"The Learjet’s last radio transmission occurred while climbing through approximately 23,000 feet."
The NTSB records the aircraft reporting flight level 230 at 9.27 a.m., followed by its final acknowledgement of clearance to flight level 390. This altitude provides the factual connection to the December 2025 King Air event, which also experienced its critical pressurization problem while climbing through approximately 23,000 feet.
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