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Many may be interested?

I thought that there will be an interest in the USNAVY instruction below. It 
is not classified, so there is no harm in the information. There may be some 
errors in this rewrite, but the info  is correct.  I have the complete 
instruction about 100 pages; I selected these as giving the basic to the 
instruction. (Of course the Intrepid I had 30 QM's to use as I saw fit for  
navigation safety. No one man show, I had a plotting team, to ensure the 
safety of this valuable ship with some times 5000 (crew and air crew)people 
on board. Navigation has stopped many Captains from making the next 
promotion. The CO that has good navigation people can feel safe in his 
command. The Intrepid had 5 CO during my stay; all made admiral except the 
one that ran aground.   Before I came aboard.
It is big news for a major ship to hit the bottom. Note that 2 minute fixes 
are also required and that Celestial is mentioned More than once. I will copy 
more for your info if desired.) The Date is 2005 but it is very close to any 
new REGS. Its in selected parts.
 
COMNAVAIRFORINST 3530. 4A/COMNAVSURFORINST 3530. 4A
24 Feb 05
Has a significant error. By integrating as many sources information as is 
reasonably possible, mutually support will improve position accuracy and 
raise the confidence ą produced. The integration of all Navigation Sensors to 
 most probable position involves:
(1) Understanding those factors influencing the day or seasonal variation and effectiveness.
(2) Precise data collection, plotting, and analyst the precise time set for 
fixing the ship's position as re
By Table 3-A.
(3) Noting variation in fix clusters in successive plots, and remain alert to the first indication of acc
Degradation in the data.
(4) Flagging all geodetic positioning data pro7id the users of navigation 
information, with an assessment  
Quality (excellent, good, or poor).
Table 3-A
FIX ACCURACY AND FIX INTERVAL GUIDELINES
(Note I had to retype the below. But the standard below is the same as in my days.  Up to 1978)
Standards for fixing the ship's position and the interval.. Between these 
fixes are, to some extent, situation dependent
Restricted	Less than 2nm	50 yards/	2 minutes
Pilot water          2-10 nm               100yards             3 to 10 minutes as conditions warrants
Coastal Waters      10-30                     500 yards          15 to 30 minutes as condition Warrants  
Open ocean           over 30 nm           1500 yards        30 minutes as condition Warrants 






COMNAVAIRFORINST 3530. 4A/
COMNAVSURFORINST 3530. 4A
24 Feb 05
2 good rule of thumb for fix intervals is, "if a hazard to
 navigation falls within a circle whose radius is that of two DR intervals," 
then either the fix interval or ship's speed requires adjusting.
3 waters are defined in each ship's CO's Standing Orders and may be different for each class of ship.
4 ships using GPS as the primary fix source are required to obtain a visual 
and/or RADAR fix at 3 times the intervals indicated (i.e. every six minutes 
in restricted waters). If GPS FOM exceeds those limits listed above, GPS will 
not be used as the primary fix source, except in cases where no other fix 
source (excluding celestial) is available.
c. Ensure charts (paper and electronic) to be used are certified safe for 
navigation and corrected/updated using all available information, (i.e. 
Notice to Mariners, Local Notice to Mariners, Broadcast Notice to Mariners, 
NAVAREA5, HYDROPAC/LANTs, VDU) and all area charts are compared to ensure 
that hazards to navigation are properly displayed and highlighted on all 
charts in use. In the event the Navigator determines the largest-scale chart 
obtainable from NGA is insufficient for use during the transit, he/she should 
take action as early as possible to obtain NGA-sanctioned foreign- produced 
charts. In the event a ship is unexpectedly tasked to pilot in waters not 
covered by sufficiently large-scale NGA charts, Navigators must make every 
effort to obtain corrections via immediate message (or VDU) from NGA for the 
chart being used. Navigators must verify the geodetic system on which the 
chart is based and ensure adjustments are made to the GPS equipment to match 
the chart datum The Navigator must also determine the scale. units of 
measurement, and other pertinent characteristics of the chart prior to its 
use and take appropriate action to ensure the chart is safely and properly 
used.
d. Ensure all required navigation equipment is on board, maintained in 
accordance with PMS requirements, and operating properly. The status of 
equipment pertaining to the safe navigation and operation of the ship will be 
reviewed. The appropriate department head will provide Estimated Time of 
Repair (ETR).


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