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6.3 Back Azimuth and Backsighting

A back azimuth is a projection of the azimuth from the origin to the opposite side of the azimuth circle. There are 360 degrees in the azimuth circle, so the opposite direction would be 180 degrees (half of 360 degrees) from the azimuth.

A back azimuth is calculated by adding 180° to the azimuth when the azimuth is less than 180°, or by subtracting 180° from the azimuth if it is more than 180°. For example, if an azimuth is 320°, the back azimuth would be 320° - 180° = 140°. If the azimuth is 30°, the back azimuth would be 180° + 30° = 210°.

Backsighting is a method of sighting that uses an azimuth reading taken backwards. Backsighting uses the azimuth sight and turns it around to find the way back to the original starting point.

Example 1 - Susan is at the lookout point and sights a fire at 100°. She starts out in the direction of the fire, but soon loses sight of the fire. Susan turns around and backsights to the lookout point. It is 260°. How many degrees off course is she? Which direction does Susan need to move to get back on course?

Step 1. The azimuth, 260°, is more than 180°, so subtract 180° from the azimuth. 260°– 180°= 80°

Step 2. Subtract the calculated backsight reading from the original azimuth reading.
100° - 80° = 20°

Susan is 20 degrees off course. 

Because the new azimuth (80°) is less than the original (100°), Susan needs to move to the left to make the back azimuth larger by 20°. When the lookout line of sight back azimuth of 280° is read, she can proceed along the line toward the fire. 

Susan needs to move to the left by 20 degrees. 

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Incident Position Standards and Next Gen Position Task Books Now Available for Dispatch Incident Positions

Date: March 5, 2025
Contact: National Coordination System Committee

NWCG is excited to announce that Incident Position Standards and Next Generation Position Task Books are now available for all six Dispatch positions:

  • Aircraft Dispatcher
  • Expanded Dispatch Coordinator
  • Expanded Dispatch Recorder
  • Expanded Dispatch Supervisory Dispatcher
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The Performance Support Packages for these positions, including the Expanded Dispatch Job Aid, J-601 and the Initial Attack and Aircraft Dispatcher Job Aid, J-602, were developed as part of the Incident Performance and Training Modernization (IPTM) effort. These resources support trainees, qualified personnel, and evaluators in their roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.

References:

NWCG Aircraft Dispatcher Position Page 

NWCG Expanded Dispatch Coordinator Position Page 

NWCG Expanded Dispatch Recorder Position Page 

NWCG Expanded Dispatch Supervisory Dispatcher Position Page 

NWCG Expanded Dispatch Support Dispatcher Position Page 

NWCG Initial Attack Dispatcher Position Page 

NWCG Job Aids 

Incident Position Standards and the Next Generation Position Task Books Now Available for DMOB, DOCL, and RESL

Date: February 28, 2025
Contact: Incident Operations Subcommittee

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for Demobilization Unit Leader (DMOB), Documentation Unit Leader (DOCL), and Resources Unit Leader (RESL).

The Performance Support Packages for these positions, including a job aid for RESL, were developed as part of the Incident Performance and Training Modernization (IPTM) effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.

References:

NWCG Demobilization Unit Leader Position Page 

NWCG Documentation Unit Leader Position Page 

NWCG Resources Unit Leader Position Page 

Next Generation Position Task Book and Updated Incident Position Description Now Available for Operations Section Chief Complex

Date: February 27, 2025
Contact: Incident Operations Subcommittee

NWCG is excited to announce that Operations Section Chief Complex (OSCC) has a Next Generation NWCG Position Task Book for Operations Section Chief Complex (OSCC), PMS 311-108 and an updated Incident Position Description.

These resources support trainees, qualified personnel, and evaluators in their respective roles.

References:

NWCG Operations Section Chief Complex Position Page 

NWCG Operations Section Chief Complex Incident Position Description 

NWCG Position Task Book for Operations Section Chief Complex (OSCC), PMS 311-108 

2025 NWCG Incident Response Pocket Guide (IRPG), PMS 461, Now Available

Date: February 27, 2025
Contact: Incident Operations Subcommittee

NWCG is excited to announce that the 2025 NWCG Incident Response Pocket Guide (IRPG), PMS 461, is now available. Visit NWCG's website to learn about the major updates and changes in the 2025 version of the IRPG. The NWCG Guia de Respuesta de Incidente de Bolsillo (GRI), PMS 461-ES is available electronically and will be available from Great Basin Cache by early summer 2025.

All hard copy materials, including the IRPG, are ordered through the Great Basin Cache (GBK). Information on the ordering process can be found in the National Fire Equipment System (NFES) Catalog.

References:

2025 IRPG Information 

NWCG Incident Response Pocket Guide (IRPG), PMS 461 

NWCG Guia de Respuesta de Incidente de Bolsillo (GRI), PMS 461-ES 

NWCG NFES Catalog - Part 2: Publications, PMS 449-2