plot1_gpscomp_clr.ps - 

A color postscript plot which shows the effect of the GPS correction
on the INS east component of the groundspeed vector.  For comparison
purposes, the GPS correction performed at NOAA/NSSL is also included.
The data presented is from N42RF flying a level and straight leg on 13
November, 1992.  On the lower plot, the UCI and NOAA/NSSL corrections
to the raw INE east component groundspeed are plotted as well as the
difference between raw GPS and raw INE.  In the UCI GPS-correction the
periodic "jumps" (with a period of approx. 30 sec.) in the GPS
groundspeed data are filtered out.  It is believed that these "jumps"
are characteristic of the Trimble 2100 GPS system and are not
representative of the real motion of the aircraft.  For this reason,
as shown in the lower plot, the UCI GPS-corrected groundspeed retains
the high-frequency information of the INE output and uses the low
frequency portion of the GPS data to produce a GPS-corrected INE
groundspeed.


plot1_gpscomp_bw.ps - 

The same plot as plot1_gpscomp_clr.ps, but in black and white.





plot2a_windcomp_clr.ps & plot2b_windcomp_clr.ps -

This pair of color postscript files serve as a check of the UCI wind
calculation.  These data are from a upwind/downwind reverse-heading
maneuver immediately followed by a cross-wind reverse-heading maneuver
performed by N43RF on 28 November, 1992.  For comparison purposes, the
winds calculated by NOAA/AOC and NOAA/NSSL are included in the plot.
The first plot (plot2a_windcomp_clr.ps) shows the latitude, longitude,
heading, and elevation of the aircraft during the maneuvers.  The
second plot (plot2b_windcomp_clr.ps) shows the resulting wind vector.  If
the wind field is assumed to be steady throughout the maneuver, then
the resulting wind vector should show a minimal change independent of
the aircraft heading.  It should be noted that, for this plot only,
the wind direction is not displayed in the normal convention of 0 to
360 degrees.  It is plotted from -180 to 180 degrees.  This is done to
avoid the discontinuity which occurs between 0 and 360 degrees.  The
large jumps in wind direction for the NOAA/NSSL calculated wind
direction (dark blue) indicate that either the wind direction is
extremely variable throughout the maneuver or there is a problem with
the NOAA/NSSL calculated winds.  The vertical wind for NOAA/AOC and
NOAA/NSSL is identical since NOAA/NSSL did not modify the original
vertical wind calculated by NOAA/AOC.


plot3a_windcomp_bw.ps & plot3b_windcomp_bw.ps -

A similar plot to plot2a_windcomp_clr.ps & plot2b_windcomp_clr.ps, but in
black and white.  These data, except wind direction, have been filtered
at 0.05 Hz. so that the differences can be more clearly seen.