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6.8 Intersection

Intersection is a method of locating a point on a map by intersecting lines from two known landmarks on the ground. Intersection is one method fire lookouts use in determining the location of a fire. The procedure is as follows:

  1. From the first position, point 1, take a compass reading of the object or fire.
  2. Adjust for declination.
  3. With a compass or protractor, plot this azimuth on the map.
  4. Draw a line from point 1 beyond the point of the object or fire.
  5. Move down the road to a second position, or radio to the second person's location and get that azimuth reading. Repeat steps 2 through 4.
  6. A third and maybe a fourth reading will help further describe the location.
  7. The object or fire is located where the individual lines cross.

Example 1 - Tom is at a lookout tower at point A. He spots a fire and takes a compass reading. The magnetic azimuth is 277°. He radios to John at tower B, who tells him his magnetic azimuth on the fire is 337°. The declination for the area is 16°E. Plot the lines to find the location of the fire. 

Step 1. Convert the magnetic azimuths to true azimuths by adjusting for declination (see Section 6.5).
277° + 16° = 293°
337°+ 16°= 353°

Step 2. Draw the lines of the azimuth from each point well past the fire.

2 lines crossing

Step 3. Read where the two lines intersect to get the location of the fire.

NWCG Latest Announcements

Updated NWCG Standards for Water Scooping Operations, PMS 518

Date: December 19, 2024
Contact: Water Scooper Operations Unit

The NWCG Standards for Water Scooping Operations, PMS 518 establishes the standards for dispatching, utilizing, and coordinating water scooping aircraft on interagency wildland fires. These standards should be used in conjunction with the NWCG Standards for Aerial Supervision (SAS), PMS 505, and any local, state, or geographic/regional water scooping plans.

References:

NWCG Standards for Water Scooping Operations, PMS 518

Updated NWCG Standards for Aerial Supervision, PMS 505

Date: December 19, 2024
Contact: Interagency Aerial Supervision Subcommittee

The Interagency Aerial Supervision Subcommittee has updated the NWCG Standards for Aerial Supervision, PMS 505. PMS 505 establishes standards for aerial supervision operations for national interagency wildland fire operations. 

References:

NWCG Standards for Aerial Supervision, PMS 505

New Job Aids Available: Packing Lists for Wildland Fire Fireline Personnel and Support Staff, J-101 and J-102

Date: December 3, 2024
Contact: NWCG TRAINING

Two new job aids are now available: Packing List for Wildland Fire Fireline Personnel, J-101 and Packing List for Wildland Fire Support Personnel, J-102, should serve as a baseline for items needed on a wildland fire assignment. These lists will help personnel prepare for a 14 to 21-day assignment on the fireline or in a support role.

References:

Job Aid Catalog

NWCG Packing List for Wildland Fire Fireline Personnel, J-101

NWCG Packing List for Wildland Fire Support Staff, J-102

NWCG Equipment Technology Committee Releases Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention

Date: November 14, 2024
Contact: Equipment Technology Committee

The Equipment Technology Committee (ETC) has released Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention. Misaligned toolless fuel caps on Stihl chainsaws have led to recurring fuel spillage, fuel ignition, and burn injuries during wildland fire management operations.

This Safety Warning is intended to highlight the details and recommended procedures for the installation of a Stihl chainsaw toolless fuel cap, as well as how to identify and correct a misaligned, damaged, or broken fuel cap to help prevent fuel spillage.

References:

NWCG Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention

Advertencia de equipos 24-001: Prevención de derrames de la tapa de combustible sin herramientas de la motosierra Stihl

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