Junior Navigation
This site is provided as a means of communications with the USPS National Offshore Navigation Committee (ONCom). We welcome your questions and comments on our courses, Learning Guides, and associated materials.
R/C Steven R Abbott, N
Stf/C Larry G. Samuels, SN
Stf/C Victor B. Schwartz, SN
Topics
|
|
|
|
|
|
News
New Celestial Tools Program
There is a new version (v3.5.0) of the Celestial Tools program on the ONCom Tools web page. This version includes a fix for the Windows Vista and 7 printing problem previously reported. (17 Mar 13)
JN12 Update and Errata
An update and an errata sheet are available under the JN Downloadable Materials page. Updated JN12 Chapter 13 Homework PPts (5798KB) are also available on the JN Downloadable Materials page under PowerPoint Files. This file corrects minor errors on slides 17 and 23. (30 Jan 13)
On-The-Water Component to the Junior Navigation Course
The new Junior Navigation On-The-Water Teaching Aid Guide is now available for download. (18 Feb 12)
USPS Local Telephone Number in Course Manuals
Some Junior Navigation course student and instructor manuals have an incorrect local telephone number for USPS Headquarters on the Acknowledgments Page. The correct local telephone number is 919-821-0281. The toll-free number is still 1-888-367-8777 (1-888-FOR-USPS). (21 Dec 10)
Sight Plot Update
Before the days of GPS, it was customary to plot an estimated position (EP) when only one Line of Position (LOP) was available for positioning. As you know, the EP is that point on an LOP which is closest to the reference DR position. Now that GPS positions are available, there is no longer a need for an EP as long as the GPS is operating properly. If there is no reason to question the GPS accuracy, we can reduce a sight from the GPS position and use the resultant LOP to determine our sight-taking accuracy. The important point to remember is that EPs are associated only with DR reference positions; sight accuracy is associated with GPS reference positions.
The following procedure indicates how sights are to be plotted and labeled on CLS or UPS plotting sheets:
Plot and label the reference position, which can be a DR or a GPS position. Lay out the intercept (as a dashed line) in the direction of the azimuth (toward or away). At the terminus of the intercept, construct the LOP perpendicular to the intercept. Label the LOP above the line with the zone time of the sight and below the line with the name of the body. If the reference position is a DR, indicate the EP at the intersection of the intercept and the LOP with a square, and record the EP coordinates at the bottom of the CLS form. If the reference position is a GPS position, an EP is not meaningful; just record the sight error (SErr) at the bottom of the CLS form as the distance in nautical miles from the known position to the LOP. Until the word reaches everyone in the field, exam answers or sight folders won't be marked wrong if the old EP convention is used. (29 Oct 08)
Junior Navigation (JN12) Began Shipping Spring 2012
The JN12 course incorporates the plotting clarifications explained above, and eliminates known position (KP) references. All sight reduction reference points (L and Lo) are either DR or GPS. Known JN07 errata were eliminated. The JN12 Instructor Manual (IM) is in stock now. It contains lesson plans, quizzes and homework solutions. It comes with a CD containing PowerPoint presentations for classes, and quiz and homework solutions. (01 Nov 12)
Junior Navigation Course Description
Junior Navigation is the first in a two-part program of study in offshore navigation, followed by the Navigation course. It is designed as a practical "how to" course. Subject matter includes:
- Precise time determination
- Use of the Nautical Almanac
- Taking sextant sights of the sun
- Reducing sights to establish lines of position
- Special charts and plotting sheets for offshore navigation
- Offshore navigational routines for recreational craft
In Junior Navigation, the student will continue to use GPS as the primary position sensor, as they learned to do in Piloting and Advanced Piloting. However, the offshore environment poses many different elements for consideration by the Navigator. Ocean currents, wind, and sea state all affect a vessel's performance over the longer passages.
Also, visible terrestrial landmarks are no longer available to the navigator as reference points. In the Junior Navigation course, the student will learn to substitute celestial objects such as the sun as reference points. The course begins with the study of celestial navigation, teaching the student to take sights on the sun with a marine sextant and derive a line of position from that observation. Next, the student will apply the principles learned in Advanced Piloting, and plot a running fix from two sun sights taken about fours apart. Once the student has learned the basics of celestial sight reduction, the course continues with planning, positioning, and checking one’s position in the offshore environment, using both electronic and celestial tools.
The new JN12 Instructor Manual for this course includes lesson plans for each chapter and comes with a PowerPoint CD that contains class presentations, quiz and homework answers. The chapter 13 Practice Cruise, and some other homework answers, shown in the Instructor Manual (IM) were calculated using appropriate mathematic methods to produce accurate reproducible answers. Students using the course required graphical methods, are not expected to obtain the identical answers as listed in the IM. Grading tolerances will be allowed.
There are two examination elements for the JN course, the Sight Folder and an Open Book Exam. The sight folder is graded at the squadron level. The Sight Certification Form (SC07) must be submitted with the completed open book exam for the exam to be evaluated when it is submitted to Headquarters.
Check out the Education Department Catalogue for ordering information of the Junior Navigation JN12 course and instructor materials. (01 Nov 12)
Questions or Comments?
If you have any questions or comments about the Junior Navigation course, please contact the National Offshore Navigation Committee chair by e-mail, phone or postal service mail. Please be sure to keep your SEO and/or DEO advised of any correspondence you may have with the National committee. Addresses for the National ONCom chair are listed in The ENSIGN and on the Committee Chairpersons page.
We will try to answer your questions as soon as possible, but please allow 5 working days for an answer.
 |
|
|