On Fri, 12 Jun 2009 03:54:29 +0000 (UTC), Clark
wrote:

Jackie wrote in
:

[snip]

Does precision approach radar require a transponder to report altitude?

PAR uses a height finder radar to provide sufficient vertical resolution for
precision approaches.

Mode C only provides 100 foot altitude resolution. bzzzzt!

Mode C provides a height eg 1252ft which is deemed only accurate to
100ft because the calibration errors are limited to 100ft.