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Old 26th Oct 2014, 06:15
  #17 (permalink)  
HarleyD
 
Join Date: May 2007
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FB has hit the nail on the head there.

If you are not familiar with the techniques for one way strips it's best to get some training/ guidance from an experienced pilot.

The issues associated with one way strips are numerous and nog always obvious to the uninitiated.

Tail wind on landing is often the main reason to prevent usage. There is no point launching in to a stiff headwind if you can't get back on.

Uphill tail winds create quite strong reverse wind shear and the wind is going uphill trying to lift the plane up with it.

Go around point may be well short of touchdown and once past this point you are committed like it or not, again the tail wind will significantly reduce climb in two ways by decreasing climb angle, GS/RoC, and the reversed wind shear will tend to decrease airspeed with increasing height during initial climb.

I have flown 2 and a half ton aircraft from 300m one way strips, so a savannah should be straight forward, but it is the unknown unknowns that can bring those new to one way hill strips undone, and I have seen it. In PNG I have flown into hill (mountains really) strips where the go around point was 500 metres from the strip which is still out of sight around a bend in the blind valley. These abort points are learned from the lessons of others, so you just use that advice and don't improvise. If you are arent on slope on speed at your go around point GO AROUND right away. Too high/ fast is just as bad as too slow/ low.

Go around is often to turn away down an escape route with descending terrain rather than a straight climb.

A sloping strip at the top of a steep bluff can also provide a vertical lift impulse right at flare which can increase speed and displace the aircraft significantly into the strip. Anticipating such a vertical by deliberately approaching low and slow is fine if it all goes as anticipated, otherwise you end up low and slow under profile and short of the strip on the wrong side of the drag curve. I have seen it.

Get a specialist with some type of industry experience, not a self taught 'expert' with limited knowledge of the traps. An aggie or ex aggie or an ex MAF or PNG pilot. They will identify hazards and assist you to put a little bag of tricks together to get you out of jail when conditions and micro climate make things difficult.

HD

My auto correct keeps trying to turn aggie into aggrieved. Maybe it's onto something.
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