NTSB: Post-Maintenance Stall Test Flight Safety Concerns for Certain Hawker Airplanes

The National Transportation Safety Board (NTSB) recently issued urgent safety recommendations to Textron Aviation Inc. (the type certificate holder) and the Federal Aviation Administration (FAA) to address safety issues the NTSB identified in its recent investigations of two fatal accidents that occurred during manufacturer-required postmaintenance stall test flights of Hawker 800XP and 900XP airplanes. The accidents resulted in five fatalities.

Textron requires that stall test flights must be performed for Hawker 750, 800, 800XP, 850XP, 900XP, and other airplanes on the same type certificate (A3EU) after certain maintenance tasks. This is because these airplanes feature a wing design that is sensitive to minor installation or condition defects that may be introduced inadvertently during maintenance activities. For example, the range of acceptable tolerances for some wing component installations must be achieved within a few hundredths of an inch to avoid introducing unacceptable stall behavior, such as a stall occurring before stick shaker or stick pusher activation, an uncommanded roll through 360°, spin entry, or a combination of these behaviors.

In both stall test flight accidents, the flight crews were line pilots for the respective operators, and each crew was unprepared to successfully remediate the adverse stall behavior they encountered during the flight.

The NTSB is concerned that flight crews and airplane owners and operators may not understand that the training and experience needed to safely perform a stall test flight in certain Hawker airplanes exceeds that which is typically provided to operational line pilots.

The NTSB is also concerned that flight crews may not fully understand that the wing design is sensitive. Visually imperceptible defects in wing component installation or condition, as well as light wing ice or frost accretion, can result in adverse stall behavior and a loss of airplane control.

Encounters with Adverse Stall Behavior

The most recent accident involved a Hawker 800XP airplane, XA-JMR, that crashed on October 16, 2025, near Bath Township, Michigan. The other involved a Hawker 900XP airplane, N900VA, that crashed near Westwater, Utah, on February 7, 2024.

In both of these accidents, each flight crew lost control of the airplane after it exhibited adverse stall behavior. In the case of the Hawker 900XP, this included stalling concurrent with the stick shaker and rolling through 360° multiple times in a near-vertical descent profile consistent with a flat spin. Although the NTSB found that the Hawker 900XP flight crew did not properly ensure that the airplane’s wings were free of ice before conducting the stall test, the circumstances of the accident highlight the airplane control challenges that flight crews performing stall tests may face when adverse stall behavior is encountered, regardless of the reason for the behavior.

Although the NTSB’s investigation of the Hawker 800XP accident is ongoing, the descent profile of that airplane was similar, and a preliminary review of the weather in the area does not suggest a structural icing scenario.

The NTSB’s report also discusses a stall test flight incident involving a Corporate Jets Limited BAE 125-800A, a training flight accident involving a Hawker Siddeley HS-125-700A, and two stall test flight events involving a Raytheon Corporate Jets Hawker 800XP and a Hawker 125-800. The incident airplane had frost near the wing root, and the event airplanes had some bent vortex generators that resulted in adverse stall behavior.

Flight Crew Selection and Wing Surface Condition Considerations

In its report, the NTSB raises concerns about the need for manufacturer-authorized pilot training and experience qualification criteria and stall test plans for performing postmaintenance stall test flights. Currently, neither are clearly defined.

Further, the NTSB raises concerns about the adequacy of the available information about the adverse effects of certain visually imperceptible wing component installation or condition defects or light wing ice or frost contamination on airplane stall behavior.

The NTSB has issued urgent safety recommendations to Textron Aviation Inc. and the FAA to address these issues. However, the NTSB believes that, until those actions are completed, increased owner, operator, and pilot awareness of the following can help prevent future accidents:

• The flight crews tasked to perform manufacturer-required postmaintenance stall test flights in certain Hawker airplanes may encounter adverse stall behavior or unacceptable stall characteristics, such as a stall occurring before stick shaker or stick pusher activation, an uncommanded roll through 360°, spin entry, or a combination of these behaviors.
• The flight crew training and experience needed to safely perform a stall test flight in certain Hawker airplanes exceeds that which is typically provided to operational line pilots.
• Due to the wing design of certain Hawker airplanes, certain visually imperceptible wing component installation or condition defects or light wing ice or frost accretion can result in adverse stall behavior, such as a stall occurring before stick shaker or stick pusher activation, an uncommanded roll through 360°, spin entry, or a combination of these behaviors.

As a result, the NTSB has issued an urgent safety recommendation to the National Business Aviation Association (NBAA), Safety Recommendation A-26-7, asking the NBAA to inform its members about the circumstances of these accidents and the safety issues identified.

NTSB Reports

NTSB report AIR-26-01, which contains the urgent safety recommendations, and its public docket, case DCA26SR003, can be found at ntsb.gov. The reports and public dockets for the stall test flight accidents and incident, cases ANC26FA002, WPR24FA083, and CHI06IA127, respectively, and the training flight accident, DEN03FA155, can be found using the NTSB’s CAROL Query search tool.