SCREEN

The program screen is divided into four main parts:

1. At the top of the screen you will see an animation of an airplane. There are four aircraft from which to choose: an executive jet powered by two simple turbojet engines, a fighter plane powered by two afterburning turbojets, an airliner powered by four high bypass turbofan engines, and a hypersonic missile powered by a single ramjet engine.
2. The left side of the screen presents problems for you to solve. The problems involve either the aircraft range, weight, or the motion of the aircraft as predicted by Newton's Second Law of motion. The problems are presented to you as word problems. The blue buttons in the middle of the left screen are used to set problem type, the difficulty level, and to set new problem conditions. The white choice buttons on the left are used to determine the program mode, the answer type, and the units. (See the explanation given below.)
3. Below the airplane animation on the right side of the screen are some gauges and text boxes that describe the flight and engine conditions. You will need this information to answer the questions that are presented to you on the left side of the screen. You can answer the problems either by typing in an answer or by clicking on a multiple choice button. You can change your answer as often as you want; when you think you have the final answer, press the red "Submit Answer" button to send the information to the computer.
4. At the bottom of the screen, if you choose Learn or Exam Mode, the program will store and display the questions and your answers. This screen keeps track of the numbers of right and wrong answers, allowing you to look for trends and determine a need for additional help with certain problems.
   

OPTIONS: Aircraft Type, Problem Type, Answer Type, Program Mode, Units

1. When you select an Aircraft, you will notice that the fighter plane can travel very fast but not very far, while the airliner can travel a long distance but not very fast.
2. The blue buttons allow you to select a New problem, the difficulty of the problem, either Easy or Hard, the Problem Type, and the Specific Problem at the top of the text box. There are three problem types: Range, Weight. and Motion.
   1. The range problems involve solving a rate equation (rate X time = distance).
   2. The weight problems involve determining the mass of the aircraft from the presented weight.
   3. The motion problems involve solving for acceleration, velocity, distance, or time when given the weight of the aircraft and the thrust of the engines. (In this group of problems, assume that drag is zero and that thrust and weight are constant. This will, however, give some very unrealistic answers since drag itself changes with the velocity squared).

   For some problems, you may have to perform several intermediate calculations to get the final answer. Use a calculator if necessary. If the Easy problem type is chosen, the program will provide you with intermediate information in the statement of the problem. If the Hard problem type is selected, you must perform all calculations. The equations needed to solve the problems are given on summary slides for range , weight, and motion (Newton's Second Law) at The Beginner's Guide to Propulsion on the World Wide Web. The hypersonic missile problems are particularly difficult because the missile is in motion when the additional thrust is applied. Be very careful with the requested units; some information is given in miles per hour, but the requested output is in feet per second.

3. For the Answer type, you can choose Multiple Choice or Type-ins.
   1. If you select Multiple Choice answers, the computer will give you hints about incorrect answers. If you multiplied when you should have divided, the program will note a "Probable Math Error." If you used the wrong variables to solve the equation, the program will note a "Probable Input Error." You and your teacher can use this information to identify areas for additional work. If you select Multiple Choice answers, you can change your answer until you press the "Submit Answer" button. If you get the right answer you will see a blue arrow -----> next to your choice. If the answer is incorrect, a red X will appear. When you get the right answer, you must push the "New" problem button to start another problem. Or you can use the blue buttons to select a different type of question altogether.
   2. If you select Type-ins, simply key in your answer in the space provided and press the "Submit Answer" button. You will be told if you are right or wrong and given a hint for solving the problem.
4. Program Mode allows three choices: Play, Learn, or Exam Mode. In Play Mode, none of your answers are recorded at the bottom of the screen, and you get three tries to answer any question. In Learn Mode, your answers are recorded and you get three tries. In Exam Mode, your answers are recorded and you get only one try on each question.
5. The problems can be presented to you in either metric or English Units.

Good luck!