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Firefighter Math: 6.6 Vectors

A vector has a magnitude (often representing distance or speed) and direction. When a clinometer (see Section 4.5) is used to estimate the slope percent and the slope length is measured with a metal tape, the result is a vector. The slope length represent the magnitude and the slope percent can be converted into a slope angle that represents direction. Vectors can provide information about the distance and direction of fire spread, or the speed and direction of fire spread or wind. 

Example 1 - Linda is standing at point A. John is standing at point B. John reads the clinometer and finds a slope percent of 25 percent. They measure the slope length and get 18 feet. Draw the vector from point A and then again from point B.

Step 1. Following the steps in Section 4.5, convert the 25 percent to an angle with a calculator using inverse tan (tan-1).

tan A = 0.25, angle A = 14°

Step 2. Draw the vectors. 

image of vectors drawn with length and angle

WIND VECTORS

Wind is the horizontal movement of air relative to the surface of Earth. Recall from Section 6.2 that the wind direction is named by the direction from which the wind is blowing. If the wind is northerly, then the wind is coming from the north. When the wind is blowing into your face, the wind would be named from the direction you are facing. For example, Mandy is facing south and the wind is blowing into her face. The wind is said to be a southerly wind.

 

NWCG Latest Announcements

NWCG Committees Observe Suicide Prevention Awareness Week: September 7-13, 2026

Date:  September 8, 2026
Questions? 
Please contact: Health and Wellness Subcommittee

The NWCG Health and Wellness Subcommittee (HWSC) and Safety/Risk Management Committee (SRC) recognize the unique challenges and demands faced by the wildland fire community. The HWSC and SRC know that we are all stronger together and believe in fostering a culture of support, understanding, and resilience.

Suicide Prevention Awareness encourages us to actively connect with and support each other. For more information that could make a difference for yourself or someone else please review the materials and resources provided for the 2026 Suicide Prevention Awareness Week.

References:

2026 Letter from Leadership

988 Suicide & Crisis Lifeline

Health and Wellness Subcommittee

Safety and Risk Management Committee

2025 Paul Gleason Award Winners Announced

Date:  August 13, 2026
Questions? 
Please contact: Leadership Development Subcommittee

The NWCG Qualifications Management Committee (QMC) and Leadership Development Subcommittee (LDSC) are proud to announce the recipients of the 2025 Paul Gleason "Lead By Example" awards. Award categories include Initiative and Innovation, Mentoring and Teamwork, and Motivation and Vision.

Congratulations to the awardees:

  • Hunter Bell, U.S. Forest Service — Initiative and Innovation
  • Shannon Deane, U.S. Wildland Fire Service— Initiative and Innovation
  • Chris Delaney, U.S. Wildland Fire Service — Motivation and Vision
  • Sean Peterson, U.S. Forest Service — Mentoring and Teamwork

References:

Paul Gleason Lead By Example Award

Wildland Fire Leadership Development Program (WFLDP)

Leadership Development Subcommittee

LMC Equipment Bulletin 26-001: Aquatic Invasive Species – Seasonal Reminder for Mussels

Date:  July 30, 2026
Questions? 
Please contact: Equipment and Technology Subcommittee

The Logistics and Equipment Management Committee (LMC) issued Equipment Bulletin 26-001: Aquatic Invasive Species - Seasonal Reminder for Mussels, reminding the wildland fire community that aquatic mussels continue to be a problem. Mussels rapidly colonize hard and soft surfaces, including aquatic plants and fire equipment, clogging pipes, fouling motors, disrupting water systems, and impacting native species.

To help prevent their spread, fire personnel must follow the decontamination procedures outlined in the NWCG Guide to Preventing Aquatic Invasive Species Transport by Wildland Fire Operations, PMS 444. Additionally, report any sightings immediately to your Lead Resource Advisor and include clear, close-up photos (with a pen or your hand for size reference) and location details.”

Read the complete LMC Equipment Bulletin 26-001, to learn more. 

References:

NWCG Alerts

LMC Equipment Bulletin 26-001: Aquatic Invasive Species - Seasonal Reminder for Mussels

NWCG Guide to Preventing Aquatic Invasive Species Transport by Wildland Fire Operations, PMS 444

Intermediate Faller (FAL2) Position Task Book Update

Date:  July 24, 2026
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Please contact: Tree Felling Subcommittee

NWCG Operations Management Committee (OMC) has issued an update to the NWCG Position Task Book for Intermediate Faller (FAL2), PMS 311-91. To ensure clarity for both trainees and evaluators, the updated FAL2 Position Task Book (PTB) explicitly states who is authorized to sign off on your tasks:

“Evaluators must be qualified as a FAL2, or an Advanced Faller (FAL1).”

If you are currently working out of a previously published version of the FAL2 PTB, you do not need to restart. However, OMC highly encourages you to take the following step to prevent any confusion in the field:

  • Print and replace the updated evaluator information page (page 2) in your current physical PTB.

References:

Intermediate Faller (FAL2) Position Page

RMC Memo 26-01: Transition Plan for Implementing Updates to Intermediate Faller (FAL2) Position Qualifications

NWCG Position Task Book for Intermediate Faller (FAL2), PMS 311-91