ODP and "After takeoff turn on course"

rocketflyer84

rocketflyer84

Line Up and Wait
Joined
Dec 25, 2014
Messages
713
Display Name
Display name:
RocketFlyer84
You are cleared for takeoff by tower with the instruction "turn right on course." Airport is in mountainous terrain and has an ODP that says fly runway heading till 2000' AGL before any turns. Your flight plan has a VOR about 40 miles away as the first fix. Because of the mountains there's no radar coverage until up in the air quite a bit.

Do you:

A) Complete the ODP then hit "direct" on the GPS and fly direct to your first waypoint from the point of completing the ODP (now about 6 miles from the airport) or,

B) Complete the ODP and then make a right turn back to intercept the imaginary line between the airport and your first fix (as if it was an airway) and then proceed on course

In other words does your "course" start from the departure airport or at the point when you complete the ODP?
 
If the weather is IMC you are well advised to follow the ODP. It the tower issues a contrary instruction state,"Unable, I must fly the ODP." If the weather is VFR and the turn is for an established noise abatement program you have to make a judgment call as to whether to fly the noise abatement procedure then turn to join the ODP.
 
aterpster said:
If the weather is IMC you are well advised to follow the ODP. It the tower issues a contrary instruction state,"Unable, I must fly the ODP." If the weather is VFR and the turn is for an established noise abatement program you have to make a judgment call as to whether to fly the noise abatement procedure then turn to join the ODP.
Click to expand...
Thanks, I get that... the question though is really what does "turn on course" mean in the context of the first point on your flight plan being a fix far from the airport. Even if one didn't complete the ODP to the final alt one would still be a ways from the airport before turning since there are mountains next to the runway.

When that turn starts should it be direct to the first fix (from the point this turn starts) or back to intercept a course between the airport and that first fix?
 
I've flown out of a lot of towered airports under IFR and I've never heard an instruction as vague as "turn right on course" for a departing IFR aircraft. You're typically on a SID, an assigned heading or on the ODP. As such, I'm questioning the validity of the scenario as its posted.
 
His question isn't really that complicated. Forget about ATC for a second.

When you file, you are filing to your first fix from the departure point. We aren't talking about SIDs here, but just published procedures for terrain clearance. So he's asking after flying the departure procedure, does he seek to intercept the course between the airport and the first fix or can he establish a new offset course to the first fix from the end of the departure procedure and still be "on course" per his filed plan.
 
Bonchie said:
His question isn't really that complicated. Forget about ATC for a second.

When you file, you are filing to your first fix from the departure point. We aren't talking about SIDs here, but just published procedures for terrain clearance. So he's asking after flying the departure procedure, does he seek to intercept the course between the airport and the first fix or can he establish a new offset course to the first fix from the end of the departure procedure and still be "on course" per his filed plan.
Click to expand...
Yes exactly.

To address the earlier point I've gotten "turn on course" after takeoff from ATC at towered airports before (usually in low traffic areas) but it was always joining an airway that passed over the airport so it was obvious that I should turn to join a specific path. The last time it happened it was as described in the scenario. I turned direct to my first fix after completing the ODP and then onwards per my flight plan from there but after debriefing the flight starting thinking if this was correct or not, or if there even is a correct response to that instruction. I'm used to getting vectors or a much more specific instruction from ATC.
 
I'd join your original course unless told to proceed direct XYZ fix. You're not going to find a definition of proceed on course though. It could be the filed course or present course.

Personally don't care for "proceed on course" phraseology. I always used "when able proceed direct (XYZ)," or "resume own navigation direct (XYZ)." Or if it's an airway, "fly heading ***, intercept V***, resume own navigation."
 
On course means on the course centerline. So to turn on course you need to intercept the cleared course. If the route an airway or charted route, this is clear. If it is a random point to point RNAV route, the course is defined as the great circle route between the two points. In some cases, a direct-to the first fix on the route is not much different than the point to point route, in which case you don't join the route centerline until you get to the first fix, and I doubt ATC will complain. If there is a substantial difference, then you would program your GPS to activate the leg and join the route by flying an intercept to the leg.

It is always the prerogative of the pilot to fly the ODP prior to flying on course. If there is any confusion between what the controller cleared an aircraft to do and what is expected of the pilot, it is the pilot's responsibility to immediately get it clarified.
 
If it's IMC, I would query tower that I need to fly the ODP for terrain clearence. In VMC, I'd look to see if I can make a "right on course" and avoid the terrain. If I couldn't I'd query tower on the need to fly the ODP for climb performance.
 
In this instance it seems vague but I woukd agree with john. I have been given a vector on an ifr plan before, for traffic, and after that situation was clear told proceed on course.
I tried to go direct to next fix but cfii said they would expect us to go back to the original course, mageta line, VOR radial, etc and continue to fix. Not to go from new position direct to the fix.

If going from new position to fix direct I woukd expect to hear fly runway heading, proceed direct to fix.

That's my take anyway.
 
rocketflyer84 said:
You are cleared for takeoff by tower with the instruction "turn right on course." Airport is in mountainous terrain and has an ODP that says fly runway heading till 2000' AGL before any turns. Your flight plan has a VOR about 40 miles away as the first fix. Because of the mountains there's no radar coverage until up in the air quite a bit.

Do you:

A) Complete the ODP then hit "direct" on the GPS and fly direct to your first waypoint from the point of completing the ODP (now about 6 miles from the airport) or,

B) Complete the ODP and then make a right turn back to intercept the imaginary line between the airport and your first fix (as if it was an airway) and then proceed on course

In other words does your "course" start from the departure airport or at the point when you complete the ODP?
Click to expand...

Do A.
 
Two things:

1. When I'm in contact with ATC, I tell them what I am doing to avoid any misunderstanding.
2. The magenta line and the next waypoint are usually in the same general direction.

Put those two together and I turn in the direction that makes the most sense to me. When I report in to ATC, I tell them where I am going so I can be corrected.

To answer the "mountainous terrain" OP I need more information - the situational awareness that leads to my best choice. I don;t have an answer without it.
 
Don has a good point in the article but it still doesn't clarify the ambiguity of "proceed on course." What the controller might assume isn't always what the pilot assumes. Generally it's not an issue because the distance between present course and filed course probably won't be a change in MIA and won't be a separation factor.

Easiest and most clear instruction is to say "turn right, proceed direct..."
 
This thread brings back memories of the August, 1996 tragic USAF C-130 departure CFIT at KJAC. They were simply cleared direct to the first VOR on their high-altitude routing. They didn't know anything about ODPs (IFR departure procedures in those days) so gear up, en route climb configuration and they turned left direct to that VOR. Sadly, a mountain got in the way. Nine died.
 
roncachamp said:
Do A.
Click to expand...


Agree. Unless the clearance involves an airway to that first fix, what does it matter if the magenta line is from the actual field or end of the ODP to that first fix in a /G environment? (well, except not hitting the mountain of course but we are talking about defining the "course")
 
The times when I've been told by a tower controller to proceed on course, I was VFR, so I assumed that it was roughly equivalent to "resume own navigation."
 
Velocity173 said:
Don has a good point in the article but it still doesn't clarify the ambiguity of "proceed on course." What the controller might assume isn't always what the pilot assumes. Generally it's not an issue because the distance between present course and filed course probably won't be a change in MIA and won't be a separation factor.

Easiest and most clear instruction is to say "turn right, proceed direct..."
Click to expand...

The ambiguity is a little unnerving when you're so used to more specific instructions. We get this kind of thing down in the Caribbean a lot. We'll be on a tower assigned heading after takeoff, and departure will tell us to "turn left proceed on course" - our course being an airway that's over 90 degrees to our left. I've queried departure about it before, and they just said, "however you want to join Gxxx is up to you". So we pick a heading with a reasonable intercept angle and off we go. I've tried to find some actual guidance on this, but can't seem to find anything relevant.
 
kayoh190 said:
The ambiguity is a little unnerving when you're so used to more specific instructions. We get this kind of thing down in the Caribbean a lot. We'll be on a tower assigned heading after takeoff, and departure will tell us to "turn left proceed on course" - our course being an airway that's over 90 degrees to our left. I've queried departure about it before, and they just said, "however you want to join Gxxx is up to you". So we pick a heading with a reasonable intercept angle and off we go. I've tried to find some actual guidance on this, but can't seem to find anything relevant.
Click to expand...

Give me the ICAO identifier of an airport where this has happened so I can look at the official departure procedure(s), if any.

In the U.S., if an IFR airport has IFR takeoff minimums, but no departure text, then from an obstacle standpoint once leaving 400 feet you are free to turn on course. A 40:1 clear departure surface is presumed out to 25 miles in non-mountainous areas; 46 miles in designated mountainous areas. (AIM 5-2-8)
 
aterpster said:
If the weather is IMC you are well advised to follow the ODP. It the tower issues a contrary instruction state,"Unable, I must fly the ODP." If the weather is VFR and the turn is for an established noise abatement program you have to make a judgment call as to whether to fly the noise abatement procedure then turn to join the ODP.
Click to expand...

The ATC order 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."
 
roncachamp said:
The ATC order 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."
Click to expand...
That has been the case as far back as I can remember. But, that is from an ATC perspective. 91.175 was changed several years ago to make ODPs mandatory for Part 121 and 135 unless those operators have an FAA approved company procedure.
 
I think the word "course" is the problem. In this context I take it to mean "the rest of the clearance." That may or may not involve grtting on some centerlines.


c. Departure Procedures.

1. Specify direction of takeoff/turn or initial

heading/azimuth to be flown after takeoff as follows:

(a) Locations with Airport Traffic Control

Service− Specify these items as necessary.

(b) Locations without Airport Traffic Control

Service, but within a Class E surface area− specify

these items if necessary. Obtain/solicit the pilot’s

concurrence concerning these items before issuing

them in a clearance.

NOTE−

Direction of takeoff and turn after takeoff can be

obtained/solicited directly from the pilot, or relayed by an

FSS, dispatcher, etc., as obtained/solicited from the pilot.

(c) At all other airports− Do not specify

direction of takeoff/turn after takeoff. If necessary to

specify an initial heading/azimuth to be flown after

takeoff, issue the initial heading/azimuth so as to

apply only within controlled airspace.

2. Where an obstacle departure procedure

(ODP) has been published for a location and pilot

compliance is necessary to ensure separation, include

the procedure as part of the ATC clearance.

EXAMPLE−

“Depart via the (airport name)(runway number) departure

procedure.”

Or

“Depart via the (graphic ODP name) obstacle departure

procedure.”

NOTE−

Some aircraft are required by 14 CFR 91.175 to depart a

runway under IFR using the ODP absent other instructions

from ATC.

NOTE−

IFR takeoff minimums and obstacle departure procedures

are prescribed for specific airports/runways and published

in either a textual, or graphic form with the label

(OBSTACLE) in the procedure title, and documented on an

appropriate FAA Form 8260. To alert pilots of their

existence, instrument approach procedure charts are

annotated with a symbol:

3. Do not solicit use of the Visual Climb over

Airport (VCOA) option.

NOTE−

Pilots will specifically advise ATC of their intent to use the

VCOA option.

4. Compatibility with a procedure issued may

be verified by asking the pilot if items obtained/

solicited will allow him/her to comply with local

traffic pattern, terrain, or obstruction avoidance.

PHRASEOLOGY−

FLY RUNWAY HEADING.

DEPART (direction or runway).

TURN LEFT/RIGHT.

WHEN ENTERING CONTROLLED AIRSPACE

(instruction), FLY HEADING (degrees) UNTIL

REACHING (altitude, point, or fix) BEFORE

PROCEEDING ON COURSE.

FLY A (degree) BEARING/AZIMUTH FROM/TO (fix)

UNTIL (time),

or

UNTIL REACHING (fix or altitude),

and if required,

BEFORE PROCEEDING ON COURSE.

EXAMPLE−

“Verify right turn after departure will allow compliance

with local traffic pattern,”or “Verify this clearance will

allow compliance with terrain or obstruction avoidance.”

NOTE−

If a published IFR departure procedure is not included in

an ATC clearance, compliance with such a procedure is the

pilot’s prerogative.
 
rocketflyer84 said:
Thanks, I get that... the question though is really what does "turn on course" mean in the context of the first point on your flight plan being a fix far from the airport. Even if one didn't complete the ODP to the final alt one would still be a ways from the airport before turning since there are mountains next to the runway.

When that turn starts should it be direct to the first fix (from the point this turn starts) or back to intercept a course between the airport and that first fix?
Click to expand...

Direct to the first fix on your assigned route, which I assume would require a right turn based on the instruction "turn right on course" issued by the tower.
 
aterpster said:
Give me the ICAO identifier of an airport where this has happened so I can look at the official departure procedure(s), if any.
Click to expand...

I was specifically thinking of MBPV. There are a couple of DPs for the airport, but we never get them. Departing east, we'll be on a heading (runway heading, usually) from tower, then departure will keep us on that heading for about another 10 miles. Eventually we'll be told to turn left and proceed on course. Our routing is PVN.G629.LYMIN.G446...

If this were the US, I'd be given a heading and told to join G629 from that heading, or just given direct to a fix along the airway. But when not given a specific way to join, what's the 'proper' way to do it? PVN is the first fix of my route and that seems like it'd be the book answer, but I don't think making a 180 back to the airport is what Provo wants me to do. They seem to just want me to point the plane in the general direction of G629 and join up. Like I said, we've asked, and they just don't care. There's no terrain for me to hit, so I'm not terribly concerned either, but I've always been curious what the right answer was. Perhaps the controller is in the wrong by not being more specific, but I tend to assume that it's *me* being the dumbass when there's any doubt. ;)
 
aterpster said:
That has been the case as far back as I can remember. But, that is from an ATC perspective. 91.175 was changed several years ago to make ODPs mandatory for Part 121 and 135 unless those operators have an FAA approved company procedure.
Click to expand...

Making ODPs mandatory for some operators did not create a conflict with that ATC perspective. So that ATC and pilots would have the same perspective on things like this the FAA created the Pilot/Controller Glossary, which has this to say about ODPs:

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.
Click to expand...

SIDs provide obstacle clearance so are not an issue. If cleared via radar vectors and assigned a departure heading that appears to conflict with an ODP, query the tower controller.
 
Last edited:
kayoh190 said:
I was specifically thinking of MBPV. There are a couple of DPs for the airport, but we never get them. Departing east, we'll be on a heading (runway heading, usually) from tower, then departure will keep us on that heading for about another 10 miles. Eventually we'll be told to turn left and proceed on course. Our routing is PVN.G629.LYMIN.G446...

If this were the US, I'd be given a heading and told to join G629 from that heading, or just given direct to a fix along the airway. But when not given a specific way to join, what's the 'proper' way to do it? PVN is the first fix of my route and that seems like it'd be the book answer, but I don't think making a 180 back to the airport is what Provo wants me to do. They seem to just want me to point the plane in the general direction of G629 and join up. Like I said, we've asked, and they just don't care. There's no terrain for me to hit, so I'm not terribly concerned either, but I've always been curious what the right answer was. Perhaps the controller is in the wrong by not being more specific, but I tend to assume that it's *me* being the dumbass when there's any doubt. ;)
Click to expand...
I'd turn north and join G629 on a 30 degree angle of intercept, or so. In the other instance a heading assignment seems odd since they don't seem to have radar. The moral of the story is be familiar with the terrain because at some other location that could be an issue. These ambiguous clearances also occur in South America, although less so than the years before they went to decent SIDs. Nice thing about skyvector.com you can look at the WACs for much of the Caribbean. The 121 operators have to have OEI procedures, so they have access to the best topographical data that sometimes can only be obtained with the help of the countries government aviation authority. APG has good terrain data, but they don't share other than to provide OEI procedures to their subscribers. The technology offered today is awesome, such as S.V. and TAWS. Great for "last resort" terrain avoidance, but not much good for manmade structures in much of the world.
 
aterpster said:
I'd turn north and join G629 on a 30 degree angle of intercept, or so. In the other instance a heading assignment seems odd since they don't seem to have radar. The moral of the story is be familiar with the terrain because at some other location that could be an issue.
Click to expand...

That's exactly what I do. And yep, if terrain were around it could be a much bigger issue. I'm 121 at a large carrier, so like you said - if terrain is an issue we have procedures for just about any situation.
 
I got that yesterday (IFR filed in VMC) out of Boston in a C172: "fly heading 020, clear for takeoff." I assumed they'd want me off runway heading pretty quickly so the big kids could get past me. Nopers, they were expecting all the way to the end of the runway (two miles long!) before turn out, even at my 80-knot climb speed. Didn't help that the SID was "non-turbine aircraft expect radar vectors to first fix, and filed altitude 10 minutes after departure."

So, I would fly the ODP as published before turning.

R
 
I do option A. Just remember you are still responsible for terrain clearance. So make sure doing so will keep you clear of obstacles.
 
Why not just clarify before you turn?
If you're in VMC who cares? But a good question if in IMC.
 
coma24 said:
I've flown out of a lot of towered airports under IFR and I've never heard an instruction as vague as "turn right on course" for a departing IFR aircraft. You're typically on a SID, an assigned heading or on the ODP. As such, I'm questioning the validity of the scenario as its posted.
Click to expand...
I have. It usually happens when you get "cleared as filed" in your clearance, and your first point is a VOR or waypoint somewhere down the road. I can't recall ever having gotten it when there was an ODP, though.

In any case, I don't interpret "cleared on course" to mean intercepting the course from the airport to the first waypoint. I would go direct to the first waypoint after entering the turn.
 
aterpster said:
This thread brings back memories of the August, 1996 tragic USAF C-130 departure CFIT at KJAC. They were simply cleared direct to the first VOR on their high-altitude routing. They didn't know anything about ODPs (IFR departure procedures in those days) so gear up, en route climb configuration and they turned left direct to that VOR. Sadly, a mountain got in the way. Nine died.
Click to expand...

As I recall there was no "direct" in the clearance they got. It was the VOR then as filed. I was looking for the transcripts but couldn't find them. Are they still around somewhere?
 
Everskyward said:
I have. It usually happens when you get "cleared as filed" in your clearance, and your first point is a VOR or waypoint somewhere down the road. I can't recall ever having gotten it when there was an ODP, though.

In any case, I don't interpret "cleared on course" to mean intercepting the course from the airport to the first waypoint. I would go direct to the first waypoint after entering the turn.
Click to expand...
This is what I do as well.
 
Everskyward said:
In any case, I don't interpret "cleared on course" to mean intercepting the course from the airport to the first waypoint. I would go direct to the first waypoint after entering the turn.
Click to expand...

For the sake of argument, what if the first waypoint was a VOR on the airport you departed from, then an airway to your next fix?
 
kayoh190 said:
For the sake of argument, what if the first waypoint was a VOR on the airport you departed from, then an airway to your next fix?
Click to expand...
I've always just intercepted the airway. If you went direct to the next fix, then you wouldn't be on VXXX anymore.
 
kayoh190 said:
For the sake of argument, what if the first waypoint was a VOR on the airport you departed from, then an airway to your next fix?
Click to expand...
It would just be for the sake of argument since I don't file like that off an airport, and we file our own flight plans. But, I guess if I filed an airway I would ask for clarification given "climb on course". But in that case, I would expect to be given either a heading to join or direct the next waypoint.
 
kayoh190 said:
For the sake of argument, what if the first waypoint was a VOR on the airport you departed from, then an airway to your next fix?
Click to expand...
That's the problem with answering based on a vacuum. It's easy to find a "real" situation in which the vacuum answer doesn't work.
 
midlifeflyer said:
That's the problem with answering based on a vacuum. It's easy to find a "real" situation in which the vacuum answer doesn't work.
Click to expand...

Yeah, I'm definitely not trying to sharpshoot anyone - I was just curious how people would handle it. It goes back to my little Caribbean situation I posted about earlier. I think I'd always expect a heading to join or direct to a fix, and ask for clarification if I didn't get it.
 
kayoh190 said:
For the sake of argument, what if the first waypoint was a VOR on the airport you departed from, then an airway to your next fix?
Click to expand...

In a situation where an ODP took me some distance away from the airport I wouldn't file an on-airport VOR as the first fix.
 
roncachamp said:
In a situation where an ODP took me some distance away from the airport I wouldn't file an on-airport VOR as the first fix.
Click to expand...

I wouldn't ordinarily file that way either, but I'll get that at work on occasion. But other than a couple places outside the US, I've never had a controller clear me on course without a heading or direct to a fix first. It was more a curiosity thing for me.
 
You must log in or register to reply here.
Back
Top