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How to do KDRs

By Ashley Miller

Congratulations, you passed your CASA exam. What a great result!! Unless you got 100%, you will receive a Knowledge Deficiency Report, or KDR. This report shows the areas of the subject where your knowledge is still lacking, and further study is required.

When I first heard about KDRs, I had just passed my first passed my CPL Aerodynamics exam. I passed with 73%, so there were a few topics covered in my report. Like many students, I had no idea what all the references on the KDR report meant. I didn’t study de-coding at Uni, and felt like I needed a degree to understand it. It even made hieroglyphics look easy. Upon asking my instructor though, they were able to point me in the right direction, and I hope this blog will help you too.


The Civil Aviation Safety Regulations 1998 (CASR) provides regulatory controls over all civil aviation safety. The Manual of Standards, or MOS for short, details technical material which complement the requirements set in the CASR.

The Part 61 MOS supports flight crew licensing regulations and contains:

  • aeronautical knowledge and practical competency standards for Part 61 licences
  • ratings and endorsements
  • standards for Part 64 authorisations
  • all flight test, proficiency check and flight review standards

There are 4 volumes to this MOS and the key one to help with your KDRs is Volume 3. This contains the Aeronautical Knowledge Standards. These standards are used to direct theory training, whether it is self-study or a formal course of training. These standards are used for Flight Crew licensing theory examinations and test candidates on these knowledge standards.

On the back of your KDR is a list of unit numbers and topics. To demonstrate knowledge, you need to write something in your own words to prove you understand each topic. Depending on the subject listed, the response may require one sentence, or a whole page! Each of the items listed will have been covered during your theory classes, and detailed in your textbook, and you can look back over these resources to help build your answer.

For an example, let’s use the following as your KDR:

  • Effect of Weight Part 61 MOS Unit 1.3.2 CADA, 2.5.3 (a)

Click here for the link to the MOS Volume 3 table of contents to begin familiarising yourself with the layout and see if you can find the example listed below.

Locate the Unit 1.3.2 via the table of contents page shown here on the right. If you are using an online version, you can click on the Unit, and it will take you to the list of topics under that unit.

The other number refers to the specific topic.

2.5 refers to Performance Considerations and more specifically 2.5.3 (a) refers to the following;

For your KDR you would then need to explain how the weight and altitude affects (i), (ii), (iii), and (iv) in detail in your own words.

A common mistake students make is simply copying paragraphs from your Bob Tait textbook or from Wikipedia, etc. Your answers will be checked by experienced Instructors and Flight Examiners – and they are not silly. It’s not hard to recognise when a student has done this.

Another common mistake students make is just listing down the Law document reference, or they just paste in a photo of the topic from in the AIP, CAO, etc. That’s not to say you can’t use pictures to help explain things, especially if a graph may help explain the topic, but write the description in your own words. For Performance or the Navigation KDRs using example questions, showing your workings is encouraged. Take-off and Landing charts, weight and balance sheets and even beginning of daylight and end of daylight charts may also be required as part of your response. The idea of writing of the KDR is to demonstrate that you understand the topic and your testing officer may even use your KDRs as part of your pre-test theory, so don’t short-change yourself by just copying from the textbook.

One more thing to note is that some KDRs may have simply 2.5.3 written and you need to write about everything under 2.5.3. If your KDR has 2.5.3 (a) (iv) then only that specific topic needs to be written about.

Going back to my first KDR for Aerodynamics, with a pass and score of 73%, I think I had something like 10 topics to write about. This took forever to write, and it was like a 3000 word essay at approximately 5-6 pages long. I used that as great motivation, I vowed not to simply aim to pass my other exams but pass well to save me from having to write so much for my KDRs again.

KDRs are not always a quick and easy task – for you, or for the person marking them. We encourage our students to get their KDRs done soon after sitting the exam, so the knowledge is still fresh from all that pre-exam study. It also gives us plenty of time to mark them before your flight test.

Should they wish, Flight Examiners can also question you on your KDRs appropriate to the licence you are testing for. Many will accept an instructor’s signature on the KDR as satisfactory, but students should be aware that they may be asked about some of the areas of deficiency, on top of the usual test theory requirements. Don’t think it’s all over once your instructor has signed them off!

If you are working towards a CPL, you will have many exams to sit and KDRs to be written on your aviation journey. I suggest downloading the MOS on to your computer or at least bookmarking the webpage, so you may refer to it when you need to write up your subsequent exam KDRs.

I hope this helps – and remember, if in doubt check with your instructor for guidance.