Inland Search Considerations
If a search is required, the Land SAR Addendum provides a questionnaire (11 pages, primarily for lost individuals). The key focus areas are:
- Last known position/time.
- Activity: hiking, hunting, skiing, foraging, etc.
- Route, departure point, destination, itinerary.
- Clothing and gear: color, visibility, appropriateness.
- Comms/signaling gear.
- Experience: outdoor skills, survival background, military or SAR training.
- Age, fitness, injuries, medical conditions.
- Behavioral clues: decision-making patterns.
The general search sequence is:
1. Electronic Search.
2. Visual Search Initiation.
a. Attraction.
b. Containment.
3. Hasty Search.
4. Organized Search.
Phase 1 – Electronic Search. The electronic search begins en route and continues throughout all subsequent phases. Crews should monitor all relevant radio frequencies (including guard and SAR coordination channels) and actively employ direction-finding (DF) equipment, and electro-optical/infrared (EO/IR) sensors. This phase also includes cross-checking mission data with any active PLBs, ELTs, cell phone pings, or satellite communicators (e.g., inReach, SPOT). These tools can help triangulate survivor location, even before visual contact is possible.
Phase 2 – Visual Search Initiation. Phase 2 consists of two integrated sub-phases: Attraction and Containment.
Phase 2a. – Attraction Phase. Attraction begins upon arrival at the search area. The goal is to position the helicopter where it can be both seen and heard by the survivor, encouraging signaling or movement. The attraction phase typically involves a climb to a higher-than-normal altitude to establish a visible orbit over or around the search area with the intent that the aircraft’s lights, sound, and movement prompts the survivor to signal or move into the open to be seen. If confidence in the survivor’s location is high, this phase may be shortened or skipped. If confidence is low, it may be worthwhile to extend this phase to maximize detection opportunities.
Phase 2b. – Containment Phase. Containment defines the boundaries within which the survivor is most likely to be found, based on both time and terrain.
Distance containment estimates how far the subject could have traveled since their last known position/time. This varies based on mobility:
- On foot in rugged terrain: ~2 mph.
- On trails or flat ground: up to ~4 mph.
- With vehicles (e.g., snow machines, ATVs, mountain bikes, horses): significantly farther.
- Example: a subject missing for 5 hours and likely traveling on foot may be within a 10-mile radius.
Feature containment uses natural terrain to limit movement and other elements that would allow someone to be found:
- Examples of terrain that would limit movement include fast-moving rivers, cliffs, shorelines, thick forests, or steep escarpments.
- Examples of containment elements that would allow someone to be found include highways and neighborhoods that border wilderness areas.
These features help refine the search area and focus aerial efforts. During the attraction phase, the aircrew should confirm or adjust containment assumptions made during preflight planning by evaluating terrain and obstacles visually. This live terrain assessment helps validate the expected containment area.
Phase 3 – Hasty Search. The hasty search focuses on high-probability locations based on likely subject behavior. It’s the first tactical search effort after containment is established.
- The intended travel route or trail the subject was known or expected to follow.
- All trail junctions, spurs, and possible decision points where the subject could have turned.
- Clearings, cabins, fishing or hunting sites, shelters, and other logical destinations.
- Drainages and natural travel corridors (paths of least resistance).
- Coordinate with other ground or air units to avoid duplication. Use crew intuition to assess places where the subject may have made a wrong turn or become disoriented. Focus first on the most likely areas and expand from there.
Phase 4 – Organized Search. If hasty search efforts return no result (NEGRES), transition to a systematic, thorough search of the entire containment area using one or more structured search patterns:
- Contour search: used along ridgelines, shorelines, or mountainsides. Works well when flown top-down (high to low) to maximize visibility into terrain features. Step down a reasonable distance each pass using barometric altitudes.
- Track line search: follow known or likely travel paths, using route offsets or parallel track patterns.
- Expanding square search: centered around a last known position or high-probability area. Adjust leg lengths and spacing based on terrain and probability of detection. Effective when datum is known and travel could have been in any direction.
- Sector search: similar to the expanding square with a more concentrated effort closer to datum.
Altitude, Airspeed, and Search Optimization. Select an altitude and airspeed that balance coverage area with probability of detection.
Consider:
- Air taxi: Low, slow passes optimize visibility into dense vegetation or tree canopy but cover less ground.
- Higher altitudes/faster speeds: Extend search range but may reduce visual detail and detection likelihood.
Adjust your search profile based on:
- Vegetation density and terrain type.
- Light and weather conditions.
- Presence of signaling devices.
- EO/IR imagery quality and capabilities.
- Distance to be covered and on scene endurance.
