What is SPL on Boeing 737? (Splice List)

The Splice List, also known as SPL, plays a crucial role in the maintenance and repair of Boeing 737 aircraft. It is a comprehensive document that outlines all the necessary procedures and guidelines for dealing with splices on various parts of the aircraft. Splices are essentially joints or connections between two different components, such as wing skins, fuselage sections, and stringers.

Given the critical nature of splices, it is imperative to have a reliable and systematic approach to their inspection, repair, and replacement. That’s where the Splice List comes into play. It serves as a comprehensive reference material for maintenance personnel, ensuring that splices are handled correctly and in accordance with the manufacturer’s instructions.

Let’s dive deeper into the significance of Splice Lists on Boeing 737 aircraft and understand how they contribute to the overall safety and reliability of these iconic airplanes.

Importance of Splice List in Boeing 737 Maintenance

The Splice List is a vital component of the maintenance program for Boeing 737 aircraft. It provides detailed information on splices, including their location, type, and necessary repair procedures. By following the guidelines outlined in the Splice List, maintenance personnel can ensure that splices are inspected, repaired, or replaced using the correct techniques and materials, thereby maintaining the structural integrity of the aircraft.

One of the key advantages of utilizing the Splice List is that it offers a standardized approach to splice maintenance. Regardless of the specific model or variant of the Boeing 737, the Splice List provides a comprehensive set of instructions that are applicable to all aircraft within the family. This uniformity ensures consistency in maintenance practices and reduces the risk of errors or oversights.

Another crucial aspect of the Splice List is its focus on safety and compliance. The document is regularly updated to incorporate any revisions or findings from manufacturers, regulatory authorities, and industry best practices. This ensures that maintenance personnel have access to the most up-to-date information and can perform maintenance tasks in line with the latest standards and requirements.

To exemplify the importance of the Splice List, let’s take a closer look at a specific splice scenario on the Boeing 737:

Understanding the Wing Skin Splice on Boeing 737

One critical splice area on the Boeing 737 is the wing skin splice. The wing skins are large panels that cover the external surface of the wings, providing structural support and aerodynamic smoothness. These skins are generally made from aluminum or composite materials, and during the production process, they are joined together using splices.

The Splice List provides detailed instructions for inspecting and repairing wing skin splices. It specifies the location of the splices along the wing, the type of splice used, and the necessary procedures for inspection and repair. For instance, it may prescribe techniques such as non-destructive testing (NDT) methods like ultrasonic or eddy current inspections to identify any potential damage or defects.

Moreover, the Splice List also outlines the repair procedures to address any identified issues. This could involve replacing damaged sections of the splice, applying appropriate adhesives or fasteners, and conducting follow-up inspections to verify proper repair completion.

By strictly adhering to the guidelines provided in the Splice List, maintenance personnel can ensure that the wing skin splices on the Boeing 737 are maintained at the highest levels of safety and reliability. This, in turn, contributes to the overall structural integrity of the aircraft and enhances its operational performance.


The Splice List, or SPL, is an indispensable tool for the maintenance and repair of Boeing 737 aircraft. It provides meticulous guidelines for inspecting, repairing, and replacing splices, ensuring the structural integrity and safety of these airplanes. By following the instructions outlined in the Splice List, maintenance personnel can perform their tasks effectively and in compliance with the latest industry standards.

Whether it’s the wing skin splices or any other joints on the aircraft, the Splice List serves as a valuable resource, guiding maintenance personnel in their quest to keep Boeing 737 aircraft operating at their best. It is a testament to the meticulous approach to safety and reliability that underpins the aviation industry.

The Splice List is just one example of the many meticulous procedures and guidelines that ensure the longevity and safety of Boeing 737 aircraft. With the continuous advancements and updates in aviation technology, maintenance practices are continuously evolving to meet the ever-increasing demands for safety and efficiency. The Splice List, along with other comprehensive documentation and professional expertise, plays a crucial role in delivering reliable and safe air transportation.

For More: What is EPR on Boeing 737? (Engine Pressure Ratio)