Federal Aviation Administration Advisory Circular

h.CDTI.

1. 
   Displays. The ADS-B In system includes at least one flight deck traffic display (i.e., CDTI) depicting the relative position and related information of ADS-B equipped aircraft in a plan view (bird's eye view). The CDTI display may be presented on a dedicated display or integrated into and presented on an existing display (e.g., electronic flight information system (EFIS), multi-function display (MFD)). CDTI equipment should be compliant with the Class A or Class B requirements of TSOC195b. Class A equipment supports only the Basic Surface application. CDTI equipment should be installed in accordance with manufacturer instructions. Installation in a forward position requiring minimum head and eye movement (14 CFR 23.1321, 25.1321, 27.l321, and 29.1321) will provide the best situation awareness and support subsequent upgrades to other ADS-B applications. Side-mounted displays are acceptable for the basic situation awareness applications and ITP, but have limited potential to support more advanced applications. The display must be installed such that the pilots have an unobstructed view of the display when seated in their normal position. For general installation guidance on displays, refer to AC 2511B, Electronic Flight Displays and AC 23.1311-1C, Installation of Electronic Display in Part 23 Airplanes.
   

2. 
   ITP Installations. ITP installations must include a traffic display mounted in the forward position or as a side mounted display. The traffic display (plan view) must be visible during the ITP vertical maneuver. It is recommended but not required that a graphical vertical/profile view of the traffic be available for flight crews to aid in assessing initiation criteria. This is particularly helpful in situations where there is a significant angle between the track of the own aircraft and the ITP Traffic aircraft (the angle can be any value less than 45 degrees and still be a valid ITP situation). In these cases, relative geometry (ahead of or behind) may not be intuitive.
   

3. 
   Traffic Symbols. The FAA worked closely with industry to standardize the ADS-B In symbols and features. The resulting symbols are provided in Appendix B. The traffic display should depict the symbols, features, and information defined in the appendix. However, manufacturers may propose alternate symbols in order to integrate ADS-B with existing flight deck symbology. These alternate symbols will need to be justified by human factors analysis as part of the certification process. Alternate symbol sets are not allowed without additional justification. There is one exception to this guidance. It is acceptable to pair a TSO-C195b Class C ASSAP unit with an existing certified traffic display using legacy symbols (e.g., TCAS, TAS) when either the AIRB or EVAcq application are installed. Minor TSO changes or enhancements may be made to the previously approved traffic display without requiring the equipment to be made fully compliant to TSO-C195b requirements. This exception only applies to previously approved traffic displays. If any other applications beyond EVAcq or AIRB are installed, the display must be fully compliant with TSO-C195b.
   
   
   
   1. 
      Traffic Symbol and Ownship Symbol Reference Point. The airplane or rotorcraft flight manual or pilot’s guide for the ADS-B equipment must specify the location of the horizontal position reference point on the traffic symbols and the ownship symbol. For example, this position may be the center of the symbol or the tip of the traffic directional arrow. The ownship horizontal position reference point should be consistent with the existing flight deck philosophy. The traffic and ownship symbols are an abstract representation and are not required to reflect the physical extent of the aircraft. This becomes more evident when implementing the surface application with the underlying airport map.
      
      
      
4. 
   CAVS Installations. For installations that include the CAVS application, Traffic Identification, Ownship Ground Speed, Traffic Ground Speed, Differential Ground Speed (when aircraft are in-trail) and Digital Traffic Range must be displayed in the primary field of view to facilitate pilot monitoring. Refer to AC 25-11B. CAVS installations must include a means to designate traffic for CAVS.
   

5. 
   Required Controls. The CDTI control panel may be a dedicated control panel or it may be incorporated into another control, such as a multifunction control display unit (MCDU) or Flight Management Computer (FMC) control display unit (CDU). CDTI controls must be readily accessible from the normal seated position. Pilot controls for the ADSB In equipment must be provided as follows:
   

1. 
   A means to adjust the display range between the minimum and maximum values.
   
   
   
2. 
   A means to adjust the altitude band between the minimum and maximum values.
   
   
   
3. 
   A means to adjust the brightness of the display.
   
   
   
1. 
   Optional Controls. The following optional controls may be provided:
   

1. 
   A means to select between display of relative and actual altitude.
   
   
   
2. 
   A means to select at least one traffic element.
   
   
   
3. 
   A means to select alternate display criteria (e.g., filters and vertical views).
   
   
   
4. 
   A means to declutter, which removes optional traffic information when display of the information is not desired. If decluttering is implemented,
   
   
   
   1. 
      A means must be provided for the flight crew to control the decluttering.
      
      
      
   2. 
      The flight crew must be able to perform the declutter operation by a simple action.
      
      
      
   3. 
      The flight crew should be able to return to the previous state by a simple action.
      

4. 
   If automatic decluttering is implemented, a means should be provided for the flight crew to control the automated decluttering function.
   

1. 
   An indication that decluttering is active must be provided.
   
   
   
1. 
   A means to pan the view. If panning is implemented:
   
   
   
   1. 
      There must be a means to control panning.
      
      
      
   2. 
      There must be a means to return to the original view with a simple action.
      
      
      
2. 
   A means to designate traffic for an application (e.g. CAVS).