Obstacle departure procedure when VMC? (part 121)

What guarantees you terrain clearance here? Tower has no ability to do that.

Good point. If you switched to departure, and departure says "cleared direct XYZ" and you are only at 2000ft, would you assume departure is ensuring terrain clearance?
 
Good point. If you switched to departure, and departure says "cleared direct XYZ" and you are only at 2000ft, would you assume departure is ensuring terrain clearance?

Yes, I would make that assumption, if I had heard "radar contact". I would point out, though, that this whole subject is poorly documented. Who is responsible for terrain clearance at any given time is very fuzzy, so I think it pays to be very, very cautious regarding assumptions. There was one jet CFIT after the pilot *requested* direct, which the controller gave. The NTSB said that the pilot requesting direct relieved the controller of ensuring terrain clearance along the route. Where is that published?

BTW, your question regarding the meaning of "when able" is astute. The Instrument Flying Handbook gives two contradictory explanations of what it means. Even so, I would consider neither authoritative. What's important is what the controller you're talking to *thinks* it means.
 
The question of when a tower operator can turn you comes up very often in our operation and everyone seems to have their own opionion. I have heard the argument that if tower instructs you to turn to XYZ you are required to do so before completing the ODP since you may not deviate from a clearance. Thoughts on this? Can a tower operator ever ensure your terrrain clearance?
 
I've seen another version of this scenario when I used to fly out of State College, PA. There is an ODP regarding runway heading until 2600 ft. Many times when departing from there and contacting ATC (SCE is uncontrolled, a topic for another time) we were told "terrain and altitude permitting, turn left heading 340."
 
Can a tower operator ever ensure your terrrain clearance?

Some tower guys claim to be issuing a "relayed vector" from the approach control, but I have seen nothing published from the FAA endorsing this point of view. How can a vector be issued without radar contact? Tower guys say that during a takeoff, they *know* where the aircraft is.....right off the departure end of the runway!

Some of the following articles are pertinent to this discussion:

http://www.terps.com/ifrr/may95.pdf
http://www.terps.com/ifrr/nov95.pdf
http://www.terps.com/ifrr/feb97.pdf
http://www.terps.com/ifrr/apr98.pdf

And to show you that the question you asked has risen to the top levels within the FAA, you might find the following discussion interesting:

http://www.faa.gov/about/office_org...0/afs420/acfipg/open/media/Hist 07-01-269.pdf

It's the minutes of a meeting of an FAA working group. One paragraph reads:
Also under discussion was when pilots should make the turn to an assigned ATC departure heading. Bill Hammett, AFS-420 (ISI), used the textual ODP for runway 35 at Manchester, NH (KMHT) as an example that has been under discussion in the New England Region. The ODP states to “....climb runway heading to 1200 before proceeding westbound...” Controllers frequently issue “...left turn to XXX, cleared for takeoff”. Does the pilot turn at 400’ AGL or climb to 1200 before taking the turn?

Unfortunately, there was no Terminal Service Unit representation at the meeting to participate in the discussion. Tom Schneider, AFS-420, as Chair of the ACF-IPG, took an IOU to send the agenda item and initial discussion to the Terminal Safety and Operations Support Office, AJT-2 requesting a response and participation in future meetings. ACTION: Chair, ACF-IPG and AJT-2.
 
That also needs to be treated with caution. Not all tower controllers and/or departure controls are *capable* of ensuring terrain clearance for you. If there's a DVA around the airport, fine and dandy, but there aren't many of those and no one tells pilots where they are.

In which case you fly the ODP for the airport. Most of the time however, we get issued a SID or a heading after departure. In these cases ATC takes responsibility for terrain clearance. If it's VFR, we routinely ask for a VFR climb direct XXX and usually get it.
 
A good example of all this is taking off from Bozeman, MT headed south to SLC. There's a funky bow-tie DP that sends you out one radial up 4000 feet or so, then back to the VOR on the airport before turning south. Center radar doesn't pick you up till around 11,000'. You'll be "cleared as filed" which is direct south on the airway. Tower gets a release from center, and clears you for takeoff with no turn instructions. What do you do?

In VMC, I'm headed south with the terrain in sight climbing to the first fix (making sure to meet the MCA). If I can't see the terrain, I'm doing the ODP.
 
Three times tonight (already) I got "cleared for takeoff" without an accompanying heading to fly or route. I flew the ODP as published each time.

When checking on with departure, I got "radar contact cleared direct ABC". My response was: "mini-tard 123 we'll be direct momentarily". No problems at all.

I say fly the ODP if you can't visually avoid the obstacle(s).

-mini
 
What do you do when tower wants you to make a turn early for traffic? Like I said, when they use the words "dierct XYZ when able" I fly the complete ODP.

I operate out of several airports with ODP's and often the tower seems confused why I take so long to turn on course. This fact, combined with the fact that many of the people I fly with don't know that the ODP is mandatory even VMC leads me to believe there is a lot of confusion on this issue.
 
FWIW: Flying out of North Las Vegas (VGT) on the ODP at night the approach controller has given me the choice along the lines of. . . "if you can maintain obstacle clearance, cleared direct PGS VOR". I have always been "unable" and stayed on the ODP, which has never been a problem. They have usually come back a few minutes later with "cleared direct PGS VOR", which I have always assumed to mean that they now are accepting responsibility for obstacle clearance.
 
A good example of all this is taking off from Bozeman, MT headed south to SLC. There's a funky bow-tie DP that sends you out one radial up 4000 feet or so, then back to the VOR on the airport before turning south.

That ODP sucks! It was designed for a 125kt aircraft...it's ugly in a CRJ no matter what.

Center radar doesn't pick you up till around 11,000'. You'll be "cleared as filed" which is direct south on the airway. Tower gets a release from center, and clears you for takeoff with no turn instructions. What do you do?

If it's VMC, I will *always* tell tower that we would like a "VMC Climb to xxx [fix]". If you're on an IFR flight plan, I've been told (by my training department) that it's essential to fly the ODP unless you're specifically cleared for a VFR climb. With that in mind, I make sure not only ask for the VMC climb but also ensure we're clear on the altitude/fix to which I'm climbing VFR.
 
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