ALEXANDRIA, Va., Sept. 3 -- United States Patent no. 12,404,707, issued on Sept. 2, was assigned to The Boeing Co. (Arlington, Va.).

"Systems and methods for preventing a walkway platform flip door from being raised without a guardrail installed" was invented by Don J. Russell (Arlington, Wash.) and Brennan J. Dunlap (Snohomish, Wash.).

According to the abstract* released by the U.S. Patent & Trademark Office: "In an example, a system for preventing a flip door from being raised without a guardrail installed is disclosed. The system includes a guardrail having a post, and the post having a post dog. The system also includes a safety latch mechanism configured to be coupled to a fixed structure. The safety latch mechanism includes a body, ...