The majority of aeroplanes are not designed for ditching!

However, having said that, the statistical chances of surviving a ditching are high. It is estimated from UK and USA data that 88% of controlled ditchings result in few injuries to pilots or passengers.

You are more likely to die after ditching by drowning, usually hastened by hypothermia and exhaustion. By wearing a life jacket in the aeroplane your survival prospects are greatly improved. However in cold water, 15 degrees Celsius or less, your life expectancy in the water is only about one hour.

If one has to ditch what are the issues?

In general terms it is always preferable to impact the water as slowly as possible, under full control; don't stall the aeroplane in. Keep the wings parallel with the surface of the water on impact, i.e. wings level in calm conditions. One wing tip striking the water first will cause a violent uncontrollable slewing action.

In ideal conditions you should always ditch into wind because it provides the lowest speed over the water and therefore causes the lowest impact damage. This process is effective provided the surface of the water is flat or if the water is smooth with a very long swell inside which the aeroplane will come to rest.

If the swell is more severe, including breaking waves, it is more advisable to ditch along the swell, accepting the cross wind and higher speed over the water, because this is preferable to ditching into the face of a wave and nosing in. Ditching into the face of a wave is very likely to cause extreme damage to the aeroplane and violent deceleration with severe implications for passengers and crew. The final approach will result in considerable drift which you must control to achieve the required tracking over the water. You must be careful to maintain sufficient airspeed to ensure that any action you take in controlling the path of the aeroplane does not lead to a stall. You must retain complete control of the aeroplane.

In extremely windy conditions, greater than 20 knots for light aeroplanes with low stalling speeds or 30 knots or more for heavy aeroplanes with high stalling speeds, it may be worth ditching into wind to gain the large reduction in speed over the water. Aim to touchdown on the receding face of the swell. You may need to compromise between the beneficial effects of wind and the problems of swell. Advice on judging wind speed is provided at the end of this article.

In many cases, especially for modern or the more complex aeroplanes, the aircraft flight manual (or pilot's operating handbook) will provide detailed handling information for the execution of a ditching. In the absence of such information you should consider the following:

• Don life jacket if time permits;

• Reduce the aeroplane's weight to a minimum if you have time and if practicable. This will reduce the stalling speed and therefore your planned impact speed;

• Ensure landing gear is up and the associated circuit breaker pulled;

• Dispose of, or restrain, any loose articles in the cabin which could create a hazard during impact;

• Consider possible airframe distortion on impact and arrange to have an escape door or hatch open before impact so that you can vacate the aeroplane;

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