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Elevation Pointing Errors

         tilt of A-frame        observed elevation pointing error
                                wheel   1      2      3      4
            2.72"                     -2.25   2.12   0.74  -0.57 "
     i.e.   1.00"                     -0.83   0.78   0.27  -0.21 "
Assuming simple addition of effects from both A-frames,

del = 0.80 * RY + 0.24 * LY

where RY and LY are the tilts of the Right and Left A-frames.

Currently, the elevation pointing is corrected using TY (PITCH), and from analysis of recent inclinometry data (950527cw, 950609cw & 950609ccw) :

TY = (0.75 + 0.05) * RY + (0.05 + 0.05) * LY

The relationship between the TMU tilt measure of PITCH and the observed elevation pointing error is : 
         PITCH by               observed elevation pointing error
        inclinometry            wheel   1      2      3      4
            2.49"                     -2.25   2.12   0.74  -0.57 "
   i.e.     1.00"                     -0.90   0.85   0.30  -0.23 "
or
            del  =   -0.87 * PITCH   for wheels 1 & 2
            del  =   -0.27 * PITCH   for wheels 3 & 4


Iain Coulson
Wed Mar 12 15:06:27 HST 1997