Minimum Climb Gradient Calculation Speed
Fleet Manager
Joined: Apr 2001
Aviation Qualifications: ATPL
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From: various places .....
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 ?
ah .. now, what percentage gradient is 3 degrees equivalent to ? .. and what does 10/2 equal ?
Joined: May 2012
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From: Earth
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.
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.
Joined: Mar 2011
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From: engineer at large
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 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...
Guest
Joined: Apr 2009
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From: On the Beach
FlightPathOBN:
The FAA uses the ICAO model for ILS and LPV and obviously the terminating ROC is not 200 feet.
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 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...
Joined: Mar 2011
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From: engineer at large
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.
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 August 2012 at 03:49.
Guest
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From: On the Beach
FlightPathOBN:
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).
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.
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 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).
