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Minimum Climb Gradient Calculation Speed

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Minimum Climb Gradient Calculation Speed

Old 2nd Jun 2012, 11:32
  #21 (permalink)  
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Why doesn't the ROC formula work when you are coming down?

ah .. now, what percentage gradient is 3 degrees equivalent to ? .. and what does 10/2 equal ?
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Old 3rd Jun 2012, 00:38
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Hmmm.

So you get a SID in your brief that has a minimum climb gradient...how do you know you can comply?

Next time your flying your Airbus or 747, look to your right or left under the window, there is usually a big white book, it's called a Flight Manual. Give it look, some great information in there.

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Old 3rd Aug 2012, 00:15
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Because ROC on Approach is not the GPA. Simplistically, it is 1 degree below the effective GPA, and begins at the threshold crossing at 200'ROC (yes, below ground)
The FAA model is very simple, it assumes a 3 degree GPA, a 200' ROC, originating at a straight line down at the threshold, sloping up at 2 degrees until it is a 500' ROC, that is the location of the FAF...
its just that simple...
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Old 3rd Aug 2012, 01:33
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FlightPathOBN:

Because ROC on Approach is not the GPA. Simplistically, it is 1 degree below the effective GPA, and begins at the threshold crossing at 200'ROC (yes, below ground)
The FAA model is very simple, it assumes a 3 degree GPA, a 200' ROC, originating at a straight line down at the threshold, sloping up at 2 degrees until it is a 500' ROC, that is the location of the FAF...
its just that simple...
The FAA uses the ICAO model for ILS and LPV and obviously the terminating ROC is not 200 feet.
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Old 3rd Aug 2012, 03:36
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here we go again...

okay, go to the FAA supplied worksheet.
in the block, distance of obstacle from LTP put 0...

what is the ROC at the LTP?

200.

Last edited by FlightPathOBN; 3rd Aug 2012 at 03:49.
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Old 3rd Aug 2012, 14:16
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You must have a worksheet for something else.
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Old 4th Aug 2012, 13:10
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FlightPathOBN:

here we go again...

okay, go to the FAA supplied worksheet.
in the block, distance of obstacle from LTP put 0...

what is the ROC at the LTP?

200.
The ROC for an ILS at the LTP is zero with a normal ILS installation.

The ROC at the 200-foot DA point on a 3 degree slope beneath the "W" OCS is approximately 121 feet. (Calculated from Volume 3 of FAAO 8260.3B, not a worksheet).
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Old 6th Aug 2012, 04:46
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if you know what the gradient is you will know what speed.it is actual speed (GS.).

Last edited by Noknoipobin; 6th Aug 2012 at 04:51.
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Old 8th Aug 2012, 12:55
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Without getting into it there's lotsa horse hooey in this thread spouted by non-engineers Jetpipe non sequitur

pilots....Read the flight manual...

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