VISUAL FLIGHT AT NIGHT ACCIDENTS: WHAT YOU CAN'T SEE CAN STILL HURT YOU ...

Acknowledgements: Australian Transport Safety Bureau

At night, less can be seen outside the cockpit to help you control your aircraft. Although flight instruments are used under both Night Visual Flight Rules (VFR) and Instrument Flight Rules (IFR), at some stage during a night flight you will also need to fly the aircraft with reference to what can be seen outside.

What can be seen outside an aircraft at night varies greatly between the almost day-like conditions of flying over a city under a full moon to the complete darkness of remote areas without any moon or significant ground lighting. Safe flight relies on pilots applying the correct flying skills using the combination of information from flight instruments and from outside the aircraft.

Many pilots fly mostly in daylight. Night flying, even when undertaken by appropriately qualified pilots, presents an added level of complexity. In most cases, pilots who operate at night have the necessary knowledge and skills and are flying suitably equipped aircraft.

A pilot who is qualified to fly visually at night should have the extra skills and equipment to control the aircraft by using flight instruments and by using more detailed flight procedures. Safe night visual flight requires the application, use and integration of all the information sources correctly. Compared with day visual flight, there is more to night visual flight than meets the eye.

Key message

The extra risks inherent in visual flight at night are from reduced visual cues, and the increased likelihood of perceptual illusions and consequent risk of spatial disorientation. These dangers can, however, be managed effectively. This report explains how suitable strategies can significantly reduce the risks of flying visually at night.

·     Night flying is more difficult than flying in the day. Ensure you are both current and proficientwith disciplined instrument flight. Know your own personal limitations in terms of flying with minimal or no visual references. Only fly in environments that do not exceed your capabilities.

·     Before committing to departing on a visual flight at night or close to last light, ensure your aircraft is appropriately equipped and consider all obtainable operational information, including the availability of celestial and terrestrial lighting.

·     Some nights and some terrain are darker than others. Excellent visibility conditions can still result in no visible horizon or contrast between sky and ground. Inadvertently flying into instrument meteorological conditions (IMC) is also harder to avoid at night.

·     Always know where the aircraft is in relation to terrain, and how highyou need to fly to avoid unseen terrain and obstacles.

·     Remain aware of illusions that can lead to spatial disorientation - they can affect anyone. Know how to avoid and recover from illusions by relying on instrument flight.

FLY SAFE!