ENGINE STARTING Starting an aircraft engine is a specialized procedure and varies with an individual engine and aircraft. Therefore, before starting any aircraft engine, be sure to study the procedures in the appropriate airplane flight manual and get instruction from an experienced operator. However, certain general guidelines apply to all reciprocating and turbine engine powered aircraft. Before starting an engine, besure to check all of the aircraft documents such as aircraft logbook Aircraft logbook contains all the information of the aircraft history and previous troubleshooting and problems that occurred during the flight operation. As an aviation technician, you must make sure that the aircraft is working properly under the airworthiness condition. In some general aviation, the other aircraft documents like the ARROW are attach along with the the aircraft logbook so that they can easily carry and check the aircraft. ARROW means: ● Airworthiness Certificate ● Registration Certificate ● Radio Certificate ● Operating manual or Pilot operating handbook (POH) ● Weight and balance certificate and nowadays, general aviation company added a Insurance Certificate. ENGINE STARTING PROCEDURES Reciprocating Engines In addition, prior to starting an engine, insure that the propeller area is clear to prevent possible injury and the technician should shout that the propeller area is clear. The aircraft should not be parked in an area of loose gravel, since small stones can be sucked up into the propeller and damage the blades Furthermore, be sure that the blast from the propeller does not blow dirt into any hangar or build ing or onto another aircraft. ENGINE STARTING PROCEDURES There is always a possibility of fire when starting an engine. Because of this, you should always have a carbon dioxide fire extinguisher of adequate capacity available. For starting large aircraft where it is not possible to see the engine when it is being started, a fire guard must be stationed near the engine. Induction system fires are the type which occur most frequently in reciprocating engines. The reason for this is if an engine is over-primed and then fires back through the carburetor, the gasoline in the induction system can ignite. If this occurs, the best procedure is to continue cranking and start the engine if possible. Once started, the engine will suck the fire into the cylinders, and no further damage can occur ENGINE STARTING PROCEDURES C172 Starting Procedure ● ● ● Before starting engine. Be sure to complete the pre-fight inspection, check and adjust the seats, seat belts, and shoulder harness. Turn the fuel selector valve on BOTH position and radio and electrical equipment to OFF. lastly circuit breakers must all CHECK IN position and brakes must test and set. C172 Starting Procedure ● ● ● ● ● During engine starting, Mixture control on RICH position, Carburetor heat on COLD or OFF position and Master Switch must be ON. Primer as required and in warm temperatures, apply 1 or 2 strokes of the primer should be sufficient. In colder temperatures, apply up to 6 strokes of the primer may be necessary. If the engine is warm, no priming is required and in extreme temperatures, it may be necessary to continue priming while cranking the engine. Open the throttle approximately ⅛ inch to provide air to enter into the induction system during starting. ● ● ● ● ● C172 Starting Procedure Propeller area must clear and all technician must response and acknowledge with a word CLEAR Start the starter with the starting switch or key (release when engine starts) If the engine is under primed (most likely in cold temperature with a cold engine) it will not fire at all, and additional priming will be necessary. As soon as the engine cylinder begin to fire, open the throttle slightly to keep the engine running. Oil pressure must check. After starting, if the oil gauge does not begin to show pressure within 30 seconds in the summertime and about twice that long in very cold weather, stop the engine and investigate. Lack of oil pressure can cause serious engine damage. After starting, make sure to avoid the use of carburetor heat unless icing conditions prevail. C172 Starting Procedure A weak intermittent firing followed by puffs of black smoke from the exhaust stack indicate overpriming or flooding. Excess fuel can be cleared from the combustion chamber by the following procedure: 1. Set the mixture control full lean and throttle full open 2. Then crank the engine through several revolutions with starter. 3. Repeat the starting procedure without any additional priming ENGINE STARTING PROCEDURES(video) ENGINE STARTING PROCEDURES HAND PROPPING Hand propping of aircraft engines is a procedure with which all technicians should be familiar, as it is possible for a battery to become discharged when no auxiliary power is available. It is important that no person ever attempt to prop an aircraft until being thoroughly checked out in the procedure. HAND PROPPING TURBINE ENGINE AIRCRAFT Turbine engine aircraft usually have enough automatic sequencing by the fuel controls so that starting is less involved than starting a reciprocating engine of comparable power. But the extremely high cost of turbine aircraft, and the possibility of severe damage in the event of an improper start, make it doubly important that only qualified personnel start these engines. One of the problems that can occur when starting a turbine engine is the lack of sufficient electrical power to get the engine up to proper speed for it to become self-accelerating in its operation. This condition can be minimized through the use of a ground power unit (GPU). Improper starts are usually one of two types, hot starts and hung starts, TURBINE ENGINE AIRCRAFT HUNG START- In gas turbine engines, a condition of normal light off but with rpm remaining at some low value rather than increasing to the normal idle rpm. This is often the result of insufficient power to the engine from the starter. In the event of a hung start, the engine should be shut down. HOT START - In gas turbine engines, a start which occurs with normal engine rotation, but exhaust temperature exceeds prescribed limits. This is usually caused by an excessively rich mixture in the combustor. The fuel to the engine must be terminated immediately to prevent engine damage. AIRCRAFT MARSHALLI NG Aircraft marshalling refers to the visual communication between ground personnel and pilots in order to lead an aircraft to the correct parking position at an airport or aerodrome. Marshalling is important because many pilots have limited vision both of the aircraft and of ground obstacles from the cockpit. AIRCRAFT MARSHALLING AIRCRAFT MARSHALLING FIXED WING AIRCRAFT MARSHALLING ROTRAY WING LIGHT SIGNALS Light Gun The light gun is a relatively large (but still handheld) projector which is aimed at the aircraft. The controller uses a trigger to transmit either a series of pulses or a continuous stream of light and may choose the colour of the beam (red, green or white). LIGHT SIGNALS LIGHT SIGNALS
