Helicopter Flight Training: Lesson Plans for Students & Instructors with Questions Plus a Lot More

By Ron Newman

This book covers all the sequences required through to a commercial pilot licence, plus night flying and basic instrument flying.
Each lesson plan is designed to bring the student up to a high standard of proficiency, not just the minimum required standard.
Not only does it detail what should be taught, it details what the student can expect from each lesson, how to conduct themselves within that lesson, and at the end of each lesson there’s a number of revision questions, with answers at the end of the book.
For instructors, it gives an insight into how various sequences should be taught, what the instructor can expect from the student, and what they should expect from themselves.

• Language: English
• Publisher: BookBaby
• Release date: Mar 1, 2015
• ISBN: 9781483552927

Book preview

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003 - AN OVERVIEW OF WHAT A HELICOPTER IS

A helicopter consists of structural components, mechanical components, and aerodynamic components.

The structural components are the fuselage, tail boom, skids, etc.

The mechanical components are the engine, freewheel, main gearbox, tail rotor gearbox, drive shafts, flight controls, etc.

The aerodynamic components are the main rotor, tail rotor, vertical stabiliser and horizontal stabiliser.

In an aeroplane (a fixed-wing aircraft), the engine and propeller provide the thrust, the wings provide the lift, and various control surfaces provide the means of manoeuvring the aeroplane.

In a helicopter, the main rotor lifts, propels and controls the helicopter, and as everything, apart from torque control, emanates from the main rotor head of a helicopter, they’re far more responsive to control movements, and far more demanding of a pilot than an aeroplane. A recent survey stated that, of all the man-made machines, the helicopter is the most difficult (and the most satisfying) to operate.

The engine drives the main gearbox via a freewheel, and the main gearbox drives both the main rotor and the tail rotor.

The main rotor consists of two or more blades, each one being an aerofoil. An aerofoil is a device that’s shaped to produce more lift than drag when air strikes it at an angle, and it produces more lift (and drag) if either the speed at which the air passes over it, or the angle between the airflow and the aerofoil (the angle of attack), are increased within defined limits.

When the rotor’s brought up to operating RPM, its inertia is too great to allow the Rotor RPM (R/RPM) to be varied quickly enough for it to be an effective means of altering its thrust. Therefore the RPM’s held constant and the angle of the blades (the pitch angle) is varied to alter the amount of lift that each blade produces, and therefore the amount of thrust the entire rotor produces.

The pilot uses a collective lever and a cyclic control to vary the pitch angle of the main rotor blades as required.

The collective lever’s held in the left hand and moved up and down to increase or decrease the pitch angle of all the blades the same amount at the same time.

Raising the lever ‘collectively’ increases the pitch angle of all the blades, and lowering the lever ‘collectively’ reduces the pitch angle of all the blades. This increases or decreases the blade’s angle of attack, which varies the amount of thrust the rotor produces, and causes the helicopter to climb or descend.

The cyclic control’s held in the right hand and moves back and forth, left and right, or any combination of these directions.

Moving the cyclic increases the pitch angle of each of the blades every time they pass through a particular location around the rotor disk, and decreases the angle of the blades as they pass through a position that’s diametrically opposite. The direction of cyclic movement determines at which point in the rotor’s travel the pitch angle of the blades are increased and decreased. When the cyclic’s moved, the rotor disk tilts in the direction of cyclic movement, which causes the helicopter to move (accelerate) in that direction.

When the collective’s raised and the pitch angle of all the blades is increased, the rotor requires more power to maintain the required RPM. This increase in power is achieved by a ‘throttle correlation cam’ that automatically opens the throttle when the collective’s raised, and decreases the throttle opening as the collective’s lowered. If this power change isn’t exactly what’s required, the RPM will change slightly and the pilot must twist the throttle control, which forms the ‘handle’ for the collective, in order to make minor adjustments to the engine’s throttle opening in order to ‘fine tune’ the engine RPM.

Some of the more recent piston engine helicopters have a ‘governor’ fitted that automatically varies the throttle opening to do this ‘fine tuning’ in order to maintain a constant RPM.

As previously stated, the main rotor gearbox drives both the main rotor and the tail rotor, and as the main rotor RPM is kept constant, it therefore follows that the RPM of the tail rotor must also be constant. Therefore, the only way to vary the thrust of the tail rotor is to vary the pitch angle of the tail rotor blades.

This is achieved by the pilot moving the anti-torque (tail rotor) pedals with his feet. These pedals are inter-connected, and moving one pedal forward causes the other pedal to move rearwards. Pushing the left pedal forward causes the nose of the helicopter to turn to the left (yaw left), and pushing the right pedal forward turns the nose to the right (yaw right).

When the engine’s driving the rotor, there’s a tendency for the rotor to stand still and the helicopter to rotate in the opposite direction (for every action there’s an equal and opposite reaction). This torque reaction is opposed by the thrust from the tail rotor and therefore, whenever the engine power (rotor torque) is varied, the tail rotor thrust must be varied accordingly.

This is a very basic description of the helicopter components and their primary uses; some of these principles will be expanded upon in later discussions.

004 - HELICOPTER SAFETY

Safety commences with the Daily Inspection (D.I.) prior to the first flight of the day, and the pre-flight inspections before subsequent flights.

I’m not going to go through the inspection procedures here as they’re adequately explained in the helicopter Flight Manual (sometimes called the Pilots Operating Handbook, or POH), and until you’re completely familiar with the procedures, you should carry the Flight Manual (or a copy of the inspection procedures) with you as you conduct the inspection.

If you’re not sure about anything you see, or not quite sure what to look at, ask someone. As a student, you’re not expected to know everything, and if you don’t ask, you’ll never know.

The next step in safety is the engine start and rotor engagement procedures, and once again, I’m leaving this to your Instructor and the Flight Manual for the aircraft you’re flying. It’s vital that you understand what you need to do, in what order to do it, and why you’re doing it. Once again, don’t be afraid to ask someone, there’s no such thing as a stupid question, particularly if it relates to safety. Unfortunately, there are stupid answers, and if you get one, don’t be afraid to tell them (politely) that you’re in the learning phase of your career, and you’re not sure what they meant so could they please explain it a different way.

All students and passengers must be familiar with the use of seat belts, headsets and door latches.

Before you go solo, you should know all the procedures and limitations relating to the helicopter type you’re flying, and why those limitations are imposed.

SEAT BELTS

Seat belts must pass closely over your body and mustn’t be twisted.

The lap belt must always pass across the lap as low down as possible, i.e. - over the hip joints and not across the abdomen. Pregnant women should wear it across the hips and below the baby.

The shoulder belt section should be routed across the middle of the appropriate shoulder and pulled tight against the upper body. On no account should it be routed across the neck or under the arm.

Don’t route any of the belt straps across sharp or fragile objects located on or in clothing, e.g. - spectacles, pencils, keys, etc.

When a shoulder harness is being fitted, the lap belt should be adjusted first, and the buckle should be in the middle to ensure the shoulder harnesses take the load evenly.

In the event of an impending crash, there may not be time to re-adjust safety harnesses, so make sure you and your passengers have them adjusted correctly before take-off.

DOORS

The doors must be securely latched before take-off, and all passengers must be familiar with the method of opening their door.

HEADSETS

The last thing you want is to have the headset start slipping as you’re half-way through a take-off, so take some time to fit it correctly. This is important for safety, comfort, and optimal noise reduction, and should be done as follows:-

•   As you put the headset on, adjust the headband so its padding rests on the flat fore & aft section on the top of your head, and the ear-cups are completely surrounding your ears so that you feel an even pressure all around each ear (the flat part’s there specifically for people that wear headsets, so make use of it).

•   Run one finger under the ear cushions and feel where your ear is in relation to the cushion.

•   The top of your ear should be just clear of the cushion, and your earlobe should be within the cup.

•   The cushion should not be pressing on any part your ear.

MOVEMENT AROUND THE HELICOPTER

The most dangerous part of the helicopter on the ground is the tail rotor, and the following procedures for operating around a helicopter must be followed at all times, regardless of whether the rotors are turning or not.

As a pilot, it’s very important that you watch the position of the rotor disk when running on the ground to ensure the disk is level in order to ensure maximum clearance over the safe entry arc.

Never approach the helicopter from the rear, you should approach between the 2 o’clock and 10 o’clock position in relation to the front of the helicopter. In some helicopters, such as the Sikorsky S-76, the rotor disk is quite low at the front, so they have different safe approach paths.

If you need to go from one side of the helicopter to the other, always remain close to the helicopter and go around the front, not the rear, and not under the tail boom. Make sure you don’t touch the pitot head as you pass, if pitot heat’s on, it’ll burn your hand badly.

When approaching a helicopter with a pilot at the controls, stand between the 2 and 10 o’clock position, clear of the rotor disk and wait until you have a signal from the pilot that you can approach the helicopter. This signal will normally be in the form of ‘thumbs up’.

Whenever you’re walking under the rotor disk, always duck your head and lean forward, keeping your eyes up and maintaining eye contact with the aircraft and the pilot.

Never raise your hands above your head when around the helicopter.

If you’re wearing a hat, either take it off, or put your hand on your hat to ensure it isn’t blown off by the rotor downwash.

Never throw anything when around or near a helicopter. There have been many accidents caused by people throwing things, such as keys and tools into the rotor while attempting to pass them to someone else.

Always carry long objects horizontally below the waist, preferably with two people.

YOU SHOULD GET INTO THE HABIT OF FOLLOWING THESE PROCEDURES WHETHER THE ROTORS ARE TURNING OR NOT..

005 – STARTING THE ENGINE

Before entering the aircraft, conduct a thorough pre-flight inspection in accordance with the manufacturer’s specifications, and make sure there are no blade tie-downs fitted. I’ve heard of a Jet Ranger being started with the tie-down still on. The strain on the tie-down eventually broke the strap, and the rate of acceleration that followed tore the main gearbox and main rotor out of the helicopter.

Because each helicopter has different starting procedures (even if they have the same engine), the actual procedures won’t be discussed here, they’ll be discussed by your Instructor in relation to the helicopter you’ll be flying.

The Flight Manual will have an engine start checklist for that helicopter, and this should be used for all starts until you’re completely familiar with the start procedures.

The procedures discussed here are basic to all helicopters and engines that are used for basic training purposes.

If a ground power unit or battery cart’s to be used for starting the engine, it must be checked to ensure it’s of the correct voltage. Modern light aircraft usually have either 12 or 24 volt systems, and using the wrong voltage can cause major damage.

The normal procedure is to start the engine with the radios and other avionics switched OFF to ensure the sudden drop in voltage as the starter motor’s engaged, and the sudden rise in voltage when the starter button’s released doesn’t cause voltage spikes in these sensitive systems.

Before starting a helicopter engine, make sure the surrounding area is free of persons, and any item that could be moved by the rotor wash after the rotor’s engaged.

Check and re-check the throttle’s in the correct position for starting the engine, and keep one hand on the throttle as you depress the starter button.

As soon as the engine starts, check that the oil pressure’s rising. If the engine’s cold, the oil pressure may be above the red line; this is normal as long as it returns to within the green arc when the oil temperature reaches its green arc.

STARTING A COLD ENGINE

Before activating the starter motor, prime the engine in accordance with the Flight Manual to richen the mixture for starting.

This may involve opening and closing the throttle several times to allow the accelerator pump within the carburettor to pump fuel into the inlet system, or by operating a manual or electric priming pump to inject fuel directly into the induction system.

STARTING A HOT ENGINE

The procedure for starting an engine with a carburettor is much the same for either a warm or hot engine.

Engines that are fuel injected have very small lines carrying the fuel from the fuel injector unit to the individual cylinders, often over the top of the cylinders, and the fuel in these lines can become overheated after the engine’s been shut down for some time. This can create air bubbles in the high point of the fuel lines, which can prevent the fuel from flowing through that line (or possibly all the lines).

Fuel injected engine’s always have an electric fuel pump, and if the engine doesn’t start readily without priming, you may need to use this pump to ensure these air bubbles aren’t obstructing the passage of the fuel to the cylinders.

Unfortunately this may flood the engine, and if so you’ll need to use the procedure for starting a flooded engine.

STARTING A FLOODED ENGINE

If you suspect flooding’s the cause of hard starting, you can either wait for approximately 5 minutes to allow the fuel to evaporate and drain away (there’s usually a spring loaded drain in the plenum chamber surrounding the sump that opens when the engine’s shut down and closes when it starts), or adopt the following procedure.

•   Switch the ignition OFF. This isn’t possible if the helicopter’s fitted with a combined ignition/starter switch (R-22).

•   Turn the fuel pump OFF (if fitted).

•   Set the mixture control to IDLE CUT-OFF.

•   Open the throttle fully.

•   Crank the engine through several revolutions with the starter motor to clear the induction system of excess fuel.

You’d then start the engine in the normal manner without priming, but it may be necessary to open the throttle a little more than usual during this procedure, and I emphasize little. If you open the throttle during the start procedure, be prepared to retard the throttle immediately the engine starts.

After 5 or 6 attempts, let the engine stand (with the throttle open to ventilate the induction system) for at least 5 minutes before attempting another start. If you continue cranking without allowing the starter motor to cool down, you’re likely to overheat and melt the electrical windings within the starter motor.

CHECKS AFTER STARTING

Starter warning light – OUT (if fitted).

Oil pressure – Sufficient. It may be above the maximum pressure (red) line if the engine was cold; if so, check it’s back within the acceptable range when the oil temperature reaches its minimum red line.

RPM – Set the recommended idling RPM to ensure adequate cooling and lubrication. The cylinder walls are lubricated by splash, and need at least 1,000 RPM to ensure an adequate amount of oil is splashed onto the cylinder walls by the rotating crankshaft.

Ammeter – Showing a charge.

ENGINE FIRE ON START-UP

If a fire starts while starting the engine, the following procedure will usually put the fire out without damaging the engine.

•   Continue cranking the engine.

•   Mixture control to IDLE CUT-OFF.

•   Fuel pump OFF (if fitted).

•   Throttle OPEN to increase the airflow through the engine and purge the unburned fuel out into the exhaust system (which is designed to handle high temperatures).

•   Fuel valve OFF.

It’s vital that you continue to crank the engine. If you release the starter button, the fire’s likely to move back into the induction system where the fuel is (and it’s not designed for high temperatures). This would almost certainly destroy the engine, and possibly the entire aircraft.

006 - HOLDING THE CONTROLS

Because of the extreme sensitivity of the cyclic control, your ability to fly smoothly relies on your ability to make minor movements on this control. The smaller the muscle group you use, the more sensitive the movement is, so the most delicate control movement will be with finger pressures, and as you move up in the muscle group to the wrist, the forearm, and finally the shoulder, the coarser the control movements will become.

Although the collective and the pedals are nowhere near as sensitive as the cyclic, the same principle applies, the smoother the control movement, the smoother the helicopter’s response.

One of the most important points to help you relax enough to control the helicopter smoothly, is the way you sit and the way in which you hold the controls. You need to rest your right forearm on your leg, so that you can move the cyclic with finger pressures, and not arm movements. This is the only way in which you’ll ever be able to reach your full potential as a helicopter pilot. Remember, the helicopter does what you tell it to do via the controls, and if you move the controls coarsely, the helicopter will respond coarsely. If you want the helicopter to ‘float like a butterfly’ and do precisely what you want, you must be precise, but gentle, with the control movements.

These instructions on how to hold the controls are based on a person of average height, and may need to be modified for other people.

SEATING POSITION

You should sit comfortably with your back resting against the seat, and your head upright in relation to your body. This puts your head in line with your spine, and you should be able to nod your head up and down without feeling a strain in the side of your neck, regardless of whether you’re flying straight and level, or turning (try tilting your head to one side and then nod your head up and down). If you still don’t believe me, put a couple of books under your chair legs on one side and try sitting there for a while, you’ll soon see (feel) why it’s better have the aircraft level and you sitting upright in relation to the seat.

Sitting comfortably also reduces the chances of back problems in the long term, and makes you more capable of doing a long day’s work without getting excessively tired.

FLYING BY FEEL AND OUTSIDE REFERENCE

These explanations assume you’re sitting comfortably as described above.

If you sit correctly, when the aircraft’s in a 30o bank angle, your eyes will be angled 30o from the horizon, which gives you the correct impression of the bank angle, whereas if you lean to one side, your eyes will be giving you a false indication of the angle of bank (or telling you there is one when there isn’t - or there isn’t one when there is).

If the helicopter’s flying left skid low, your upper body will be trying to fall over to the left, and you’ll feel the left side of your back (just under your left shoulder) pushing into the seat as it tries to keep you upright (lean to the side while your reading this and you’ll see what I mean).

When you feel this, if you press just enough left pedal to remove this pressure and make your back feel comfortable, you’ll find the balance ball’s very close to being in the middle (vice versa with a right bank angle).

If the balance ball’s out to the left, you’d turn the nose to the left in order to bring the ball back to the middle, so do the same if your upper body’s trying to move out to the left (in reality, you’re using your upper body as a balance ball). Don’t try and fly by instruments and ‘stand on the ball’ as often stated, look at your reference point out front and turn the nose slightly to the left until your back feels comfortable, and then cross-check the balance ball to see if you’ve turned the nose the correct amount.

This works regardless of whether you’re making a power change, flying straight and level, in a turn, or any combination of these. If there’s no pressure on your back to keep you upright in relation to the seat, your back must be at right angles to the floor of the helicopter, and you’re in balance (or very close to it).

Once you master this, the balance ball becomes a ‘cross reference’ only, regardless of whether you’re VFR or IFR.

Remember, your passengers don’t know whether you’re a good pilot or not, they only know whether or not they felt comfortable during the flight, and as you very rarely fly with your peers, this is one of the main sources of feedback that goes toward developing your reputation as a pilot.

PEDALS

With your heels resting on the floor, place your feet on the pedals in such a manner that your feet are at right angles to your shins, i.e. - your ankles are in their natural position, and if you didn’t have your shoes on, your toes would roll over the top of the pedals.

You can then use ankle movements for small, temporary pedal movements, and slide one foot forward and one foot back for larger or longer term pedal movements.

With your legs in this position, rest your right wrist on your leg, and make sure your wrist isn’t bent. This will ensure a line running from your elbow to the joint of your thumb and forefinger is as straight as possible, and it’ll keep the back of your forefinger approximately parallel with your forearm.

CYCLIC

Once the rotor’s engaged, the helicopter’s in a ‘flying’ state, and the cyclic must be controlled at all times.

If you hold the cyclic as shown here, and control it with the following movements, you’ll have full control over the helicopter’s attitude with finger pressures only (please forgive the grease under my thumb-nail, I must have been doing some maintenance before setting up for this photo).

Right cyclic - Apply pressure with your thumb, which will push the cyclic into the fleshy part of your forefinger (2).

Left cyclic - Apply pressure with the fleshy part of your forefinger (2), which will push the cyclic into the fleshy part of your thumb.

Aft cyclic - Flex your finger (or fingers) backwards from the knuckle joint (1).

Forward cyclic - Apply forward pressure with the wedge that’s formed between your thumb and forefinger (3).

One way of determining how firmly to grip the cyclic is to imagine you’re holding a small bird firmly enough to prevent it escaping, but not firmly enough to harm it.

By no means is this the only way you can control the helicopter, but it’s definitely the smoothest, you won’t see a surgeon holding a scalpel with a vice-like grip, or if you do, go somewhere else for the operation.

Imagine putting a ball bearing on a glass table-top and trying to move it 1 mm by holding your arm out and pushing it with your unsupported arm and finger, and then imagine resting your hand on the table-top and moving the ball bearing with a finger movement. This is the equivalent of using either finger pressures or arm movements to make a minor movement of the cyclic.

If you practice these movements as you watch the attitude change, you’ll be surprised how smooth your flying becomes (your eyes are telling your hands what to do, and how fast to do it). An IFR pilot would never adjust the attitude unless they were looking at the artificial horizon to see when they’d changed the attitude enough, so why wouldn’t a VFR pilot look at the real horizon when they’re changing the aircraft’s attitude.

The basic position of the cyclic alters quite a bit from the hover through to cruise speed, and you’ll have to move your wrist along your leg as this occurs in order to ensure you can still manipulate the cyclic in this manner.

Most helicopter maintenance manuals require a specified amount of cyclic friction to be present when the friction control is backed off completely. This is an engineer’s adjustment, and the helicopter may or may not be fitted with a friction control to allow the pilot to adjust the friction to a setting above this pre-set amount of friction.

COLLECTIVE

Hold the collective in your left hand, firmly, but not too tight, with your thumb wrapped around the throttle (not lengthwise along it).

Because the collective isn’t moved anywhere near as often as the cyclic, you’re far better off having a moderate amount of collective friction applied so you have to move the collective against the friction. This will ensure you don’t move the collective unintentionally as you move the other controls.

The maximum amount of collective friction that you can apply should be set by the engineers to ensure you can still lower the collective with full friction applied if the need arises.

007 - ALTERNATE SPELLING

In the English language, there are two main styles of spelling, English UK and English US.

Because I live in Australia, and we use the English UK style of spelling, this E-Book, my 2 printed books HELICOPTERS WILL TAKE YOU ANYWHERE and THE TECHNICAL, AERODYNAMIC & PERFORMANCE ASPECTS OF A HELICOPTER as well as my Online Aviation Theory website www.OnlineAviationTheory.com all use the UK style of spelling.

To alleviate the problems for people who use the US style of English having to search for a word in this e-book, I’ve compiled the following list of alternate spellings of the main aviation terms in use, with the ones I’ve used in bold type.

Aerofoil - Airfoil

Aeroplane - Airplane

Analyse - Analyze

Aluminium - Aluminum

Carburettor - Carburetor

Centre - Center

Colour - Color

CFI (Chief Flying Instructor) - CFI (Certified Flying Instructor)

Disk - Disc

Defence - Defense

Labour - Labor

Recognise - Recognize

Synchronise - Synchronize

Stabiliser - Stabilizer

Track - Course (Mainly to do with VORs)

01 - EFFECT OF CONTROLS

PREAMBLE

Don’t expect too much from this, your first lesson. But one thing you must get from this lesson is how to sit, how to adjust your seat belt and headset, and how to hold the controls. If you don’t get these things right at this stage of your training, you might never get them right.

The co-ordination required to fly a helicopter smoothly can only be learned by constant practice. The more you understand about the function of the controls, the sooner you’ll be able to anticipate the secondary effects of the control movements you’re making, but the development of this anticipation takes many hours of practice.