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Declared Density Charts?

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Airflow_X created the topic: Declared Density Charts?

I understand with the recent changes that have come in that declared density charts are no longer included. I was curious what is being used now for operations at ALAs with no elevation data available regarding takeoff performance?
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bobtait replied the topic: Declared Density Charts?

Check out the Advisory Circular AC 91-02 v 1.1, paragraph 8.3.3. The P charts allow for temperature and elevation. So it looks like you work it out for yourself.
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  • John.Heddles
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John.Heddles replied the topic: Declared Density Charts?

One needs to keep in mind that the declared charts date back to developmental air services which are now rather dated in concept. They were never terribly good from an engineering point of view, not necessary for takeoff (although useful for planning from a different departure paddock) and of some value for landing calculations.

Better consigned to the filing cabinets of history in this engineer's view.

Engineering specialist in aircraft performance and weight control.
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John.Heddles replied the topic: Declared Density Charts?

I was curious what is being used now for operations at ALAs with no elevation data available regarding takeoff performance?

.. and some more information which might be of use. You can get access to a raft of map data via this site

www.ga.gov.au/scientific-topics/national...ata/topographic-maps

including the whole of Australia at 1:250000, which gives you heights to around 25 metres which is fine for light aircraft work. Takes a few minutes to download and search for your desired location but it works fine.

(If your location has a 1:50000 topo available, you are down to 5 metres or so. If you really are a glutton for punishment, you can look to the state sites and pay real dollars to get access to larger scales again but these, really, are of not much use for map reading on the fly, as it were).

Engineering specialist in aircraft performance and weight control.
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bobtait replied the topic: Declared Density Charts?

I guess it's reasonable to assume that in the case of a homestead strip or a mining strip, the owner/operator of the strip would be likely to have an elevation. CASA used to require air transport operators to have an ALA register which contained the strip details and phone numbers.
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