Ok embry grads

Old kodger needs some thoughts

There is the Standard Press for a Elev

Say 1000 elev above MSL would be 28.92

And then calculate Actual Press Alt

at 1000 airport elev with a reported alt setting at the field of 30.92 which would calculate out to be negative 1000 below msl for the Actual Press Alt

(-1000)

Am I correct so far?

Now calculating Density Alt

Most online calculators ask for the elev, temp, dew point and reported alt setting.

Formula

DA = PA + (120 x difference between OAT and ISA)

Question

If figuring it out with your trusty dusty calculator....

in the formula, PA is the actual calculated PA, not the uncalculated field elevation. Correct?

in the formula ISA is what the ISA should be at the actual calculated PA, not the ISA for the airport elevation. Correct?

Why I ask.... In the calculators online, for example http://www.pilotoutlook.com/calculators/density-altitude-calculator

it asks for Elevation, Air Temp, Alt Setting and Dew point.

I think I should be putting in the Corrected Press Alt not the elevation, the actual ATIS reported Temp, Alt Setting and Dew Point

But I imagine in their online formula it figures out the Corrected Press Alt then The Density Alt and then only outputs the Density Alt

Forgive the old Cave Man... in the real world for example in the old DC-8-54 as a FE you had about 5 or 6 charts to go through step by step connecting the dots so you didn't really have to think about it and then the other guy checked your figures and then with the ACARS unit = Brain Dead.

Now I gotta re-learn all this stuff to make sure when flying the little ones again

And I may have this all wrong.

Old kodger needs some thoughts

There is the Standard Press for a Elev

Say 1000 elev above MSL would be 28.92

And then calculate Actual Press Alt

at 1000 airport elev with a reported alt setting at the field of 30.92 which would calculate out to be negative 1000 below msl for the Actual Press Alt

(-1000)

Am I correct so far?

Now calculating Density Alt

Most online calculators ask for the elev, temp, dew point and reported alt setting.

Formula

DA = PA + (120 x difference between OAT and ISA)

Question

If figuring it out with your trusty dusty calculator....

in the formula, PA is the actual calculated PA, not the uncalculated field elevation. Correct?

in the formula ISA is what the ISA should be at the actual calculated PA, not the ISA for the airport elevation. Correct?

Why I ask.... In the calculators online, for example http://www.pilotoutlook.com/calculators/density-altitude-calculator

it asks for Elevation, Air Temp, Alt Setting and Dew point.

I think I should be putting in the Corrected Press Alt not the elevation, the actual ATIS reported Temp, Alt Setting and Dew Point

But I imagine in their online formula it figures out the Corrected Press Alt then The Density Alt and then only outputs the Density Alt

Forgive the old Cave Man... in the real world for example in the old DC-8-54 as a FE you had about 5 or 6 charts to go through step by step connecting the dots so you didn't really have to think about it and then the other guy checked your figures and then with the ACARS unit = Brain Dead.

Now I gotta re-learn all this stuff to make sure when flying the little ones again

And I may have this all wrong.

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