Practicing with a flight simulator

Practicing with a flight simulator such as FMS or Realflight can make a big difference in your skills advancement. For beginners it can make the difference between crashing on your first flight and NOT crashing on your first flight. For experts, it can improve your precision and reactions with more advanced maneuvers and teach you how to "feel out" a new plane much faster.

These are not necessarily in order, but they do get harder as you go down the list. The first few should be done with 3-channels planes if you're new, and 4-channel planes as you get better... the last ones will require 4-channel planes.


1. Taking off in a straight line without stalling - practice this with an under-powered plane that stalls easily. Try it with different wind directions and try to do it with the plane out of trim.

2. Left turns and right turns - they are different. Try these coming toward you as much as possible. Learn to do it without losing altitude. Try big turns first and then make them sharper until you can do it in all 4 directions without losing altitude. Do this until it is second nature - until you don't have to think about it. Practice this with 3-channels first, then go up to 4-channel planes where you'll "bank and yank" - rolling and pulling up to make the turn. Return to straight and level flight after each turn. Then when you are good at that, practice linking your turns without flying level in between each turn.

3. Landings - same as take-offs - try it with different wind settings and try it with the plane out of trim. Try landing with an over-powered plane that glides well, and then try it with an under-powered plane that stalls easily and needs to be landed at a higher speed. The Pitts in FMS is good for this... you can't just cut the throttle and let it float down like a Slow Stick.

4. Practice flying a pre-determined flight path beginning with a take-off and ending with a landing. The take-off and landing should be in the same direction. Try it with different wind settings. Try figure-8 patterns and left-hand and right-hand circles. One of the mistakes I made when I was learning was to always fly left-hand patterns - this became a small problem at the club one day when the wind was blowing the other way... I had to fly a right-hand pattern, and it actually did mess up my thinking a bit. Practice both directions equally.

5. Practice simple loops - get some airspeed and pull full up elevator and stop when the plane recovers back to level flight. Gradually make your loops bigger and learn to reduce the throttle at the top of the loop to make a more perfect circle. Some planes can not do a big loop - learn to recognize this. Learn to recognize when your loop is not going to make it, and figure out how to "roll out" of a loop that is not going to end well. You will know what I mean when you practice it.

6. Practice recovering from trouble. Stall the plane and recover. Put it into a spin and recover. Get a 3-channel plane on its side and recover. Have someone move your trims to a weird spot and practice taking off and trimming the plane and then landing. If you have RealFlight, you can program it to simulate problems with the plane - this is very helpful, since problems during flight do occur and this feature can help you learn to save a plane that is not functioning correctly.

(Those are the basics - for the rest of these you will want a 4-channel plane)

7. Try simple rolls using ailerons only - point the nose slightly up and roll the plane all the way over and back to upright and level flight - then get back into the pre-determined flight pattern. Your rolls will make an arcing path (gaining and losing altitude), but this is ok at this point.


8. Fly inverted in a straight line for short periods. Roll the plane upside-down and use up-stick to hold it level. Then roll back to upright straight and level flight.

9. Practice perfectly straight and level flight. This is harder than it sounds. Learn what a plane looks like when it's flying level. If you are seeing the wing edge-on, you are not level. A plane that is higher than your head and flying level will show you a little bit of the bottom of the wing. Learn what this looks like. At this point, you will be practicing more precision flight, where before, you were just noodling around getting your reactions straight. Try this inverted as well, and in various wind conditions. Learn to use the rudder to keep your plane tracking straight.

10. Practice rolls using the rudder to keep the plane tracking level during the portion of the roll when it's on its side. For a left-hand roll, the sequence is this: holding left aileron through the whole roll, first apply right rudder as the plane gets on its side, then apply a bit of down elevator when the plane is inverted, then a little left rudder as the plane is on the other side, then return to level flight. You may want to break this up into a 4-point roll to slow things down, but eventually you should be able to do a smooth roll without stopping and without gaining or losing altitude.

11. Practice flying the pattern inverted. Learn to make turns when you are inverted, using the rudder and ailerons to bank and turn. Learn to control the throttle and use down elevator to keep the plane from losing altitude.

12. Practice knife-edge flight. Use the rudder to hold altitude and the elevator to make turns. Try to fly figure-8 patterns and try rolling from side to side. Practice entering the knife-edge from upright and inverted positions. When entering the knife-edge from upright flight, you will "cross the sticks" with the rudder and ailerons, but when you enter from inverted, your aileron and rudder direction will be the same. Do this until it becomes instinct. Learn the exact right moment to apply the rudder... too soon and your plane will not track straight... too late and you'll lose altitude. Try to slow down the knife-edge flight until you enter a knife-edge "harrier" maneuver. This is one of the easiest of the "3D" moves to do. Learn to control the throttle to hold the plane in the knife-edge at about a 45-degree angle, still moving to the side, but very slowly. This will help you to learn to hover later.

13. Try precision "pattern flying" - this involves doing loops and rolls and combinations of those while making very precise straight lines. You will be drawing patterns in the air, with smooth radii and straight lines. This is a competitive style of flying, and it is difficult, but it allows you to judge your progress because it is very easy to see when you've gone off line. The basic pattern maneuvers for the Beginner (or Sportsman) level of competition are listed here. Learn to do these moves perfectly. If you have Realflight, you can record your flight and play it back later. I find this very helpful in judging how well I did. As you progress, look up the advanced pattern sequences and practice some of the more advanced moves. Pattern flying is a never-ending challenge - you can never be perfect.


14. Practice harriers and other "3D" moves. There are entire articles about this. When you get to this point, you will know what to do. Learn to hover and harrier, and learn the flat spins and other fun moves. In my opinion, this is the pinnacle of precision flying. If you can do this stuff, get the hell off the simulator and go out and fly already. Or if you have Realflight, go online and find me and show me your stuff!

This by no means is a set order of learning. You can practice the advanced stuff in any order you want. This list is not intended to be a step-by-step lesson plan, but is more intended to help you identify specific areas where the simulator practice can help you improve your skills for real-life flying. Most of all, have fun!

Over and out!
Jasmine

Energy usage and motors and propellers

(this is in response to this thread - questions about props and pitch and diameter and so on)

You're correct so far about props, but it's fairly complicated. Here's the long explanation...

We know that energy can not be destroyed, right? So that means that any electricity you send into a motor will either be turned into kinetic energy by spinning the prop, or heat, which is the enemy of metal parts. That's beside the point really, but keep it in the back of your mind for when I talk about efficiency, because the losses due to lowered efficiency show up as heat, usually in the motor wires, some in the bearings too.

First some definitions:
A Newton is a unit of force - it is the force required to accelerate a one kilogram mass by 1 meter per second squared. So, if you apply 1 Newton of force to a 1 kilogram mass for one second, it's final speed will be 1 meter per second faster than it was before you started applying the force.

A Joule is a unit of energy - it is the amount of energy expended by a 1 Newton force over a distance of 1 meter.

A Watt is a unit of the rate of energy usage - it is one Joule per second.

The units of electricity usage were set up deliberately such that 1 volt times 1 amp will be one watt of energy usage - 1 Joule per second.

So, if you have a 1 kilogram airplane, and you want it to accelerate at 1 meter per second per second, you need to have one watt of power. If there was no drag or gravity or anything, your theoretical plane would be going 1 meter per second after 1 second of time, and speed would be 2 meters per second after 2 seconds of time, and so on.

When you measure the wattage of your power system, this is exactly what it means... so for example, my Brio draws 250 watts, and it weighs about 2 kilograms (4.4 pounds). This means that if all the energy put out by the battery were used to accelerate the plane, it would have acceleration of 125 meters per second per second. Obviously, the Brio doesn't go that fast... so there is some huge losses going on there.

The losses are due to the efficiency of the motor (about 85%), giving approximately 40 watts lost as heat in the motor. If you've ever put your hand on a 40 watt light bulb, you know that's a lot of heat. The rest of the losses are due to the drag of the plane and the propeller itself. Propellers are not very efficient - anywhere from 10% to 50% loss. On small planes at normal speeds it's closer to 50% losses. So now my Brio has about 100 watts remaining, and that is being turned into kinetic energy...

However, it is not all turned into forward momentum... some of it is lost to drag, and some of it is turned into lift by the wing. An airplane must consistently overcome the force of gravity time its own weight. That is 19.8 Newtons for my 2-kilo plane... every second - meaning I need 20 watts worth of lift just to stay in the air. Wings are horribly inefficient, so I'm wasting a ton of energy just turning forward momentum into lift.

It was a long journey, but here's where the propeller comes in...

A propeller has two measurements... diameter and pitch. Diameter is obviously just the length of the thing. Pitch is a little more complicated... it is defined as the linear distance that the propeller would move if it was turned one revolution in a thick fluid (air is not a thick fluid). A 10x6 prop will move 6 inches forward in one revolution, but a 50x6 prop will also move 6 inches forward in one revolution, but it will use a lot more energy - but it will use it more efficiently.

Thrust is the acceleration force of the propeller - it is the amount of Newtons that the prop creates. Multiply that by a distance, and you have Newtons times meters, and remember, that is the definition of a Joule. Multiply that by a unit of time, and you have Joules times seconds, which was the definition of a Watt. So, to bring that full circle, the Watts used by the prop are directly related to the thrust it creates, bigger diameter props use more Watts, have more Newtons, and we call that more thrust. The 50x6 propeller is going to have more of that, even though the pitch is still the same as the 10x6.

I know that was a convoluted explanation, and for those who don't want to know why things are the way they are, it's simple enough to say what Sir Raleigh said... more diameter, more thrust, even if the pitch is the same.

Pitch is indirectly related to speed, but it's fairly complicated. If the RPM is kept the same, more pitch will result in both more thrust and more speed, because the speed if there was no slipping or drag or anything, would be the pitch times the RPM... it would be 6 inches times the number of rotations, divided by a time period, and a distance divided by a time period is the definition of speed. It is not that simple though, and more pitch will only create more speed if you can keep the RPM the same. Due to losses from efficiency problems and drag and lift and so on, there is never a direct relationship between pitch and speed. Speed comes from thrust, so if you want the plane to go faster, you need more thrust (more Newtons of force). In practice, what we see is that increasing the pitch gives more force, and we realize an increase in speed, but it is not that simple. You only get more speed (which requires more thrust) when you can keep the RPM the same. With electric motors, the RPM will drop a little when you increase the pitch, but not by much, so we do see more speed.

I know that is more than what you wanted to hear, but these things are never simple. I just hope that if you could stand to read that all, you'll understand more why we have to measure things. It is not a guarantee that increasing the pitch will give more speed, but if you increase the diameter, you will have more energy usage, and that always translates to more power, more speed, more everything... but it also means you may overwork the motor.

SIG Riser

This is my SIG Riser - it was fun to build and I covered it myself. It is a 2 meter glider, but I'm going to put a motor on the front. This is the first plane that I built and covered myself, and I think it came out pretty good!