Cessna’s Secondary Seat Stop is a critical safety enhancement for certain single-engine aircraft models, designed to prevent the pilot seat from sliding backward unexpectedly. The system functions similarly to an inertia reel, locking the seat in place during sudden movements. This feature was introduced in response to concerns about seat movement during flight, particularly in the event of turbulence or abrupt maneuvers. Service Bulletin SEB89-2 Revision 2 mandates the installation of the Secondary Seat Stop for specific Cessna models and serial numbers, with compliance required within 400 hours of operation or 12 months. The system is also available as a free kit for affected aircraft and requires careful inspection and maintenance to ensure proper functionality. This article provides a detailed overview of the Secondary Seat Stop, including compliance requirements, installation procedures, and maintenance considerations.
Overview of the Secondary Seat Stop System
The Secondary Seat Stop is an inertia reel system designed to prevent the pilot seat from sliding backward during flight. It operates similarly to a shoulder harness, locking the seat in place when there is rapid backward movement. The system is installed on the seat pin and is connected to a spring-loaded cable. When the seat is moved backward, the reel allows for smooth movement, but if the seat moves quickly or forcefully, the mechanism engages, locking the seat in place.
According to a 2022 webinar by Paul New, the Secondary Seat Stop is an important safety addition to Cessna aircraft. The system is made from plastic housing and is attached to a spring and cable mechanism. The housing is vulnerable to damage, particularly from impacts with other objects under the seat, such as a fire extinguisher. It is recommended that pilots ensure the area beneath the seat is free from objects that could cause damage to the housing.
The Secondary Seat Stop is provided as a free kit for each airframe serial number and does not require a logbook entry to be submitted to Textron as proof of installation. However, the system must be inspected regularly to ensure it is functioning properly and that there is no visible damage to the housing or mechanism.
Compliance Requirements and Service Bulletin SEB89-2 R2
Service Bulletin SEB89-2 Revision 2 mandates the installation of the Secondary Seat Stop for specific Cessna models and serial numbers. The revision updates the credit and compliance sections of the original service bulletin, making compliance mandatory within 400 hours of operation or 12 months. The bulletin provides detailed instructions for compliance, including the required parts and procedures for installation.
The compliance deadline is strict and must be adhered to by the aircraft owner or operator. Failure to comply within the specified timeframe could result in safety risks and potential regulatory issues. The service bulletin is considered an official directive from the manufacturer and must be followed accordingly.
The affected aircraft models and serial numbers are listed in the service bulletin, ensuring that only those aircraft that require the Secondary Seat Stop are subject to the compliance requirements. The service bulletin also outlines the steps necessary to complete the installation and verifies that the system is functioning correctly after installation.
Installation Procedures
The installation of the Secondary Seat Stop involves several key steps that must be followed carefully to ensure proper functionality. The system is designed to be installed on the seat pin and is connected to a spring-loaded cable. The installation process typically requires the removal of the seat pin and the attachment of the Secondary Seat Stop kit.
The installation must be performed by a qualified aircraft mechanic or at a certified maintenance facility. The service bulletin provides detailed instructions for the installation process, including the required tools and materials. The kit includes all necessary components, such as the housing, spring, and cable, and must be assembled according to the manufacturer's specifications.
Once the Secondary Seat Stop is installed, the system must be tested to ensure that it is functioning correctly. This involves checking that the housing is not cracked, that the mechanism engages properly, and that the seat can be moved backward smoothly without resistance. If any issues are detected during testing, the system must be adjusted or replaced accordingly.
Maintenance and Inspection Guidelines
Regular maintenance and inspection of the Secondary Seat Stop are essential to ensure that the system continues to function properly. The plastic housing is particularly vulnerable to damage and must be inspected for cracks or other signs of wear. If any damage is detected, the housing must be replaced immediately to prevent failure of the system.
Pilots are advised to inspect the Secondary Seat Stop as part of their preflight checklist. This includes checking that the housing is intact, that the mechanism is engaging properly, and that there is no visible damage to the system. If any issues are suspected, the aircraft should be inspected by a qualified mechanic as soon as possible.
In addition to regular inspections, the area beneath the seat must be kept clear of objects that could cause damage to the housing. Pilots should avoid placing items such as fire extinguishers or other equipment under the seat, as these can impact the housing and cause damage. The cable and spring mechanism must also be checked for signs of wear or damage and replaced if necessary.
Considerations for Aircraft Operators and Maintenance Facilities
Aircraft operators and maintenance facilities play a key role in ensuring the proper installation and maintenance of the Secondary Seat Stop. Operators must ensure that the system is installed in accordance with the service bulletin and that compliance deadlines are met. This includes coordinating with maintenance facilities to schedule the installation and verifying that the system is functioning correctly after installation.
Maintenance facilities must ensure that they have the necessary tools and expertise to perform the installation and inspection of the Secondary Seat Stop. The service bulletin provides detailed instructions for the installation process, and mechanics must follow these instructions carefully to ensure that the system is installed correctly. In addition, maintenance facilities must be prepared to handle any issues that may arise during the installation or inspection process.
Operators and maintenance facilities must also be aware of the importance of regular inspections and maintenance. The Secondary Seat Stop is a critical safety feature, and any failure of the system could result in serious consequences. Therefore, it is essential that the system is inspected regularly and that any issues are addressed promptly.
Addressing Common Issues and Limitations
The Secondary Seat Stop has been reported to have a few limitations and potential issues that operators and mechanics should be aware of. One of the main concerns is the plastic housing, which can break if it is impacted by objects under the seat. This can lead to failure of the system and must be addressed immediately if any damage is detected.
Another issue is the cable mechanism, which is attached to a spring and must be adjusted properly to ensure smooth operation. If the cable is not adjusted correctly, the system may not engage properly, leading to potential safety risks. Mechanics must ensure that the cable is properly adjusted and that the spring is functioning correctly.
Operators should also be aware that the Secondary Seat Stop is not required for all Cessna models. The system is only mandated for specific models and serial numbers, and operators should verify whether their aircraft is affected before proceeding with installation. In addition, operators should be aware that the system is provided as a free kit and does not require a logbook entry to be submitted to Textron as proof of installation.
Conclusion
The Cessna Secondary Seat Stop is a critical safety enhancement for certain single-engine aircraft models. The system functions as an inertia reel, locking the seat in place during sudden movements and preventing it from sliding backward unexpectedly. Service Bulletin SEB89-2 Revision 2 mandates the installation of the Secondary Seat Stop for specific Cessna models and serial numbers, with compliance required within 400 hours of operation or 12 months. The system is provided as a free kit for affected aircraft and must be installed by a qualified aircraft mechanic or at a certified maintenance facility. Regular inspection and maintenance are essential to ensure that the system continues to function properly and that any potential issues are addressed promptly. Operators and maintenance facilities must be aware of the importance of compliance and the potential limitations of the system to ensure the safety of the aircraft and its occupants.