective with the may 27 revision. There were major route changes with that revision.)

Related reports:

Google
 

Original NASA ASRS Text

Title: WDB DSNDED FROM 33000 FT TO 29000 FT 493 MI TOO SOON.

Narrative: DFW-NRT. ON R220 BTWN ALASKA AND JAPAN (THE 'N' RTE). WE REQUESTED TOKYO RADIO TO OBTAIN CLRNC FROM FL330 TO FL290 AFTER 'NOGAL' TO AVOID RPTED SEVERE TURB. HF COM WAS SPOTTY BUT I READ BACK THE CLRNC TWICE. EACH TIME TOKYO ACKNOWLEDGED BY READING BACK WHOLE CLRNC. (I ASSUMED HE DID THIS BECAUSE OF HF, PERHAPS HE WAS TRYING TO CLARIFY THE FIX.) PASSING NOGAL, I CALLED DEPARTING FL330 FOR FL290. WHEN WE CALLED REACHING FL290, TOKYO TOLD US WE SHOULD BE AT FL330 UNTIL 'NOGAR' (A FIX 493 MI DOWN TRACK). IT'S INTERESTING TO NOTE THAT IT TOOK ABOUT 3 MINS BEFORE HE COULD PRONOUNCE THE 2 FIXES DIFFERENTLY AND THEN WE REALIZED THERE WAS A SIMILAR SOUNDING FIX ON THE SAME RTE. IN FACT, THE 2 FIXES (NOGAL/NOGAR) ARE IDENTICAL, EXCEPT FOR THE LAST LETTER (L/R). JAPANESE PRONOUNCE 'L' AND 'R' -- MAKING THE WORDS THE SAME AS PRONOUNCED BY TOKYO RADIO. TOKYO IMMEDIATELY AMENDED OUR CLRNC TO FL290. NO TFC CONFLICTS OCCURRED. I THINK AN IMMEDIATE REVIEW OF RELATED FIX NAMES FOR SIMILAR SOUNDING NAMES AS PRONOUNCED BY THE LCL SPEAKER'S LANGUAGE IS ESSENTIAL. NOT EVERY NATION OR LANGUAGE CAN OR DO SPEAK ENGLISH THE SAME WAY NATIVE ENGLISH SPEAKERS DO. JAPANESE PHONETIC DIFFERENCES SHOULD BE TAKEN INTO ACCOUNT, ESPECIALLY IN JAPANESE AIRSPACE. AT A MINIMUM 'NOGAL' SHOULD BE CHANGED. (ALTHOUGH WE DON'T HAVE OUR OLD MAP TO VERIFY, WE (THE CREW) THINK 'NOGAL' IS A NEW FIX ON THE RTE, EFFECTIVE WITH THE MAY 27 REVISION. THERE WERE MAJOR RTE CHANGES WITH THAT REVISION.)

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.