Once you have passed Air Law and have taken your first solo flight, your instructor will probably begin to brief you on the navigation exercises that you'll soon be flying. At this point it makes sense to read up on the Navigation theoretical material and to prepare for the exam.
The Navigation course covers the essentials of performing calculations such as wind drift, true heading, compass heading and navigation aids such as VOR. It also includes information on map projections and how to calculate distances and times across much larger areas than you will be likely to fly as part of your PPL Course. Much of it is more likely to be relevant if you move on to become a commercial pilot, unless you are planning non-stop trips between Europe to Asia, but nevertheless it is useful to have an awareness of the issues involved so that you are prepared in the future.
The Navigation exam consists of 12 multiple choice questions to be completed in 45 minutes and is possibly the most difficult exam in the course. As the pass mark is 75% it also means you have to get at least 9 questions right. You will need a flight computer (of the slide rule variety) to take into the exam and you'll need to be able to perform some complex calculations on it. These are covered in revision books, and the flight computer should come with a manual as well, but you'll certainly need to practice these before the exam.
Of particular note in the exam, as with many multiple choice exams, keep a careful eye on potential pitfalls such as mixing up nautical miles and kilometres as one of the available answers will often be something that may appear correct at a glance but is designed to test your attention to detail as much as your ability to calculate.
The PPL Tutor exam app provides test questions along very similar lines to those that you'll encounter in the real exam and there's no better preparation available. To help you with using the flight computer, we have produced a Navigation Training application (currently only available on iOS) which contains a simulated flight computer and can provide you with an unlimited set of problems from simple calculations such as time and distance conversions through to computation of wind drift and in-flight heading.
You can try the PPL Navigation Trainer app for free and get a feel for whether you will find it useful and, as with the other subjects, we're confident that once you've tried the free Air Law exams and content in the PPL Exam Tutor application you'll be convinced of the value of unlock Navigation and Radio Aids as well as the other seven subjects.