SAR Fundamentals/Search probability

Scope

 * SAR Fundamentals Manual: Ch.22 "Search Probability Theory", p.293
 * Basic SAR Skills Manual:
 * Ch.12 "Search Management Crucials"
 * Ch.13 "Search Area/Confinement"
 * Search Area / Confinement

Objectives
At the conclusion of this lesson the participants:
 * 1) will be able to ...

Time Plan
Total Time: 45 minutes
 * 2011-03 19:00-19:35: 35 min
 * 2013-02: 25 min


 * Image:Search-probability-lesson-plan.odt

Introduce topic title

Introduce Instructor

Present Objectives


 * Describe what a Search Area is
 * Rest of World - ROW
 * can be just outside search area
 * can be back home, at bar
 * can be some other area completely

Methods to establish Search Area [2]

Start with Initial Planning Point (IPP)

Typically one of two places:
 * Point Last Seen (PLS)
 * Last Known Point (LKP)
 * e.g. strong belief was there - location of car

Theoretical Search Area [2]
 * distance subject could have travelled from LKP. [2]
 * statistical search area [2]
 * subjective search area [2]
 * likely spots [2]
 * natural barriers [2]
 * physical or mental limits of subject [2]
 * physical clues [2]
 * historical data [2]
 * gut feeling [2]
 * deductive reasoning [2]

Confinement [2]
 * requires prompt action [2]
 * tactics [2]
 * vehicle patrols [2]
 * road blocks [2]
 * trail blocks [2]
 * observation posts [2]
 * string lines [2]
 * track traps [2]

Attraction [2]
 * visual: lights, flares, fires, smoke, balloons [2]
 * sound: horns, PA system, shouting [2]
 * aircraft [2]

Segmentation [2]
 * size
 * searchable area in reasonable time
 * boundaries
 * challenge of picking boundaries on map
 * risks of team in adjacent segments leaving a gap
 * may have to flag


 * POA- probability of area, to find the subject [1]
 * POD- probability of detection, of the subject [1]
 * POS- probability of success, of finding the subject. [1]
 * POS= POA X POD [1]


 * Understanding and using this formula helps mgmt., to understand how effective they have been or will be. [1]
 * This helps mgmt., to  [1]
 * Distribute resources [1]
 * Decide on which areas to search/research. [1]
 * How to treat a segment. [1]
 * Suspend a search. [1]
 * Use in court. ( need documentation)  [1]

Effects on POD [1]
 * Searcher prejudice- thoughts of search, subject isn't here!! [1]
 * Searcher fatigue [1]
 * Boredom [1]
 * Weather on visibility/comfort [1]
 * Terrain [1]
 * Anything that affects your senses [1]

POD Influences [1]
 * Time [1]
 * POD desired or accepted [1]
 * Time searcher is available [1]
 * Size of the segment [1]
 * Type and effectiveness of resources [1]
 * Search method [1]

Critical Spacing or Separation [1]
 * The distance from one searcher to another on a grid line.   [1]
 * Figure that will change with terrain. [1]

SAR manager may take these into consideration and adjust the expected/given POD. [1]

POA [1]
 * Probability of area. [1]
 * Could the subject be in that area. [1]

Example
 * Koopmans Search
 * some areas searched 7 times


 * Keeping variables independant
 * Novice searcher will estimate POD as 100%
 * Estimate portion of areas searched separately
 * Which is better? Thorough over long time?  Rapid several times?  Why?

Aids

 * Non-publishable material
 * flip chart or white board
 * suitable markers

Question bank
See

Feedback

 * 2004-09-07 Wuth presentation at PCSAR regular meeting

License
Portions copyright © 2003, Jake Waiboer.

Portions copyright © 2005, 2013 Brett Wuth.

This work is licensed under a Creative Commons Attribution-NonCommercial 2.5 Canada License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc/2.5/ca/ or send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA.

Reference Material
[1] some material from Jake Waiboer developed for this section, provided personally.

[2] SAR Skills Handbook: FOG SAR, Field Operating Guide To Search and Rescue, Richard Smith et al., (c) ERI Canada et al., 2003, first edition, ISBN 0-9734135-0-6, Chapter 13