avionics system
Topic 1: Introduction to Avionics
Flying Blind or Zero-Visibility Flying
3 requirements:
1. Flying along the earth horizon
Artificial horizon – indicates attitude of aircraft with respect to the true horizon.
Without reference to the horizon, pilot, in zero visibility, could not know whether the forces on aircraft are due to gravity or an accelerated turn.
2. Safe altitude
Altimeter – measures altitude of aircraft. It enables pilot to avoid unseen mountains and other obstructions.
a) Barometric pressure altimeter – used for all aircrafts
b) Radio/radar altimeter – accuracy of 100ft. used for flight in low visibility.
3. Radio navigation aids to fly and land
Flight navigation system (VOR) – navigates and guides pilot to fly through the use of ground transmitter and aircraft receivers.
Flight landing system (ILS) – aids pilot to land aircraft without ever seeing the runway
Avionics Environment
Avionic systems are different from the ground based equipment carrying out similar functions. Reasons for these differences are:
• Achieving minimum weight to increase speed, range and effectiveness
• Very high reliability, safety and integrity
• Adverse operating environment
• Space constraints
Basic Definitions and Terminology
International Standard Atmosphere (ISA):
Mean sea level temperature: 15oC
Mean sea level pressure: 1013.25mb / 29.92InHg
Mean sea level pressure: 1.225Kg/m3
Pressure, temperature and density will decrease with increase in height.
Altitude (QNH) – vertical distance above mean sea level
Height (QFE) – vertical distance above a specified datum with known elevation
Flight level – 1013 datum (Sea level)
Measurements:
1 Nautical Mile (nm) = 6080 ft. or ~1.852 km
1 Knot = 1 nm/hr
1 degree = 60 min =60nm
Types of Avionic Systems
1. Navigation systems (Cockpit flight instrument, VOR, ILS)
Help pilot to navigate from one location to another location safely and regularly.
2. Communication systems (CVR, DFCR)
Use radio
Flying Blind or Zero-Visibility Flying
3 requirements:
1. Flying along the earth horizon
Artificial horizon – indicates attitude of aircraft with respect to the true horizon.
Without reference to the horizon, pilot, in zero visibility, could not know whether the forces on aircraft are due to gravity or an accelerated turn.
2. Safe altitude
Altimeter – measures altitude of aircraft. It enables pilot to avoid unseen mountains and other obstructions.
a) Barometric pressure altimeter – used for all aircrafts
b) Radio/radar altimeter – accuracy of 100ft. used for flight in low visibility.
3. Radio navigation aids to fly and land
Flight navigation system (VOR) – navigates and guides pilot to fly through the use of ground transmitter and aircraft receivers.
Flight landing system (ILS) – aids pilot to land aircraft without ever seeing the runway
Avionics Environment
Avionic systems are different from the ground based equipment carrying out similar functions. Reasons for these differences are:
• Achieving minimum weight to increase speed, range and effectiveness
• Very high reliability, safety and integrity
• Adverse operating environment
• Space constraints
Basic Definitions and Terminology
International Standard Atmosphere (ISA):
Mean sea level temperature: 15oC
Mean sea level pressure: 1013.25mb / 29.92InHg
Mean sea level pressure: 1.225Kg/m3
Pressure, temperature and density will decrease with increase in height.
Altitude (QNH) – vertical distance above mean sea level
Height (QFE) – vertical distance above a specified datum with known elevation
Flight level – 1013 datum (Sea level)
Measurements:
1 Nautical Mile (nm) = 6080 ft. or ~1.852 km
1 Knot = 1 nm/hr
1 degree = 60 min =60nm
Types of Avionic Systems
1. Navigation systems (Cockpit flight instrument, VOR, ILS)
Help pilot to navigate from one location to another location safely and regularly.
2. Communication systems (CVR, DFCR)
Use radio