NSEU
5th Mar 2013, 02:06
After trawling all my manuals and the internet, I failed to find definitive information on the Smart 500 Callout on the 747-400.
An earlier PPRuNe message included this information:
"According to the Flight Manual Supplement for the MKVIII EGPWS System Installation ATR 42 & 72.
To meet the AC’s for installation of EGPWS onto any aircraft there
must be a form of callout for 500 ft. This can be acheived via one
of three options in the EGPWS, as a “Hard 500”, “Smart 500”, or
“500 Above Field” callout. These are included as options in the
Callout Menu items. There are also menus without 500 foot callouts,
these are included for aircraft that already have the means
to announce 500 ft.
1) The “Hard 500” foot callout will annunciate “FIVE HUNDRED” once during each approach.
2) The “Smart 500” foot callout, when selected, will assist pilots during
a non-precision approach by enunciating “FIVE HUNDRED”
feet in addition to any other altitude callout discussed above. The
EGPWS determines a non-precision approach when Glideslope
is greater than 2 dots deviation (valid or not) or a back-course
approach is detected.
3) The “500 Above Field “ callout will be annunciated once during
each approach when the aircraft flies below 500 ft above the landing
field. It compares the GPS-based geometric altitude with the
closest runway. The callout may be optionally chosen to
annunciate “FIVE HUNDRED” or “FIVE HUNDRED ABOVE”."
For the "Smart 500" callout, I don't see what sources are used as a reference or whether it's barometric or radio altimeter-derived. I assume it's not GPS-derived as that's what the "500 Above Field" uses.
Would it use the pilot's FMC entry of arrival airport/runway (i.e. TDZ-based)? Will it work independently of GPS and the Terrain Database in the EGPWS?
Could it be used with QFE landings? (where option fitted).
If the airport/runway is not in the airline's FMC database, will it fail to sound?
An earlier PPRuNe message included this information:
"According to the Flight Manual Supplement for the MKVIII EGPWS System Installation ATR 42 & 72.
To meet the AC’s for installation of EGPWS onto any aircraft there
must be a form of callout for 500 ft. This can be acheived via one
of three options in the EGPWS, as a “Hard 500”, “Smart 500”, or
“500 Above Field” callout. These are included as options in the
Callout Menu items. There are also menus without 500 foot callouts,
these are included for aircraft that already have the means
to announce 500 ft.
1) The “Hard 500” foot callout will annunciate “FIVE HUNDRED” once during each approach.
2) The “Smart 500” foot callout, when selected, will assist pilots during
a non-precision approach by enunciating “FIVE HUNDRED”
feet in addition to any other altitude callout discussed above. The
EGPWS determines a non-precision approach when Glideslope
is greater than 2 dots deviation (valid or not) or a back-course
approach is detected.
3) The “500 Above Field “ callout will be annunciated once during
each approach when the aircraft flies below 500 ft above the landing
field. It compares the GPS-based geometric altitude with the
closest runway. The callout may be optionally chosen to
annunciate “FIVE HUNDRED” or “FIVE HUNDRED ABOVE”."
For the "Smart 500" callout, I don't see what sources are used as a reference or whether it's barometric or radio altimeter-derived. I assume it's not GPS-derived as that's what the "500 Above Field" uses.
Would it use the pilot's FMC entry of arrival airport/runway (i.e. TDZ-based)? Will it work independently of GPS and the Terrain Database in the EGPWS?
Could it be used with QFE landings? (where option fitted).
If the airport/runway is not in the airline's FMC database, will it fail to sound?