TLDHS Project

We performed Software Safety Analysis on a large C++ codebase for the Target Location, Designation, and Handoff System (TLDHS), fielded by the United States Marine Corp.

The TLDHS is used by Forward Air Controllers (FACs) or Forward Observers (FO) to call in Close Air Support (planes) or Indirect Fires (artillery), respectively. The FAC or FO uses a laser range-finder to identify a target. This data is passed to the TLDHS tablet computer, which uses its GPS location to accurately determine the location of the target. This information is passed via radio in a digital message to aircraft overhead or to the Fires network.

By sending the mission information digitally, instead of by voice, accuracy and speed are both improved. This helps reduce targeting errors and as a result, fratricide.

We became responsible to lead the Safety team, and successfully obtained “Milestone-C” approval. We were the Principal for Safety for the project. We developed all the MIL-STD-882E documentation needed, including:

  • PESHE
  • SSPP
  • SSHAR
  • SAR
  • Detailed Safety-specific Test plans and procedures

Our efforts on the System Safety project included reviewing 1000’s of lines of C++ code, analyzing requirements and designs for potential safety impacts, and briefing upper Program Management regularly on the current safety issues, risks, and mitigations.

We developed all the safety-related test plans and procedures, modifying and adding to them throughout the product lifecycle. We ran these tests at every test event and formally reported results to senior management.

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