Narrative:

After takeoff from pit and checking on with departure we were given direct to ahtiy waypoint. We entered the waypoint from our flight plan and before activating it we noted that after our heading flown the waypoint was behind us. I asked departure if we could instead get a fix ahead of us. He informed us he was unable so I confirmed that we were proceeding direct to ahtiy behind us. While in the turn departure asked if we were direct to ahtiy. This was an odd question so I double checked the flight plan and discovered that we had misspelled ahtiy as ahity. As it happens ahity is within 30nm of ahtiy. And to add to the confusion it was actually in line with our route of flight so the error was not caught by checking route distance or looking at the route for errors. In addition even in checking the flight plan ahtiy and ahity look so similar that it's easy to overlook it. I explained the confusion to ATC and no flight disruptions resulted. Other than a letter by letter route spelling cross check; the only other suggestion I can offer is to question how smart it is to have two similarly spelled and sounding waypoints in such close proximity to each other. While ultimately the error was mine. Had the two waypoints been 100nm from each other the mistake would have been obvious.

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Original NASA ASRS Text

Title: ERJ-170 flight crew reported becoming confused by two similar fix names in the vicinity of PIT that were only 30 nm apart - AHTIY and AHITY.

Narrative: After takeoff from PIT and checking on with departure we were given direct to AHTIY waypoint. We entered the waypoint from our flight plan and before activating it we noted that after our heading flown the waypoint was behind us. I asked departure if we could instead get a fix ahead of us. He informed us he was unable so I confirmed that we were proceeding direct to AHTIY behind us. While in the turn departure asked if we were direct to AHTIY. This was an odd question so I double checked the flight plan and discovered that we had misspelled AHTIY as AHITY. As it happens AHITY is within 30nm of AHTIY. And to add to the confusion it was actually in line with our route of flight so the error was not caught by checking route distance or looking at the route for errors. In addition even in checking the flight plan AHTIY and AHITY look so similar that it's easy to overlook it. I explained the confusion to ATC and no flight disruptions resulted. Other than a letter by letter route spelling cross check; the only other suggestion I can offer is to question how smart it is to have two similarly spelled and sounding waypoints in such close proximity to each other. While ultimately the error was mine. Had the two waypoints been 100nm from each other the mistake would have been obvious.

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.