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Wind in P charts.

• Posts: 46

Dan created the topic: Wind in P charts.

Good Morning Bob, Stuart, and John,

Just after some clarification for the Perf exam. I understand that as per the CAO it is standard to use NIL wind (John gave a great example of why we use nil wind in a different thread) for landing charts when the question includes a TAF... I noticed in the text book that wind is a factor in the examples used, is this just for the sake of learning how to use the charts?.

My question is in the exam if wind is given not in a TAF, should i assume that i need to factor for it as per the text book?.

Cheers Dan.

• Posts: 1784

bobtait replied the topic: Wind in P charts.

The way I usually put it to a class is as follows.
If you are using a TAF to get the wind, then obviously you are not yet at the destination. In fact, if you are using the landing chart to establish the amount of weight you can carry into that strip then you haven't taken off yet. If the departure conditions and ZFW are not limiting, your take-off weight will be your maximum landing weight plus the weight of any fuel you burn on the way to the destination.

It would be fool-hardy to carry a weight that requires that a certain headwind component will be present at the moment you cross the fence to land. Surface wind is nearly always variable.

So, if you use a landing chart to establish a take-off weight, then use no wind. In fact you may notice that the CAO is talking about take-off when the statement about using no wind for landing is made.

However if an examiner simply says, "what is the maximum landing weight permitted under the following conditions" - and he gives you a wind, then use the wind.

• Posts: 46

Dan replied the topic: Wind in P charts.

Hi Bob,

That is a fantastic way to put it... certainly clears things up for me!.