DUAT

"Steven P. McNicoll" wrote in message
nk.net...


An alternative clearance is issued when necessary to ensure separation
from other traffic or airspace. For example, if the controller had
traffic at nine thousand a proper clearance would be; "Climb to and report
reaching VFR-on-top, no tops reports. If not on top at eight thousand
maintain eight thousand and advise." Remember, you're just another IFR
aircraft until you report reaching and are cleared to maintain VFR-on-top.


It seems to be to everyone's advantage for the pilot to report being OTP as
soon as he is and can remain that way, even if that is on the runway, as
newps described, or on initial contact with Departure. That minimizes the
time and space during which I must be provided separation, as long as I am
willing to forego that.

"Steven P. McNicoll" wrote in message
ink.net...

"Stan Prevost" wrote in message
...

I have never received a clearance for just "VFR On Top" without further
restrictions, although I understand it is permitted. Restrictions can be
"Maintain VFR On Top at or below xxx", "....at or above xxx", or "... at
or between xxx and yyy".

I understand that the controller is not responsible for separation, so I
wonder why I always get an altitude restriction, usually "at or below".


Do you receive these restrictions after reporting VFR-on-top?

Sometimes yes, sometimes no.

Are you operating in airspace where ATC provides separation to VFR
aircraft?

Not to my knowledge. Not in Class B airspace nor Class C airspace.

Is Special Use Airspace a factor?

My flight path is always clear of SUA. Well, when I have received the OTP
restrictions, anyway. I always file a route that is clear of SUA, but
sometimes I get recleared enroute for direct destination (without request)
which puts me through SUA, and sometimes I get vectored around the SUA when
I get to it. Arghhh..

Stan Prevost wrote:
Then
another controller wouldn't let me descend in time (while I was still VFR On
Top), I wound up cancelling IFR and circling down to the airport.

Wouldn't let you descend? It's not his call. You tell him you're
descending, if you choose to tell him at all.



From your post, I learn that I should report OTP as soon as I am OTP and can
remain so, even if I have not reached the "report reaching" altitude.

The report reaching altitude is usually the top of that controllers
airspace. That way he is protected in case you don't break out. Here
we don't usually have clouds so you're on top while taxiing out.


Then
I should be cleared to just Maintain VFR On Top, and I can continue to climb
to my desired altitude. Is that right?

Right. As you break out just say "N123 is on Top at this time" and keep
right on climbing to whatever altitude you wanted.



It's been too long to remember the details, but once I left our local
airport in Class C and the controller would not clear me for OTP, or gave me
OTP below 10000, can't remember now. His reason had something to do with
he didn't own the airspace above 10000. Does that mean the controller must
restrict my clearance to something that will cause me to be contained within
his airspace?\

Yes. If there are no clouds just tell the ground controller or the
tower controller that you are on top at this time.

Stan Prevost wrote:



It seems to be to everyone's advantage for the pilot to report being OTP as
soon as he is and can remain that way, even if that is on the runway, as
newps described, or on initial contact with Departure. That minimizes the
time and space during which I must be provided separation, as long as I am
willing to forego that.

If you report it prior to departure the tower controller can amend your
clearance in the computer and this will save a landline call to the
center. Once you tag up on the radar the tower/departure controller
loses the ability to make changes in the computer, only the center can
do it.

"Newps" wrote in message
news


Stan Prevost wrote:



It seems to be to everyone's advantage for the pilot to report being OTP
as soon as he is and can remain that way, even if that is on the runway,
as newps described, or on initial contact with Departure. That minimizes
the time and space during which I must be provided separation, as long as
I am willing to forego that.

If you report it prior to departure the tower controller can amend your
clearance in the computer and this will save a landline call to the
center. Once you tag up on the radar the tower/departure controller loses
the ability to make changes in the computer, only the center can do it.

Interesting. I never heard that before. So a TRACON controller cannot
change a clearance without calling center to do it?

"Newps" wrote in message
news


Stan Prevost wrote:
Then
another controller wouldn't let me descend in time (while I was still VFR
On Top), I wound up cancelling IFR and circling down to the airport.

Wouldn't let you descend? It's not his call. You tell him you're
descending, if you choose to tell him at all.


Yes, I know, but when I have been given an instruction to advise of altitude
changes, and then when I advise of an altitude change and am told to remain
at my present altitude and he will give me lower in a few miles, my choices
are limited. I can start an argument on the frequency, cancel IFR,
disregard his instructions, or go along with what he says. There is that
pesky FAR that says pilots must comply with ATC clearances and instructions
(as long as they would not cause me to violate a FAR or compromise the
safety of my flight). Some say that pilots are not obligated to comply with
an instruction that an controller is not authorized to give, but that is
usually an issue to be sorted out on the ground, IMO.

If he wanted to keep me at altitude, he could have and probably should have
assigned me a hard IFR altitude, such as 12000 (I was at 12500). There is
not a lot of difference in the end result, so why cause a scene over it in
the air?

Newps wrote:


Wouldn't let you descend? It's not his call. You tell him you're
descending, if you choose to tell him at all.


Ok, how about the route aspect of VFR-On-Top? I know I'm supposed to fly
the route I was cleared for but what if ask for amended clearance?
Would it be easier to get it if I'm OTP instead of having a hard
altitude assigned? Here is why I'm asking - I few weeks ago on me and a
friend were on CEC-OTH-ONP route along the CA/OR coast in a C172. He
asked for direct to KONP and center said he could give it to him at 15
000 or higher, even though there was no significant terain all the way
north. Would it have been easier to get this if we were VFR-On-Top,
providing our own terrain and traffic separation? Of course, we could
have cancelled IFR but that would have meant that we would have needed
another clearance at our destination.

-ML

"Mark Hansen" wrote in message
...

The AIM says pilots SHOULD advise ATC prior to any altitude change when
operating OTP.

Sorry if I'm missing something, but aren't we talking about two different
flight modes here?

Over the Top is a VFR flight mode. You are not under IFR restrictions.

VFR On Top is an IFR clearance. You are under IFR restrictions and must
report changes in altitude (among other IFRs).


OTP is the contraction for "On Top". It is what ATC enters in an IFR flight
plan for aircraft that are operating VFR-on-top.

"Stan Prevost" wrote in message
...

OK, seems like reporting that I am OTP is part of the puzzle.


Depends on the situation. If you're cruising along on an IFR clearance and
request VFR-on-top the controller can simply clear you to maintain
VFR-on-top. It's assumed the conditions permit you to comply with the
clearance or you wouldn't have made the request. Once you've been cleared
to maintain "VFR-on-top," you are responsible to fly at an appropriate VFR
altitude, comply with VFR visibility and cloud clearance criteria, and
to be vigilant so as to see and avoid other aircraft. You're still
responsible to comply with instrument flight rules applicable to your
flight, such as adherence to ATC clearances. ATC will no longer provide
standard IFR separation, but will continue to provide traffic advisories.

Climbing through clouds in order to maintain VFR-on-top is another matter.
In that case ATC must provide standard IFR separation until you reach VFR
conditions and are cleared to maintain VFR-on-top. The controller won't
know those conditions exist until you report reaching them.



A few days
ago, I had requested 125/OTP. I intended to fly at 12500 while VFR On
Top, so I requested that. The controller seemed a little uncertain, said
he didn't have any tops reports. Finally he cleared me to "Climb to and
report reaching 12000, maintain VFR-on-top at 12000. If not on top at
12000 maintain 12 thousand and advise." It seemed wierd, but I decided to
climb on up and clear it up at altitude.


Bad phraseology. Assuming he had traffic at 13,000, the clearance should
have been; "Climb to and report reaching VFR-on-top, no tops reports. If
not on top at one two thousand maintain one two thousand and advise."



So I climbed to 12000 and
reported "VFR On Top at 12000". Then he told me to "Maintain VFR On Top
at 12000", as I recall, it might have been "at or below 12000".


Bad clearance. You can't maintain VFR-on-top at 12,000, VFR-on-top requires
flight at appropriate VFR cruise altitudes and 12,000 ain't one of 'em. The
controller shouldn't be instructing you to maintain any specific altitude at
all, even if it is a proper VFR altitude. If there is special use airspace
in use on your route, the controller must instruct you to operate at least
500 feet above the upper limit or 500 feet below the lower limit of the
airspace. Example, "Maintain VFR-on-top at least 500 feet below one three
thousand across Johnson East MOA between Smith and Jones VORs."



So I
asked him if I shouldn't be up at 12500, he stammered a bit, said stand
by, then came back and said to "Maintain VFR On Top at 12500 (might have
been 12500 or below, it has gotten fuzzy now)".


Still a bad clearance, should be just "Maintain VFR-on-top." You're
encountering controllers that are not very familiar with VFR-on-top.



It was a bit of a circus
the rest of the way on handoffs. One controller told me "For further
advisories contact XXX Center on YYY.ZZ", which I had not heard before
while on an IFR flight plan.


Should be just "Contact XXX Center on YYY.ZZ".



Then another controller wouldn't let me descend in time (while I was still
VFR On Top), I wound up cancelling IFR and circling down to the airport.


As long as you maintain VFR conditions he can't stop you from descending,
assuming you're not in airspace where ATC provides separation to VFR
aircraft and SUA is not a factor. To descend below the minimum IFR altitude
you'll have to either cancel IFR or be cleared for an approach of some kind.

Depending on where you're going the controller may have to assign a specific
IFR altitude. For example, let's say your destination is within approach
control delegated airspace where IFR aircraft on your route are assigned
eight thousand feet. You're still an IFR aircraft while operating
VFR-on-top so at some point the controller will instruct you descend and
maintain eight thousand or to cross a certain fix at eight thousand. Your
options are to comply or cancel IFR.



From your post, I learn that I should report OTP as soon as I am OTP and
can remain so, even if I have not reached the "report reaching" altitude.
Then I should be cleared to just Maintain VFR On Top, and I can continue
to climb to my desired altitude. Is that right?


That's right.



It's been too long to remember the details, but once I left our local
airport in Class C and the controller would not clear me for OTP, or gave
me OTP below 10000, can't remember now. His reason had something to do
with he didn't own the airspace above 10000. Does that mean the
controller must restrict my clearance to something that will cause me to
be contained within his airspace?


If the upper limit of his airspace is ten thousand an appropriate clearance
would be, "Climb to and report reaching VFR-on-top, no tops reports. If
not on top at one zero thousand maintain one zero thousand and advise."
Remember, you're treated the same as any other IFR departure until you
report reaching VFR conditions and are cleared to maintain VFR-on-top. If
your requested altitude had been 14,000 the departure controller would have
cleared you to 10,000 and told you to contact center while you were still
climbing to ten thousand. You'd contact center and he'd climb you to
fourteen thousand. It works the same way if your requested altitude is
VFR-on-top and you haven't reached VFR conditions by ten thousand, you'd
have to get a higher altitude from center.

"Stan Prevost" wrote in message
...

Yes, I know, but when I have been given an instruction to advise of
altitude changes, and then when I advise of an altitude change and am told
to remain at my present altitude and he will give me lower in a few miles,
my choices are limited. I can start an argument on the frequency, cancel
IFR, disregard his instructions, or go along with what he says. There is
that pesky FAR that says pilots must comply with ATC clearances and
instructions (as long as they would not cause me to violate a FAR or
compromise the safety of my flight). Some say that pilots are not
obligated to comply with an instruction that an controller is not
authorized to give, but that is usually an issue to be sorted out on the
ground, IMO.

If he wanted to keep me at altitude, he could have and probably should
have assigned me a hard IFR altitude, such as 12000 (I was at 12500).
There is not a lot of difference in the end result, so why cause a scene
over it in the air?


You're dealing with a controller unfamiliar with VFR-on-top. Separation is
not an issue so there's no reason to keep you at altitude.