What is a borescope inspection report?
Borescopes are visual inspection tools used in areas of an aircraft that are hard to access because they are narrow or small, such as engines and turbines.Using a borescope saves a lot of time and resources, since the alternative is taking apart complex equipment like an engine entirely.
A borescope has a long narrow tube with a camera attached to one end. The borescope inspection procedure involves inserting a tube into the narrow space, when the borescope sends video footage to the monitor on its body. Some borescopes have extra attachments like light sources, infrared scanners, and fiber optics.
A borescope inspection report contains all the processes, findings, and decisions that took place during a given inspection. It also contains significant images that were taken to show the general condition of the aircraft engine.
Table of contents:
1. What is a model borescope inspection procedure?
2. Typical defects found during borescope inspection procedures
3. A digital borescope inspection procedure
What is a model borescope inspection procedure?
There are four general stages of a borescope inspection. These are based on the FAA’s requirements.
1. Initiate the inspection
The first portion of a borescope inspection procedure is initiating the inspection. This means carefully planning the inspection task, including considering the access points and proper borescope selection.
Using the right borescope will greatly affect the accuracy of your borescope inspection report, since different aircraft engines have different builds and access points. When selecting the right borescope, consider the points below:
- Access opening inside diameter – Knowing the smallest diameter of the access point will ensure that the borescope camera can easily pass through the access point.
- Travel path geometry – Knowing the travel path shape will help decide whether to use a straight or curved borescope. This also determines if there is a need to use a guide tube.
- Borescope length – Knowing how far the inspection point is from the access point helps choose the right length of borescope. Review the plans and structure of the engine. Also, the longer the borescope length is, the harder it is to control.
- Resolution – Higher resolution means more details, which means better inspection results. Also, depending on the inspection level and requirements, high-resolution images might be needed.
- Type of documentation – Again, depending on the inspection level and requirements, images might not be enough. As such, some instances might require video recording capabilities.
2. Access the inspection task
The second phase of a borescope inspection is accessing and preparing the working area. This is affects the inspector’s motivation, decision-making, and interpreting ability.
There are two types of access: primary access and secondary access. Primary access refers to the act of going to the inspection point whereas secondary access refers to the act of actually performing the inspection.
For both of these acts, mobility should be unhindered and uncomfortable positions should be avoided. Safety should also always be a priority. Staging equipment such as stairs, scaffolding, and platforms should always be used to prevent accidents and protective measures against sharp corners and edges should be implemented. All of these preparations should be documented in the borescope inspection report.
3. Search for indications
During the actual inspection of the aircraft, the goal is to search for “indications” or any unusual physical defects. All these “indications” need to be properly documented in the inspection report and classified according to the type of defect, blade count, and defect location. It is important not to rely on memory when searching for indications. Blade counting can be done more easily using software to help record and mark defects. But it can also be done manually by logging data into a notebook.
To effectively search for indications, inspectors should continuously ask themselves “What is wrong with this picture?” while looking for any abnormalities. It is also recommended to adjust light sources and camera angles to get a better view of the area under inspection.
Typical defects found during borescope inspection procedures
There are various types of defects that can be detected through visual inspection. The most common that a borescope inspection is likely to find are:
- Corrosion – Corrosion is an obvious defect caused by the electrochemical reaction of the metal with its environment, such as oxidation. Corrosion is not always easily detectable in aircraft engines.
- Discoloration – Discoloration can be caused by various factors such as burns, manufacturing issues, and corrosion.
- Cracks – Cracks can be caused by fatigue or impacts caused by external elements. Large cracks can be easily noticeable, but for hairline cracks, you’ll need a borescope with special attachments.
- Surface finishes – Typically, problems with surface finishes on the aircraft engine are caused during the manufacturing process. These problems include blemishes, pits, and granules.
A digital borescope inspection procedure
Performing safety and quality inspections on the go is easy with digital borescope inspection checklists. With Lumiform, inspect aircraft from your smartphone or tablet – online or offline – and easily create a full report without forgetting anything. Create checklists for your borescope inspection and easily collect data in the field to ensure equipment longevity.
Using Lumiform for digital inspections also gets you:
- Over 12,000 ready-made templates to choose from, so that you can go digital in the blink of an eye.
- A flexible form builder that helps you convert any paper-based borescope inspection into a digital one quickly.
- An easy-to-use mobile app, you and your inspectors can perform borescope inspections efficiently.
- Comprehensive and automated analyses that help you uncover threats effectively, and thus facilitate continuous process improvement.
