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Destination Airport not Served by Approach
Center/Tower/Ground – You will experience simple step descents, and no crossing restrictions. At 60 miles from destination, Center will ask if you have the arrival weather, and which approach you are planning on. Sub menus appear, making answering these questions very easy. You will be handled with respect to your answers. If at 60 miles you told Center you would like a visual, you can at anytime change your mind and request a specific precision or non-precision, IAP approach. An IAP approach means you fly “the full” approach with no assistance from the controller. RC does not tell you how to fly an IAP approach. You will need those plates. Or, if at 60 miles you requested an IAP but see the airport as you near the area, request a Visual. Center only – You will experience simple step descents, and no crossing restrictions. You can make an IAP approach request as early as 60 miles out if you wish, or hold out a bit while you watch for the airport to come into view. Do not forget that arrival weather as you get closer to your destination.
Pilot Discretion Descent Clearances
I have heard time and time again, “I was given some altitude, then I was told to cross X miles at a different altitude. Does this mean I should wait until 40 miles out before descending? Do I have to start down now? Which altitude do I descend to?” These are excellent questions. Fact: Your most recently received control clearance supersedes all other clearances. Example: You have been given “…PD to FL190”, then later the controller says “…descend and maintain FL180”. FL180 is now your assigned altitude. FL190 is no longer of any consequence, and “descend and maintain” means now. This is a totally different clearance that negates the PD FL190 clearance. Again, your most recently received control clearance supersedes all other clearances.
Radar Contact ATC Basics
Version 4 December 2, 2007
Copyright JDT LLC 2005 Page 48
We issue PD clearances because we are very aware of the cost benefits that “staying high” yields (less fuel burned). If you are told to “…descend at pilot‟s discretion maintain FL190…”, then later get “…cross four zero miles from (fix) at 11,000 ft/250 kt…” FL190 is no longer in the picture. That is no longer your assigned altitude. 11,000 is your assigned altitude. Further, a crossing restriction is a pilot’s discretion descent clearance. This is very unlike a “…descend and maintain…” altitude clearance where descent is required. What does that mean to you? Given that a crossing restriction is a PD clearance, you are welcome to level off at FL190 or any other altitude without fear of annoying the controller. However, you need to plan whether to level off somewhere (optional), adjust your descent rate, all respect to your speed, based on the requirement that you have to be at your newly assigned altitude (in this case „one one thousand‟, or 11,000 ft), at or before whatever point ATC gave you in the crossing restriction. This usually means 40 miles from your final checkpoint. You have to be level at the assigned altitude, at or before reaching this point. If you wait until 40 miles out to begin your descent you will be told to start a descending 360 degree turn until you are at the right altitude, or you will be given a series of vectors until you have met your crossing restriction altitude. Controllers, not FMCs, determine when initial descents are started but those using FMCs will like this! While at cruise altitude and when you get your 1st descent clearance you will notice the menu item “3-PD”. Use this feature to request a “Pilot‟s Discretion Descent”. The RC controller will approve or deny this request depending on varying circumstances. Use wise judgment in making the call when to start down! If approved, RC will not issue the “expect” clearances for crossing restrictions that normally come on Low‟s frequency, but you can bet some sort of restriction will be given. IMPORTANT NOTE – Your co-pilot will always acknowledge any clearance to descend from cruise, thus forcing you to begin descent. If you wish to use this feature, be sure you are doing the talking.
Many such questions and topics are regularly discussed on our AVSIM forum (www.avsim.com). If you prefer, email doug@jdtllc.com directly. Where possible, these emails will be addressed individually. If Doug directs you to the forum, do not be shy. There is a reason, most likely that many can learn from this topic. The only silly question is the question not asked.
Crossing Restrictions
If your destination airport has an Approach Controller, expect a crossing restriction. Depending on several factors, you will hear one of these two types of restrictions:
“…cross four zero miles from XXX at (altitude), two five zero knots (if applicable)…”
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