Air carrier captain reported noticing a potential for a navigation error involving two fixes with si...

Narrative:

While performing a last minute runway change; out of the blocks; resolving a discontinuity; I saw a potential source for a routing error. Two of the waypoints are spelled very similarly. They are: prymd; which is part of the ducks 4RNAV SID; and the other waypoint is pyrmd; which [is] an enroute waypoint used in our departure clearance. These two waypoints are somewhat close to each other; when resolving a discontinuity on the FMS. We brought up this in our HF (human factors) briefing; and my crew agreed with reporting this potential departure/routing conflict to light. The cause of this event is difficult to pinpoint; since the pronunciation and spelling are different for those two waypoints. This oversight was caught by following company procedures which calls for slowing down when faced by a disruption; and pay attention to details. Enroute ATC planners were not aware of the waypoint similarities to the mem SID waypoint in question; ie. Pyrmd vs prymd.immediately rename one of the two waypoints in question. In the future; more coordination between authorities to avoid future conflicts; especially during these new times of more FMS direct routing clearance procedures.

Original NASA ASRS Text

Title: Air carrier Captain reported noticing a potential for a navigation error involving two fixes with similar spelling - PRYMD and PYRMD - while preparing for departure from MEM.

Narrative: While performing a last minute runway change; out of the blocks; resolving a discontinuity; I saw a potential source for a routing error. Two of the waypoints are spelled very similarly. They are: PRYMD; which is part of the DUCKS 4RNAV SID; and the other waypoint is PYRMD; which [is] an enroute waypoint used in our departure clearance. These two waypoints are somewhat close to each other; when resolving a discontinuity on the FMS. We brought up this in our HF (human factors) briefing; and my crew agreed with reporting this potential departure/routing conflict to light. The cause of this event is difficult to pinpoint; since the pronunciation and spelling are different for those two waypoints. This oversight was caught by following company procedures which calls for slowing down when faced by a disruption; and pay attention to details. Enroute ATC planners were not aware of the waypoint similarities to the MEM SID waypoint in question; ie. PYRMD vs PRYMD.Immediately rename one of the two waypoints in question. In the future; more coordination between authorities to avoid future conflicts; especially during these new times of more FMS direct routing clearance procedures.

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.

Attributes
ACN	1496149
Time
Date	201711
Local Time Of Day	0001-0600
Place
Locale Reference	MEM.Airport
State Reference	TN
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	Widebody Transport
Operating Under FAR Part	Part 121
Flight Phase	Parked
Flight Plan	IFR
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	ATC Issue All Types

Air carrier captain reported noticing a potential for a navigation error involving two fixes with similar spelling - prymd and pyrmd - while preparing for departure from mem.