FEAST Visual Perception and Memory 2 — Questions and Answers
Question 1: On a radar display, a primary radar return (skin paint) appears without an associated secondary radar return (transponder). This most likely indicates:
- An aircraft with a non-functional or switched-off transponder (Correct answer)
- A helicopter that is too small to return a secondary signal
- A radar equipment malfunction affecting secondary returns only
- A bird strike that has disabled the transponder and damaged the aircraft
Correct answer: An aircraft with a non-functional or switched-off transponder
A primary return without secondary return typically indicates either a transponder failure, switched-off transponder, or an unequipped aircraft — requiring closer monitoring and potential coordination.
Primary radar detects objects by reflected radio energy — it does not require aircraft equipment. Secondary Surveillance Radar (SSR) requires the aircraft's transponder to receive and respond to interrogation signals. A primary-only return (no transponder response) means either the transponder is switched off, malfunctioning, or the aircraft is not equipped with one. Controllers must give particular attention to primary-only returns as they cannot be positively identified or interrogated for altitude. FEAST visual perception tasks include identifying and interpreting different radar display presentations.
Question 2: A controller looks at a radar scope and must compare the current positions of 6 aircraft with their positions from 30 seconds ago. The mental skill primarily required is:
- Visual working memory — holding the previous positions in memory and comparing with current positions (Correct answer)
- Spatial reasoning — calculating geometric relationships between tracks
- Processing speed — quickly scanning and updating all 6 positions
- Long-term memory — recalling previously memorised radar patterns
Correct answer: Visual working memory — holding the previous positions in memory and comparing with current positions
Comparing current and previous positions requires holding the earlier positions in visual working memory while simultaneously viewing current positions.
This task requires visual working memory (also called visuospatial sketchpad) — the component of working memory that temporarily holds visual and spatial information. The controller must maintain the 6 previous positions as mental representations while updating them against current radar returns to detect changes, trends, and potential conflicts. This differs from long-term memory (which stores learned information) and from real-time spatial reasoning (which processes current information without needing to remember prior states). FEAST visual memory subtests specifically target this comparison function.
Question 3: On a radar display, three aircraft are in a line between positions A and B. Aircraft 1 is at A, Aircraft 2 is at midpoint, Aircraft 3 is at B. Which is the most visually salient cue that aircraft 2 is at risk of being involved in a conflict?
- Aircraft 2 is between two other tracks — geometrically constrained with nowhere to manoeuvre without conflicting with one of the others (Correct answer)
- Aircraft 2 is at the midpoint, which is the centre of attention on any radar display
- Aircraft 1 and 3 are at the ends, which are lower risk positions
- Aircraft 2 must be in the most dangerous position because it was listed second
Correct answer: Aircraft 2 is between two other tracks — geometrically constrained with nowhere to manoeuvre without conflicting with one of the others
Being geometrically sandwiched between two other aircraft limits manoeuvre options and increases conflict risk — this is a visual-spatial reasoning element requiring 3D track awareness.
When an aircraft is between two others on a shared track, any manoeuvre to resolve a conflict with one will risk creating or worsening a conflict with the other. Controllers must visually identify geometrically constrained aircraft — those with limited safe manoeuvre space — as requiring particular care in conflict planning. This requires interpreting spatial relationships on the radar display, not just individual aircraft positions. FEAST visual perception tasks include multi-aircraft geometry interpretation to assess this skill.
Question 4: A radar display uses colour coding: green = normal, amber = alert, red = critical. A controller working in a dimly lit operations room suddenly sees a red track. The most likely visual processing pathway that allows fastest detection of this red track among green tracks is:
- Pre-attentive feature detection — colour is processed in parallel across the visual field without requiring focused attention (Correct answer)
- Serial visual search — systematically checking each track for the red colour
- Working memory recall — remembering which sectors typically show red tracks
- Peripheral vision detection — the controller is using their peripheral retina to detect colour change
Correct answer: Pre-attentive feature detection — colour is processed in parallel across the visual field without requiring focused attention
Colour is a pre-attentive visual feature — it pops out automatically in parallel visual processing, allowing immediate detection without serial search.
Pre-attentive visual processing handles basic features like colour, orientation, size, and motion in parallel across the entire visual field before conscious, focal attention is engaged. A uniquely coloured item (a red target among green items) 'pops out' immediately — detection time does not increase with the number of distractors. This is why ATC radar systems use colour coding — it leverages pre-attentive feature detection for fastest possible alert recognition. FEAST visual perception tests are partly designed around knowledge of which display features support fastest visual processing.
Question 5: A controller has been monitoring a radar display for 30 minutes. A new aircraft track appears that differs from the established traffic pattern. Despite the difference, the controller takes 15 seconds to notice the new track. This delay is most consistent with:
- Change blindness — the failure to notice changes in a complex visual scene when attention is not focused on the changing element (Correct answer)
- Slow processing speed due to fatigue after 30 minutes of monitoring
- The new track being too small to be visually detected on the display
- The controller's attention being drawn to a more critical established track
Correct answer: Change blindness — the failure to notice changes in a complex visual scene when attention is not focused on the changing element
Change blindness is a well-documented phenomenon where changes in a complex scene go undetected unless attention is specifically directed to the changing element.
Change blindness is the surprising failure to detect changes in a visual scene that occur outside the focus of attention. In complex radar displays with many tracks, a new track appearing in an unattended area can go unnoticed for seconds. This is not simply due to fatigue — it occurs even with fresh, rested observers. ATC systems use motion highlights and audio alerts to counteract change blindness by directing attention to new elements. FEAST visual perception tests include change detection tasks to measure candidates' susceptibility to change blindness in simulated radar displays.
Question 6: Pattern recognition in ATC visual perception means:
- The ability to rapidly match observed radar display configurations to familiar traffic patterns from training and experience (Correct answer)
- Recognising individual aircraft liveries on camera feeds at the airport
- Reading and interpreting alphanumeric labels on radar tracks
- Identifying weather patterns from meteorological display overlays
Correct answer: The ability to rapidly match observed radar display configurations to familiar traffic patterns from training and experience
ATC pattern recognition involves rapidly comparing current display configurations to stored templates of known traffic patterns, enabling faster situation assessment than item-by-item analysis.
Expert ATC pattern recognition operates at the level of traffic configurations — experienced controllers see familiar patterns (typical merge, crossing conflict, holding stack, approach sequence) and can rapidly assess them against known templates rather than analysing each aircraft individually. This chunked, template-based processing is faster and less working-memory-intensive than step-by-step analysis. FEAST assesses visual pattern recognition by presenting display configurations and testing how quickly and accurately candidates identify traffic scenarios — a predictor of how well they will develop expert-level situation assessment in training.
FEAST Visual Perception and Memory 2
On a radar display, a primary radar return (skin paint) appears without an associated secondary radar return (transponder).
This most likely indicates: