Saturday, 23 July 2016

TAKE-OFF: THE RISKIEST THREE MINUTES



 Acknowledgements: AIR FACTS/Dick Collins

“When I read of take-off accidents I think about how unforgiving airplanes can be if you fly away without the old ducks all in a row.

Take-offs seem easy, but they can quickly go wrong, as I found out. My airplane, on the ramp. Another pilot (my son) was flying. He started the engine, got clearance, but even though the airplane was parked on a downslope it didn’t start rolling with the application of a little power. There was really nothing to do but tell ground control we’d be a minute, do a complete shutdown, get out and pull the chocks, and then start all over again!

Whilst leaving a chock under the nose-wheel is not a life-threatening event, it can portend bad things. It comes from the same place that a neglected control lock, or inadequate sump draining, or not double-checking the fuel, or not properly latching doors comes from. And those things can all hurt.

Take-offs are wonderful manoeuvers, and I never fail to think it pure magic when the weight of the airplane shifts from the ground to the wings. It’s still the same airplane but when it flies it comes alive. That’s the happy part of taking off. But what comes next is a period of flight with few options and where any problem can quickly become serious.

One source indicates that ten percent of fatal accidents happen on take-off. Because the period of time is relatively short, this suggests that the risk is quite high. But many of the things that lead to trouble in the first three minutes of flight can be anticipated, so it is important not to rush through the pre-flight work. It is also likely that most accidents occurring in the first ten or fifteen minutes can be traced back to something neglected before departure.

I’ll give you another example. I was preparing for a low-visibility take-off one foggy morning. That meant moving deliberately through the pre-flight, checking everything at least twice. Such a take-off is demanding but I never thought it particularly risky. Something being askew would change that, thus all the double-checking. The need for careful preparation might not be quite as important on a clear day but it can still be pretty important. From that day forward I treated all pre-flight preparations equally, regardless of the weather.

Accidents occurring on or soon after take-off generally fall into two separate categories:

·  On an IFR departure, it usually relates to the pilot losing control of the airplane in roll
·  On a VFR departure, it usually relates to power - not enough, or not running well, or at all. A loss of control often follows, where the flaw is in pitch control. The pilot stalls the airplane after having a problem with the available performance.

There are proportionately a lot of IFR departure accidents. When departing in IMC I have always been a proponent of climbing straight ahead at full power in the take-off configuration until 1,000 feet above the ground. The transition from visual to instrument flying must be made when the airplane is rotated to a flying attitude. Doing it that way means that you can give your absolute attention to the attitude of the airplane. Staying visual for as long as you can see is not the way to do it.

So how do we approach this problem? Before take-off the pilot has to acknowledge that the next three minutes will be totally critical and that the mind-set can and will be on nothing but controlling the airplane.

All take-offs have a lot in common and even though instrument and visual departures have different requirements they share one strong similarity: if you don’t have all those ducks in a neat row before advancing the power, those first three minutes could be long and potentially painful”.

FLY SAFE!

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