The fallback claim reveals the anticipated failure, and in the air the anticipated failure is not reaching your destination. US11250713B2, granted to Honeywell in February 2022, is an "Unmanned aerial vehicle off-site landing system" — a plan for where a drone goes when it cannot finish the mission.
Classified under G08G 5/025 (air traffic management) and B64C 39/024 (UAVs), the patent describes selecting and executing an alternate landing site when conditions — low battery, weather, a malfunction — make the planned destination unreachable. This is the aerial equivalent of the minimal-risk condition that ground AVs invoke when they pull over and stop.
Here is why the off-site landing is the honest part of any drone story. A delivery drone that always reaches its target is a marketing video. A drone fleet that operates over real cities will have aircraft that develop problems mid-flight, and the question that decides whether the program is safe is: where does a compromised drone come down? Patenting the answer is conceding the question is real.
The hard part the patent implies is site selection under constraint. An off-site landing system has to find a spot that is reachable with the energy remaining, clear of people and property, and acceptable to airspace rules — all computed in the moments after something goes wrong. That is a real-time optimization problem dressed as a safety feature.
That an aerospace incumbent like Honeywell holds this is a maturity signal. The startups chase delivery throughput; the established safety-systems players patent the failure modes. Both are necessary, but only the second gets a fleet certified to fly over your neighborhood.
For readers tracking drone autonomy, the off-site landing patent is the right thing to look for. Anyone can show a drone completing a delivery. The serious operators can tell you, in patented detail, what happens when one cannot — and that plan is the difference between a pilot and a service.