737e GPWS upgrade

[Walter Sobchak]

Hello,

my company upgraded our 737e's with new GPWS. Having terrain awareness is a great thing, but as we didn't get any documentation yet, nobody is able to interpret the following:
two 3digit numbers in the lower right corner of the EHSI in mapmode. They vary with overflown terrain and set range and must be some sort of min altitudes. I checked any published altitude available, but I don't find anything with matches 100 percent. Any advice?

the Walter

[CaptainSandL]

Sounds like you have the Peaks display.

The two overlaid numbers are the highest and lowest terrain elevations, in hundreds of ft amsl, currently being displayed. In the photo below you have 5900ft and 800ft amsl.

http://www.b737.org.uk/ehsi_peaks.jpg

For the full colour decode see http://www.b737.org.uk/warningsystems.htm

[End_of_Descent]

I agree, sounds like Peaks Mode display.

Some information can be found on Honeywell's EGPWS site. Check out the site at
http://www.egpws.com/general_information/description/peaks_mode.htm
and the paper at
http://www.egpws.com/general_information/description/peaks.pdf

Note that with Peaks Mode available, the EGPWS terrain is able to show terrain even when more than 2000' below the aircraft. In this case, the only colour on the display is green. The highest peaks are painted in solid green.

On some displays where blue colour (other than cyan) is available - usually LCDs only - Peaks Mode EGPWS is able to display sea level elevation with blue colour. This feature can be pin-programmed. Nice example is this Swiss A340:
http://www.airliners.net/open.file/425851/L/

EoD

[Walter Sobchak]

quick and helpful

thanks a lot:D