Avionics in general means all electronic,electric and instrumental equipment that are placed into the airplane or helicopter.Thus it consists from many branches.The first one will be the instruments. Instruments at the airplane or the helicopter are used for measuring and controlling various parameters during the ignition of the engine and during the flight.We can divide them into following groups.
Flight speed indicator,Altitude indicator,Variometer.All of them are powered by air pressure static or dynamic component or both of them.
Instruments for controlling the parameters of the engine
Engine RPM indicator,Main rotor RPM indicator,various temperature controllers for working temperature of components. Exhaust temperature controller everything is combined with such a fine automatics and is very reliable indeed.Shaft controllers, torquemeter they are all obliged to give a correct data to the flying crew.
Flight compass,Gyrocompass,Gyro horizon or artificial horizon plus rate of turn indicator and many others for secure navigation during the flight.
Electric equipment for airplanes
This area consists from two main parts
The main DC source is starter- generator or just generator if engine uses air pressure for starting.Auxiliary source is battery. Through various converters it converts DC into AC if there is a malfunction in main network.Mainly voltage is 28 v but at light and ultra light airplanes it is 14 V.There is also a large network of commutative equipment with voltage regulators and differential minimal relays included and many more regulators like exhaust temperature regulator during the starting phase of the engine.Various types of relays from 0,1 to 2000 amps.
Alternator is the main source of AC, voltage is mostly 208 V 400 Hz,115 v 400 Hz, through various transformers it can be 26 V 400 Hz or 36 V 400 Hz at russian types.Supplying many instruments for navigation, engine monitoring etc.Radio equipment also uses AC for work too.Secondary source is battery through the network of static converters and transformers .
Radio and Radar Equipment
This term include all devices for radio comm and all types of radars like weather or combat types.Also to navigate airplane to the start and middle point of runway for landing through the network of VOR-s.
Initial remark is vibrating temperature oscillation seen at exhaust temperature indicator at range from 50 to 300 C during the flight.For everyone who knows this type of engine it should be steady at 450 C.The engine RPM are fixed at 43500 which is excellent.The following procedure is check the RPM indicator.Done, it is accurate.Next is to check the resistance of the wires at thermocouple system.Found to be 18,03 Ohms.Fixed at variable resistor and adjusted it at strictly 16.02 ohms.The serial numbers of thermocouple senders indicated that value.
When I have approached the connector and disassemble it I have found that the pins are loose and their connection to the wires are bad.
So after carefully inspection there is a one pin with signs of overheating others are too but this one is more than others.Procedure follows.
Changing all four pins by new ones, Coat it carefully with thermo coater insulation , fixing the wires with clamps.Everything is now sure to be proven good and secur…