TRAFFIC COLLISION AVOIDANCE SYSTEM(TCAS).pptx

notes

1. AVIONICS 02/03 MODE III PHASE II AIRCRAFT EMERGENCY SYSTEMS BY woI(RTD) C N MAYABI INTRODUCTION

2. LESSON OBJECTIVE AT THE END THE OF THE LESSON,THE STUDENT SHOULD BE ABLE TO CORRECTLY EXPLAIN ;- THE PRINCIPLES OF OPERATION OF TRAFFIC COLLISION AVOIDANCE SYSTEM. DEFFERENT TYPES OF TRAFFIC COLLISION AVOIDANCE SYSTEMS.

3. LESSON SCOPE ANALYSIS OF TRAFFIC COLLISION AVOIDANCE SYSTEMS. -TCAS I -TCAS II

4. A modern approach ATC PPI

5. Controlling the skies

6. EMERGENCY INTRODUCTION. DEFINITION . The ever increasing volume of air traffic has caused a corresponding increase in concern over collision avoidance. Ground-based radar, traffic control, and visual vigilance are no longer adequate in today’s increasingly crowded skies. Onboard collision avoidance equipment, long a staple in larger aircraft, is now common in general aviation aircraft. New applications of electronic technology combined with lower costs make this possible.

7. ATCAS CONT------ Traffic collision avoidance systems (TCAS) are transponder based air-to-air traffic monitoring and alerting systems. The transponder of an aircraft with TCAS is able to interrogate the transponders of other aircraft nearby using SSR technology (Mode C and Mode S). This is done with a 1030 MHz signal. Interrogated aircraft transponders reply with an encoded 1090 MHz signal that allows the TCAS computer to display the position and altitude of each aircraft.

8. TYPES OF ATCAS There are two classes of TCAS. TCAS I TCAS II

9. TCAS I AND II Both systems provide warnings known as ‘advisories’ to alert the crew of the potential collision.TCAS I assists the crew in visually locating and identifying an intruder aircraft by issuing a traffic advisory (TA) warning.TCAS II is a collision avoidance system ,and in addition to traffic advisories,provides vertical flight manvouver guidance to the crew.This is a form of resolution advisory(RA) for thread traffic.A resolution advisory will either increase or maintain the existing vertical separation from the intruder aircraft.If the two aircrafts in close proximity are equipped with TCAS II,the flight manvourver is coordinated between both aircraft.

10. TCAS I TCAS I was developed to accommodate the general aviation community and regional airlines. This system identifies traffic in a 35–40 mile range of the aircraft and issues Traffic Advisories (TA) to assist pilots in visual acquisition of intruder aircraft. TCAS I is mandated on aircraft with 10 to 30 seats.

11. TCAS II TCAS II is a more sophisticated system. It is required internationally in aircraft with more than 30 seats or weighing more than 15,000 kg. TCAS II provides the information of TCAS I, but also analyzes the projected flightpath of approaching aircraft. If a collision or near miss is imminent, the TCAS II computer issues a Resolution Advisory (RA). This is an aural command to the pilot to take a specific evasive action (i.e., DESCEND). The computer is programmed such that the pilot in the encroaching aircraft receives an RA for evasive action in the opposite direction (if it is TCAS II equipped). [Figure 1]

12. TCAS CONT--------

13. TCAS SIGNAL PROCESSING Should the aircraft come within the horizontal or vertical distances shown in Figure 1, an audible TA is announced. The pilot must decide whether to take action and what action to take. TCAS II equipped aircraft use continuous reply information to analyze the speed and trajectory of target aircraft in close proximity. If a collision is calculated to be imminent, an RA is issued.

14. TCAS ACTION

15. TCAS CONT----------------- TCAS target aircraft are displayed on a screen on the flight deck. Different colors and shapes are used to depict approaching aircraft depending on the imminent threat level. Since RAs are currently limited to vertical evasive maneuvers, some stand-alone TCAS displays are electronic vertical speed indicators.

16. TCAS CONT- ----- Most aircraft use some version of an electronic horizontal situation indicator (HIS) on a navigational screen or page to display TCAS information. [Figure 11-132] A multifunction display may depict TCAS and weather radar information on the same screen. [Figure 11-133] A TCAS control panel [Figure 11-134] and computer are required to work with a compatible transponder and its antenna(s). Interface with EFIS or other previously installed or selected display(s) is also required. TCAS may be referred to as airborne collision avoidance system (ACAS), which is the international name for the same system .

17. TCAS BLOCK DIAGRAM

18. TCAS DISPLAY

19. TCAS MAJOR COMPONENTS The major system components are: Receiver –transmitter computer unit Two display units One or two mode s transponders System control panel Required antennas

20. TYPES OF ELTs Automatic ejectable or automatic deployable (A or AD) Fixed non ejectable or automatic fixed ( F or AF ) Automatic portable(AP) Personnel activated (P) Water activated or survival (W or S)

21. A or AD ELT This type of ELT automatically ejects fro the aircraft and is set in operation by the inertia sensors when the aircraft is subjected to a crash deceleration force acting through aircraft’s flighty axis. This type is expensive and is seldom used in general aviation.

22. F or AF ELT This type of ELT is fixed to the aircraft and is automatically set in operation by an inertia switch when the aircraft is subjected to crash deceleration forces acting in the aircraft’s flight axis. The transmitter can be manually activated or deactivated and some cases may be remotely controlled from the cockpit.This is the mostly used type on aircrafts.

23. AUTOMATIC PORTABLE(AP) This type of ELT is similar to type F or AF except that the antenna is integral to the unit for portable operation.

24. PERSONNEL OPERATED This type of ELT has no fixed mounting and does not transmit automatically. Instead ,a switch must manually operated in order to activate or deactivate the ELT’s transmitter.

25. WATER ACTIVATED OR SURVIVAL This type of ELT transmits automatically when immersed in water. It is waterproof , floats and operates on the surface of the water. It has no fixed mounting and should be tethered to survivors or rafts by means of supplied cord

26. ELT COMPONENTS ELT components include: a cockpit mounted panel the ELT a permanent mount antenna a portable antenna.

27. ELT MAINTENANCE ELTs must be inspected regularly with the manufacturers recommendations, atleast within 12 months of previous inspection for proper installation, battery corrosion, operation of the controls and crash sensor, and the presence of a sufficient signal at the antenna.

28. ELT TESTING Built-in test equipment facilitates testing without transmission of an emergency signal. The remainder of the inspection is visual. Technicians are cautioned to not activate the ELT and transmit an emergency distress signal. Inspection must be recorded in maintenance records including the new expiration date of the battery. This must also be recorded on the outside of the ELT.

29. ELT INSTALLATION ELTs are typically installed as far aft in the fuselage of an aircraft as is practicable just forward of the empennage. The built-in G-force sensor is aligned with the longitudinal axis of the aircraft. Helicopter ELTs may be located elsewhere on the airframe. They are equipped with multidirectional activation devices. Follow ELT and airframe manufacturer’s instructions for proper installation, inspection, and maintenance of all ELTs.

30. ELT LOCATION ON AIRCRAFT

31. ELT MOUNTING REQUIREMENTS The following requirements apply: When installed in a fixed wing aircraft,ELT should be mounted with its sensitive axis pointing in the direction of flight. When installed in rotorcraft ELT should be mounted with its sensitive axis pointing approximately 45 degreesdownwards from the normal forward direction of flight. ELT should be installed to withstand ultimate inertia forces of 10 g upward,22.5 g downwards,45 g forward and 7.5 g sideways.

32. ELT MOUNTING REQUIREMENTS------ The location chosen for the ELT should be sufficiently free from vibration to prevent involuntary activation of the transmitter. ELT should be located and be mounted so as to minimize the probability of damage to the transmitter and antenna by fire or crashing as a result of crash impact. Elt should be accessible for manual activation and deactivation.

33. TYPE W ELT BLOCK DIAGRAM

34. Surveillance…. INDEPENDENT SURVEILLANCE (NON-COOPERATIVE SYSTEMS) Independent surveillance (Non-cooperative systems.): Under this form of surveillance, systems on the ground (such as  Primary surveillance radar( PSR ) are able to locate the aircraft and measure its position from the ground by transmitting pulses of radio waves which reflect off the aircraft's hull. Current surveillance system is either based on radar (primary surveillance radar) or secondary surveillance radar ( ssr ) which measures range and azimuth of aircraft from the ground station.

35. PRIMARY SURVEILLANCE RADAR. PRIMARY SURVEILLANCE RADAR (PSR) Primary surveillance radar is a conventional radar sensor that illuminates a large portion space with an electromagnetic wave and receives back the reflected waves from targets within that space. The term radar thus refers to a system used to detect and localize potentially non cooperative targets. Primary radar operation is based on the principle of echo location. Electromagnetic pulses of high power emitted by the radar antenna are converted into narrow wave front which propagates at the speed of light (300,000,000 m/s ).This is reflected back by the aircraft and then picked up again by the rotating antenna on its own axis.

36. PRIMARY SURVEILLANCE RADAR.…. A primary radar detects all aircrafts without selection, regardless of whether or not they pocess a transponder. The operator hears the echoes from any reflection. Therefore it performs transmission /listening continuously which covers the space 360 .The primary radar functions therefore result in in detection and measurements of positions if there is presence of a target by the recognition of the useful signal. The ground based radar provides information on the bearing and distance of the aircraft.PSR does not require carriage of any equipment by the aircraft and is capable of detecting almost any moving target. With increasing usage of more advanced surveillance systems the use of PSR for international air traffic management will diminish.PSR will however use of PARS for civil application is rapidly decreasing.

37. SECONDARY SURVEILLANCE RADAR (SSR) The secondary surveillance radar ( ssr ) interrogates the transponder equipment installed in the aircraft. In mode “A” the aircraft transponder provides identification information, aircraft bearing and distance and in mode “C” it provides pressure, attitude information. The current ssr is in wide use in many parts of the world where terrestrial line of sight surveillance systems are appropriate. The accuracy resolution and overall performance of the range and azimuth information is significantly improved by the application of the monopulse (including large vertical aperture antennas) and other advanced processing technologies.

38. NEXT GEN -ADVANCED SURVEILLANCE SYSTEMS FOR AIRCRAFTS The FAA is implementing a broadcast services ground network that will deliver to the flight deck real-time access to weather, traffic and advisory aeronautical information. The broadcast service will utilize aeronautical digital communications, or data link, that provides high-speed exchange of information between aircraft and ground-based systems or between aircraft. Avionics displays will be used to present this information to the flight crew. The term “broadcast services” encompasses three forms of broadcast information: Automatic Dependent Surveillance – Broadcast (ADS-B) Traffic Information Services – Broadcast (TIS-B) Flight Information Services – Broadcast (FIS-B).

39. AUTOMATIC DEPENDENT SURVEILLANCE BROADCAST (ADS-B). ADS-B is a function on an aircraft or vehicle that periodically broadcasts its state vector (horizontal and vertical position, horizontal and vertical velocity) and other information. ADS-B is expected to play an increasing role in the NAS as its capabilities evolve, and is expected to be a key element in improving use of airspace, reducing ceiling and visibility restrictions, improving airport surface surveillance, and enhancing safety features like Airborne Conflict Management (ACM). The ADS-B architecture may utilize a combination of enabling data links to achieve the appropriate intended function. These links include the 1090 MHz Extended Squitter (ES) and the UAT). ADS –B is automatic because no external stimulus is required( eg interrogation) is required to elicit a transmission ,it relies on onboard aircraft position sources ( eg GPS) and on board link system to provide the surveillance information to other users.

40. How ADS-B Works Automatic dependent surveillance-broadcast is a GPS-based system meant to replace the traditional radar-based technology ATC has relied on for decades to detect and manage aircraft traffic. The GPS-based system determines highly accurate position and groundspeed information, and relays it to ATC and other ADS-B-equipped aircraft.

41. ADS-B ….

42. ADS-B…. ADS-B is a system in which electronic equipment onboard an aircraft automatically broadcasts the precise location of the aircraft via a digital data link. The data can be used by other aircraft and air traffic control to show the aircraft’s position and altitude on display screens without the need for radar. The system involves an aircraft with ADS-B determining its position using GPS. A suitable transmitter then broadcasts that position at rapid intervals, along with identity, altitude, velocity and other data. Dedicated ADS-B grounds stations receive the broadcasts and relay the information to air traffic control for precise tracking of the aircraft.

43. TRAFFIC INFORMATION SURVEILLANCE(TIS-B ) TIS-B is a traffic reporting system that uses ADS-B ground stations and radar data to transmit aircraft position data to aircraft cockpit displays. In essence, TIS-B will allow pilots in the cockpit to see what the air traffic controller sees - other aircraft, along with those aircraft's altitudes, direction, and speed vectors on their aircraft's

44. HOW TIS –B WORKS TIS-B data is transmitted from a ground station to all  ADS-B equipped  aircraft, whether the aircraft uses a 1090 MHz ES link or a 978 MHz UAT data link. The traffic information is taken from radar sensors on ground stations and broadcast through ADS-B data links to aircraft. The aircraft's ADS-B receiver will interpret the data and display it onto a screen in the cockpit. The actual interface on which TIS-B will be displayed will vary with the various different types of avionics on the market today, but it will most likely be incorporated into a flight management system or an electronic flight bag (EFB) to some standard degree. Typically, traffic is displayed as a small triangle with a line showing the aircraft's direction and speed, and the altitude readout somewhere next to the aircraft's triangle icon.

45. FLIGHT INFORMATION SYSTEM-BROADCAST (FIS-B) FIS-B is short for Flight Information System-Broadcast - a data broadcasting service that works along with  ADS-B  to allow aircraft operators to receive aeronautical information such as weather and airspace restrictions through a data link to the cockpit. Along with its partner system  TIS-B , FIS-B is available at no cost to ADS-B users as part of the FAA's Next Generation Air Transportation System ( NextGen ). The system gathers information through the use of ADS-B ground stations and radar and delivers that data to an aircraft's onboard cockpit display in the form of weather alerts, airport information and various other reports. FIS-B was created for use by general aviation pilots.

46. HOW FIS –B WORKS Information for FIS-B is transmitted from ground stations to participating ADS-B In aircraft on a 978 MHz UAT data link. Aircraft that use a 1090 MHx   Extended Squitter transponder will not be eligible to receive the FIS-B product. There are currently over 500 operation ground stations that are part of the ADS-B network, and the FAA is working to add approximately 200 additional stations. The aircraft's ADS-B receiver (known as ADS-B In) interprets the data and displays it onto a screen in the cockpit. The actual interface on which FIS-B will be displayed will vary, but it will typically be incorporated into a flight management system or an electronic flight bag (EFB).

47. FIS- B…… FIS-B is strictly an advisory service and is not meant to take the place of standard weather briefings and preflight planning. It is not a substitute for official weather sources such as air traffic control, flight service stations, NOAA or DUATS. FIS-B data link services operate in line-of-sight only. Aircraft receivers must be within the service volume of the ground station to receive FIS-B.

48. Q&A OK, what did I not make perfectly clear ?

49. LESSON OBJECTIVE AT THE END THE OF THE LESSON,THE STUDENT SHOULD BE ABLE TO CORRECTLY;- EXPLAIN WHAT IS ADS-B WHAT IS FIS-B. WHAT IS TIS-B

50. REFERENCE STUDENTS NOTES

51. TAKE HOME

52. Q1.Define what is ADS-B. Q2.Define what is TIS-B. Q3. Q6.Define what is FIS-B ?

53. LINK