Being asked to "verify direct XXX"

"Bob Gardner" wrote in message
...

ATC can't see your heading, just your ground track. They would have no way
of knowing that you are off-course by a "couple of degrees."


Sure they do. If the observed track is other than the cleared route the
aircraft is off course.

Nitpick, Steve. This is another example of a pilot thinking that ATC sees an
image of the airplane rather than a data block.

I'll be at the NATCA meeting in May...will you? I'm neither a controller nor
a NATCA member, but I go anyway.

Bob Gardner

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

"Bob Gardner" wrote in message
...

ATC can't see your heading, just your ground track. They would have no
way of knowing that you are off-course by a "couple of degrees."


Sure they do. If the observed track is other than the cleared route the
aircraft is off course.

"Bob Gardner" wrote in message
...

I'll be at the NATCA meeting in May...will you?


Nope.



I'm neither a controller nor a NATCA member, but I go anyway.


Why?

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

"Bob Gardner" wrote in message
...

I'll be at the NATCA meeting in May...will you?


Nope.



I'm neither a controller nor a NATCA member, but I go anyway.


Why?


Because it isn't just a NATCA meeting...

Chip, ZTL

Bob Gardner wrote:

ATC can't see your heading, just your ground track. They would have no way
of knowing that you are off-course by a "couple of degrees."

The only way ATC notices a 2 degree error is if where you are supposed
to be going happens to follow an airway.

My take is direct gives you the same horizontal and vertical tolerances
that an airway does. Which I think, is 100' of altitude variation
(actually they don't usually see it, unless it is 150' or more), and 2
miles to the right or 2 miles to the left.

However it ATC sees you are veering off course, the controller can ask,
as a way of getting your attention to the deviation (even though it may
still be withing tolerances). He sees you are veering off course and
wants you to correct. But that doesn't mean you have busted your
clearance.

Take ATC statements for what they say. He wants you to verify that you
are direct.

Also, don't get in the habit of hitting the direct to button, you
should actually fly back to your course and get back on your original
direct track, not keep making new direct to tracks.

If you do a lot of IFR flying, get the Howie Keefe (www.aircharts.com),
text updates. You can use these to see if any of the waypoints have
changed if you update your GPS when the Keefe system begins (March I
think). This way you will know if your waypoints are up to date, even
though the database may not be.

Newps wrote in message ...

The only way ATC notices a 2 degree error is if where you are supposed
to be going happens to follow an airway.



No, a controller can also compare the track to the route readout.

Paul Folbrecht wrote in
:

Anyway, on to my question. A couple times now, when I've been
navigating direct, either to a fix or airport identifiable by VORs or
one that isn't (such as an uncontrolled field with no navaid), I've
been asked to "verify direct XXX" when I'm off course by a quite small
amount - no more than 10 degrees. Or, perhaps, I've gotten off course
a bit and have a larger heading correction (20-25 degrees) in to get
back on track, momentarily. I've never had a controller sound
annoyed, but it does concern me a bit that they see fit to more or
less ask "Are you sure you know where you're going"??

Was it the same controller who gave you the clearance?

How far off course were you with respect to miles, not degrees?

Especially during controller changes and/or handoffs, controllers may
not always have clearly documented the last clearance they gave you. The
next controller confirms this either by asking you to verify, or giving
you the clearance again. I've had this happen to me numerous times.

Generally speaking, though, I have found that a "correction" will only
be made if you are off by more than a couple of miles and don't seem to
be correcting, or if your error threatens to cause separation issues
(although this is more common with altitude busts than heading busts).

I look at it as a good thing, not a bad one. One time when flying IFR
in IMC I managed to miss a waypoint on an airway. As I flew off the
"real" airway I was asked to verify I was on the airway. When I
confirmed they indicated that I looked like I was direct to the next
waypoint (I think it was RBV or SAX VOR) and not on the airway. When I
realized the error and fessed up, they cleared me direct to where I was
going anyway - presumably no one else was around, and it was only a few
degrees different. But had there been other traffic in the area, and had
they not corrected me (ie: RADAR down or what not), it could have led to
bad things...

Accidents happen, people are only human and do make mistakes. That's why
ATC is not annoyed to help you. They're there to help you. They will get
annoyed if they have to correct you frequently (READ: NY TRACON if it's
more than once, or if they just corrected someone else before you). But
everyone gets an occassional correction - I've even heard it happen to
Heavies!