NTSB Investigation Reveals Pitch Trim and Dead Recorder in Fatal Philadelphia Learjet Crash

The National Transportation Safety Board’s investigation into a fatal Learjet air ambulance crash near Philadelphia in 2025 has identified two primary areas of focus: pitch trim configuration at the time of the accident and a cockpit voice recorder that was not functioning. The aircraft was operating an air ambulance mission when it went down. The investigation is ongoing.

What the NTSB Has Found So Far

Investigators have released preliminary findings pointing to two distinct concerns. The pitch trim settings at the moment of the accident are under scrutiny, as is the status of the required cockpit voice recorder. Each issue tells a separate story - one about what may have caused the crash, and one about whether the systems meant to explain it were in place.

Why Pitch Trim Is a Focus of the Investigation

Pitch trim controls the baseline attitude of an aircraft, allowing pilots to maintain flight without constant control pressure. In a light training aircraft, a misconfigured trim setting is noticeable and easily corrected. In a jet operating at rotation speeds and beyond, an incorrect trim setting can generate significant control forces almost immediately - forces a crew may not be able to overcome.

The Learjet is a capable, fast, and demanding platform. Originally manufactured by Learjet Incorporated and later acquired by Bombardier, the series spans multiple variants including the Learjet 23, 24, 25, 35, 36, and 45. In air ambulance operations, the Learjet 35 and 36 are particularly common, offering the cabin volume, range, and airport flexibility the mission requires. The type rewards precise systems management and penalizes inattention.

The NTSB has not concluded that trim caused this accident. But when investigators describe something as a focus of the inquiry, it signals that the data already recovered is pointing in that direction. The open questions are specific: Was the trim set incorrectly before departure? Was it altered without crew awareness? Did a system malfunction change the trim state mid-flight? Those answers will emerge as the investigation continues.

The Cockpit Voice Recorder Was Not Functioning

Federal regulations require air carrier aircraft to maintain functioning flight data recorders and cockpit voice recorders (CVRs). These are not optional equipment. A CVR captures the last 30 minutes - or up to two hours in some systems - of cockpit audio: crew conversation, radio transmissions, system alerts, switch sounds, and ambient noise. That record is essential to reconstructing the sequence of events in a fatal accident.

In the Philadelphia crash, the CVR was not functioning. That is a significant finding in its own right, separate from anything the recorder might have captured. Without it, investigators must reconstruct crew actions and the cockpit environment from flight data, radar tracks, witness accounts, and wreckage analysis. The investigation can still reach conclusions, but gaps may remain that a working recorder would have closed.

The cause of the CVR failure has not been determined. Possible explanations include a maintenance deficiency, a failed component not identified during preflight or routine checks, or a circuit or power issue. The NTSB will investigate that question alongside the trim inquiry.

Air Ambulance Operations and the Regulatory Context

Air ambulance flying occupies a specific place in the regulatory landscape. Many operators fall under Part 135 of the Federal Aviation Regulations - the on-demand charter and air taxi framework - though exact requirements can vary based on how a mission is structured. Over the years, the NTSB has issued repeated safety recommendations targeting air ambulance operations: better oversight, stronger crew resource management programs, stricter maintenance standards, and improved crew rest requirements. Some recommendations have been implemented. Others have moved slowly.

When a fatal accident involves both a question about trim and a non-functioning required recorder, it raises broader questions about whether the systems designed to prevent accidents - and to explain them when they occur - were working as intended across the entire operation.

Why This Matters Beyond Air Ambulance Flying

The discipline of trim verification before takeoff is one of the most fundamental elements of airmanship. Trim requirements on departure are defined, published, and part of every checklist for a reason. The Philadelphia investigation is a reminder that this process is not a formality - it is a procedural safeguard with real consequences when it breaks down.

The CVR issue carries a message of equal weight for operators. Required equipment must be functioning. A non-operational recorder is not a minor discrepancy to be deferred; it removes a critical layer of accident investigation capability and may signal a maintenance process that needs attention.

Air ambulance crews fly frequently, at irregular hours, and routinely into challenging conditions - often because the mission demands it. The accident chain in any fatal crash rarely traces to a single cause. The NTSB’s investigation will follow the evidence through scheduling, maintenance records, training, preflight procedures, and crew communication. The final report, when it arrives, will carry recommendations with implications for every Part 135 operator and every pilot flying demanding, time-pressured missions.

Sources: Flying Magazine’s coverage of the NTSB findings; National Transportation Safety Board public investigation records. Investigation ongoing as of 2025.

Key Takeaways

• A fatal Learjet air ambulance crash near Philadelphia in 2025 is under active NTSB investigation.
• Investigators are focused on pitch trim configuration at the time of the accident and a non-functioning cockpit voice recorder.
• In high-performance jets, an incorrect trim setting at rotation can produce severe and rapid control forces - making correct trim verification before takeoff a critical safety discipline, not a checklist formality.
• A non-functioning CVR is itself a significant finding; required equipment must be operational, not deferred.
• The investigation will examine the full accident chain, including maintenance, crew procedures, and regulatory compliance across Part 135 air ambulance operations.