Part 91 aircraft must meet certain maintenance requirements, but these requirements are generally less stringent than those for Part 135 aircraft. Part 135 aircraft are required to undergo more frequent inspections and maintenance, as they are used for commercial operations and carry passengers for hire.
Let’s go a little deeper into what Part 135 aircraft maintenance and inspections look like…
Part 135 aircraft are required to undergo a 100-hour inspection at least every 100 hours of flight time. This inspection is a thorough check of the aircraft’s systems and components to ensure that they are operating properly and safely.
In addition to the 100-hour inspection, Part 135 aircraft are also required to undergo an annual inspection, which is a more comprehensive check of the aircraft’s systems and components. This inspection must be completed within the preceding 12 calendar months.
Other required inspections for Part 135 aircraft include a pre-flight inspection, which must be conducted before each flight to ensure that the aircraft is safe to fly, and a phase inspection, which is a more thorough inspection of specific systems or components of the aircraft. Phase inspections may be required after a certain number of flight hours or landings, or after a specific period of time has passed.
In addition to inspections, Part 135 aircraft must also undergo regular maintenance to ensure that they are operating safely. This may include replacing parts that have reached the end of their service life, performing repairs on systems or components that have failed or are showing signs of wear, and performing routine maintenance tasks such as oil changes and tire rotations.
Overall, the inspections and maintenance requirements for Part 135 aircraft are designed to ensure the safe operation of the aircraft and the safety of its passengers. These requirements are typically more stringent than those for Part 91 aircraft, as Part 135 aircraft are used for commercial operations and carry passengers for hire.