Narrative:

[We were] cleared kennedy 1 departure; breezy point climb. Departure was discussed in depth during the takeoff briefing; as kennedy is noise sensitive and this was an old 757. It has been my experience that the older 757's are slow to respond to LNAV commands when turns are required immediately after takeoff. This may either be due to age of equipment or a saturated FMC memory. Due to this experience with the 757; we decided to initially use heading sel at 400 ft to make the immediate turn to cri. Cri was pre-loaded in the FMC so that once established inbound; cri would be executed and made the active waypoint and LNAV would be used. This is exactly the sequence of events we performed immediately after takeoff. Cri was tuned in the captains VOR as a backup; although the VOR was left in automatic to aid in IRS updating. Map position was normal for takeoff; although this is not an RNAV 1 departure. Just prior to the turn from our inbound course to cri (in LNAV); to the outbound 223 to rngrr; departure asked 'what departure were you given?' I responded kennedy one breezy point climb. Departure responded 'well you missed the VOR.' by our map; at this exact time; we were not quite over the cri VOR; but were tracking direct to it in LNAV and the flight director was beginning to command a turn which was being followed exactly by the aircraft. I responded we did show over the VOR (which by this time we did). Departure then issued a 180 heading and later told us to intercept V16 out of jfk. Departure then said we had missed cri by a 'mile or mile and a quarter.' manual was selected on my VOR (cri preselected) and it appeared to confirm our position (by then) as just slightly right; and past; the VOR; which LNAV/autopilot was tracking. Since the controller seemed adamant we were further northwest I reported a possible map shift and informed him we would use raw data to track V16. I tuned jfk and raw data was compared with our map; which matched. The flight director v-bars were followed exactly and standard bank was used. It appeared the aircraft symbol was slightly (1/16' on lowest HSI map scale) outside the magenta nav line during our turn over cri. Sometime during this sequence autopilot was engaged; but the exact timing is unknown due to the running conversation with departure control. Upon arrival a logbook entry was made concerning the incident and a possible map shift. Both pilots believe any map shift; if one occurred at all; was extremely minor. Raw data was compared to FMC map during the entire route with no discrepancies noted. If this had been an RNAV 1 departure autopilot/LNAV would have been used at 400 ft; however I think (on an older 757) this may have caused an even greater nav error (if one actually occurred at all). Our older equipment seems to have trouble on these departures; especially when accelerating.

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Original NASA ASRS Text

Title: A non GPS equipped B757 departed JFK on the Kennedy 1 Breezy Point Climb and missed the CRI VOR. A map shift is believed to have occurred because even though the ND showed the aircraft over the VOR; ATC claimed it missed by a mile.

Narrative: [We were] cleared Kennedy 1 Departure; Breezy Point Climb. Departure was discussed in depth during the takeoff briefing; as Kennedy is noise sensitive and this was an old 757. It has been my experience that the older 757's are slow to respond to LNAV commands when turns are required immediately after takeoff. This may either be due to age of equipment or a saturated FMC memory. Due to this experience with the 757; we decided to initially use HDG SEL at 400 FT to make the immediate turn to CRI. CRI was pre-loaded in the FMC so that once established inbound; CRI would be executed and made the active waypoint and LNAV would be used. This is exactly the sequence of events we performed immediately after takeoff. CRI was tuned in the Captains VOR as a backup; although the VOR was left in AUTO to aid in IRS updating. Map position was normal for takeoff; although this is NOT an RNAV 1 departure. Just prior to the turn from our inbound course to CRI (in LNAV); to the outbound 223 to RNGRR; Departure asked 'what departure were you given?' I responded Kennedy One Breezy Point Climb. Departure responded 'well you missed the VOR.' By our map; at this exact time; we were not quite over the CRI VOR; but were tracking direct to it in LNAV and the Flight Director was beginning to command a turn which was being followed exactly by the aircraft. I responded we did show over the VOR (which by this time we did). Departure then issued a 180 heading and later told us to intercept V16 out of JFK. Departure then said we had missed CRI by a 'mile or mile and a quarter.' Manual was selected on my VOR (CRI preselected) and it appeared to confirm our position (by then) as just slightly right; and past; the VOR; which LNAV/Autopilot was tracking. Since the Controller seemed adamant we were further northwest I reported a possible map shift and informed him we would use raw data to track V16. I tuned JFK and raw data was compared with our map; which matched. The Flight Director V-Bars were followed exactly and standard bank was used. It appeared the aircraft symbol was slightly (1/16' on lowest HSI map scale) outside the magenta nav line during our turn over CRI. Sometime during this sequence autopilot was engaged; but the exact timing is unknown due to the running conversation with Departure Control. Upon arrival a logbook entry was made concerning the incident and a possible map shift. Both pilots believe any map shift; if one occurred at all; was extremely minor. Raw data was compared to FMC map during the entire route with no discrepancies noted. If this had been an RNAV 1 departure autopilot/LNAV would have been used at 400 FT; however I think (on an older 757) this may have caused an even greater nav error (if one actually occurred at all). Our older equipment seems to have trouble on these departures; especially when accelerating.

Data retrieved from NASA's ASRS site as of April 2012 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.