Introduction to Aerobatics

Once you have passed your bronze wings (and in a lot of cases before) the first thing you want to do is start throwing your model around the sky like a lunatic so that everyone will be impressed by your incredible skills on the sticks.

However, there is a safe way to go about it and a not so safe way – so I thought I should start writing a series of posts on how to improve your aerobatic skills…

Finding a suitable model

Not all models are aerobatic although most can be made to do some manoeuvres, and before you start mentioning Bill Hempel flying 3D freestyle with a 50% Cub on YouTube don’t get your hopes up – but it does prove that anything is aerobatic if you modify it enough.

We can show you ways to improve the performance of your trainer by increasing the throws on your control surfaces and changing the incidence on your wings.  This is probably the safest way to go as your trainer will still have some inherent stability that could save some expensive accidents.  Once you get more confident you can move on to a more advanced model.  I would recommend starting with an advanced low-wing trainer before you refinance the house and get that 2 meter 50cc TOC Extra 260!  Things to look for in an advanced trainer include…

  • Low or mid-mounted wings
  • Semi-symetrical or symetrical wing section
  • Larger control surfaces, possibly with a servo on each aileron
  • Rudder, elevator, aileron, and throttle control

Stick with something that still has a trainer type construction – box type fuselage, built up wings and solid tail feathers – this will make it easier to repair when you have those almost certain mishaps.

Moving onwards and upwards

Once you have the basics of aerobatics mastered and want to move onto something more advanced you need to decide where you want to focus your attention.  There are three main types of aerobatics (as defined by competition):

  1. Precision – Popular in Europe, this is highly specialised models flying extremely precise aerobatic figures to a predetermined schedule.  Precision aerobatics is not for the faint hearted and takes a lot of practice (and a lot of money) to master.
  2. 3D/Freestyle – All the rage at the moment, these are the models that hang around in the air for ever and perform manoeuvres with names like ‘Blender’, ‘Waterfall’, ‘Wall’ and ‘Harrier’.  Freestyle rounds in competition are often flown to music.
  3. IMAC – The International Miniature Aerobatics Club is the small version of the IAC.  Competition models must be scale in appearance and fly scale type aerobatic manoeuvres.  Planes are often large petrol engine powered models.

At the moment the most popular models are those that are either total 3D/Freestyle models or IMAC style scale models.  If I was to recommend a model type then it would be a scale IMAC model such as the Extra 260, Yak54, SU26, Extra 330 or Edge 540 as these models are light and strong and can be flown with precision on low rates or 3D with high rates.

A note about size…

There are lots of good models out there and sometimes it can be hard to choose what you want to fly.  A lot of people are doing very well flying small foam models such as ‘Shockflyer’ style models or the Multiplex Acromaster.  These are fine electric models with good performance in light winds which help build confidence without putting a huge dent in your wallet.

Larger models around the .46 to .60 size are the most popular.  They will return a good performance for a pretty good price, and will still fit in the car easily.

More and more people now are turning to larger models with petrol engines.  1/4 scale models with 25cc engines are the smallest seen in competition these days with 50 – 100cc being popular with the experts.  The truth of the matter is that – when it comes to advanced aerobatics – bigger models fly better and are easier to lock into the hover.  They do however cost a lot of money and you have to ask yourself how confident you would be practicing rolling harriers 6 inches off the deck with the kids college money?!?!

Well that’s it for this post.  Next time we’ll start looking at some aerobatic theory so we can begin to practice safely…

Flying lessons are now online!

I have now put all of my flying lessons for Bronze Wings students onto the site.

These lessons should form a good basis for any model pilot wanting to learn the skills required to be able to pass the bronze wings test.  I should be noted however that these lessons are intended as a framework for learning to fly and DO NOT replace the instruction given by one of the clubs qualified instructors.

I have left the comments sections open on the lessons so that anybody who wants to add tips or tricks they have learnt along the way can add them to the bottom.

Lesson Nine – Bronze Wings Rehersal

Learning Objectives

  • To be confident in taking and passing the Bronze Wings Test

BronzeWings

 

Bronze Wings Rehearsal

In this lesson your instructor will take you through the full Bronze Wings test to prepare you for the real thing!
The following is reproduced from the test schedule issued by the Model Aeronautical Association of Australia:

1. DEXTERITY
Pilot must be able to locate all the transmitter controls quickly without fumbling.

2. THEORY
Pilot must be able to name all major components of the aircraft and define functions including effect of controls and have a thorough knowledge of safety rules and regulations.

3. AIRFRAME & PRE-FLIGHT CHECK
Check engine mounting, plumbing, centre of gravity location, throttle setting, under-carriage secure, and signs of structural or covering problems that could affect flight e.g. Controls neutral and control throws correct, presence of warps which could affect trim, state of battery and range check.

4. TAKE OFF
Use gradual application of power while keeping the aircraft straight, and using a little elevator to lift off, then making a gentle climb out with wings level until safe altitude is reached.

5. TRIMMING
Pilot to show ability to trim aircraft in flight. Displacement and re-trimming both the primary roll control and elevator should be demonstrated.

6. PROCEDURE TURNS – One in each direction.
The pilot’s ability to perform the following steps in the procedure turn will be monitored.
a. Level flight segments should be straight and level.
b. Aircraft should pass directly over the landing area.
c. Turns should be at a constant altitude.
d. Turns should be completed in order that upwind and downwind tracks are superimposed.

7. LANDING CIRCUITS
In both directions, as shown in the diagram in the M.A.A.A. Pilot Log Book, with all turns of 90 degrees. With high performance aircraft the power needs to be reduced much sooner than at the turn onto base leg. The upwind and downwind legs are parallel to the landing strip. The first three legs are maintained at a constant height and a gradual approach angle is started at the beginning of the base leg.

8. APPROACH & LANDING
With engine assisted landings (approximately 1/4 power or suitable power setting depending on the model set-up allowing the model to descend under power) control nose attitude and therefore airspeed with elevators and use the throttle to place the aircraft where you want it to be. The aircraft should be flown over the threshold at an altitude of about 1.5 metres, the throttle closed, and as the aircraft settles towards the ground the round-out or flare is initiated. The “hold-off” period is then commenced where the aircraft is gradually allowed to sink and settle on the ground in a slightly nose high attitude.

9. SIMULATED DEAD STICK LANDING
At a safe and high position the student will reduce the throttle to idle and perform a descending circuit to show his/her ability to safely glide the model without engine power to a position where a landing approach can be executed.

Your instructor will give you tips on how to approach each of these tasks and the best way to fly the manoeuvres to impress your examiner.

And that is it! You should now be ready to take your Bronze Wings and enjoy the freedom of flying your model whenever you like without having to ask an instructor to accompany you!

After you pass

Do not throw that trainer away too quickly. A trainer aircraft can be made to be more responsive, fly faster and perform aerobatics whilst still being forgiving of errors. Take some time to go over these lessons once again and practice the manoeuvres until you can do them perfectly.
Most importantly, do not be afraid to ask advice! Your instructor is an instructor because he has been flying for many years and has flown a lot of different models and knows a lot of advanced flying skills. He can go on to teach you to fly aerobatic manoeuvres and even prepare you for your GOLD WINGS!
Finally – please do not be tempted by that 2 meter wingspan pure-scale spitfire for your second model! You will not be able to fly it just yet!!!

Lesson Eight – Engine Failure

Learning Objectives

  • Land safely and in control following an engine failure
  • Respond to other emergencies
img07-300x225
didn’t pay attention to his instructor

 

Engine Failure

Otherwise known as the deadstick landing this lesson will teach you how to react when things go wrong.

If your engine fails in flight call out ‘deadstick’ to your fellow pilots so that you are given priority use of the runway

There is only one really important thing to remember if your engine fails and is taught to both model and full-size pilots alike:

FLY THE AIRCRAFT!

So many people think that just because the engine has stopped the aircraft is going to drop out of the sky.  This just is not true!  You still have wings and your trainer will glide better than most other models in the sky.  As part of the Bronze Wings you will be asked to simulate an engine failure and get the aircraft safely back to the runway.

  1. Usually part-way along the downwind leg of a normal circuit you will be told to cut the throttle
  2. Reduce throttle to idle and let the aircraft settle into a glide
  3. Do not try to hold the aircraft in the air, use your skills in the landing circuit and approach to judge when to make your turns to bring the aircraft around to the runway
  4. Land as normal
  5. That’s it!

All that is really different in an engine failure is you do not have the luxury of a go-around if you get the approach wrong.  It is always better to be a little higher than normal on your approach so you can carry the speed into finals and have plenty of time to land rather than falling short of the runway.  If you are a little too high simply hold the aircraft straight and let it settle into the long grass at the end of the runway.  Better that than pushing in down elevator and smashing into the hard runway!

If your engine cuts and you do not have enough time to complete the circuit first and foremost, fly the aircraft!  Get the model under control and then decide which is the nearest runway to land on that you can reach.  Judge your turn and altitude to bring the model down safely as soon as possible.  It may not be your best landing ever but if the model survives no one will argue!

Engine Failure after Take-Off

If you have just left the ground and your engine fails DO NOT TRY TO TURN.  Turning at such a low speed and altitude will almost certainly cause a tip-stall and you will crash.  Fly the model straight ahead and let it settle back into the long grass.  This way you will get to fly again that day.

Other Emergencies

Most other emergencies in R/C aircraft usually place the model out of our control.  This is often as a result of radio failure and is the reason why adequate pre-flight checks are so important.

The only situation we may be able to react to would be a partial airframe failure such as an aileron or wing detaching, or the fin or horizontal tail breaking – but again this is why we check these items before flight.  In these situations we can only hope to avoid injuring other people rather than saving the model.

  1. If it is safe and possible to continue flying – land the model as soon as possible
  2. In the event of a major failure (i.e. flying surface detachment), cut the throttle and pull in up elevator to stall the model

Pulling in up elevator to stall the model sounds like an extreme solution and it is.  In this case the model is uncontrollable so by cutting the throttle and stalling the model we are ensuring it slows down and falls to the ground vertically.  Unless you were flying over the pits at the time (which you never would be) there is minimal risk to others this way.

Lesson Seven – Procedure Turn

Learning Objectives

  • Be able to fly smooth left and right-hand procedure turns
  • Maintain a constant altitude throughout the manoeuvre
procedure-turn
procedure-turn

Procedure Turns

  • You will handle all take-off and landings

The procedure turn is a compulsory figure in the Bronze wings test.  It is designed so that the student pilot can demonstrate competent and accurate turning skills within a practical manoeuvre.

In real-life the procedure turn is as useful in model aviation as it is in full-size aviation.  It allows the pilot to fly a heading and then turn in the smallest possible area to return in the opposite direction along the same line.  This is particularly useful when trying to line up with the runway or a heading that will return you to the runway.

A procedure turn is made up of two turns:

  1. Fly along the runway centreline during a circuit
  2. At the end of the runway make a turn away from you through 90°
  3. Once this turn is complete, immediately make a turn through 270° in the opposite direction
  4. Exit the turn to fly along the runway centreline in the opposite direction to that from which you entered the manoeuvre

The key to the procedure turn is to make careful use of all controls to ensure the manoeuvre is flown at a constant altitude and that you enter and exit the pattern along the same line.

Lesson Six – Landing

Learning Objectives

  • Be able to land safely and under control
  • To fly ‘touch and go’ circuits
landing
landing

 

Landing

  • Your instructor will only intervene in an emergency

The art of landing an aircraft successfully take a bit of mastering as the key is to fly the aircraft to the ground and not into the ground!

Before starting your landing approach, be sure to let other pilots flying know what you are doing

By now you should have mastered the landing circuit and be able to fly the aircraft close to the ground along the runway centre line.  Once you have reached this point it is really just a matter of supporting the aircraft as the wing loses lift and it descends slowly to the ground.

  1. As you approach the runway close the throttle completely so the engine is only idling
  2. Only use the ailerons to keep the wings level, use the rudder to hold the aircraft straight along the runway
  3. As you cross the end of the runway – the threshold – you should be about 0.5 meters above the ground
  4. Try to hold the aircraft at this altitude by applying a little up-elevator – this is called flaring
  5. Only use enough elevator to support the nose of the aircraft, too much and you will start to climb and then stall
  6. As the aircraft slows further it will slowly descend the last 0.5 meters and touch down gently
  7. Use the rudder to keep the aircraft straight as it slows to a stop

Congratulations, if you are safely on the ground you have flown your first complete solo and there will probably be a lot of applause coming from behind you!

If at any time during the approach and landing you do not feel comfortable you can apply full power and climb back into the circuit.  Just because you have called a landing does not mean you have to land on that approach.

If you are going to abort your landing attempt call out ‘going around’ to let other pilots know what is happening

You will spend a lot of time practicing landing from different directions until you are comfortable with the approach and flare.  This is the time in the flight when your aircraft is at most risk of damage and it pays to be an expert at landing in all situations!

Touch and Go Circuits

Once you have mastered landing it becomes boring is every time you touch down you have to taxi back to the end of the runway to take-off again!

As you land the aircraft, immediately apply full power and let the aircraft pick up speed once more.  You can then take-off again within the length of the runway!

The important things to remember during touch and go circuits are:

  1. Let the aircraft build up enough speed to take-off as normal.  Do not let it ‘bounce’ back into the air too soon and cause a stall.
  2. Do you have enough room to speed up sufficiently to take-off?  If you do not then let the aircraft come to a stop.

Lesson Five – Landing Circuits

Learning Objectives

  • Be able to line up with the runway ready for landing
  • Recognise the correct time to begin descending in the circuit
  • Descend and slow the aircraft whilst turning safely towards the runway
approach
approach pattern for landing

 

Landing Circuits

  • You will handle take-off, your instructor will handle landings

There are two main components to the landing circuit and approach:

  1. The line-up with the runway
  2. The descent to the runway

You should practice the line-up first before you begin to worry about the descent.  This is easy to do and you should have it mastered already if you can fly smooth and accurate circuits in both directions.

Most landings are made on the main runway at the LMMAC field; that is the runway that runs left to right in front of the pilot’s box.  This is useful as we can use the electricity pylon directly in front of us as a guide when to begin our descent.

  1. At normal circuit height pull the throttle back to around 25% as you the aircraft passes over the top of the pylon
  2. Allow the model to lose height slowly, do not try to use elevator to force it down or hold the nose up
  3. If you are descending to quickly, apply a little power
  4. If you are descending to slowly, reduce power a little
  5. Once you flown past the end of the runway begin a slow wide turn onto your base leg
  6. Continue descending as you make another turn onto the runway centreline
  7. Let the aircraft continue descending towards the runway
  8. Once over the end of the runway, apply full power and climb the aircraft smoothly back up to circuit height – this is called going around

It will take some time for you to get used to your aircraft and how much throttle and space it needs to descend. Do not be tempted to push down on the elevator to lose height more quickly as this will cause the aircraft to speed up and you will not be able to land safely.

Most new pilots find that it is more difficult to judge the final turn once the aircraft is descending.  Practice this approach a lot until you have memorised the correct position and altitude for each stage of the approach.

Lesson Four – Take Off

Learning Objectives

  • Be able to hold a straight line on the runway during the take-off roll
  • Be able to take-off smoothly and climb safely to circuit altitude
img06
The first take off!

The Take-Off

  • Your instructor will handle all landings

Taking off with a model aircraft is really very easy, especially with a trainer aircraft as is will be designed to fly smoothly and to climb when certain airspeed is reached.

The most important aspect of the take-off is keeping the aircraft travelling in a straight line both on the runway and when it first becomes airborne.  For this reason we start this lesson by not taking-off!

Your instructor will let you keep control of the transmitter on the ground and ask you to taxi out onto the runway.

If another pilot is flying do not taxi out onto the runway until you are within the pilot’s box and have asked if the runway is clear for use – he may be about to land!

Once you are on the runway your instructor will ask you to taxi along the runway, using the rudder to keep the aircraft as straight as possible.  With each pass, try to get use a little more throttle so you can practice controlling the aircraft at take-off speed.

When you are ready, the instructor will ask you to line the aircraft up at the end of the runway pointing into wind.  Take-off is always made into wind so that we can get into the air at a slower ground speed and in a shorter distance.  Your instructor will explain the difference between air and ground speed as you are learning.

If another pilot is flying do not take-off until you have announced your intentions

  1. Once you are lined up and ready to go, increase throttle smoothly to full power
  2. Use the rudder to hold the aircraft straight as it gains speed
  3. Once the aircraft is about level with you on the runway, use a small amount of up-elevator to help the model ‘un-stick’ from the ground
  4. Keep full power applied and allow the aircraft to gain speed whilst climbing at around 20-30°
  5. Use the ailerons to keep the aircraft level as it climbs away from the runway
  6. Once you have reached a safe altitude begin to turn into the circuit, continuing to climb to circuit height
  7. Once at circuit altitude, pull back the throttle to maintain straight and level flight

You will find your trainer aircraft very easy to control on the ground and it will climb smoothly under full power.  The most important things to remember are to use rudder on the ground and aileron once airborne.

As most trainers are designed to climb under full power you may find you need little or no up elevator to climb to circuit height.  In fact, with some trainers you may need a little down elevator to stop the model from climbing to steeply!

Lesson Three – Stalling

Learning Outcomes

  • Have an understanding of what a stall is
  • Be able to recognise and react in a stall situation
  • Be able to avoid a stall

stall1 

Understanding the Stall

Look at the pictures above.  In the first image the wing has a smooth flow of air over its upper surface.  This smooth flow of air around the wing is what creates lift and keeps the aircraft in the air.

In the second picture we have started to pull the nose of the aircraft up.  This tilts the wing against the oncoming flow of air.  This is called changing the angle of attack of the wing.  As this happens the air flowing over the upper surface of the wing begins to lose its grip on the surface and does not follow the shape of the wing any more.  You may think this is what happens when we climb, but in actual fact in the climb we also increase thrust so the aircraft still penetrates the air as if it was travelling straight and level – as in the first picture.  A stall occurs when the nose is raised but we have insufficient power to climb.  In this situation the plane continues to fly straight and level only at a slower speed and with the nose raised.

In the third picture the wing is completely stalled.  The angle of attack is so great that air can no longer stick to the top surface of the wing and it breaks away, swirling around in small ‘eddies’.  When this happens the wing is no longer generating any lift and can no longer counteract the force of gravity, so the aircraft falls from the sky!

Reacting to a Stall

To learn to react to a stall your instructor will ask you to fly the following steps:

  1. Starting from a normal circuit, you will create a stall during the upwind leg
  2. At a safe height, close the throttle and start to pull back gently on the elevator to raise the nose a little
  3. Continue to raise the nose as the aircraft slows down
  4. Once a stall occurs the nose of the aircraft will drop sharply, keep the aircraft straight using the ailerons and centre the elevator
  5. Allow the nose to drop and apply full throttle
  6. As the aircraft gains speed, use the elevator to bring the nose up and regain straight and level flight
  7. Climb back to circuit altitude and continue to fly the circuit

This whole process will take no more than a few seconds and the aim is to keep the aircraft flying straight without dropping a wing and losing as little height as possible.

Avoiding the Stall

This lesson becomes important when you are flying slowly and close to the ground, i.e. just after take-off and just before landing.  Practice stalling at altitude so that you can recognise when you model is going to stall and how slowly you can fly before a stall occurs.

If you think a stall is going to happen, the methods to avoid it are simple:

  1. Let the nose drop a little back towards a level attitude
  2. Increase power

Practice flying close to a stall and then pulling out of it before the nose drops.  If you can recognise the signs and react before the stall occurs you should never be in danger of nose diving into the runway!

The Tip-Stall

A tip stall occurs when just one half of the wing stalls, causing the aircraft to tip violently to one side and enter a spiral-dive.  This occurs when an aircraft turns too tightly at too slow a speed, which most often when you are making the final turn towards the runway for landing.  For this reason you must always make sure that your slow turns are made as wide as possible with as little bank in the wing as possible – this will be covered in more detail when you learn to land.

Lesson Two – Figure '8'

Learning Objectives

  • Be able to fly accurate left & right-hand figure ‘8’ patterns
  • Maintain a constant altitude whilst flying in this pattern

figure-8 

Perfecting the Turns

  • Your instructor will handle take-off and landings

The figure ‘8’ pattern is not included in the Bronze Wings test but is a useful training tool as it will allow you to practice left and right-hand turns until you can make precise, constant level manoeuvres in any direction.  This pattern always starts and ends over the centreline of the runway with the crossover point in front of the pilot.

  1. From a normal circuit start an upwind leg over the centreline of the runway
  2. As you begin to fly up the runway, make a 90° turn away from you
  3. Once the aircraft is flying away from you, make a 90° turn back in the opposite direction of the first turn
  4. Continue turning through another 90° until you are flying back towards the end of the runway
  5. As you come around to face the runway continue to turn back onto the runway centreline but facing in the opposite direction to that from which you started the manoeuvre
  6. Instead of flying straight on, carry on turning away from yourself until you cross point 3 once more – completing the first 360° turn
  7. Now make a 180° turn to the left to come around and point back at the other end of the runway
  8. Complete the manoeuvre by flying the final 90° turn back onto the original runway heading
  9. Fly along the runway and continue into a normal circuit pattern

At first this simple pattern will seem nearly impossible to fly smoothly as the turns will be too tight, too loose or you will gain and lose a lot of altitude.  As you spend more time practicing however you will find that you must use a combination of aileron, elevator and throttle to fly an accurate figure ‘8’.

The most important thing to remember when flying the turns is that it is not simply a case of applying a certain amount of aileron and elevator and holding it there.  You would not turn a corner in your car this way and you do not turn an aircraft this way either!  Turning accurately requires you to master balancing the controls; making constant small adjustments to fly a nice smooth line.

Keep practicing this even once you have passed your Bronze Wings as it is the basis of flying every different type of radio control aircraft and every different kind of aerobatic manoeuvre!