Non-towered airport departure, when to turn on course?

OverTQ

Pre-takeoff checklist
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OverTQ
Let's say you are departing from a non-towered (Class G) airport. You pick up your clearance and then switch to CTAF. You chose to fly an ODP.

When can you break off the ODP and turn direct to the first point in your flight plan? Do you have to fly either the whole thing, or non at all?
 
Fly the ODP then do whatever ATC instructs you to do after getting radar contact.
 
As a Part 91 operator, unless he controller includes the ODP in your clearance, you don't even have to fly the ODP if you don't feel like it. Likewise, unless he controller includes the ODP in your clearance, you can break off from the ODP any time you feel like it. However, if you choose to either not fly the ODP or break off from it before reaching its termination, you lose your guarantee of obstacle clearance, so choose wisely. OTOH, a commercial operator has no choice but to fly the ODP to its termination point unless given some other clearance by ATC.
 
Still a very good idea to stay on the ODP unless you have good visibility with whatever the O was that they established it.
 
Let's say you are departing from a non-towered (Class G) airport. You pick up your clearance and then switch to CTAF. You chose to fly an ODP.

When can you break off the ODP and turn direct to the first point in your flight plan? Do you have to fly either the whole thing, or non at all?
I'd say if it's not part of your clearance....no, you don't have to fly the whole thing or not at all. For example if part way thru' you break out in the sunshine on top you could break it off and intercept your enroute course if you wanted. OTOH like flyingron said, if clouds and/or visibility is still an issue you'd be well advised to stay on the ODP.
 
I'd say if it's not part of your clearance....no, you don't have to fly the whole thing or not at all.
That's true for noncommercial operations, but not for commercial operators like 121 and 135 -- they are required to follow any applicable ODP even if it's not part of the ATC clearance. But as Ron and I said earlier, if you choose not to follow it, you'll lose your guarantee of obstacle clearance, so be very cautious about doing this in anything but good day VFR conditions.

For example if part way thru' you break out in the sunshine on top you could break it off and intercept your enroute course if you wanted. OTOH like flyingron said, if clouds and/or visibility is still an issue you'd be well advised to stay on the ODP.
Even if clouds/visibility aren't an issue, you'd still be wise to think about why they put that ODP out there -- which is done only when there are obstacles to the "standard" AIM 5-2-8b1 departure, so if there is an ODP published, you know there's something to watch out for.
 
That's true for noncommercial operations, but not for commercial operators like 121 and 135 -- they are required to follow any applicable ODP even if it's not part of the ATC clearance. But as Ron and I said earlier, if you choose not to follow it, you'll lose your guarantee of obstacle clearance, so be very cautious about doing this in anything but good day VFR conditions.

Got a reference for that, Ron?

Granted, I've only dealt with turbine ops for the last 15 years, but the only requirement there is to clear obstacles by the specified amounts in 135.379 or the 121 equivalent. Whether you do that via the published ODP or some other custom procedure is up to the operator.
 
Got a reference for that, Ron?

Granted, I've only dealt with turbine ops for the last 15 years, but the only requirement there is to clear obstacles by the specified amounts in 135.379 or the 121 equivalent. Whether you do that via the published ODP or some other custom procedure is up to the operator.

This is probably what he's thinking of:

§91.175 Takeoff and landing under IFR...

(f) Civil airport takeoff minimums. This paragraph applies to persons operating an aircraft under part 121, 125, 129, or 135 of this chapter...

(3) Except as provided in paragraph (f)(4) of this section, no pilot may takeoff under IFR from a civil airport having published obstacle departure procedures (ODPs) under part 97 of this chapter for the takeoff runway to be used, unless the pilot uses such ODPs or an alternative procedure or route assigned by air traffic control.

(4) Notwithstanding the requirements of paragraph (f)(3) of this section, no pilot may takeoff from an airport under IFR unless:

(i) For part 121 and part 135 operators, the pilot uses a takeoff obstacle clearance or avoidance procedure that ensures compliance with the applicable airplane performance operating limitations requirements under part 121, subpart I or part 135, subpart I for takeoff at that airport; or

(ii) For part 129 operators, the pilot uses a takeoff obstacle clearance or avoidance procedure that ensures compliance with the airplane performance operating limitations prescribed by the State of the operator for takeoff at that airport...
 
Let's say you are departing from a non-towered (Class G) airport. You pick up your clearance and then switch to CTAF. You chose to fly an ODP.

When can you break off the ODP and turn direct to the first point in your flight plan? Do you have to fly either the whole thing, or non at all?

I don't think you have to at all (assuming non commercial here, then you have no choice), but without knowing the terrain, I would be selective on choosing that option.
 
I would say that if you get to MEA/MSA/MORA or other safe altitude prior to reaching the end of the ODP, it would be safe to proceed on course.
 
That's true for noncommercial operations, but not for commercial operators like 121 and 135 -- they are required to follow any applicable ODP even if it's not part of the ATC clearance.

This below seems to contradict that

This is probably what he's thinking of:

§91.175 Takeoff and landing under IFR...

(f) Civil airport takeoff minimums. This paragraph applies to persons operating an aircraft under part 121, 125, 129, or 135 of this chapter...

(3) Except as provided in paragraph (f)(4) of this section, no pilot may takeoff under IFR from a civil airport having published obstacle departure procedures (ODPs) under part 97 of this chapter for the takeoff runway to be used, unless the pilot uses such ODPs or an alternative procedure or route assigned by air traffic control.

(4) Notwithstanding the requirements of paragraph (f)(3) of this section, no pilot may takeoff from an airport under IFR unless:

(i) For part 121 and part 135 operators, the pilot uses a takeoff obstacle clearance or avoidance procedure that ensures compliance with the applicable airplane performance operating limitations requirements under part 121, subpart I or part 135, subpart I for takeoff at that airport; or

(ii) For part 129 operators, the pilot uses a takeoff obstacle clearance or avoidance procedure that ensures compliance with the airplane performance operating limitations prescribed by the State of the operator for takeoff at that airport...
 
Contradicts? No, I don't think so -- that section says pretty clearly that commercial operators are required to use the ODP unless ATC says otherwise. My reference to an ATC clearance in the post you quoted had to do with the difference for commercial operators from noncommercial operators, who are free to do what they want unless ATC makes the ODP part of their clearance.

To summarize...

If an ODP exists for the airport of departure, commercial operators must fly the ODP unless ATC says otherwise, but noncommercial operators are free to do what they want unless ATC says otherwise.

Is that clearer?

That said, for all you noncommercial operators, if you choose to ignore the ODP, be darn careful, because the existence of that ODP tells you there's something out there just waiting to reach out and touch you.
 
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This below seems to contradict that

Well, he did say applicable ODP. A clearance that includes a SID or a radar vector rules out an ODP but it's a moot point as they all take the obstacle into account.
 
I fly in the rockies where radar contact doesn't exist below 11K. I always fly the ODP, because I don't know if ATC has other aircraft in the area or waiting to come inbound. I have always assumed ATC will expect me to be on the ODP until I get into VFR or radar contact even though it isn't part of my clearance?
 
The OP said "chose to fly an ODP." Yes, for Part 91 it's your option. It's recomended in the AIM but not required by regulation unless 135, 121 and I'd say most military.

So like I said, if you chose to do it, stay on it as long as you want until you know you can proceed direct your first fix or ATC gets radar and send you direct your first fix.
 
I fly in the rockies where radar contact doesn't exist below 11K. I always fly the ODP, because I don't know if ATC has other aircraft in the area or waiting to come inbound. I have always assumed ATC will expect me to be on the ODP until I get into VFR or radar contact even though it isn't part of my clearance?

IME many controllers have little knowledge of ODPs. FAA Order JO 7110.65 tells controllers; "If a published IFR departure procedure is not included in an ATC clearance, compliance with such a procedure is the pilot’s prerogative." But I've found many controllers are not aware of that note and also unaware of ODPs at airports they serve.

Here is the ODP that applied to KMTW for many years:
DEPARTURE PROCEDURE: Rwy 7, climb to 2100 before turning south. Rwy 17, climb to 2100 before turning east.

KMTW was close to the Chicago ARTCC boundary so coordination was required before releasing a departure that would enter their airspace, the ZAU controller would provide a heading and altitude. After the call to ZAU the controller working KMTW would call the airplane and almost always the clearance would include, "upon entering controlled airspace fly heading...", followed by whatever heading ZAU had provided. No questions about departing runway, compliance with the local traffic pattern, terrain, or obstruction avoidance.

When I was the controller working KMTW the clearance would be, "leaving two thousand five hundred fly heading...", followed by whatever ZAU had provided. The MVA in that area is 2500 MSL.
 
IME many controllers have little knowledge of ODPs. FAA Order JO 7110.65 tells controllers; "If a published IFR departure procedure is not included in an ATC clearance, compliance with such a procedure is the pilot’s prerogative." But I've found many controllers are not aware of that note and also unaware of ODPs at airports they serve.

Here is the ODP that applied to KMTW for many years:


KMTW was close to the Chicago ARTCC boundary so coordination was required before releasing a departure that would enter their airspace, the ZAU controller would provide a heading and altitude. After the call to ZAU the controller working KMTW would call the airplane and almost always the clearance would include, "upon entering controlled airspace fly heading...", followed by whatever heading ZAU had provided. No questions about departing runway, compliance with the local traffic pattern, terrain, or obstruction avoidance.

When I was the controller working KMTW the clearance would be, "leaving two thousand five hundred fly heading...", followed by whatever ZAU had provided. The MVA in that area is 2500 MSL.

Thanks I learned something. Our other problem in the mountains is you cannot hear center frequency until you are ~2500-3000 AGL, so situational awareness isn't good. I guess we are relying on the "big sky" little airplane factor to some extent.
 
...almost always the clearance would include, "upon entering controlled airspace fly heading...",
Longtime pet peeve of mine. They ought to say, "When able, fly heading..." Pilots should be smart enough to know when they can and "entering controlled airspace" has nothing to do with it.

dtuuri
 
Thanks I learned something. Our other problem in the mountains is you cannot hear center frequency until you are ~2500-3000 AGL, so situational awareness isn't good. I guess we are relying on the "big sky" little airplane factor to some extent.

For separating aircraft operating IFR? Shouldn't be doing that in controlled airspace, and if you're operating at fields with instrument procedures there shouldn't be enough room to operate IFR solely within Class G airspace.
 
Longtime pet peeve of mine. They ought to say, "When able, fly heading..." Pilots should be smart enough to know when they can and "entering controlled airspace" has nothing to do with it.

dtuuri
The "entering controlled airspace" jargon is just a nod to the lack of jurisdiction ATC has in uncontrolled airspace.

Pilots should be smart enough to know they are allowed to follow an ODP until hitting rocks is no longer a factor.
 
I always fly the ODP, because I don't know if ATC has other aircraft in the area or waiting to come inbound. I have always assumed ATC will expect me to be on the ODP until I get into VFR or radar contact even though it isn't part of my clearance?
If the controller needs you to fly the ODP in order to provide separation with other IFR aircraft then he must include the ODP in your clearance. If neither a departure procedure or vectors are included in your clearance then whether or not to fly the ODP is up to you.
 
The "entering controlled airspace" jargon is just a nod to the lack of jurisdiction ATC has in uncontrolled airspace.

Pilots should be smart enough to know they are allowed to follow an ODP until hitting rocks is no longer a factor.

And controllers should be smart enough to know not to issue clearances that would preclude following an ODP.
 
I fly in the rockies where radar contact doesn't exist below 11K. I always fly the ODP, because I don't know if ATC has other aircraft in the area or waiting to come inbound. I have always assumed ATC will expect me to be on the ODP until I get into VFR or radar contact even though it isn't part of my clearance?

You are allowed to fly an ODP without a clearance for it unless you are assigned a SID (which includes obstruction avoidance).

Pilot/Controller Glossary
==============================
OBSTACLE DEPARTURE PROCEDURE (ODP)- A preplanned instrument flight rule (IFR) departure procedure printed for pilot use in textual or graphic form to provide obstruction clearance via the least onerous route from the terminal area to the appropriate en route structure. ODPs are recommended for obstruction clearance and may be flown without ATC clearance unless an alternate departure procedure (SID or radar vector) has been specifically assigned by ATC.
==============================
More detail available in AIM 5-2-8 and other FAA publications (not to mention a few NTSB accident reports!).

Whether ATC "expects it" or not depends. On the general theory that it's always a god idea for you and ATC to be on the same page, if the ODP was not part of my clearance, I will let ATC know I am on it when I first make contact in the air.
 
The "entering controlled airspace" jargon is just a nod to the lack of jurisdiction ATC has in uncontrolled airspace.
An unnecessary nod, though. As stated, it is a directive to turn as soon as you reach 700' AGL--very misleading and, judging by forum comments I've seen in the past, widely misunderstood.

Pilots should be smart enough to know they are allowed to follow an ODP until hitting rocks is no longer a factor.
I think some pilots feel the "directive" to turn "upon entering controlled airspace" preempts the need for following the ODP. A simple change in language would remove that.

dtuuri
 
For separating aircraft operating IFR? Shouldn't be doing that in controlled airspace, and if you're operating at fields with instrument procedures there shouldn't be enough room to operate IFR solely within Class G airspace.

I think his point was that there could be some VFR traffic in the area below where they get radar coverage/radio reception such that they have no radar assistance from ATC for separation, even though they departing aircraft is IFR. While ATC shouldn't be sending to IFR aircraft into that same space, there is no guarantee that VFR traffic won't be there. But I may be overlooking something.
 
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For separating aircraft operating IFR? Shouldn't be doing that in controlled airspace, and if you're operating at fields with instrument procedures there shouldn't be enough room to operate IFR solely within Class G airspace.

I am talking about Taos, NM (KSKX) 7093' MSL. The airport transition area is E above 700' AGL, the ODP takes you into class E space, but you are still below the MVA of 12,300 (from memory). Usually you fly to the nearest airway that is still 11K so you have a climb in E from 7-11K minimum with no radio and radar contact. Is this not an example of a pilot just having to take our chances with other aircraft and avoid obstacles until we can be seen?
 
An unnecessary nod, though. As stated, it is a directive to turn as soon as you reach 700' AGL--very misleading and, judging by forum comments I've seen in the past, widely misunderstood.


I think some pilots feel the "directive" to turn "upon entering controlled airspace" preempts the need for following the ODP. A simple change in language would remove that.

dtuuri
I think there are lots of rules and procedures that are "widely misunderstood." We can't fix all of them.

But yeah, I guess "when able" since the phrase is used anyway, added to "upon entering controlled airspace" as standard jargon wold be ok.

But don't for get to add it or "if able" to "turn left next taxiway," "cleared for the approach," "proceed on course," "descend and maintain" and all the other instructions pilots "widely misunderstand" to be ATC directives they must follow regardless of safety as well.

Or we can teach pilots that ATC folks are human beings who are not omniscient and make mistakes.
 
I think his point was that there could be some VFR traffic in the area below where they get radar coverage/radio reception such that they have no radar assistance from ATC for separation, even though they departing aircraft is IFR. While ATC shouldn't be sending to IFR aircraft into that same space, there is no guarantee that VFR traffic won't be there. But I may be overlooking something.

Yes exactly or there could be IFR aircraft in IMC at 12,300 MVA, perhaps circling over the valley waiting to fly an approach. I could just be circling up in the blind and come into radar contact near the other aircraft with no separation until ATC sees and identifies me.
 
I am talking about Taos, NM (KSKX) 7093' MSL. The airport transition area is E above 700' AGL, the ODP takes you into class E space, but you are still below the MVA of 12,300 (from memory). Usually you fly to the nearest airway that is still 11K so you have a climb in E from 7-11K minimum with no radio and radar contact. Is this not an example of a pilot just having to take our chances with other aircraft and avoid obstacles until we can be seen?
With other VFR aircraft yes. With theoretical other aircraft operating uncontrolled IFR below 700 AGL, yes. With obstacles if you choose not to follow an ODP, definitely.

But not with other IFR aircraft being handled by ATC. Your IFR clearance means there is a certain amount of airspace that is clear for you to operate. That's why you get a void time.

Am I misunderstanding your question?
 
With other VFR aircraft yes. With theoretical other aircraft operating uncontrolled IFR below 700 AGL, yes. With obstacles if you choose not to follow an ODP, definitely.

But not with other IFR aircraft being handled by ATC. Your IFR clearance means there is a certain amount of airspace that is clear for you to operate. That's why you get a void time.

Am I misunderstanding your question?

How much airspace it protected in the mountains? The approaches obviously and no one else will be given a departure clearance, but if I can fly anywhere I want in IMC until I come under positive control how can ATC make sure there is no one around me? For a specific example I am talking about Taos, NM KSKX (see my other post).
 
I think there are lots of rules and procedures that are "widely misunderstood." We can't fix all of them.

But yeah, I guess "when able" since the phrase is used anyway, added to "upon entering controlled airspace" as standard jargon wold be ok.

But don't for get to add it or "if able" to "turn left next taxiway," "cleared for the approach," "proceed on course," "descend and maintain" and all the other instructions pilots "widely misunderstand" to be ATC directives they must follow regardless of safety as well.

Or we can teach pilots that ATC folks are human beings who are not omniscient and make mistakes.

You're thinking like a lawyer not a pilot, i.e, you want to add more words and rules not less. Just drop the bit about controlled airspace--it's irrelevant.

dtuuri
 
I am talking about Taos, NM (KSKX) 7093' MSL. The airport transition area is E above 700' AGL, the ODP takes you into class E space, but you are still below the MVA of 12,300 (from memory). Usually you fly to the nearest airway that is still 11K so you have a climb in E from 7-11K minimum with no radio and radar contact. Is this not an example of a pilot just having to take our chances with other aircraft and avoid obstacles until we can be seen?

No, not if everyone is playing by the rules. The ODP assures obstacle avoidance, the clearance assures separation from other IFR aircraft. You won't get advisories on VFR aircraft until radio and radar contact with ATC but that's always the case, even in the flatlands.
 
Yes exactly or there could be IFR aircraft in IMC at 12,300 MVA, perhaps circling over the valley waiting to fly an approach. I could just be circling up in the blind and come into radar contact near the other aircraft with no separation until ATC sees and identifies me.

So your concerns are aircraft operating in IMC in controlled airspace without an IFR clearance?
 
No, not if everyone is playing by the rules. The ODP assures obstacle avoidance, the clearance assures separation from other IFR aircraft. You won't get advisories on VFR aircraft until radio and radar contact with ATC but that's always the case, even in the flatlands.



See post #28. If I choose not to fly the ODP, why wouldn't that scenario be a potential problem?
 
I think there are lots of rules and procedures that are "widely misunderstood." We can't fix all of them.

But yeah, I guess "when able" since the phrase is used anyway, added to "upon entering controlled airspace" as standard jargon wold be ok.

But don't for get to add it or "if able" to "turn left next taxiway," "cleared for the approach," "proceed on course," "descend and maintain" and all the other instructions pilots "widely misunderstand" to be ATC directives they must follow regardless of safety as well.

Or we can teach pilots that ATC folks are human beings who are not omniscient and make mistakes.

There are multiple issues at play for sure, however ambiguous instruction centered around irrelevant information is bad form in critical communications.

There is no need to mention Controlled Airspace at all, it has zero relevance to the operation. In a test question we would consider it a red herring and is a viable method of seeing if the test taker understands the subject by seeing if they factor it in. Well, the reality is that scores in the 70s and 80s on the written are a reality. When you combine that with the fact that ATC is not there to test pilots, rather to facilitate safe flight, in these regards, putting a Red Herring into an operational instruction is poorly though out. Adding a modifier to it to explain it is a Red Herring and irrelevant is a waste of time when the Red Herring can be directly replaced with the modifier and turn into one simple, relevant, instruction.

Remember, pilots aren't the brightest bunch, they'll fly a twin on one engine with their leg and not the trim holding the rudder against 260hp .because someone told them to. Keep It Simple.
 
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With other VFR aircraft yes. With theoretical other aircraft operating uncontrolled IFR below 700 AGL, yes. With obstacles if you choose not to follow an ODP, definitely.

But not with other IFR aircraft being handled by ATC. Your IFR clearance means there is a certain amount of airspace that is clear for you to operate. That's why you get a void time.

Pretty hard to do that without an IFR clearance. Can't fly enroute down there, it's below the 91.177 minimum altitude. Can't get in to the field without an IAP and they begin up in controlled airspace. You could depart in IMC and reach VMC before reaching controlled airspace, but you may have to stay in uncontrolled airspace. If you have clouds beneath, you won't have VFR minimum cloud clearance before reaching controlled airspace.
 
Yes exactly or there could be IFR aircraft in IMC at 12,300 MVA, perhaps circling over the valley waiting to fly an approach. I could just be circling up in the blind and come into radar contact near the other aircraft with no separation until ATC sees and identifies me.

You're departing IFR. Doesn't matter if you're on an ODP or doing your own thing until reaching the MIA. ATC will assign you an altitude that will ensure seperation with the aircraft overhead.
 
How much airspace it protected in the mountains? The approaches obviously and no one else will be given a departure clearance, but if I can fly anywhere I want in IMC until I come under positive control how can ATC make sure there is no one around me? For a specific example I am talking about Taos, NM KSKX (see my other post).

They can make sure there are no other IFR aircraft around you by not issuing a clearance that conflicts with yours. They can't do anything with regard to VFR aircraft or aircraft operating illegally in IMC. That's true outside the mountains as well.
 
See post #28. If I choose not to fly the ODP, why wouldn't that scenario be a potential problem?

If ATC needs to assign the ODP for separation they will do so. If you choose to violate your clearance there is definitely a problem. Don't do that.
 
You're departing IFR. Doesn't matter if you're on an ODP or doing your own thing until reaching the MIA. ATC will assign you an altitude that will ensure seperation with the aircraft overhead.

Sure. So until then ATC can't see you and thus provide separation for you or any other aircraft. That's my point you can pop up on the radar anywhere and only then can you be separated. Much different than the flatlands where you are still a primary target as soon as you leave the ground.
 
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