Prospective Sky Guides for Fixed Wing Aircraft

Airline transport operations are carried out in a wide range of visual and instrument meteorological conditions. For all but the most limiting of degraded visibility situations, the pilot can choose to fly the approach to the airfield and land the aircraft manually. S/he does this using the visual cues available through the cockpit windshield. The answer to the question - how is this achieved may seem rather obvious, but has actually challenged researchers for some time. The Prospective Sky Guides (Fixed Wing) project used the Ecological Approach to motion perception and its later development, Tau Theory, to try to answer this question and develop guidelines for the design of future pilot vision aids.

Principle Investigator: Prof. G.D. Padfield; Co-Investigator: Dr. K. Nuttall; Research Associate: Mr. M. Jump.  Funding body: Engineering and Phyiscal Sciences Research Council (EPSRC), standard research grant GR/R84795/01.

Limited visibility is ‘the single most critical factor affecting safety of worldwide aviation operation.  Thirty percent of all fatal accidents worldwide are a result of impacts into terrain or obstacles the pilot did not see’ (source: US Aviation Safety Programme).

Many natural species rely primarily on optical information to follow a safe path through the cluttered environment near the Earth’s surface.  In a similar way, pilots use visual perception to create a mental model of where their aircraft will be in the future to fly a safe path through their surroundings.  The reliability of this model is particularly critical when flying close to the ground or near to obstacles.  In a good visual environment, the pilot is usually able to pick up sufficient information from the available visual scene.  As the visual environment degrades, for example, due to adverse weather conditions, the available visual information becomes less reliable.  To counteract this degradation, the pilot requires some form of guidance vision aid.

To provide such a guidance vision aid, a complete reconstruction of the natural world from active/passive sensors coupled with terrain databases would be an arduous and expensive task in the medium term.  This begs the question: what is the minimum necessary and sufficient visual information required by a pilot to develop a reliable mental model, rather than a dangerous illusion, that will allow safe flight through the surrounding environment ?  Use the links below to find out how the research attempted to answer this question for the approach and landing phases of flight.