Friday 30 September 2011

Controlling a helicopter



 
Controlling a Helicopter

Helicopters require a completely different method of control than airplanes and are much harder to master. Flying a helicopter requires constant concentration by the pilot, and a near-continuous flow of control corrections.
A conventional helicopter has its main rotor above the fuselage which consists of 2 or more rotor blades extending out from a central rotor head, or hub, assembly.
The primary component is the swash plate, located at the base of the rotor head. This swash plate consists of one non-revolving disc and one revolving disc mounted directly on top. The swash plate is connected to the cockpit control sticks and can be made to tilt in any direction, according to the cyclic stick movement made by the pilot, or moved up and down according to the collective lever movement.
But first, to explain how the main rotor blades are moved by the pilot to control the movement of the helicopter, we need to understand pitch.

The basics of pitch

Each rotor blade has an airfoil profile similar to that of an airplane wing, and as the blades rotate through the air they generate lift in exactly the same way as an airplane wing does [read about that here]. The amount of lift generated is determined by the pitch angle (and speed) of each rotor blade as it moves through the air. Pitch angle is known as the Angle of Attack when the rotors are in motion, as shown below:

This pitch angle of the blades is controlled in two ways - collective and cyclic.


Collective control

The collective control is made by moving a lever that rises up from the cockpit floor to the left of the pilot's seat, which in turn raises or lowers the swash plate on the main rotor shaft, without tilting it.

This lever only moves up and down and corresponds directly to the desired movement of the helicopter; lifting the lever will result in the helicopter rising while lowering it will cause the helicopter to sink. At the end of the collective lever is the throttle control, explained further down the page.

As the swash plate rises or falls, so it changes the pitch of all rotor blades at the same time and to the same degree. Because all blades are changing pitch together, or 'collectively', the change in lift remains constant throughout every full rotation of the blades. Therefore, there is no tendency for the helicopter to move in any direction other than straight up or down.
The illustrations below show the effect of raising the collective control on the swash plate and rotor blades. The connecting rods run from the swash plate to the leading edge of the rotor blades; as the plate rises or falls, so all blades are tilted exactly the same way and amount.
Of course, real rotor head systems are far more complicated than this picture shows, but the basics are the same.



Cyclic control

The cyclic control is made by moving the control stick that rises up from the cockpit floor between the pilot's knees, and can be moved in all directions other than up and down.
Like the collective control, these cyclic stick movements correspond to the directional movement of the helicopter; moving the cyclic stick forward makes the helicopter fly forwards while bringing the stick back slows the helicopter and even makes it fly backwards. Moving the stick to the left or right makes the helicopter roll and turn in these directions.
The cyclic control works by tilting the swash plate and increasing the pitch angle of a rotor blade at a given point in the rotation, while decreasing the angle when the blade has spun through 180 degrees.

As the pitch angle changes, so the lift generated by each blade changes and as a result the helicopter becomes 'unbalanced' and so tips towards whichever side is experiencing the lesser amount of lift.

The illustrations below show the effect of cyclic control on the swash plate and rotor blades. As the swash plate is tilted, the opposing rods move in opposite directions. The position of the rods - and hence the pitch of the individual blades - is different at any given point of rotation, thus generating different amounts of lift around the rotor disc.

To understand cyclic control another way is to picture the rotor disc, which is the imaginary circle above the helicopter created by the spinning blades, and to imagine a plate sat flat on top of the cyclic stick. As the stick is leaned over in any direction, so the angle of the plate changes very slightly. This change of angle corresponds directly to what is happening to the rotor disc at the same time ie the side of the plate that is higher represents the side of the rotor disc generating more lift





Rotational (yaw) control

At the very rear of the helicopter's tail boom is the tail rotor - a vertically mounted blade very similar to a conventional airplane propeller. This tail rotor is used to control the yaw, or rotation, of the helicopter (ie which way the nose is pointing) and to explain this we first need to understand torque.

Torque is a natural force that causes rotational movement, and in a helicopter it is caused by the spinning main rotor blades; when the blades are spinning then the natural reaction to that is for the fuselage of the helicopter to start spinning in the opposite direction to the rotors. If this torque isn't controlled, the helicopter would just spin round hopelessly!
So to beat the reaction of the torque, the tail rotor is used and is connected by rods and gears to the main rotor so that it turns whenever the main rotor is spinning.
As the tail rotor spins it generates thrust in exactly the same way as an airplane propeller does. This sideways thrust prevents the helicopter fuselage from trying to spin against the main rotor, and the pitch angle of the tail rotor blades can be changed by the pilot to control the amount of thrust produced.

Increasing the pitch angle of the tail rotor blades will increase the thrust, which in turn will push the helicopter round in the same direction as the main rotor blades. Decreasing the pitch angle decreases the amount of thrust and so the natural torque takes over, letting the helicopter rotate in the opposite direction to the main rotors.
The pilot controls the pitch angle of the tail rotor blades by two pedals at his feet, in exactly the same way as the rudder movement is controlled in an airplane.
NOTAR is an alternative method of yaw control on some helicopters - instead of a tail rotor to generate thrust, compressed air is blown out of the tail boom through moveable slots. These slots are controlled by the pilot's pedals in the same way as a tail rotor is. To generate more thrust, the slots are opened to let out more air, and vice versa.
NOTAR helicopters respond to yaw control in exactly the same way as tail rotor models and have a big safety advantage - tail rotors can be very hazardous while operating on or close to the ground and in flight a failing tail rotor will almost always result in a crash.

Throttle control

The throttle control is a 'twist-grip' on the end of the collective lever and is linked directly to the movement of the lever so that engine RPM is always correct at any given collective setting. Because the cyclic and collective pitch control determines the movement of the helicopter, the engine RPM does not need to be adjusted like an airplane engine does. So during normal flying, constant engine speed (RPM) is maintained and the pilot only needs to 'fine tune' the throttle settings when necessary.

There is, however, a direct correlation between engine power and yaw control in a helicopter - faster spinning main rotor blades generate more torque, so greater pitch is needed in the tail rotor blades to generate more thrust.

It's worth noting that each separate control of a helicopter is easy to understand and operate; the difficulty comes in using all controls together, where the co-ordination has to be perfect! Moving one control drastically effects the other controls, and so they too have to be moved to compensate. His continuous correction of all controls together is what makes flying a helicopter so intense. Indeed, as a helicopter pilot once said... 
"You don't fly a helicopter, you just stop it from crashing"!

Thursday 29 September 2011

MicroBeast Flybarless Setup





 MICROBEAST has an aluminum composite design casing. Its slight di­men­sions allow it to be installed in practically any model helicopter. MICROBEAST can be installed horizontally as well as vertically.

The sensory system is based on the newest MEMS technology. Software with sophisticated sensor data processing makes installation in electrical & nitro model helicopters possible.


With an optional adapter cable, MICROBEAST can also be utilized solely as a tail gyro. This is recommended especially for whoever is switching from the conventional paddle system and wants to slowly approach the RIGID operation with the 3 axle solution (3G-Gyro Mode).


The well-thought-out and easy setup goes smoothly with no need of an expensive programming box or computer. This makes it easy to still change a number of settings even at the airfield.


Moreover MICROBEAST's integrated swashplate mixer enables the use of simple remote control systems which do not have their own swashplate mixing (NO-MIX).


MICROBEAST is able to process many types of sum signals (PPM / S-BUS / Spektrum). With the optional Spektrum Satellite Adapter, installation in indoor model helicopters is also possible without a great number of wires.


Updates and advanced setup possibilities (Setups) can be done com­fortably with the optional USB interface „USB2SYS“ via the BEASTLINK interface. Software for Windows & Mac can be downloaded free at www.BEASTX.com.


Microbeast V1 setup part 1    

general considerations 

 

Microbeast V1 setup part 2 


Microbeast V1 setup part 3 

 

Microbeast V1 setup part 4



Videos on individual Setup Menu Points:

Setup menu point A: 
Mounting orientation of the MICROBEAST




Setup menu point B: 
Swashplate servo frequency



Setup menu point C: 
Tail servo center position pulse length



Setup menu point D: 

Tail servo frequency





   
Setup menu point E: 
Setting the Tail rotor endpoint



Setup menu point F: 
Setting the Tail sensor direction











Setup menu point G: 

Adjusting the swashplate servo centering







Setup menu point H: 

Swashplate mixer



Setup menu point I: 
Setting the swashplate servo directions



Setup menu point J:  
Teaching the cyclic pitch geometry







Setup menu point K:  

Adjusting the collective pitch range


 
Setup menu point L:  

Adjusting the cyclic swashplate limit






Setup menu point M:  

Setting the swashplate sensor directions



Setup menu point N: 
Setting the pirouette optimization direction (by sutty)









Programming A Helicopter Remote Control

We will try and describe the most common functions on a computer radio in helicopter mode. Note that the syntax may be different on different models and makes, but odds are it's there. I own futaba radios, so my terms will coenside with theirs. Some of these terms may be in the glossary as well.
You might also be interested in our article about Controlling RC Helicopters.
If you want you can skip to the Typical Beginner Setup, or the Typical Intermediate Setup, or the Typical Aerobatic / 3D Setup. Click here to Add Your Remote Control Programming Tips and read what other pilots have said on the matter.


The Switches

 

Idle Up 0,1, 2 (switch)

Idle Up 0, or Normal Mode as it's called, is for take-off and forward flight. Typically, this has the lowest RPM of the three idle-up settings which makes the controls less sensitive making it easier to hover with accuracy.

Idle Up 1 is your "sport" mode. It is for Fast forward flight, high speed turns with sharp cornering as well as loops and rolls. This has a slightly higher RPM, somewhere around 1600. Also, the bottom of the collective in this mode probaly won't be set for idle on the throttle.

Idle Up 2 is your aerobatic or 3d mode. Usually, this is a symetric throttle curve, meaning at full down on the collective, you're at full throttle so you can climb inverted. Then, in the mid stick, which would be 0 degrees of collective, you've still got plenty of power for doing tumbles.


Throttle Hold (switch)

This switch is used to disconnect the mixing of the collective with the throttle. By flipping this switch you can apply full collective pitch while having the engine stay at idle. You use this switch to practice autorotations and in the event of a tail failure. By cutting power to idle, the helicopter will stop spinning if the tail fails and give you a chance to autorotate to the ground. This mode usually has it's own pitch and throttle curve.

 

Throttle Cut (switch)

This switch is used to turn off your motor. Usually this switch only works if your throttle is at idle, or a very low position so that accidentily hitting it while you're flying won't force you to autorotate.

 

Trainer (switch)

This switch will let a second remote (plugged into your remote) take control of your aircraft so long as it's held. The moment you let go of the switch your remote is back in control. Usually, the instructor holds the remote that belongs to the flying aircraft and the student holds the extra remote.

 

Hover Pitch (knob)

This knob will let you adjust the pitch near the middle of the collective so that you can increase or decrease it. Ideally, you should be hovering around 6 degrees in Normal mode.

 

Hover Throttle (knob)

This knob will let you adjust the throttle near the middle of the collective so that you can fine tune your RPMs in a hover. Your target is 1550 RPM in a hover while in Normal flight mode.

 

Revolution Mixing

This mixes tail rotor with throttle. (which is mixed with collective) As you add collective you need more power to maintain your head speed, but once power is increased so is the torque which means you need to add rudder. This mix lets you program in some percentages so that the remote does most of the work for you.

To set this value you want to hover your helicopter and use your trims so that it does not spin in a hover. Then, after you land you want to program in or tweak your revolution mixing so that as you add or remove power while hovering the tail stays still. Which way you adjust it depends on which direction your rotor blades spin. In the U.S. they spin clockwise, so if you add power and the helicopter turns to it's right you have too much and need less mixing. These values require a lot of trial and error. If you have a heading hold gyro you must inhibit this function because the gyro will automatically compensate for anything including torque from the motor.

In 3D mode, your revo mixing should be a v-curve similar to your throttle curve so that as you add power for inverted hovering, you're also adding revo mix.

 

Throttle -> Needle Mixing

This will let you program in adjustments to the high speed needle valve at various amounts of throttle. Most people don't use this feature as it requires an extra servo.

 

Rudder Offset

This lets you set a different trim position for higher rpm modes, like idle-up 1. Since there is a higher rpm, there is more torque and thus will require a different trim setting to hold a steady hover. This is another trial and error function where you must land and tweak the settings. This function is also inhibited if you have a heading hold gyro.

 

Invert Mode

Not really used any more, this mode (when activated by a switch) would reverse the elevator and rudder controls so the helicopter would respond as if it were right-side up. You have to switch it back and forth as you go from right-side up to upside down. Don't use this!

 

Throttle Curves

Throttle curves tell the helicopter how much throttle to use at which collective setting. All radios come with a linear curve, so 0 throttle coorisponds to 0 collective, and 25% with 25%, 50% with 50%, 75% with 75% and full collective with full throttle. This linear "curve" rarely will maintain a constant RPM, which is your goal. You can fine tune your throttle so power is applied when needed to maintain a constant rotor speed.

There are many throttle curves, one for each idle up so that you can change how much power is applied with collective.

 

Pitch Curves

Pitch curves alow you to adjust the way the collective responds to the collective control. Most people leave it linear (0/25/50/75/100) but some people like to make the middle of the stick less sensitive (similar to exponential) for example 0/35/50/65/100. This way, the middle of the collective will be much less sensitive allowing you to hover more gracefully. It's up to you if you adjust these values, but bare in mind that you'll need to tweak your throttle curves in a similar way to maintain constant RPM. Pitch curves also have their own settings for each flight mode (idle up) as well as throttle hold. Some people have extra pitch (too much pitch for flying around) in throttle hold for that last bit of umph when landing with no power.

 

Programable Mixing

This will let you set up custom mixes from either switches or controls. You can for example mix power with cyclic, since every control movement takes power which will lower the RPM.

 

ATV

Adjustable Travel Volume lets you set the limitations on servo travel so that you don't "bind up" any controls. Thats what happens if your control arm can only turn so far, but your servo wants to keep going. This is hard on the servo and can break it, so you want to set the end-points to prevent it from happening. This is usually the first thing you set because it's the highest up on the priority for the servo movements. When the atv reaches it's limit there is no other function that can over power it to make the servo move more.

 

Sub-trim

You can use these to fine-tune the trim of your aircraft, or use them completely so that you can leave your trim settings centered. The reason you would want to do this is so you have full trim control at your finger tips if you need it, otherwise you might have to have your trim all the way left, and your flying along and something happens and you need more left you wont have any room on the trim lever. The sub trims let you always have room to trim it out in flight. It's best though to get the links physically set to as close as possible so you don't need to use sub-trims.

 

Reversing

This lets you reverse the responce the servo's move to the sticks. You would use this if right goes left or up goes down, etc...

 

Gyro Gain

This lets you set how sensitive you gyro is. If the gyro is set too high, the tail will wag like a dog's tail. If it is set too low it may be hard to control and wander all over. You want to set it as high as possible, but without getting it to wag. Remember that in forward flight the blades are more effective so it may still wag when moving even if it does in a hover. I usually use 5% less sensitivity that the best I can do in a hover because of this.

 

Exponential

This will make the center of the sticks less sensitive and the extreems of the sticks more sensitive, alowing gracefull hovering and snappy rolls. Most people use 15% to 25% expo, but it's only a preference.

 

Typical Beginner Setup

 

Normal Mode

Pitch Curve: 0 degrees / 6 degrees / 10 degrees
Throttle Curve: What ever it takes to maintain a constant 1550 RPM while in flight (including decents) 
Idle up 1
Inhibited (Disabled) 
Idle up 2
Inhibited (Disabled)

 

Throttle Hold (For emergency autorotations)

Pitch Range: -4 degrees / 6 degrees / 12 degrees

 

Typical Intermediate Setup

 

Normal Mode

Pitch Curve: 0 degrees / 6 degrees / 10 degrees (1550 RPM) 
Idle up 1
Pitch Curve: -4 degrees / 5 degrees / 10 degrees (1650 RPM) 
Idle up 2
Inhibited (Disabled)

 

Throttle Hold (For emergency autorotations)

Pitch Range: -4 degrees / 6 degrees / 12 degrees

 

Typical Aerobatic / 3D Setup

  

Normal Mode

Pitch Curve: 0 degrees / 6 degrees / 10 degrees (1550 RPM)  
Idle up 1
Pitch Curve: -4 degrees / 5 degrees / 10 degrees (1650 RPM) 
Idle up 2
Pitch Curve: -10 degrees / 0 degrees / 10 degrees (1750 RPM)

 

Throttle Hold (For emergency autorotations)

Pitch Range: -4 degrees / 6 degrees / 12 degrees
Pitch and throttle curves are totally personal preference though. These are only possibilites. I myself fly all modes with the same pitch range (-10 degrees / 0 degrees / +11 degrees) This way I'm totally used to how the collective responds through all flight modes and it never changes. Many people actually prefer it this way, although it's the most sensitive on the collective. It requires very subtle movements to climb or decend in a hover rapidly.


Setting Up the Helicopter

First, you make the mechanical connections. You want to set up your links so they use as much physical movement on the servo and are close to centered as possible, then you use your radio to fine tune it.
The reason you do this is to get the most "resolution" out of your servos. They only have so much accuracy, and the more travel you can use physcally, the more accurate your controls will be.
As an extreme example, say you have your servo geared so that only 1 degree of motion would move the rudder full deflection. Then the servo must be very accurate to smoothly transition from one side to the other. This isn't the case, there are only a finite number of steps the servo can move, and the more you use, the smoother control you will have.
Also, the more throw you can use, the more leverage and thus power your servo will have.
Second, tweak the connections so that mechanically they conform to the list of pitch ranges above; if you're a beginner, use the beginner pitch ranges etc... Ok, now say you get your pitch range to be -1 / 8.5 / 12. I would slide your mechanical adjustments a bit (by adjusting the links) to be more focused around 6 degrees in the middle. 6 degrees is the optimal hover pitch, because if you're hovering and your blade pitch is 6 degrees, you must be using a good rpm from 1500 to 1600 which is what you want and when you're a beginner, you want to hover at the middle of the stick. If you're at -1 / 8.5 / 12, change the links 2 degrees until you get to -3 / 6.5 / 10. These are more pratical values, closer to what you want went learning.
Thrid, use the atv settings so that you can use as much as the servos as possible, but below the point at which they bind. (Binding is when the link goes as far as it can mechanically go, but the servo tries to move it further)
Before you start actually flying, you should set up your throttle hold and kill switch if you have them. These are saftey features and might save your helicopter or the skin on your back. Set your throttle hold so it has just enough throttle to idle smoothly. You can use this (or kill) if you know you're going to crash or while you cary your helicopter out to the landing pad.
Fourth, set up the pitch curve settings on the radio to make your helicopter accurately conform to the pitch range that suits your skill level. The only reason you want -1 insted of -3 or -6 on the bottom is because no newbie is used to how sensitive the collective is and so is destined to slam it into the ground when they panic and move the left stick down more than they should. By setting this value to a high number (high as in 0, or -1 degrees compared to -4 or -10 like I use) you minimize the damage you'll do when you first panic.
Once your pitch range is set up and accurate, you only adjust the throttle curves from then on. You do not adjust them both here and there then and again. This makes it confusing and impossible to "home in" on a good setting. One problem at a time, so start with pitch, get that set, then work your throttle curves until you get a constant rotor rpm.
Fith, If you have a gyro that is NOT heading lock, you'll need to adjust the revolution mixing (revo mix) function on your radio. This is a two step process; first you must set the 0-degree mid point as a starting refrence. Once your helicopter is set up not to yaw at 0 degrees, you configure the ratio of power to rudder mixing you need when you add or take away throttle. Your helicopter manual should tell you what aproxomate settings to start with. It's difficult for a newbie to set this portion of their radio up, because the best way to do it is to fly up and drop the collective to 0 degrees. The helicopter will drop very fast, but by watching which way the helicopter turns on it's way down you will find out if you need to add more mixing or less mixing. This 0 degree fall is used to set your anti-torque at the lowest point of torque. After that, you set the mixing percentage of throttle to rudder; that is, the more power the more you need the radio to correct for the torque by adding rudder automatically. Same for decending, when you need to take rudder away while there is less or no torque.
After that, you can set expo if you like. This will help soften the center of the sticks so you don't over react, but leave room for the hard yank and bank you may need in an emergency.
After you get used to the sensitivity and don't over-react, you'll want at least -4 degrees on the low end so you can do an autorotation if you have to.
Eventually, you'll want all the range you can get, symetric if possible. I fly -11 / 0 / 11 on my raptor. On the nexus, I could only get -6.5 / 2 / 8.5 because of the mechanical design limitations. This is barely enough for inverted hover and minimum positive pitch for autorotations.

Friday 23 September 2011

RC Heli Flight School

What is 3D....
3D is a style of helicopter flight which makes the helicopter appear to defy gravity by flipping , rolling and moving  in “3 dimensional space” sometimes on the spot, which would not otherwise be possible in full size helicopters. There is not really a clean explanation of what 3D is …often a video helps.

Auto – Pushover


Start out in an inverted auto and then pushover to a tail first landing. The key to this trick is getting the right amount of forward speed while inverted. Start out high to get the Fwd speed and timing correct.

Auto – Tumbling S




Another trick to be performed while autoing

Sustained Pirouette Flips

Pirouette while flipping which is essentially keeping the cyclic in phase with the yaw of the helicopter in order to maintain the flip. Repeat the maneuver over and over and you have your: “Sustained Pirouette Flip”



Chaos Again this involves Piro-Flips however this time between each individual Piro-Flip, the axis of the flip is rotated. You follow the same principle that is being applied in the Piro-Globe.

Death Spiral


As the name suggests this can be a quite dramatic maneuver when performed to the limits.

Start with plenty of height in a stationary hover then 1/4 roll the model to knife-edge then Set collective to 0 deg. As the model falls apply fwd or bwd cyclic. The model will be rotating about the axis which it is falling. To exit, stop the application of fwd/bwd cyclic and 1/4 roll again. Depending on the direction you roll out, will lead to a normal or inverted pullout.

The rate of descent can be slowed by applying the Stationary Death Spiral philosophy.

Death Spiral – Stationary

The stationary death spiral is a development of a Fwd inverted circuit. By decreasing the diameter of the circuit until the model is effectively turning on the spot. To sustain height the model obviously isn’t knife-edge, as with the death spiral. However the model is at a very steep angle.

Once the stationary death spiral has been mastered the heli can be sent round circuits and climb in this manner, with the use of collective.



Detonator


One of the 3D Masters set maneuvers. See pic. Basically a climbing then falling funnel. But, for this manoeuvre a skids in and out funnel are required.

Start in a Funnel, skids IN, and low (tail down for this example). Then power up vertical, maintaining the funnel. At no point should the diameter of the funnel increase/decrease.

At the top put the model Knife-edge tail down, but keep rolling the heli. Then transition to a funnel but this time skids OUT. Now bring the heli back down to the starting point, in the funnel.

For clarity the upwards and downwards section are shown side-by-side in the picture. But, the idea is to go straight up, then straight down. Like the Plunger on a ‘Detonator’.

Funnel




See Pic. The example shown is tail-down inverted. This seems to be the most popular variant. But there are of course many different variants.

The funnel is a development of sideways circuit flying. By reducing the size of the circuit until the tail (in this example) is turning almost on the spot. Increasing the collective pitch while still maintaining height will force you to increase the angle of the model, and vice-versa.

The transitioning between the different variants of a funnel, is known as morphing funnels.

Hurricane




The ‘Hurricane’ is a high speed knife-edge circuit (Basically the same as a Wall of Death).

By using high collective values the angle of the model can be made to appear on the knife-edge.

TIP: By flattening out the circuit @ positions B/D allows more lift to be created, so that @ positions A/C the model can actually be put on the knife-edge. As A/B are the positions at which the spectators view the model on the knife-edge, it increases the illusion that the model is knife-edge all the way round.

Hurricane – Flipping


Move is seen in the picture from birds eye view

Tic Toc


A metronome is a way of achieving ‘knife-edge’ flight with a helicopter. See Pic. When viewed on (A) it appears that the heli is holding a knife-edge attitude. Also known as a Tic-Toc. Using the metronome as a flight mode, it is then possible to perform, metronomic circuits, Figure 8s, Loops and the Big Ben Clockface.

Pie Dish


Similar to a funnel but the size of the circuits is much bigger and the angle of the heli is lower, giving the ‘pie dish’ shape to the man’vre.



Pirouetting Globe (picture from birds eye view)




  1. Enter maneuver pirouetting traveling E to W.
  2. When central (C) to pilot/judges start Piro-Loop (PL1) travelling E to W.
  3. Complete PL1.
  4. When back at the center (C) rotate direction of travel by 45°.
  5. Perform PL2, starting loop traveling NE to SW.
  6. When back at the center (C) rotate direction of travel by 45°
  7. Perform PL3, starting loop traveling N to S. (i.e., looping into yourself to start).
  8. When back at the center (C) rotate direction of travel by 45°.
  9. Perform PL4, starting loop traveling NW to SE.
  10. When back at the center (C) rotate direction of travel by 45°.
  11. Perform PL5, starting loop traveling W to E (Parallel to flight line).
  12. Once PL5 is complete exit maneuver traveling W to E pirouetting.

So you enter and exit the maneuver at the same point (C), but exit traveling in the opposite direction.

Now you could decrease the angle of rotation change to say 30°, 15°, 10°………etc. Therefore increasing the number of piro-loops to the globe. To make it look good, I think a 45° change is the minimum requirement.

The other variation is to continue rotating by another 45° after PL5 and continue round. This would give 9 piro-loops and exit traveling E to W. This is gonna be hard, because you now have to be able to piro-loop away from yourself.

Pirouetting Loop


The example shows 2 complete pirouettes per loop, you can of course do as many piro’ you like per loop. The pic shows a piro-loop, using right tail rotor input.

Pirouetting Outside Loop


The outside version of the pirouetting loop.

Pirouetting Vertical 8


One of the 3D Masters set maneuver.

Pitch Pumping

Not really a man’vre in itself I believe. Pitch pumping has arrived with the advent of big block powered machines, were pitch can now be used to add a dramatic visual effect to a more ‘traditional’ maneuver. As it sounds, pitch pumping is basically moving the collective from say -5deg to + 5deg in rapid succession.



Rainbow


A rainbow is basically a large 1/2 flip but holding the collective until the end of the flip. By varying the amount of cyclic and collective determines the size of the rainbow. The rainbow can be carried out Fwd/Bwds, Sideways and Piro’ing.

Ripper

Basically a Pirouetting Tail Slide. As the falling speed increases, the demands on the tail system become VERY HIGH. Only attempt this maneuver if you are 100% confident in your model.



Slapper


3D Masters Move – This maneuver consists of a series of tailboom-vertical metronomes with a half aileron roll between the metronome stop points. 6 pitch reversals are required, and the model will retain constant tailboom orientation. The roll will be centered at the mid-point of the arc.

Snake


The snake is performed on the ‘knife-edge’. Pic shows a birds eye view.

To perform the example shown, you need to be able to perform (1) A tail-first inverted clockwise knife-edge circuit and (2) A tail-first normal anti-clockwise circuit. Then bring the 2 together and perform 1/2 circuit (1) then transition to the other (2), and so on down the flight-line.

Like most tricks there are multiple variants to practice and master. (NOTE: Pic shows the heli completely knife-edge, this obviously is not possible, but it was much easier to create the pic that way)

Sudden Stop

One of Jason Krause’ signature moves. First get the heli traveling at great speed Fwd Normal Flight. Then pull back elevator quickly and do a 1/4 back flip to vertical, then punch more positive collective. The heli will suddenly stop its Fwd motion. The key to getting a dramatic sudden stop is the cyclic to collective timing.



Tail Slide

Take the model up high and then point the tail at the ground. The model will accelerate and end up falling tail first very fast !!!



Tornado


The Tornado is a combination of a pie dish up-high morphing into a funnel down- low.

Wall of Death

The Wall of Death is basically the same as a Pie Dish, but with the heli at a near vertical attitude.



Waltzer


Another one of the new 3D Masters Set Maneuvers
The maneuver involves performing multiple funnels while sending the heli around a circuit.

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Heli Flight school

Below you will find links to videos that will guide you through learning how to fly an RC Helicopter.  These short heli training videos are geared towards getting your RC helicopter up in the air fast by showing you what to practice.   Following these steps and practicing each level will build muscle memory, orientation, sport flying, 3D skills and give you the confidence you need to improve your rc heli flying at the field.   The intended audience is sport to intermediate 3d pilots.   Even if you are doing 3d moves test yourself and see if you have any weaknesses in these levels.  Make sure you practice and master each level before you move up.   In just 30 minutes a night or less you can learn to fly an RC helicopter and become a master 3d heli pilot.

Practice 30 minutes a day and try to master every move before moving up a level.  It may take weeks to master a level and you will crash a million times before some of these moves click.  Keep trying  every night!
  
Level 1 – Hovering upright

 

This video describes some of the first steps to learning radio controlled 3D flight. It is important that you have a solid foundation of skills in order to advance to the next level of flying. When I first started I searched high and low for information on how to learn to fly 3D. What I found was a lot of outdated information from an era before simulators. Hopefully this video series will help guide people on how to advance quickly with a simulator.
Remember to slowly transition what you learn in the sim to the field. Things don’t always go as well in real life. But learning tail-in, side-in and nose-in hovering will really boost your confidence and get you started.

Learn upright hovering, rudder control and orientation.  Hovering side on, tail in and nose in be difficult.  This video shows you in a few minutes what to practice to hover an RC helicopter upright.  Practice:
  • Tail at 45 degrees offset
  • Side in viewing the helicopters left and right side
  • Nose in with the tail directly away and offset
  • Stretch: Pirouette back to tail in. Backward flips
  • Bonus:  Forward flight circle
Level 2 – Hovering inverted


Learning to hover inverted can be challenging and frustrating.  But in the last few years simulators and computers have really advanced.  So learning to fly upside down can be as easy as upright.  If you want to learn to fly 3D and are just getting started make sure you start on this step within the first couple of months.  Once your brain realizes that RC helicopters can hover upside down as easily as upright you will be well on your way.  Make sure you practice Nose in, side in and tail in inverted hovering.
It will take some time for this to sink in completely.   Just keep practicing 30 minutes a night and it will come to you.  When you first try this at the field make sure you have a lot of altitude and know which way you want to bail out.

Inverted hovering is difficult because our brains don’t want to believe a heli can fly upside down.  Follow along on this video and master rudder control and the soft feel you need to hover an RC helicopter while inverted.  Practice:
  • Tail offset 45 degrees on each side
  • Side in looking at the heli on the left and right
  • Nose in inverted
  • Stretch: Forward flips, Rolls, Inverted piro to tail nose in.
  • Bonus: Inverted forward circle
Level 3 – Flying in circles


Finally the start of some real flying.  In this step you will learn to fly in circles.  It is really important that before you move into this level that you have a really good grasp on upright and inverted hovering.  If you can’t hover in an orientation you can’t fly in it.  A lot of people get started learning figure 8’s first but I like to focus on circles first.  The reason is without good practice in grooving a circles you end up doing lazy figure 8’s.  In lazy 8’s the circles are elongated and cross like an x in the middle.  If you learn circles first you will be able to focus on the transition in a figure 8 and not so much how to maintain flight.    I’ll leave it for a later lesson but the transition in a figure 8 is the key to a lot of 3D flight maneuvers.

Keep up your hard work on this lesson.  You will likely crash every time but just keep trying the flight directions equally.  It will pay off in the end and you will eventually get it!

Learn to fly an RC helicopter in circles and keep it on a constant heading without increasing to decreasing in speed.  Controlling the cyclic and elevator movements you will learn to groove the heli into a circle and keep it there.  Practice:
  • 5 forward circles left and right
  • 5 backward circles left and right
  • 5 inverted forward circles left and right
  • 5 inverted backwards circles left and right
  • Stretch: Forward loops, Backward loops,Tail down tic tocs
  • Bonus:  tail down rainbows, stationary piros
Level 4  –  Flying in Figure 8’s 


In this video lesson you will go through how to learn to fly figure 8’s.  This is the next step beyond learning to fly in circles and will help you groove in your circles even better.  Figure 8’s are great to practice to improve your orientation and advance your 3d flight.  In the bonus section you will see morphing figure 8’s, stall turns with changing orientation and side on tic-tocs.  Make sure you practice this every night and keep trying until you can complete 5 figure 8’s in a row without crashing in each orientation.

Once you complete circles the next step is to learn to fly an RC helicopter in figure 8’s.   The main thing you are learning is the transition between one circle to the other.  Don’t cheat and do lazy 8’s make sure you come around in as perfect a figure 8 as possible.  Practice:
  • Switch this move so the figure 8 crosses towards you and away from you.
  • Forward
  • Backwards
  • Inverted
  • Inverted backwards
  • Stretch:  Snake transition in figure 8 with 30% bank angle, Side on Tic-Tocs
  • Bonus:  Stall turns changing orientations at the top of the turn
Level 5  –  Learning funnels


Learning funnels can be challenging work.  Once your have a solid foundation in circles and figure 8’s a natural place to go is funnels.  But most people get discouraged by how unnatural this flight direction can be.  This video will walk you through how to get started learning funnels.   The video also emphasizes a training plan that has you perform 5 funnels in a row in each flight orientation until you have mastered the skill.   Learning to fly funnels can be a lot of fun and trust me your brain will give up eventually and agree that sideways flight is possible.

Something about remote control helicopters in sideways flight looks cool and seems so wrong to our brains.   Think about doing circles and focus on grooving in your funnels.  The key is to reverse your aileron and elevator cyclic movements  from a circle and let them go.   Practice:
  • 5 upright tail down, left and right
  • 5 upright tail up left, and right
  • 5 inverted tail down, left and right
  • 5 Inverted tail up, left and right
  • Stretch: Funnel figure 8’s
  • Bonus:  slowing down funnels and changing the speed
Level 6  –  Learning loops


Learning how to fly loops in every orientation is essential for the developing 3D pilot. In this video you will learn how to fly loops in every direction and get key insight on how to perform the loops. Make sure that you keep the loops parallel to yourself and the flight line. This will be key later in your flying when you start to mix loops into your routine. Also, it looks much more impressive when you have the loop centered in front of yourself and the heli is side on the entire move.
Make sure you practice this for 30 minutes a night until you can perform at least 5 loops in each flight direction without crashing. And when you get to the field start off by trying these loops high enough that you can recover if you make a mistake or get disoriented. As with the previous videos in the Flight school training guide this is a fly along video. Basically you want to practice exactly what I am doing in the video.
Enjoy and good luck

Performing large loops with an RC heli can really be fun.  Work on these and controlling your inputs on the simulator before you go the field.  Also remember with a flybared helicopter that you will need to give constant cyclic inputs during a loop to keep everything in sync.  Practice:
  • 5 inside forward, left and right
  • 5 inside backward left, and right
  • 5 outside forward, left and right
  • 5 outside backward, left and right
  • Stretch: Vertical loop figure 8
  • Bonus:  Sideways loops
Level 7  –  Morphing or Transitions 


At this stage you have developed a good base level of skill in hovering, circles, figure 8’s, loops, rolls and flips.  The next step is to work these moves into your 3D heli routine by morphing from one flight orientation to another.  In the old days it was difficult to practice this.  But with the use of a simulator and regular practice you will be switching orientation right in the middle of a figure 8 or hurricane.   Doing transitions and morphing between orientations really adds an interesting piece to your flight plan.   Start by practicing half flips and rolls until you are comfortable.  then add rudder until you can perform a roll and go from tail in upright to tail in inverted.  If you have trouble stabilizing the heli after this maneuver then you should go back and practice hovering.


Learn to fly figure 8’s, hurricanes and the mobius with your RC helicopter.   The video lesson will show you how to practice morphing from one orientation to another in flight.    Follow the video and steps below and practice:
  • 5 of each figure 8 morphing orientations
  • Forward upright to inverted going left and right
  • Backwards upright to inverted going left and right
  • Upright funnel to inverted left and right
  • Verticle loop figure 8’s left and right
  • Horizontal loop figure 8’s going left and right
Level 8  –  Rolling travel

 
  • Rolling in a straight line forwards and backwards
  • Rolling circle forward left and right
  • Rolling circle backwards left and right
  • Rolling figure 8’s
Level 9  –  Pirouetting travel


                                           


In this video lesson you will learn how to break down and practice pirouetting moves with an RC Helicopter. First you will work on hovering while pirouetting and move into piro travel in a straight line and eventually piro circles. Following piro circles you will start to work on the move everyone wants to do at the field the famous piro flip. Once you have a good grasp of the piro flip you will work on morphing piro flips and piro snakes.. anything is possible.
Remember nothing is as hard as you think. It might take you a very long time to get this down possibly even months just to piro hover. Stick with the training because one day your brain will get the movements and it will become automatic. I have been working on this move for 18 months now and as you can see I still have flaws in my skills.
Enjoy and good luck.


Flying an RC helicopter while is is pirouetting can be challenging.  This video will walk you through how to learn to fly your RC helicopter while it is doing a piro.  Or as most people describe it this the video with show you how to fly piro moves with an RC helicopter.
  • Pirouetting in a straight line left right, inverted
  • Piro circle upright
  • Piro circle  inverted
  • Piro flips
  • Piro Figure 8 Upright
  • Piro Figure 8 Inverted
Level 10 Direction
 
Go back and practice all above in the direction you were most uncomfortable.

Level 11  –  3D Genius – Mastery
  • 4 point tic-tocs and traveling tic-tocs
  • Death spiral and low tail slides
  • Flappers
  • Piro Rainbow
  • Piro Snake
  • Piro Loop
  • Piro Tic-Tocs
  • Big Ben
  • Piro flip Reversal
  • Pitch Pumping
  • Flipping Hurricains (circles)
  • Slinky (circle, 45deg circle, edge loop (viewed as loop from side), 135deg circle, circle)
  • Smackdown Flying
  • Smooth transitions between moves
 Level 12 –  Unbelievable stuff
  • Chaos (piro flip with rotating axis)
  • Piro Snake Figure 8
  • Piro Globe
  • Fliping Funnel 8
  • Reversing Piro Tic-Tocs
  • Reversing Piro Rainbow
  • Reversing Piro Snake
  • Kruezenburger
  • Reversing Piro Funnel
    Wheel of Fortune
  • London Eye(piro tic-toc loop)
  • Piro Vertical Figure 8
    Piro Slinky (variation of globe where you start with piro circle (start at left or right side of pilot), piro 45deg tilted circle, piro loop, piro 135deg tilted circle, piro circle (opposite side of pilot from the first circle)

Autorotation


                                            
  


An autorotation is a procedure where a helicopter can make a controlled approach and landing after motor failure, or deliberately cutting the power mid-air with the throttle hold switch on the transmitter.

An autorotation consists of two phases. Immediately power is lost, the collective is lowered and the pilot establishes an autorotative glide, where air flowing through the main rotor from bottom to top causes the rotor to maintain RPM (much like a windmill) and generate sufficient lift to make a controlled descent. As the helicopter approaches the ground, the pilot executes a flare, converting the helicopter's forward speed into additional rotor velocity and lift, and allowing the helicopter to establish a brief hover before landing, or perform a gentle running landing.

The main rotor is able to freewheel during autorotation due to a one-way bearing in the transmission. Depending on the location of the one-way bearing in the transmission, the tail rotor may (or may not) be driven from the energy gained by the main rotor, making it easier to maintain or change the helicopter's heading throughout the autorotation.
Autorotation performance is greatly affected by the size of the helicopter. 450-size helicopters can be autorotated but there is very litte spare energy at the end of the approach. Larger helicopters, such as 600 size machines, are much easier to autorotate and have much more hang time---the amount of time the helicopter can hover before the main rotor loses useful lift---making the procedure much more tolerant of error.

Autorotations can also be performed inverted (with positive collective pitch added): often the inverted section will be flown backwards, to enable the flip to upright to be made a part of the flare while minimizing the risk of hitting the tail on the ground. Another variation are blade stop autos, where the pilot deliberately adds positive pitch to slow the main rotor almost to a stop, then gives negative pitch to spin the rotor again---hopefully giving enough energy to complete the autorotation with the helicopter in on piece.

Autorotation practice is typically started by performing hovering autorotations from no more than 1 meter above the ground so the pilot can learn how much energy is stored in the main rotor. As the pilot becomes more confident, short practice autos can be performed from 1-3 meters in slow forward flight in approach for landing. Ideally, autorotations are performed into the wind, as the increased airspeed will give the helicopter increased translational lift. In practice, the engine may fail at inopportune times!

An autogyro is an aircraft that generates all its lift by a constantly autorotating main rotor, with forward power provided by a pusher prop.












Pilot : Zahidin Mohd Zahid
http://www.facebook.com/zahidin.zahid