From Newsgroup: alt.astronomy

AI Overview
The longest an unmanned, computer-controlled (autonomous) airplane has
flown without human intervention is approximately 64 days, 18 hours, and
26 minutes.
IFLScience

This record was achieved by the Airbus Zephyr S, a solar-powered
high-altitude pseudo-satellite (HAPS) drone, which crashed in Arizona in August 2022 just hours short of breaking the all-time, crewed endurance
record of 64 days, 22 hours.
IFLScience
IFLScience
+1
Key Details of Autonomous Flight Records
Longest Autonomous Duration (Unmanned): The Zephyr S set this record in
2022 during a test in Arizona, demonstrating the capability of
solar-electric aircraft to stay in the stratosphere for months at a time. Previous Autonomous Record: In 2018, an earlier version of the Zephyr S
held the record with a continuous flight of 25 days, 23 hours, and 57
minutes.
Small Autonomous Plane Record: In 2015, the AtlantikSolar UAV (under
50kg) flew for 81.5 hours (over 4 days and 3 nights) autonomously,
breaking the endurance record for its class.
atlantiksolar
atlantiksolar
+3
Context: Autonomous vs. Crewed
The 65-Day Record (Human): The absolute longest flight without landing
was accomplished by humans in 1959 in a Cessna 172. While they flew for
nearly 65 days, this was a manual flight with only brief periods of
autopilot usage.
Autonomous Evolution: While the 1959 human flight required dangerous
aerial refueling, modern autonomous drones like the Zephyr use solar
power during the day and batteries to stay airborne through the night. IFLScience
IFLScience
+3
Note: In 2023, an AI-controlled fighter jet (F-16) flew for 17 hours,
but this was a test of AI algorithms, not a maximum duration record.

If we can 'fly' an airplane 64 days in 2022,
with no human control, I'm sure our 'starships'
will be able to last longer in 2100.
Computers can control until human communications
will catch up and give more instructions.
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