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Firefighter Math: 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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RMC Safety Bulletin 26-001: Rhabdomyolysis in Wildland Firefighters

Date:  May 28, 2026
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Please contact: Risk Management Committee

The Risk Management Committee (RMC) has issued Safety Bulletin 26-001: Rhabdomyolysis in Wildland Firefighters. Research from 2016 to 2025 shows that 88 cases of rhabdomyolysis (rhabdo) were reported. Analysis of reports from eSafety, the Safety Management Information System (SMIS), and the Wildland Fire Lessons Learned Center (LLC) indicates that rhabdo is common during this time of year due to Work Capacity Tests and contributing factors such as weather, hydration, nutrition, and medication or supplement use.

RMC issued this safety bulletin to raise awareness in the Wildland Fire Community, and to provide research findings and educational resources that support reducing future cases of rhabdo.

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RMC Safety Bulletin 26-001: Rhabdomyolysis in Wildland Firefighters

NEW! D-110, Expanded Dispatch Recorder Course Available Now

Date:  May 15, 2026
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Please contact: Dispatch Position and Curriculum Management Subcommittee

NWCG is pleased to announce the new D-110, Expanded Dispatch Recorder (Instructor-led) course is now available on the Wildland Fire Learning Portal (WFLP). Developed through the National Coordination System Committee, this course introduces the structure and function of expanded dispatch, the qualities of an effective dispatcher, and provides hands-on experience with the Interagency Resource Ordering Capability (IROC) system. 

The D-110, Expanded Dispatch Recorder course aligns with the competencies and duties outlined in the NWCG Incident Position Standards for Expanded Dispatch Recorder, PMS 350-59, and is designed for individuals with no prior experience who may be called upon to support dispatch operations.

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Leadership Committee IAP Flyer Now Available

Date:  May 8, 2026
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The NWCG Leadership Committee promotes and enables leadership development across the wildland fire service. The committee provides education, training opportunities, and support for leadership innovation and best practices throughout the community.

A new IAP flyer is now available on the committee website, offering an overview of the products, curriculum, and learning opportunities the Leadership Committee develops. This resource is ideal for posting in your office, sharing with new employees, or distributing through your incident management teams to engage new voices in the leadership journey and reinforce a culture of self‑reflection, development, and growth.

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Incident Operations Subcommittee Updates the Next Generation Position Task Book for FFT1

Date:  May 7, 2026
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The NWCG Incident Operations Subcommittee (IOSC) has updated the NWCG Position Task Book for Firefighter Type 1 (Squad Boss) (FFT1), PMS 311‑14. The FFT1 Position Task Book transitioned to the Next Generation (Next Gen PTB) format in June 2025 through the Incident Performance and Training Modernization effort. Since then, IOSC has received feedback from the wildland fire community regarding coding for one of the tasks. Task #13 has been updated to include the option of evaluation in a simulation.

See IOSC Memorandum 26‑01: Transition Plan for Implementation of Updates to the NWCG Position Task Book for Firefighter Type 1 (Squad Boss) (FFT1), PMS 311‑14 for more information.

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IOSC Memorandum 26-01: Transition Plan for Implementation of Updates to the NWCG Position Task Book for Firefighter Type 1

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