terry
April 24th 08, 10:02 PM
Some time ago I started a thread about why the take off distance of a
172 increased at lower temperature for the same density altitude,
while landing distance was just a smooth function of density altitude
only.
Those of you who are familiar with the Cessna take off and landing
tables, will know they are just tables of distance required in a table
with pressure altitude down and temperature across the top of the
page. Well I just took all of these combinations and converted them
to density altitude and plotted them as distance required vs density
altitude for each temperature set.
The excel analysis is now available to download if anyone is
interested in it. If you use the charts correctly , I guess it is of
academic interest only, but if you are like me you would prefer to
read off a graph than tables of numbers, so you might find it useful.
The reason for the temperature effect on take off distance is
apparently related to better engine performance at higher
temperatures. But anyway if like me you thought it was only the
density that mattered, you may want to think again.
The graphs can be found at the link below, which also happens to be
an Australian aviation forum which you are welcome to join, although
you would have to register to join the forum ( to keep the kooks out)
but you dont have to register to acess the Excel applications. This
link will take you straight to the download page.
http://www.straightandleveldownunder.net/index.html
Terry
PPL Downunder
172 increased at lower temperature for the same density altitude,
while landing distance was just a smooth function of density altitude
only.
Those of you who are familiar with the Cessna take off and landing
tables, will know they are just tables of distance required in a table
with pressure altitude down and temperature across the top of the
page. Well I just took all of these combinations and converted them
to density altitude and plotted them as distance required vs density
altitude for each temperature set.
The excel analysis is now available to download if anyone is
interested in it. If you use the charts correctly , I guess it is of
academic interest only, but if you are like me you would prefer to
read off a graph than tables of numbers, so you might find it useful.
The reason for the temperature effect on take off distance is
apparently related to better engine performance at higher
temperatures. But anyway if like me you thought it was only the
density that mattered, you may want to think again.
The graphs can be found at the link below, which also happens to be
an Australian aviation forum which you are welcome to join, although
you would have to register to join the forum ( to keep the kooks out)
but you dont have to register to acess the Excel applications. This
link will take you straight to the download page.
http://www.straightandleveldownunder.net/index.html
Terry
PPL Downunder