Pilot Switch Freq On Own

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geoffist
Posts: 3
Joined: Wed Oct 19, 2016 5:12 pm

Pilot Switch Freq On Own

Post by geoffist »

Hey gang!

I am curious about when a pilot can change frequencies on their own, severing contact with the ATC that they were previously in contact with.
I have been told many times that there are three times they can change frequencies without being told to do so by the ATC:
1) After clearance delivery has said “readback correct” (DEL to GND frequency)
2) Upon reaching the assigned departure runway (GND to TWR frequency)
3) A VFR departure leaving a Class D airspace (TWR to whatever/CTAF/UNICOM/another TWR/ATC)

These all make sense but I would like to see where in the regulations (FAR) or AIM that it says this or how one would come to this conclusion without being told so. Can anyone point me in the right direction to read up on this? I have looked in the “Radio Communications” sections of both FAR and AIM but I’m either missing it or its not there.
There are also some issues with #2… I have heard ATC on PE say that they have witnessed pilots switching to TWR frequency WAY too early prior to reaching their assigned runway. So, where is it stated of WHEN/WHERE they can change to that TWR freq?
Also, what if the pilot got setup with VFR Flight Following (radar services) on the ground by Ground or Delivery and takes off from a Class D airspace, but the ATC are REALLY busy (can’t get a word in edgewise), once the pilot leaves the Delta airspace, can they change frequencies on their own still?

Thanks for all your help!
HotMike
Posts: 2
Joined: Tue Apr 11, 2017 11:59 pm

Re: Pilot Switch Freq On Own

Post by HotMike »

1 and 2) AIM 4-3-14a - "Pilots of departing aircraft should communicate with the control tower on the *appropriate* ground control/clearance delivery frequency [blah blah]. Unless otherwise advised by the tower, remain on that frequency during taxiing and runup, then change to local control frequency when ready to request takeoff clearance.

The appropriate frequency means that, unless you are told to maintain clearance delivery, your appropriate frequency to request taxi is ground. At some quieter airports with clearance delivery, they'll announce "contact ground when ready to taxi" after "readback correct".

When you are given taxi instructions to a runway, you then are in the ballpark of "local control frequency when ready to request takeoff clearance". The logic I was taught was - the AIM states stay with ground/clearance (ground usually since clearance at most only handles gate pushback and not taxi) through *runup*, and runup areas (on airports where they exist) are usually holding short of the runway. The AIM then says contact the Local Control Fac. (aka Tower) once you're ready to go. So, unless otherwise stated, contact tower holding short outside of the runup area (after runup, since ground controls the runup) and only when ready for takeoff clearance. If you're runup complete prior to taxi/don't need a runup, then your taxi clearance likely takes you "to" a runway (AIM 4-3-18a6), which is holding short, then you should switch to tower when "ready to request takeoff clearance". Can't be ready unless you're close enough to accept an immediate departure clearance either. So, holding short or in the line of people ready to go.

3) AIM 3-2-5b4a - "Two-way radio communications must be established and *maintained* with the control tower, and thereafter as instructed by ATC while operating in the Class D airspace.

There are very few Class D airports in real life (I've found) that operate like on PilotEdge. Most of them seem to think that they are LaGuardia and want more control over you than any Class C or B I've flown in and will usually issue freq change instructions or wait for you to request a freq change. Regardless - they've cleared you to head out, and while you're not "approved" to change frequencies per say, you are no longer obligated to talk to the tower once you leave their airspace.

This links up with your final question, yep. Once you are clear of the D, head on over to your flight following freq. Same thing applies in C and B (AIM 3-2-3d2b says Class B ATC will "normally advise VFR aircraft when leaving [sic] Class B airspace"), though towers are typically much better at throwing you over to departure within the B/C to lower their workload while you're still in the B/C airspace and thus must maintain radio communications.

As for flight following, to simplify, when I am looking for VFR flight following in the real world (B,C or D), I almost exclusively just contact ARTCC once leaving the airspace with no pre-coordination prior to takeoff. Seems to make things easier, and if the ARTCC is too busy to oblige, I don't have any pre-dispositions about whether or not I'm getting it or not before I roll out. After all, Flight Following is ATC workload permitting (AIM 4-1-15b1).

Hope this helps!

Mike
Kyle.Sanders
Posts: 819
Joined: Sat Jan 18, 2014 5:13 pm

Re: Pilot Switch Freq On Own

Post by Kyle.Sanders »

VERY GREAT and DETAILED response Mike!
HotMike wrote: This links up with your final question, yep. Once you are clear of the D, head on over to your flight following freq. Same thing applies in C and B (AIM 3-2-3d2b says Class B ATC will "normally advise VFR aircraft when leaving [sic] Class B airspace"), though towers are typically much better at throwing you over to departure within the B/C to lower their workload while you're still in the B/C airspace and thus must maintain radio communications.
Keep in mind that when in Class C or B airspace, chances are that you are under radar services (even when not asking for it), except in rare circumstances.

AIM 4-1-15.b.2 says that you will need to stay on the frequency of the controller while you are under radar services (you have been advised: "Radar Contact")
"When receiving VFR radar advisory service, pilots should monitor the assigned frequency at all times. This is to preclude controllers’ concern for radio failure or emergency assistance to aircraft under the controller’s jurisdiction."
Kyle Sanders
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