Allen (and others)
Yes, learning is way better than laundry.
I don’t know why the controller would release somebody when I’m fairly close to the airport descending with an on top or VFR descent clearance, all I know is they have. I’ve always assumed from this experience that normal IFR separation minimums are either completely waived or at least highly changed. If I could find my copy of the AIM I could look all this up. Where I work now the VFR climbs and descents are not a part of the vocabulary so I haven’t really thought about it recently. All of what I am relating comes from 15 years of flying pistons and then turboprops on the west coast and just comes from my recollections of those days.
If I say I’m VMC the controller has to take my word for it, after all he may be sitting in a box 200 miles away. No different from me requesting a visual approach from a controller who is remotely located, he has to take my word for it too. He might have reported wx to back up my request, but who’s to say that the fog hasn’t cleared up in the last 5 minutes and I really can see the airport from 5 miles away?
By VFR climb I’ve always taken it that I have told ATC I am in VMC conditions and will be that way up to my filed altitude (or 18,000 ft). I’m also responsible for my own terrain separation. For instance at the near sea level airport I used to fly out of we had a few hills around that pushed MEAs to at least 5000 ft., 9000 in one case. The DP was this round-about thing that added 20 miles to your flight if you were going the other way. During the summer we got a lot of marine layer fog which required picking up a clearance on the ground. After climbing through the fog layer and reaching VMC we would request a “VFR climb, direct XYZ VOR” which would always be approved. Sometimes you reached sunshine by 1500 ft. so the time savings was significant. If there was another aircraft waiting to depart they would immediately be released. Same if someone was holding for the approach, they would get an immediate approach clearance. (hopefully not at the same time!) If I didn’t request a VFR climb (or on top, and canceled IFR) the next airplane might have to wait an extra 5 minutes.
As far as climb rates go, yes I do think the minimum climb gradient, and any other DP restrictions would still apply as long as you are still flying a published route and not doing the direct or on course climb.
One time, before Santa Barbara approach control got their radar, I was sitting there waiting to head home, it was foggy. A United flight called up for his clearance to Bakersfield and by the way do you have a tops report? SBA: Yes, the tops are 3000 ft. United: OK, in that case we are requesting a VFR climb from 4000 to 11,000. SBA: (short version) Cleared to BFL via (I forget the SID) except climb VFR from 4000 to and maintain 11,000, reaching 4000 climb on course direct BFL VOR. etc. So, in a non-radar environment they got the SID waived after reaching 4000’ which let them turn directly towards a 5000’ mountain (8000’ a few more miles down the road). All because they were going to be in VMC conditions. Of course if the weather changed there would be a mad scramble to change the clearance at the last second and continue with the full SID.
The one time this wouldn’t work is if I’m in a 172, filed to cruise at the MEA, and the airplane waiting to depart behind me is a higher performance airplane flying the same route. Once I reach the MEA the VFR climb is finished and I’m back on a full IFR clearance, the controller anticipates this and has no place to put the higher performance guy and so has to wait for whatever the normal separation would be.
As you say, I hope a controller chimes in here. I think that from a practical point of view the VFR climb (or descent) relieves the controller from separation but keeps the IFR flight plan alive for things like flow control at the destination or future IMC operations without needing to re-file. Other than expediting things it doesn’t really do much for me.
I forget who it was but it was suggested that the controller can arbitrarily cancel your IFR flight plan if you want to go sightseeing (or for any other reason). I don’t think they can, it has to be done by the pilot if in the air. The only time it is canceled for you is after landing at a controlled airport.
As far as MEAs go, what ever is appropriate for the location is correct, I just didn’t feel like typing all of them in. Sightseeing in some areas and not in others, yes, absolutely. I can’t imagine a controller being to thrilled to let you descend and take pictures of the Rose Bowl while keeping your IFR flight plan.
Uh, lets see, what else. Oh, traffic count. All I know is what he told me. A visual approach should count. I think departing and then picking up the clearance wouldn’t help the count for the airport because you picked up the clearance in the air. maybe, not sure about that.