6.2.4 Ignition Systems
The basic requirement of any ignition system is to deliver a high-tension spark to the spark plugs in each cylinder in the correct firing order at the correct time. This spark ignites the fuel/air mixture powering the pistons and producing work so to turn the propeller.
Magneto Ignition
A magneto uses a permanent magnet to generate an electrical current completely independent of the aircraft’s electrical system. The magneto generates sufficiently high voltage to jump a spark across the spark plug gap in each cylinder. The system begins to fire when the starter is engaged and the crankshaft begins to turn. It continues to operate whenever the crankshaft is rotating. The magneto system is mounted on the accessory drive unit located at the rear of the engine.

2502299114631500Most standard certificated aircraft incorporate a dual ignition system with two individual magnetos, separate sets of wires, and spark plugs to increase reliability of the ignition system. Each magneto operates independently to fire its own spark plug in each cylinder. The firing of two spark plugs in each cylinder improves combustion of the fuel-air mixture and results in a slightly higher power output. If one of the magnetos fails, the other is unaffected. This redundancy allows the engine to continue normal operation, although a slight decrease in engine RPM can be expected. The same concept of redundancy applies to the spark plugs. Operation of the magnetos are controlled in the flight deck through the ignition switch. The switch has five positions:
R (right)
L (left)

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With RIGHT or LEFT selected, only the associated magneto is activated. The system operates on both magnetos when BOTH is selected.
A malfunctioning ignition system can be identified during the pre-takeoff check by observing the decrease in R.P.M that occurs when the ignition switch is first moved from BOTH to RIGHT and then from BOTH to LEFT. A small decrease in engine R.P.M is normal during this check. The permissible decrease is listed in the POH. If the engine stops running when switched to one magneto or if the rpm drop exceeds the allowable limit, do not fly the aircraft until the problem is corrected.
The cause could be fouled plugs, broken or shorted wires between the magneto and the plugs, or improperly timed firing of the plugs. It should be noted that “no drop” in R.P.M is not normal, the aircraft should not be flown and sent in for immediate inspection.
“No drop” means one of the magnetos is not grounding and can result in unintended start-up by turning the propeller by hand. Following engine shutdown, turn the ignition switch to the OFF position. Even with the battery and master switches OFF, the engine can fire and turn over if the ignition switch is left ON and the propeller is moved because the magneto requires no outside source of electrical power. Be aware of the potential for serious injury in this situation.
Even with the ignition switch in the OFF position, if the ground wire between the magneto and the ignition switch becomes disconnected or broken, the engine could accidentally start if the propeller is moved with residual fuel in the cylinder. If this occurs, the only way to stop the engine is to move the mixture lever to the Idle Cut-Off (I.C.O) position, then have the system checked by a qualified AMO.
Starting Aids
In order to produce a spark in the plugs, the magneto spins a magnet within a soft iron coil core. This creates an alternating current within the coil and creates as much as 20 000 volts to fire the spark plugs. Effective sparks are only produced once the magnet is rotating at speeds of about 500 R.P.M. Any speed below this results in weaker sparks and prolongs engine start-up. Low engine R.P.M on start-up require a delayed spark in order to prevent kick-back. This is a premature power stroke caused by normal magneto timing set for higher R.P.M and can lead to the crankshaft being forced in the wrong direction.
Impulse coupling is incorporated into one of the magnetos to help overcome this problem on start-up. The benefits are two-fold. Firstly, it accelerates the rotation of the magnet producing a higher voltage, and therefore better spark, and secondly to retard the spark at lower R.P.M experienced during start-up.

The magneto employs spring weights and a spring-loaded coupling which initially prevents the magneto from turning. Once the spring is fully wound it releases the magnet which now, due to the increased rotational velocity, results in both a hot and late start during start. Once the engine is running, the centrifugal force of the flyweights ensures the impulse coupling is disconnected.

Ignition leads carry the high voltage generated by the magnetos to the spark plugs. The spark plug is designed in such a way as to allow this high voltage to jump between the central insulated electrode and the grounded electrode, creating a spark of sufficient intensity to ignite the fuel/air mixture under compression.
The spark plug is a useful indicator of engine condition. At each mandatory inspection the plugs are removed for inspection and testing. Normal engine operation is indicated by a light grey coating of the end of the plugs. Excessive wear may indicate detonation. In cases where the engine has been operated with too rich a mixture, black sooty-like deposits will appear. Whereas white powdery deposits will be found on plugs from engines operated with too lean a mixture. Black oily deposits indicate excessive oil consumption. If hard brittle deposits are found in the end cavity, lead in the fuel is not being removed during combustion, and if left, the deposits can build up sufficiently causing the high voltage to ground without a spark. This often results in a “mag drop” which can be identified by a rough running engine and an excessive loss in R.P.M. If this is detected on the ground during magneto checks, the flight must be abandoned. The gap between the central and ground electrode is adjustable and should be set to manufacturer requirements. Too small, or large a gap will affect the efficiency and size of the spark produced and can lead to incomplete combustion and a rough running engine.


6.6.1 Airworthiness

Contents TOC o “1-3” h z u Certificates To Be In Force PAGEREF _Toc526427745 h 3Certificate of Airworthiness PAGEREF _Toc526427746 h 5Certificate of Release to Service PAGEREF _Toc526427747 h 6Certificate of Registration PAGEREF _Toc526427748 h 8Radio Licence PAGEREF _Toc526427749 h 9Pilot’s Operating Handbook PAGEREF _Toc526427750 h 11Weight and Balance PAGEREF _Toc526427751 h 12Compliance with Requirements PAGEREF _Toc526427752 h 14Periodic Maintenance Inspections PAGEREF _Toc526427753 h 15Compliance with Flight Manual (or equivalent) Instructions PAGEREF _Toc526427754 h 17

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Certificates To Be In ForceWhen it comes to aviation, it’s not just a case of “kicking the tyres and lighting the fires”. Before every flight, a pre-flight check must be done. This entails not only checking that the aircraft is in an airworthy condition, but also that all of the correct documentation is present, and valid.

“When the weight of the paperwork is equal to the weight of the aircraft, you are ready to fly!” – Unknown
So, before you even begin the aircraft pre-flight, check the documents first; the last thing you want is to do an entire pre-flight only to find out right at the end that you don’t have the necessary paperwork!
Documents required
Sometimes the Law can be difficult to navigate and understand, so here is a simplified version…
Your Pilot Licence
Make sure it is valid
Make sure it is signed
Your Medical
Make sure it is valid
Make sure it is signed
Aircraft Documentation
Just remember “A R R R O W”
A – Certificate of Airworthiness
R – Certificate of Registration
R – Certificate of Release to Service
R – Radio Licence
O – Pilot Operating Handbook
W – Weight and Balance
Other documentation that is required:
Proof of Insurance
Aircraft Operating Certificate (Part 135/121)
Certificate of Approval (Part 141)
Aircraft Flight Folio
Valid Compass Deviation Card
Documents that are not permitted to be in the aircraft during a flight are:
Your logbook
The aircraft propeller logbook
The aircraft engine logbook
The aircraft airframe logbook
The reason for this is should those documents be destroyed or lost, then there might be no evidence of your experience, or of the aircraft maintenance records. There is, however, an exception to this rule; if an aircraft is to be exported its relevant logbooks may be in it, but copies must be made and stored in a safe location.

Period of Validity of Aircraft Documents:
Certificate of Airworthiness – 1 year
Certificate of Registration – 1 year (note, there is no expiry date, just a date of issue. Proof of payment of the annual fee accompanied by the original Certificate of Registration is required to ensure validity)
Certificate of Release to Service – 1 year OR at a total flight time
Release to Service is only valid if the Certificate of Airworthiness is valid
Radio Licence – 1 year
Pilot’s Operating Handbook – no expiry date, BUT, it must be kept up to date with the latest revisions and supplements
Weight and Balance – 5 years
Period of Validity of Other Documentation:
Proof of Insurance – 1 year
Aircraft Operating Certificate (Part 135/121) – 1 year
Certificate of Approval (Part 141) – 1 year
Valid Compass Deviation Card – 1 year from date of last compass swing

Certificate of AirworthinessThe Certificate of Airworthiness of a South African-registered aircraft is yellow piece of paper issued by the South African Civil Aviation Authority and states:
“This Certificate of Airworthiness is issued pursuant to the Convention on International Civil Aviation dated 7 December 1944 and Part 21 of the Civil Aviation Regulations, 2011, in respect of the above-mentioned aircraft which is considered to be airworthy when maintained and operated in accordance with the foregoing and the pertinent operating limitations.”
So in plain English, it means that the SACAA has deemed that the aircraft conforms to the SACAA’s rules and regulations, and is fit to fly, or Airworthy.

The Certificate of Airworthiness is valid for 1 year from the date of issue. It may not necessarily be the same date as the Certificate of Release to Service.

33610554470824The aircraft registration
00The aircraft registration
22098002008293005926664276937The expiry date of the certificate
00The expiry date of the certificate
1270000343069400left5343948The name of the certificate
00The name of the certificate

Certificate of Release to ServiceThe Certificate of Release to Service is issued by the AMO (Aviation Maintenance Organisation), and states that the aircraft and its equipment are serviceable for flight, and that the maintenance carried out has been in accordance with the Civil Aviation Regulations, and the aircraft’s Approved Maintenance Schedule.

The Certificate of Release to Service expires one year from the date of issue, or after a certain number of flight hours, whichever occurs first.

The number of flight hours might vary from type to type, as different aircraft have different maintenance schedules. In the case of light aircraft, a new Certificate of Release to Service is normally required every 100 hours. These hours might be based on Tachometer hours, or Hobbs hours, and will be stated on the certificate itself.

The inspection that is carried out to renew the Certificate of Release to Service is also called the “Annual Inspection”, or “MPI” (Mandatory Periodic Inspection).

If the Certificate of Airworthiness isn’t valid, the Certificate of Release to Service is also invalid.

487679109728000936624374904000548640899160005917233147646Make sure it is signed!
00Make sure it is signed!

3048004063365The name of the certificate
00The name of the certificate
3429002772410Date on which the certificate was issued
00Date on which the certificate was issued
31493881768898Flight time at which certificate expires
00Flight time at which certificate expires
22180551032510Check correct aircraft registration
00Check correct aircraft registration
13881102057188Date at which the certificate expires
00Date at which the certificate expires
45800431244177Check correct aircraft serial number
00Check correct aircraft serial number

Certificate of RegistrationEvery aircraft in South Africa is given a unique 5-letter registration.

These are randomly allocated, or specific registrations can be registered.

No two aircraft will have the same registration (can you imagine the confusion if two ZS-DVR’s were operating in the same airspace at the same time!)
In South Africa, aircraft registrations begin with “ZS/ZU/ZT”. Each country has their own specific designators, for example, Botswana is A2-, Namibia V5- and so on.
Within this, aircraft are broken down into type certified, non-type certified, helicopters, and RPAS (remotely piloted aircraft).

ZS-, is for type-certified fixed wings and helicopters.

ZU-, is for non-type certified fixed wings and helicopters (such as home-builts, or kit-planes).

ZT-, is for rotorcraft (both manned and remotely piloted).

left64579500The Certificate of Registration is valid for 1 year. There is no expiry date on the certificate itself, just a date of issue. Proof of payment of the annual fee accompanied by the original Certificate of Registration is required to ensure validity of the document.

-2209805393055The name of the certificate
00The name of the certificate
15392404996815Note no expiry date, only date of issue
00Note no expiry date, only date of issue
44208704394835Check correct aircraft serial number
00Check correct aircraft serial number
left4432935Check correct aircraft registration
00Check correct aircraft registration

Radio LicenceThe Radio Licence is issued by ICASA (The Independent Communications Authority of South Africa), which is an independent regulatory body of the South African government, established in 2000 by the ICASA Act to regulate both the telecommunications and broadcasting sectors in the public interest.

Every aircraft radio must be licenced. Even a handheld transceiver requires a licence, and you, as the operator of the radio, require a radio licence in order to legally be allowed to use it. (Receivers don’t require a licence).

As part of your training towards a Private Pilot Licence, you will be required to obtain a Restricted Radio Licence in order to be able to legally use the aircraft radio.

In order to keep the Radio Licence for the transceiver(s) valid, you need to pay an annual fee to ICASA. If you pay 5x the annual fee, then the licence will be valid for 5 years. Double check the paperwork after you have renewed it as there have been cases where 5 years were paid for, but it was only renewed for 1 year (and the money for the other 4 years vanishes mysteriously!)
Radio Licences are specific to the aircraft the radio(s) are installed in.

Should you wish to fit a different type of radio to your aircraft, you would need to obtain a new radio licence for that unit.

left748665The name of the certificate
00The name of the certificate
47015407620Details of installed equipment
00Details of installed equipment
3078480114300Date of expiry
00Date of expiry
15240009525Check correct aircraft registration
00Check correct aircraft registration

Pilot’s Operating HandbookAlso known as the POH, FIM (Flight Information Manual), PIM (Pilot Information Manual), or simply “Hand Book”. The POH contains all of the information needed to safely operate the aircraft from weights and limitations, to speeds, to normal procedures and emergencies, to the various systems.

We will look at the POH in more detail in later sections.

Weight and BalanceAlso called a Mass and Balance Report, in order to carry out accurate performance calculations, it is important to know the weight of the aircraft, and where its centre of gravity lies.

First let’s make sure we understand the various weights.

BEW – Basic Empty Weight
Basic weight of an aircraft including the crew, all fluids necessary for operation such as engine oil, engine coolant, water, unusable fuel and all operator items and equipment required for flight but excluding usable fuel and the payload.

ZFW – Zero Fuel Weight
The maximum permissible weight of an airplane with no disposable fuel or oil. In simple terms, zero fuel weight is the most an airplane can weigh when loaded with passengers and cargo with no usable fuel or oil on board.

MRW – Maximum Ramp Weight
The maximum weight authorised for manoeuvring (taxiing or towing) an aircraft on the ground as limited by aircraft strength and airworthiness requirements.

MTOW – Maximum Take-off Weight
The maximum weight at which the pilot is allowed to attempt to take off, due to structural or other limits
MLW – Maximum Landing Weight
The maximum aircraft gross weight due to design or operational limitations at which an aircraft is permitted to land
The AMO (Aircraft Maintenance Organisation) will weigh the aircraft in order to determine the BEW and centre of gravity so that the initial Certificate of Airworthiness can be obtained. The weighing process involves draining the fuel tanks so only unusable fuel remains. Quite the process!
Thereafter the aircraft must be re-weighed every 5 years, or if there are changes to the equipment or layout. For the most part the weight and balance reports will remain consistent over the years, but there are cases where an aircraft will mysteriously gain 100lbs, which not only affects the useful load (how much you can load into the aircraft), but it could also affect the centre of gravity.

If you use electronic flight planning software make sure the figures in the software match the figures on the Mass and Balance report! You will also find some aircraft brands use pounds and inches for measurement, while others might use kilograms and centimeters; double check the units and be careful of calculation errors!
The Mass and Balance report has a section for re-weighing due to equipment and/or configuration changes.

528002655168800035814044272200049834807719060Details of installed equipment
00Details of installed equipment
405384023164800027584408153400Date of reweigh and instructions on when to next weigh (every 5 years)
00Date of reweigh and instructions on when to next weigh (every 5 years)
14478007637145Check correct aircraft registration
00Check correct aircraft registration
1478279172974000990608406765The name of the certificate
00The name of the certificate
Compliance with RequirementsFailure to carry these documents on your flight, or to check that they are valid could result in a fine. It is always best to carry the original document. If, for whatever reason you can’t, then a certified copied must be used.

Failure to comply with any part of the Law could result in a fine, temporary grounding, or even permanent loss of license!
In 2011 the South African Civil Aviation Authority introduced a penalty system which comes in the form of monetary penalties for those who transgress the applicable civil aviation regulations.

More information can be found in Part 185 of the Regulations.

Periodic Maintenance InspectionsThere are 5 types of inspections:
Inspections as recommended by the manufacturer;
Mandatory periodic inspections;
Progressive inspections;
Block inspections; and
Other inspections.

Duplicate inspections
Non-scheduled maintenance inspections
Propeller strikes
For a full breakdown on each of the inspections, you can refer to Civil Aviation Technical Standards Part 43.

But to summarize, aircraft are required to undergo inspections at certain intervals. A minor inspection could be something like an oil change, whereas a major inspection could involve fitting a new engine or even removing the wings!
These inspections are required in order to maintain – or renew – the Certificate of Airworthiness, and are required to be carried out at a certain number of aircraft hours, or within a certain timeframe, whichever comes first.
Mandatory Periodic Inspections, or MPI’s, are required every 100 hours of flight time, or within a 12-month period.

The location and type of operation could also result in inspections being done more regularly. For example, aircraft operated by the sea might require more frequent corrosion checks or compressor washes. Inspections may never be less than the manufacturer’s recommendation.

Other inspections required could be the result of a hard landing, severe turbulence, limitation exceedences (VFE for example), lightning strikes, foreign-object damage, propeller strikes etc. In any of those cases, the manufacturer’s recommendations must be followed. If there is no specific procedure for a particular aircraft, the Director (of the SACAA) must be approached for guidance.

Most operators of piston aircraft will have a maintenance schedule where aircraft are inspected by the AMO every 50 flight-hours; this is a basic inspection that includes oil and filter changes, and sorting out any snags that might have been deferred. Depending on how busy the AMO is and the complexity of the aircraft, the 50 hour inspection shouldn’t take more than a couple of days.

The 100 hour inspection is more thorough and can take several days. Everything that would be done at a 50 hour inspection is done, and more. Some parts have a service life, and will be replaced or overhauled after a certain number of hours – this is called “TBO” Time Before Overhaul, and includes the engine, propeller, and starter motor among other things.

*Please note the above is with reference to type-certified aircraft. Non-type certified aircraft (NTCA), registered as ZU-, have a different system when it comes to maintenance. Rules and standards are less strict, but still well-monitored.

Compliance with Flight Manual (or equivalent) InstructionsThe Flight Manual, or Pilot’s Operating Handbook, is compiled by the aircraft manufacturer for that specific aircraft. It contains all the information required in order to safely fly that aircraft, from weight and structural limitations to maximum speeds and systems information.

The information and instructions contained in the flight manual must be adhered to. It has been created based on experience from test flights of that aircraft, and the information contained therein is for your safety. Flight manuals can be expensive to purchase, and cheaper generic checklists and manuals are available. But take caution! While the generic procedures might seem similar to those found in the Flight Manual, they are not designed for that specific aircraft and may miss important information!
If it says to approach at 70kts for landing, then that is the speed you follow. The flight manual might also contain information on particular characteristics of an aircraft, such as what happens when it stalls. It will also have warnings if a particular maneuver could lead to a dangerous situation – perhaps it likes to drop a wing and enter a spin at the stall, or it might like to go into a flat spin if you exceed a certain number of turns.

Along with knowing the procedures and checks for the aircraft you fly, it is also important to have a good understanding of the systems. Many a pilot has been caught out by something as simple a fuel selector in an aircraft with quirky fuel system, and inadvertently caused the engine to stop by switching the fuel off!
If you fly a lot of aircraft, there’s no harm in making a “cheat sheet” highlighting speeds and any unique procedures or quirks for that aircraft.

When in doubt, refer to the flight manual.

Example of a speed “cheat sheet”


6. Hvilken betydning har immigrationen for det amerikanske samfund?
Mexicanernes immigration til USA
Mexicanere er en af de største indvandrergrupper i USA, Næsten halvdelen af de mexicanske borger der er i USA er illegale indvandrere. En migrant forlader sit hjemland for at bo i et nyt land, Der kan være forskellige grunde til det f.eks. så det typisk pga. økonomiske vanskeligheder eller for at få forbedret deres muligheder end dem som de har i deres hjemland. De mexicanere som immigrerer sig til USA rejser for at finde arbejde og overleve. Mange af de der flyttede til USA er også såkaldte remitter som tjener penge og sender penge tilbage til familien i hjemlandet . Mexicanerne har været hårdt ramt af finanskrisen siden 2008 og det gjorde også at 80% af deres eksport og import er med USA . Mexico er også kendt for korruption og høj kriminalitet som også fører til at det meste af den narko der bliver solgt kommer fra Mexico, det er en af grundene til også at komme væk derfra og komme ind til USA .
Men efter som Donald Trump blev valgt som præsident så har han kun gjort mulighederne for mexicanske immigranter svære. Donald Trump har været ude og sige at han vil bygge en mur for at lukke grænserne mellem Mexico til USA, Donald Trump kræver 20% afgift på deres import så de selv kan betale for muren som han drømmer om, han vil så også firedoble tolden på de mexicanske vare for at de skulle kunne betale for hele væggen. Hvidvaskning af penge for at de skal arbejde i USA og sende tilbage til familien i Mexico vil han også prøve at stoppe for at kunne holde dem på en kort snor remitter skulle ikke kunne få sendt den sum penge som de sparer op og sender tilbage der vil han prøve at lægge og forhøje skatten på dem der vil give penge til familie i Mexico .


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