In SRU pattern designations, the second letter indicates:

• A. The weather conditions
• B. The number of search units
• C. The direction of travel
• D. The scale of the search area

Answer: (B)

In SRU pattern designations, the second letter tells you how many search units are assigned to the pattern. That count directly affects how the search is laid out—more units mean parallel lanes of coverage, faster overall reach, and greater redundancy, while fewer units conserve resources but may take longer and risk gaps. The other aspects of the plan (like weather conditions, direction of travel, or the overall scale of the search area) are not conveyed by this letter; they’re determined by other elements of the designation and briefing.