TM 1-1520-238-MTF
4-27
Change 3
ATK Error = 0.54% Distance Travelled
NOTE
This represents value (a) for use in Steps h
and i. Each leg would be calculated in the
same manner and become the next letter for
use in steps h and i.
h. Calculate Root Mean Square of the six (6)
Crosstrack Errors:
Formula:
XTK
(a)2 (b)2 (c)2 (d)2 (e)2 (f)2
6
NOTE
This note is only applicable for use in the
non–integrated navigation mode.
If this result exceeds 1.40%, HARS input
heading data to the Doppler is faulty.
i. Calculate the root mean square of the six (6)
Alongtrack Errors:
Formula:
ATK
(a)2 (b)2 (c)2 (d)2 (e)2 (f)2
6
NOTE
This note is only applicable for use in the
non–integrated navigation mode.
If this result exceeds 0.95%, Doppler ve-
locity is faulty.
j. If the results of calculations performed in
steps h and i are acceptable, navigation
system performance is within tolerance.
