B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 217; Flight Crew Type 11000
Aircraft Equipment Problem Less Severe
General None Reported / Taken
Aircraft; Environment - Non Weather Related
This report is NOT meant as a joke. Following an uneventful flight to SJU; on the return flight (with the same aircraft) we received several 'VERIFYPOS: IRS-IRS' (Inertial Reference System) scratch pad messages. Checking POS SHIFT page three/three; we confirmed that our IRS position errors were significant. During this flight; the L IRS position error varied from two to five NM; the R IRS error varied from three to eleven NM. This did not cause any operational problems because our ANP stayed below 0.07 with very tight GPS and RADIO cross tuning accuracy. This defect was recorded in the aircraft logbook at [destination]. I did not think much more about it until I got home and my wife asked 'Any issues today flying thru the Bermuda Triangle?' I never thought about such a coincidence during the flight; but we were within the southern edge of that area. If anyone is seriously tracking empirical data on navigation errors in that area; please pass on this report. I wonder if (Company) has any data on other navigational issues between CONUS and SJU; MDPC or MYNN? I have never seen such IRS accuracy errors in 22 years of operating this aircraft.If anyone is seriously tracking navigation anomalies within the 'Bermuda Triangle'; please forward this report.
B737-NG Captain reported his IRS navigation system showed significant position errors in the area of the 'Bermuda Triangle.'