B757 captain believes that the flight manual requirement to verify aircraft position on the navigati...

Narrative:

As per the B767 flight manual; when lined up on the departure runway; both pilots will visually confirm the airplane symbol on the nd/map display is on the assigned runway and the airplane and runway headings agree (using the lowest scale). If inconsistency is found; do not takeoff. I; and I would assume almost every other B757/B767 flight; cannot meet this requirement in the flight manual; due to the fact that our position update to the takeoff position of the inserted runway in the FMC does not occur until after the takeoff is started and the EPR button is pressed. On almost every flight in the non-GPS aircraft; which is most; the aircraft symbol is not on the assigned runway; in fact it often is very far off. So how is one to comply with the flight manual and ever make a takeoff with the B757 or non-GPS B767 aircraft? This flight manual requirement has no room for interpretation the way it is written. I would estimate that probably 90% of all B757/B767 flights do not meet this requirement but still execute the takeoff. When we get GPS upgrades; this will probably correct itself; but until then the flight manual needs to be changed.

Original NASA ASRS Text

Title: B757 Captain believes that the flight manual requirement to verify aircraft position on the NAV display prior to takeoff is not germane due to the position not being updated in the FMC until the EPR button is pressed for takeoff.

Narrative: As per the B767 flight manual; when lined up on the departure runway; both pilots will visually confirm the airplane symbol on the ND/MAP display is on the assigned runway and the airplane and runway headings agree (using the lowest scale). If inconsistency is found; do not takeoff. I; and I would assume almost every other B757/B767 flight; cannot meet this requirement in the flight manual; due to the fact that our position update to the takeoff position of the inserted runway in the FMC does not occur until after the takeoff is started and the EPR button is pressed. ON almost every flight in the non-GPS aircraft; which is most; the aircraft symbol is not on the assigned runway; in fact it often is very far off. So how is one to comply with the flight manual and ever make a takeoff with the B757 or non-GPS B767 aircraft? This flight manual requirement has no room for interpretation the way it is written. I would estimate that probably 90% of all B757/B767 flights do not meet this requirement but still execute the takeoff. When we get GPS upgrades; this will probably correct itself; but until then the flight manual needs to be changed.

Data retrieved from NASA's ASRS site as of July 2013 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	1018970
Time
Date	201206
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Taxi
Person 1
Function	Pilot Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 155 Flight Crew Total 23000 Flight Crew Type 2700
Events
Anomaly	Deviation - Procedural Published Material / Policy

B757 captain believes that the flight manual requirement to verify aircraft position on the navigation display prior to takeoff is not germane due to the position not being updated in the FMC until the EPR button is pressed for takeoff.