So, you’ve decided to become a licenced engineer, and someone has mentioned that you need to complete a Cap 741 logbook. But what exactly is it? How do you fill it out? And how can you tell when it’s complete enough to submit to the CAA for review? All these questions, and more, will be answered in this article. Let’s dive in!
This guide is designed to help you make the right decisions when it comes to filling out your logbook. There’s nothing worse than reaching the five-year mark, only to discover that you've filled it out incorrectly and a licencing officer penalises you for it.
‍
What is a CAP 741 logbook?
For the CAA to review your live aircraft work experience, you must be able to demonstrate a certain amount of aircraft maintenance experience.
This experience is captured in a document published by the CAA called the CAP 741 logbook. Rather than submitting your a pile of A4 papers—like what a child might bring home from school—the CAA requires your experience to be structured in a way that can be easily reviewed.
A CAP 741 logbook is where you record all maintenance carried out on live aircraft in a structured manner, allowing you to demonstrate your experience on various systems of live aircraft. For example, you can show how much involvement you’ve had with hydraulic systems, flight controls, and other components.
‍
How to fill out a CAP 741 logbook?
The CAP 741 logbook is broken down into the following sections:
- Section 1.2: Personal data
- ‍Section 1.3: Employment record
- ‍Section 2.1: Basic Skills
- Section 3.1: Maintenance experience
- Section 3.2: Typical maintenance tasks
- Section 3.3: Glossary
You can download a copy of the CAP 741 from the CAA website via this link. There’s no need to go over how to fill out your personal data and employment record section, so we won’t waste any time on that. Let’s dive straight into the Basic Skills section.
‍
Section 2.1: Basic skills
Before we delve into this section, it's important to note that the CAA requires the following three levels of maintenance experience on live aircraft before issuing a licence:
- 2 years after completing a Part 147 apprenticeship
- 3 years if you have experience in a relevant engineering field
- 5 years if you have no previous maintenance or relevant engineering experience
The Basic Skills section is primarily aimed at those in the first category, where only two years of maintenance experience are required before submission.
During your Part 147 apprenticeship, you should aim to have your instructors sign off the sections within the Basic Skills part of the logbook to confirm that you have completed the necessary hand skills training.
If you are submitting your logbook with 3 or 5 years of maintenance experience on live aircraft and have not completed a Part 147 apprenticeship, you do not need to fill out this section.
‍
Section 2.1: Maintenance experience
This section of the logbook is where you record your experience with live aircraft. The PDF provides one page for each entry, which you can print multiple times to complete a separate page for each ATA chapter.
The most important thing to keep in mind is that many people filling out these logbooks will be working on multiple aircraft types simultaneously. As a result, you would typically start a section for each aircraft, utilising the ATA chapters for organisation.
However, when a CAA surveyor reviews the logbook, they are looking for a certain amount of maintenance experience within each specific system. For instance, if they require 20 tasks within Chapter 32 (landing gear), covering a range of tasks from troubleshooting and removals to inspections and operational tests, they won’t be pleased if those 20 tasks are scattered across multiple sections—such as 5 tasks in Chapter 32 for an A320, 5 tasks in Chapter 32 for a Boeing 777, and another 10 tasks for an A380.
You need to consider the reviewer’s perspective. The easier you make it for them to assess your experience, the more likely it is that your licence application will be approved. The best approach is to organise your ATA chapters from Ch5 to Ch99 (military systems can go up to Ch99), in order, regardless of the aircraft type. You can then have separate pages for different aircraft types as you progress through the chapters.
Now that we've discussed how to structure the logbook, let's move on to filling out the individual tasks. Let’s say you are replacing an aileron power control unit (PCU). The quickest way to complete this task would be to simply state, "Aileron PCU replaced." While this certainly ticks the box, it fails to demonstrate the full scope of the task and misses the opportunity to show the depth of your involvement.
Components on aircraft are rarely replaced without reason—typically, they are life-expired or faulty. Most of the time, there’s a story to tell behind the replacement. Let’s explore how to tell that story in your logbook, which will help demonstrate to the licencing officer that you have a comprehensive understanding of the aircraft you are maintaining.
A smarter way to present this task in your logbook would be as follows:
- During a routine operational test, it was noted that the RH outboard aileron PCU was showing amber on the EICAS display. Troubleshooting was initiated.
- Access panel "XXX" was removed and refitted to provide access.
- Troubleshooting was carried out, including wiring checks between the primary flight control computer and the aileron PCU, with good continuity found between the two.
- The RH outboard aileron PCU was transposed with the RH inboard aileron PCU, and the fault followed. The PCU was confirmed faulty and required replacement.
- The aileron PCU was replaced.
- A full operational test of the aileron system was carried out, with no faults noted. Task was closed.
If a licencing officer were to see this level of detail, it would demonstrate that the engineer is more in tune with the maintenance process and is not simply replacing components without fully understanding the underlying reasons.
Of course, the reason for maintenance will vary from case to case, but there is always likely to be a valid justification for the work being carried out. Use all the available information when filling out your logbook.
This approach helps to show that you are actively engaged, learning within your role, and ready to take on a licenced position within the industry.
Regarding repetitive tasks, such as panel removal or installation, these should only be recorded a few times to show you have completed them, then not repeated in later sections. If, upon review, your logbook contains 50% panel removals, installations, or repetitive refuels, it is likely to be rejected.
What is the CAA looking for?
This is where Section 3.2 of the logbook comes into play. Although this section doesn’t provide specific guidance on its purpose, it is, in fact, the most important part of your logbook. Think of it as a guide to filling out your logbook.
The list in Section 3.2 becomes more relevant when you begin filling out your OJT later on. It provides a comprehensive list of all tasks to be completed during the initial OJT for your first type. According to the regulations, 50% of this list should be completed before submitting your OJT.
Now, let’s look at one of the chapters mentioned in Section 3.2.
Communications – chapter 23:
- Replace VHF comm unit
- Replace VHF comm unit
- Replace HF comm unit
- Replace existing antenna
- Replace static discharge wick
- Check operation of radios
- Perform antenna VSWR check
- Perform Selcal op check
- Perform op check of passenger address system
- Functional check of audio integration system
- Repair co-axial cable
- Troubleshoot faulty system.
What you’ll notice straight away throughout Section 3.2 is that most chapters end with "troubleshoot faulty system." This is of paramount importance, as the CAA is looking for engineers who are not only skilled at servicing items and replacing components but also capable of identifying faults in systems that aren’t operating properly.
Each chapter of your CAP 741 logbook should, within reason, include at least 3-4 instances of troubleshooting to demonstrate that you have a broader understanding of how various LRUs (Line Replaceable Units) within a system communicate and how to identify faults in general.
You’ll also notice that each chapter expects a wide range of tasks, from removal and installation to operational checks (op checks) and functional checks. It’s important to distinguish between the two: an operational check typically involves a quick verification to ensure the system is working correctly, while a functional check is more in-depth, ensuring the system’s overall health by checking additional parameters.
In complex avionics systems, a functional check might involve examining bit data to confirm that each computer is outputting the correct data. On the other hand, an operational check could simply involve verifying that when you push the control column forward, the elevators move down.
A licenced engineer must be comfortable carrying out removals, installations, servicing, operational checks, functional checks, and troubleshooting on any system. While you may not be familiar with every subsystem on board, your logbook should demonstrate the ability to work through and troubleshoot unfamiliar systems.
To recap, each chapter within your logbook should include a range of component replacements, multiple operational checks, and a few functional checks. Aim to incorporate 3-4 troubleshooting tasks per chapter. Additionally, if any specialist repairs have been carried out, such as coaxial repairs on specific systems, be sure to include them.
‍
Top Tip!
When carrying out certain tasks, you may need to use specialist equipment, such as air data test sets or ELT system test sets (e.g., IFR 4000 or 6000 which are used for transponder tests). Be sure to mention the use of these tools when filling out your logbook. If you plan to extend your licence from B1 to B2 in the future, these are the kinds of details a surveyor will be looking for.
Similarly, if you’re moving from B2 to B1, they’ll be looking for additional details like dye penetrant inspections (even if you only shadowed an NDT engineer for the day—be sure to include this in your logbook) or the use of borescope equipment for internal engine inspections.
‍
Section 3.3: Glossary
This section covers the various abbreviations used throughout the logbook. While it's worth browsing through, there's no need to focus too heavily on it, as most manufacturers use their own abbreviations, which you’ll become familiar with during your first type course.
‍
Conclusion
In conclusion, filling out your CAP 741 logbook correctly is crucial for a smooth licencing process. By following the steps outlined in this guide and paying attention to detail, you'll ensure that your logbook accurately reflects your experience. Proper documentation will not only help you avoid penalties but also demonstrate your competence as a skilled engineer.
Start early, stay organised, and always aim for clarity and depth in your entries to set yourself up for success in the licencing process.