turboprops tng manual.pdf

8/20/2019 TURBOPROPS TNG MANUAL.pdf

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FTG Training Division Turboprop Operations Manual

Turboprop Operations Manual

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Foreword

The primary intent of this manual is to guide you through the FTG regional turboproptype rating exam. You have to have basic knowledge about (flight simulator) flying

and FTG operations. Please work through the resources you can find at the trainingdepartment of your FTG VA.

There are some obvious differences between turboprop and jet aircraft. Turbopropscan’t fly as fast as jets. And they can’t fly as high as jets. But they don’t need asmuch fuel as jets do.On short distance routes they are simply cheaper to operate, because on these shortlegs jets can’t really play their speed advantage trump. So now that we know whyturboprops are in service, let’s see what a pilot has to know about them to fly them.

I have put quite some time into writing this manual, and I do not want it to be wastedtime. That would be the case if you consider this manual useless and it is no help toyou for whatever reasons. So I would very much appreciate if you contact me in caseyou find anything completely confusing, too superficial or missing.So if you have any questions, suggestions or criticism please contact me.

Happy and successful learning

Raffael [email protected]

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1. How does a turboprop engine work?

A turboprop engine basically consists of a propeller which is driven by a jet engine.To understand hoe a turboprop works, we’ll first have a look at what a jet engine is

and how it works. Here we go:

Thrust is the force which moves any aircraft through the air. Thrust is generated bythe propulsion system of the aircraft. Different propulsion systems develop thrust indifferent ways, but all thrust is generated through some application of Newton's thirdlaw of motion: For every action there is an equal and opposite reaction. Imagine youstand at the back of a small boat and throw a large stone backwards off the boat. Theboat will move in the opposite direction from where you threw the stone. You have just generated thrust. Newton also called this “action est reactio”.

Now where is the link to an airplane engine? It “throws” air instead of stones,meaning it gives an amount of air a high speed. As a reaction, the engine with theaircraft attached to it moves into the opposite direction of the air which went throughit. The air can either be moved by a jet engine or a propeller.

This page shows computer drawings of four different variations of a gas turbine or jetengine. While each of the engines are different, they share some in common. Each of

these engines have a combustion section (red), a compressor (cyan), a turbine(magenta) and an inlet or intake and a nozzle (grey).The compressor, burner, and turbine are called the core of the engine, since all gas

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turbines have these components. The core is also referred to as the gas generator since the output of the core is hot exhaust gas. The gas is passed through a nozzleto produce thrust for the turbojet, while it is used to drive the turbine (green) of theturbofan and turboprop engines. Because the compressor and turbine are linked bythe central shaft and rotate together, this group of parts is called the

turbomachinery.

Most modern passenger and military aircraft are powered by gas turbine engines,which are also called jet engines. The first and simplest type of gas turbine is theturbojet. How does a turbojet work?

Large amounts of surrounding air are continuously brought into the engine inlet or (InEngland, they call this part the intake, which is probably a more accurate description,since the compressor pulls air into the engine.) We have shown here a tube-shapedinlet, like one you would see on an airliner. But inlets come in many shapes and sizesdepending on the aircraft's mission. At the rear of the inlet, the air enters thecompressor. A compressor is like an electric fan. We have to supply energy to turnthe compressor. At the exit of the compressor, the air is at a much higher pressurethan at the intake. In the burner a small amount of fuel is combined with the air andignited. Leaving the burner, the hot exhaust is passed through the turbine. Theturbine works like a windmill. Instead of needing energy to turn the blades to makethe air flow, the turbine extracts energy from a flow of gas by making the blades spinin the flow. In a jet engine we use the energy extracted by the turbine to turn thecompressor by linking the compressor and the turbine by the central shaft. Theturbine takes some energy out of the hot exhaust, but there is enough energy leftover to provide thrust to the jet engine by increasing the velocity through the nozzle.

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Propeller-Produced Thrust

For the forty years following the first flight of the Wright brothers, airplanes usedinternal combustion engines to turn propellers to generate thrust. Today, mostgeneral aviation or private airplanes are still powered by propellers and internal

combustion engines, much like your car engine. The engine takes air from thesurroundings, mixes it with fuel, burns the fuel to release the energy in the fuel, anduses the heated gas exhaust to move a piston which is attached to a crankshaft. Inthe automobile, the shaft is used to turn the wheels of the car. In an airplane, theshaft is connected to a propeller.

Propellers as Airfoi ls

The propeller acts like a rotating wing creating a lift force by moving through the air.For a propeller-powered aircraft, the gas that is accelerated is the surrounding air thatpasses through the propeller. The air that is used for combustion in the engine

provides very little thrust. Propellers can have from 2 to 6 blades. A cut through theblade perpendicular to the long dimension will give an airfoil shape. Because theblades rotate, the tips move faster than the hub. So to make the propeller efficient,the blades are usually twisted from hub to tip.

Other Engines Drive Propellers

After World War II, as jet engines gained popularity, aerodynamicists used jetengines to turn the propellers on some aircraft. This propulsion system is called aturboprop. A C-130 transport plane is a turboprop aircraft. Its main thrust comes fromthe propellers, but the propellers are turned by turbine engines. The human-poweredaircraft of the mid 80's were also propeller-powered, but the "engine" was providedby a human using a bicycle gearing device. Currently NASA is flying a solar-powered,electric engine aircraft that also uses propellers. Propeller-powered aircraft are veryefficient for low speed flight. But as the speed of the aircraft increases, regions ofsupersonic flow, with associated performance losses due to shock waves, occur onthe propeller. So propellers are not used on high speed aircraft.

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Many low speed transport aircraft and small commuter aircraft use turboprop propulsion. The turboprop uses a gas turbine core to turn a propeller. Propellerengines develop thrust by moving a large mass of air through a small change invelocity. Propellers are very efficient and can use nearly any kind of engine to turnthe prop. In the turboprop, a gas turbine core is used. How does a turboprop enginework?

There are two main parts to a turboprop propulsion system, the core engine and thepropeller. The core is very similar to a basic turbojet except that instead of expandingall the hot exhaust through the nozzle to produce thrust, most of the energy of theexhaust is used to turn the turbine. There may be an additional turbine stage present,as shown in green on the diagram, which is connected to a drive shaft. The driveshaft, also shown in green, is connected to a gear box. The gear box is thenconnected to a propeller that produces most of the thrust. The exhaust velocity of aturboprop is low and contributes little thrust because most of the energy of the coreexhaust has gone into turning the drive shaft, and with it the propeller.

Because propellers become less efficient as the speed of the aircraft increases,turboprops are used only for low speed aircraft like cargo planes. A variation of theturboprop engine is the turboshaft engine. In a turboshaft engine, the gear box isnot connected to a propeller but to some other drive device. Turboshaft engines areused in many helicopters, as well as tanks, boats, and even race cars in the late1960's.

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2. Flying Turboprop Aircraft

Turboprop aircraft are the first stepping stone for many professional pilots at thebeginning of their career. Many pilots consider turboprops to be optimal introductoryaircraft to airline flying. Things aren’t going quite as fast as on jets; you don’t have tobother with long range flight planning or multiple day rotations. So many airlinesassign new pilots to their turboprop fleet and let them gain their first amount of lineflying experience.

Flying turboprops is different. It’s different from flying a Cessna Skylane, and it’sdifferent from flying a 737. Not necessarily harder, just different.

First of all, we will have look at how a propeller works and drives your aircraft.Small GA aircraft like the Cessna Skylane have fixed pitch propellers. A propeller’spitch is the angle of the blade related to its plane of rotation. A low pitch means the

blade’s axis points at the direction the propeller is rotating, i.e.to the side of the aircraft. A high pitch means that the axis ofour propeller points the direction the propeller is moving theaircraft. Thus with a pitch of 90° the propeller blade’s axis isparallel to the axis of the (imaginary) line along which theaircraft is moving. This means the blade’s axis is right-angledto its plane of rotation. If this angle is fixed, we speak of a fixedpitch propeller. The pitch is then one which suites all needsbest, for it cannot be changed during flight.

The blade angle of a variable pitch propeller can be changed, either on ground or

during flight. But why should one want to do that?

Because the optimal pitch changes during the course of a flight. If we compare thepropeller engine to the engine of a car, the pitch angle would have its counterpart inthe gears of the car engine.If you want to drive up a steep hill, you would shift into a low gear, so that the enginecan transmit as much power as possible to the wheels. You do the same in anaircraft by setting a low propeller pitch (also called fine pitch). The torque needed toturn the propeller is low now, because the turning propeller does not create a lot ofdrag; so the engine turns the propeller fast. Your engine then can deliver a lot ofpower to the propeller during takeoff or go-arounds.

As the slope you are driving up becomes less steep, you shift into a higher gear, asyou can’t go very fast in a low gear. A lot of fuel is also used when driving in a lowgear, as your engine runs at a high RPM.Same story again in an aircraft which is driven by a variable pitch propeller. Afterinitial climb, pitch is increased, what in turn increases the torque needed to turn thepropeller. That forces the engine to turn at a lower RPM. That allows us to fly fasterwhile burning less fuel. You can observe exactly the same in your car: shift up, theRPM drops and you can accelerate to higher speeds.

As we enter cruise flight (or driving up the highway), we want our engine to produceas much power as possible to go as fast as possible while burning as little fuel as

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possible. Time to shift into the highest gear then. You also release the gas pedal assoon as you have reached your desired cruise speed.

So, in the air you increase thepropeller pitch even further (to

a position called coarse pitch)at cruise flight and you pullout as much power aspossible to hold your cruisespeed. The torque needed toturn the propeller is now quitehigh, as the propellerproduces high drag, but eachrevolution of the now highpitch propeller takes you wayfurther than one of o low pitch

propeller would. Your enginesrun at low RPM, thus theyburn only small amounts offuel. The picture at the rightmight help to visualize this.

To make a (turbo)prop pilot’s live easier, and make learning even more confusing,the constant speed propeller was developed. It basically manages pitch settingautomatically; the pilot only has to set the RPM he wants the propeller to turn at.

A constant-speed (RPM) propeller system permits the pilot to select the propellerand engine speed for any situation and automatically maintain that RPM undervarying conditions of aircraft attitude and engine power. Thereby permitting operationof propeller and engine at most efficient RPMs. RPM is controlled by varying the pitchof the propeller blades. When the pilot increases power in flight, the blade angle isincreased, the torque required to spin the propeller is increased and, for any givenRPM setting, aircraft speed and torque on the engine will increase. For economycruising, the pilot can throttle back to the desired cruise conditions and decrease thepitch of the propeller, while maintaining the pilot-selected RPM.

A full-feathering propeller system is normally used only on multi-engine aircraft. If one of the engines fails in flight, the propeller onthe idle engine can rotate or windmill, causing increased drag. Toprevent this, the propeller can be feathered (turned to a very highpitch), with the blades almost parallel to the airstream. Thiseliminates asymmetric drag forces caused by windmilling when anengine is shut down. A propeller that can be pitched to thisposition is called a full-feathering propeller.

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To sum things up, with a constant speed propeller system (all turboprop airliners useconstant speed propellers!):

Increasing engine power at any given RPM means that propeller pitch andtorque required to spin the propeller are increased, so that the RPM remainsconstant.

Decreasing engine power at any given RPM means that propeller pitch andtorque needed to spin are decreased as well, to hold the commanded propellerRPM.

A glance at a turboprop panel

Turboprops have other gauges and levers in their cockpits than jets or piston engine

aircraft have. We’ll now have a look at them.

• Torque indicator It basically tells you how much power from the turbine is transferred to thepropeller. It’s calibrated in percent, where 100% is the upper limit which shouldnot be exceeded. Torque settings for each phase of a flight are published inthe AOM (Aircraft Operation Manual). They have to be varied with speed,altitude, air temperature and, of course, with the type of aircraft.

• IIT (Interstage Turbine Temperature) Indicator Tells you when your engine is getting too hot. Don’t exceed the limits, as that

would kill your engines within very short time.

• Propeller RPM Indicator, Np Speed the propellers are turning at. It either shows a percentage (100%=Max)or an absolute number. This speed is set by the pilot using the conditionlevers. Prop speed also has to be changed during the course of a flight, but it’snot changing with altitude or temperature, rather with the flight phase. So thereis a setting for takeoff and one for climb and for cruise. The settings are alsopublished in the AOM. And again, stay below the red line.

• Gas Generator RPM Indicator, N1, Ng, NL Indicates gas generator RPM as percentage. Is set by using the power levers.The power lever also affects the torque setting.

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• Power Lever Sets N1 and torque. Ifmoved forward at aconstant Prop RPM, N1

and Torque will rise. I.e.advancing means morepower. Can be movedback through the idleposition. Behind the idleposition the power leverdirectly commands thepropeller blade pitch.The first part of thebackward movementputs the blades in a very

shallow angle where theyproduce little or no thrust. This is called the Beta Range, and it’s used duringground movement to prevent overspeeding.If moved back even further the power lever commands the blades into reverseangle, where they produce thrust directed to the front of the aircraft. This iscalled the Prop Reverse Range and it’s used to slow down after landing andduring taxi.

• Condition Lever The Condition Lever commandsProp RPM. The RPM set by thePilot using CL is held constantby a hydraulic mechanismwhich varies the blade angle(this setup is called “ConstantSpeed Propeller”, because thepropellers always turn at thecommanded speed, regardlessof the power setting).Exceptions to this ”always thesame speed behaviour” are the

aforementioned Beta & ReverseRange and the FeatherPosition. In this position theblades are at a neutral angle and produce neither thrust nor drag. This is usedin case of an in flight engine failure to prevent the no-more-by-an-engine-turned-propeller from producing too much drag. The pilot can command theblades manually into the feathered position by pulling the condition lever allthe way back. If he pulls it back through a lock even further, fuel flow to theengine is cut off.

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• Prop Lever Some turboprop aircraft have athird lever in the cockpit, theProp Lever. In this case theprop lever commands prop

speed and manual feathering,and the CL commands the idlespeed of the gas generator andthe fuel cut-off. The conditionlever has then to be set to a“low idle” position most of thetime. E.g.: In the Beech King Air350 the low idle positionenables N1 values form 62% to104%. In the high idle position itenables N1 values from 70% to

104%. That means in the lowidle position you have a wider N1 range available. That’s only if you can findthree different levers in your cockpit. If there are only two, they work asdescribed above.

Don’t wonder if your head is smoking right now, here is a short summary of theabove:

You set N1 and Torque by using the power levers. Pull the PL back through idle andyou make your props produce less thrust, as you now control propeller blade angledirectly. Pull PL back farther and you will slow down as you are now reversing.You set Propeller RPM by using the Condition Lever. You don’t have to care aboutyour prop RPM anymore, as it will be held constant mechanically. Just set thedesired value, but don’t forget to change it according to your current stage of flight.Pull CL all the way back and you have feathered your propeller, which no produceszero thrust. Pulling it back totally cuts the fuel flow off, i.e. shuts the engine down.

To illustrate all that a little more we’ll quickly talk through a flight in a turbopropairliner, focusing on the handling of the control elements discussed above.

You will find your aircraft with engines shut down. That means PL will be in

idle position and CL in cut-off. As the cut-off position at the CL is behind thefeather position, you will always have feathered propellers if you shut theengines down. After finishing all the before start-up work (acceptance checks,establishing power supply, setting up FPL in FMC…) you follow the aircraftspecific procedures for starting up the engines. Finally you have to move theCL from cut-off into the feather position to establish fuel flow to the enginebeing started. It now should spool up.To start rolling move CL about halfway forward. Don’t move the PL, as nothingwill as long as you don’t move CL forward. Why? Right, because then yourpropeller is still feathered.During ground movement you should move your PL only between idle and

Beta Range, as turboprops have the tendency to behave like sports cars onground.

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SET CLs ABOUT HALFWAY FORWARD. MOVE PLs ONLY BETWEENIDLE AND BETA RANGE. THAT MEANS YOU ARE CONTROLLINGGROUNDSPEED WITH PROPELLER BLADE ANGLE ONLY.

When you turn onto the takeoff runway move CL all the way forward. Thenmove the PL gently forward up to the takeoff torque/N1 setting, whatever your AOM reads.

TAKEOFF IS ALWAYS EXECUTED WITH CLs FULLY ADVANCED; PLs ARE ADVANCED UNTIL TAKEOFF N1/TORQUE IS REACHED.

You can spare yourself from turning performance charts by simply advancingPL until N1 or Torque is about to enter the red zone on its indicator. Just don’texceed the limits.

After the initial climb flown at V2+5 up to 1500 ft AGL you reduce the rate ofclimb to gain speed, retract the flaps and pull CL back to set climb RPM (or just far enough to stay below the red line). You also pull back the PL to setclimb torque. During your climb to your cruising altitude you will have togradually pull back PL so that you don’t exceed climb torque. Climb torque willbe around 80% for most turboprops. Also keep watching ITT and N1 so thattheir limits (red lines) are not exceeded. When at your cruising altitude, pull PLas far back as possible to hold your cruise speed.

CLs ARE ONLY MOVED ONCE AFTER INITIAL CLIMB TO SET CLIMPPROP RPM. ALL OTHER ADJUSTMENTS ARE ONLY DONE VIA PLs.

When you begin your descent pull back PL as far as needed to hold yourdesired descent speed.

PROP FEATHERING OR MOVING BACK CLs ALL THE WAY WILL NOTSLOW YOU DOWN DURING DESCENT, AS THE PROPS DON’T PRODUCE ANY DRAG WHEN FEATHERED.

On final approach CL are again moved fully forward, so that you have enoughpower at hand if you have to execute a missed approach. Adjustments via

PLs.

AFTER TOUCHDOWN MOVE PLs BACK AS FAR AS POSSIBLE TO PUTTHE PROPELLER BLADES IN REVERSE ANGLE. LEAVE CLs INFORWARD POSITION.

When you are as slow as you want to be pull CL about halfway back andcontrol groundspeed with power levers between idle and beta range.

To shut the engines down move CL through the feather position into fuel cut-off position.

Many modern turboprop aircraft assist pilots to have the values set right throughpower management computers. This assistance can range from computer controlled

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bugs on the torque indicator which the pilot follows to fully automated thrustmanagement systems which manage optimal torque settings completely bythemselves. The ATR 72-500 for example has such a high degree of torquemanagement automation.In FS of course it depends on the panel you are using how much computer

assistance you will have available. Please study the manuals for your aircraft/panelcarefully so you can make the best use of features developed to assist you.If you don’t have any thrust management computer with you up there just stick to thepublished performance charts and keep all indicator needles out of their red zones.

Another peculiarity of turboprop aircraft is that they can drive backwards on groundby themselves, without the use of a pushback truck. How? Simply by putting the PLsinto reverse position, the engines won’t be damaged by doing this.You should use extreme caution when doing this, as you can’t see what’sgoing on behind your aircraft. Be very cautious with the use of thewheelbreakes when rolling backwards, as the aircraft will have the tendency to

flip onto its tail if it’s stopped too abrupt.

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3. Safety

As a pilot of an FTG Airline your primary concern should be safety. The safety of yourpassengers, of the plane and finally your own safety.

An aircraft that crashed because the crew hurried to be on time is of no use for yourcompany. Some chief pilots tend to forget that when your last flight arrived late onceagain. If you are asked for an explanation, do one of the following things:

If you were late because of circumstances you could not change, like heavy traffic,explain this to your chief pilot.If you were late because you made a mistake, try to identify the reasons for why youmade the mistake and never make it again.

But never ever get in a hurry to be on t ime. You will be in trouble sooner thanlater if you do so.

Countless investigations of aviation accidents and incidents show that a lot of themhappen because pilots got in a hurry, and thus putting themselves under greaterstress than they needed. Crews trying to get somewhere as quickly as possible tendto miss crucial checklist items, make miscalculations, misread minimum descentaltitudes and generally tend to take higher risks then crews who take a more relaxedapproach to the whole story.

In flight safetyThis term summarizes all actions taken by the crew of an airplane-pilots and cabincrew- in flight to keep their passengers safe. The following actions are to be taken onevery FTG flight:

• Below an altitude of 10.000ft AGL passenger signs have to be turned on. Always.

• If turbulences are anticipated or experienced passenger signs have to beturned on, regardless of the current altitude.

• At every waypoint of your flightplan check your fuel status. Did you use moreor less then planned? Does it look like you will run out of fuel before you reachyour destination? If this is the fact, immediately deviate to the next possiblealternate to refuel. Things like that happen. You could have miscalculated yourfuel needs, or “external” circumstances like the weather could have changedduring the course of your flight. A technical problem might also well be thereason why you needed more fuel than planned. There is one moment whereyou can take corrective actions to prevent ugly things from happening. Themoment when you recognize that you have less fuel than needed. The soonerthis moment occurs, the better, obviously. So have an eye on your fuel gauges

regularly. The moment you are approaching the largest meadow you couldfind with your engines off is too late. Definitely too late.

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• Check your position at every waypoint of your flightplan. Are you where youshould be? Even in times of FMCs your responsibility as a pilot is to get whereyou want, not where a faulty (or wrong programmed!) computer might want totake you to.

When to abort an approach

The pilot flying has the right and the obligation to abort an approach when he, forwhatever reasons, is not completely sure that a landing can be made safely. So evenif you just have a bad feeling about your current approach, go around, give yourself abreak, correct the reasons for your bad feeling and try again. However, a go aroundis mandatory:

• If you cannot see the runway at the Decision Altitude (DA) / Decision Height(DH).

• If you are not on a stabilized approach at 400ft AGL. Stabilized approachmeans being on LOC and GS if on an ILS approach; being aligned with therunway centreline and on GS indicated by visual aids like PAPI on a visualapproach; airplane configured for landing, landing checklist completed on anyapproach at 400ft AGL.That means that at 400ft AGL everything has to look like you are going to beable to land safely (if you are on an ILS approach you still have to wait if yousee the runway before DH/DA, but you must be ready to land at 400ft AGL).

• If ATC requests you to go around.

Ai rcraft ic ing

Icing is a great danger to any aircraft. Ice building up on wings and controlsurfaces basically changes the geometry of these parts of an airplane and thuschanges their aerodynamic characteristics. This means performance lossesand in worst case complete loss of lift generated by the wings. Ice or heavyprecipitation can also cause an engine flame out.

If flying in icing conditions actions have to be taken to minimize the risk of icing.

Icing conditions exist if:

• OAT / SAT is lower than 10° Celsius and/or visible moisture exists duringground operations

• TAT is lower than 10° Celsius and visible moisture exists in flight

OAT (Outside Air Temperature) or SAT (Still Air Temperature) means thetemperature of unmoved air. OAT and SAT is the same thing.

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TAT (Total Air Temperature) is the temperature measured by an aircraft movingthrough the air. TAT is always higher than OAT/SAT, as the air heats up when hittingthe moving aircraft.Visible moisture means clouds, fog, visibility of 1 mile or less, or snow rain.

De-icing

De-icing is a procedure by which snow, frost, ice and slush are removed from aircraftin order to provide clean surfaces. De-icing can be accomplished by use of fluids, bymechanical means or by heating the aircraft.

Anti -ic ing

Anti-icing is a precautionary procedure which provides protection against formation offrost or ice and accumulation of snow on treated surfaces of the aircraft.

Ai rcraft Ice Protect ion Systems

On a turboprop aircraft the ancillary power available (bleed air and electrical power)is less than on a jet. Consequently a permanent thermal protection is impracticable,in particular for the airframe. A solution consists in installing a pneumatic de-icing system on the exposed criticalparts (i.e. airframe) complemented by an electrical anti-icing protection for the partson which a pneumatic de-icing device is not practicable, i.e. on rotating components(such as propellers), windshields, probes. This philosophy is applied on all newgeneration turboprop airplanes.

Electrical heating

Permanent Level

• Probes and windshield Anti-icing

• Side windows (heating for defogging only)

• Flight control surfaces (ailerons, elevators, rudder)

• Inner leading edge of propeller blades (outer part is de-iced by centrifugalforce only)

Pneumatic de-icing system

• Wing and horizontal tailplane leading edges

• Engine air intakes and engine gas paths

Impact of contamination by ice or snow

As the aircraft’s external shapes are carefully optimized from an aerodynamic point ofview, it is no wonder that any deviation from the original lines due to ice accretionleads to an overall degradation of performance and handling, whatever the type. Thereal surprise comes from the amount of degradation actually involved and the lack of

a “logical” relationship with the type of accretion. The main effects of ice accretioncan be summarised as follows.

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The lift curves are substantially modified compared to clean aircraft;

• Lift is reduced at a given Angle of Attack

• Maximum Lift is reduced

• Maximum lift Angle of attack is reduced

Consequently an iced aircraft flying at a given speed will have a reduced stall margineither looking at AoA or looking at stall speed.

Drag is also heavily affected

• Greater drag at given angle of attack

• Greater drag at given lift

• Best lift/drag ratio at lower lift coefficient

The drag and lift penalties give a good idea of the performance impacts that could beexpected from ice accretion.Other effects should not be underestimated: for example, ice accretion on propellerblades will reduce the efficiency and the available thrust of propeller driven aircraft,ice accretion in the engine air intakes may cause engine flame out.

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4. Flight planning considerations

Choosing altitude and speed

The main rule for choosing an altitude or flightlevel is

As fast as possible as high as possible

For this there is a simple explanation: air molecules are one of the necessary valuesfor flight dynamics. Air molecules are producing the lift and you need lift for yourflight. As faster you’re going (relatively to the air, TAS=True Airspeed) the more lift isproduced. On the other hand these air molecules are producing drag. So we have tolook to reduce the amount of drag for our flight to reduce the fuel consumption and to

get a higher speed with less fuel using. Due the fact that the air molecules pervolume of air are reducing the higher you are pilots are looking to get as high aspossible for their flights. But please note that this achievement can’t be expanded tounlimited due the aircraft configurations.So ... based on the main rule a pilot has to look for his suitable cruising altitudes.

These altitudes are depending on several criteria:

• Weight of the aircraft in each stage of the flight• Aircraft configurations• Level Rules (ICAO, RVSM)

Flying a turboprop airliner your cruising altitude will generally be around FL220, onlyfor very short flights (shorter than 100nm) you will want to stay lower. Please refer tothe POH of your aircraft for actual values.You should be familiar with standard ICAO level rules, as RVSM airspace starts atFL290 and will not affect you in turboprop aircraft flying lower than that.

Standard ICAO Level Rules

Magneticcourse

Below18,000 feet MSL

At or above 18,000feet MSL but below

FL 290

At or aboveFL 290,

0°to 179° Odd thousands MSL,(3,000; 5,000; 7,000,

etc.)

Odd Flight Levels(FL 190; 210; 230,

etc.)

Beginning atFL 290;

(FL 290; 330;370, etc.)

180° to 359° Even thousands MSL,(2,000; 4,000; 6,000,

etc.)

Even Flight Levels(FL 180; 200; 220,

etc.)

Beginning atFL 310;

(FL 310; 350;390, etc.)

At cruise flight level always fly at the cruise speed published for your aircraft, which

will generally be slightly above 200 kts IAS. Again, please refer to the POH of your Aircraft.

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Appendix

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I, Acknowledgements

All the engine schematics in the first part of this manual were made by Mr. TomBenson and his team from NASA Glenn Research Center.

GRC runs a website, containing in-depth information about aircraft propulsionsystems. Have a look:http://www.grc.nasa.gov/WWW/K-12/airplane/shortp.html

Two books I’d like to recommend are “Be a better pilot” and “Make better landings”,both written by Alan Bramson. These books are actually made for private pilots,mainly focusing on flying planes of the size of a Cessna Skylane. But all theknowledge written down in these books has to be considered as “basics” foreveryone flying an airplane. They are not the cheapest, around 45€ each, but if youwant to read interesting and funny books about flying, get them.

Another good and actually quite extensive source for pilots is the “Learning Center”that comes with MSFS. In my opinion it is structured in a rather confusing way, but ifyou take some time you will find a lot of info.

A big “Thank You” goes to everyone who helped me to write this manual by reviewingit and checking for mistakes or who gave constructive criticism.

II, Links to resources

Flight planning

Online Route Finder http://rfinder.asalink.net/free/ Online Aviation Weather http://weather.noaa.gov/weather/coded.html NOTAMs, NATs, PACOTs https://www.notams.jcs.mil/ Terminal / Approach charts http://www.navdata.at/php/charts/charts.php

Aviat ion Knowledge

Covering physics of flight http://www.av8n.com/how/#mytoc Aircraft propulsion systems http://www.grc.nasa.gov/WWW/K-

12/airplane/shortp.html

Aerodynamics http://www.grc.nasa.gov/WWW/K-12/airplane/short.html

Regarding safety http://www.smartcockpit.com/

III, PIREP form

If you do not file your PIREPs online or just want to keep tack of your flights “onpaper”, feel free to use the following page printed to do so.

V1.1 PAGE 20


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Dep. Apt. Arr. Apt. Flight #

T out / off / T on / in / AC

Cruise alt./FL Fuel out Zulu t out

Cruise Mach Fuel in Zulu t in

Distance Fuel used Block t

Route

Comments

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++



Cruise alt./FL Fuel out Zulu t out

Cruise Mach Fuel in Zulu t inDistance Fuel used Block t

Route

Comments

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++



Cruise alt./FL Fuel out Zulu t outCruise Mach Fuel in Zulu t in


Route

Comments

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


T out / off / T on / in / ACCruise alt./FL Fuel out Zulu t out

Cruise Mach Fuel in Zulu t in


Route

Comments

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

turboprops tng manual.pdf

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