Narrative:

The flight event started as a quick turn. We received the clearance 'as filed.' the captain inserted the flight plan into the FMS. What he inserted was Zmbro6 odi - KG72k - KG72M... I verified the route and agreed it was correct. I used the total distance to destination and time to cross check ourselves and everything was within regular limits. During our climb out shortly after ATC asked if we were deviating as there was weather. He replied negative that we are flying as filed. He then pulled out the release and read it to ATC with route page on the FMS pulled up as to verify what I was reading. As he was doing this we saw why we were being asked and realized the fix entered KG72k was really filed as KG78K. He informed the controller that we had it now entered in the FMS and could accept direct which he then cleared us for and we continued on our way.we've all entered incorrect fixes before; but never in 5 years of flying commercially have I seen a fix one number off of another that was less than 20-30 degrees off and within about 10 miles of each other. This was an honest mistake on our part but if these fixes aren't changed to be less similar from each other in sure this will happen again. KG72K and KG78K should be hundreds or thousands of miles apart; not practically on the same airway as each other.

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Original NASA ASRS Text

Title: EMB-170 flight crew reported of two fixes that were similar in name and closer than they liked; causing a heading issue with ATC. Captain reported that he had never been trained in this type of fix naming and did not know what to look for to crosscheck it.

Narrative: The flight event started as a quick turn. We received the clearance 'As filed.' The Captain inserted the flight plan into the FMS. What he inserted was Zmbro6 ODI - KG72k - KG72M... I verified the route and agreed it was correct. I used the total distance to destination and time to cross check ourselves and everything was within regular limits. During our climb out shortly after ATC asked if we were deviating as there was weather. He replied negative that we are flying as filed. He then pulled out the release and read it to ATC with route page on the FMS pulled up as to verify what I was reading. As he was doing this we saw why we were being asked and realized the Fix entered KG72k was really filed as KG78K. He informed the controller that we had it now entered in the FMS and could accept direct which he then cleared us for and we continued on our way.We've all entered incorrect fixes before; but never in 5 years of flying commercially have I seen a fix one number off of another that was less than 20-30 degrees off and within about 10 miles of each other. This was an honest mistake on our part but if these fixes aren't changed to be less similar from each other in sure this will happen again. KG72K and KG78K should be hundreds or thousands of miles apart; not practically on the same airway as each other.

Data retrieved from NASA's ASRS site 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.