IFR Departure, “turn heading XYZ”

[Velocity173]

This is out of the controllers manual. The controller is expecting you to turn based on 400 ft above the DER and off the DER.

Now, worth getting “jumped on”? No. Unless you were climbing like a slug, an early turn wouldn’t even be noticeable on radar.

 

[dmspilot]

This is out of the controllers manual. The controller is expecting you to turn based on 400 ft above the DER and off the DER.

Now, worth getting “jumped on”? No. Unless you were climbing like a slug, an early turn wouldn’t even be noticeable on radar.

View attachment 87066

The "and off the DER" part is not supported by the quoted passage.

 

[midlifeflyer]

??? AIM 5-2-9 d.

d. ....When an instrument approach is initially developed for an airport, the need for DPs is assessed. The procedure designer conducts an obstacle analysis to support departure operations. If an aircraft may turn in any direction from a runway within the limits of the assessment area (see paragraph 5−2−9e3) and remain clear of obstacles, that runway passes what is called a diverse departure assessment and no ODP will be published....

You are correct. I think that's a bit of semantics. A diverse departure is definitely an "obstacle departure procedure." But it is not an "Obstacle Departure Procedure."

 

[Velocity173]

The "and off the DER" part is not supported by the quoted passage.

Well the ICA starts at the DER. So at the DER. My point being, not before.

 

[dmspilot]

Well the ICA starts at the DER. So at the DER. My point being, not before.

The ICA only exists below 400 feet.

 

[midlifeflyer]

Being 400 feet above the end of the runway elevation at midfield does meet both elevation requirements. Being at 400 feet in and of itself meets the 35 foot thing. But ‘midfield’ doesn’t meet what the whole thing starts out with


1. Unless specified otherwise, required obstacle
clearance for all departures, including diverse, is
based on the pilot crossing the departure end of the
runway at least 35 feet above the departure end of
runway elevation, climbing to 400 feet above the
departure end of runway elevation before making the
initial turn....

You can’t cross the DER if you never get there because you turned at midfield

Don't confuse my occupational disability to read things in more than one way with what I actually think

 

[luvflyin]

Don't confuse my occupational disability to read things in more than one way with what I actually think Keep in mind that ATL's tower is just about 400' tall. Turning at midfield could be nasty.

Yup. That reminds me of something that happened many moons ago. There was construction going on adjacent to RW15 at Burbank KBUR. It was close enough to the Runway that a portion of it was closed, South of 7/25, now 8/26. The Tower was on top of the Terminal then at the Southeast corner of the intersection. With the closure of the South end the DER became before the Tower. Departure minimums got raised a lot, 800/2 I think.

 

[Velocity173]

The ICA only exists below 400 feet.

I’m talking about the assessment for obstacles. The ICA starts at the DER at a 40:1 slope and generally goes out to 2 nm. As long as the pilot climbs at 200 ft starting at the DER, they can turn on course at 400 AGL. If the aircraft is before the DER and below 400 ft, there’s no guarantee obstacle clearance for an early turn.

 

[John Collins]

So exactly what regulation would one be in violation of if it is VMC, part 91 operation and one commences a turn before the end of the runway and visually avoids obstacles? I understand the use for IMC when visual means are not available to avoid obstacles. It is certainly expected by a tower controller, but that does not mean it is required by regulation. Prior to departing from KCRE North Myrtle beach on an IFR flight plan, I was cleared for takeoff, proceed on course. So when at a safe altitude, I turned on course. I was probably at 400 ft but got to the altitude before the departure end of the runway. I got chewed out by the tower controller. I called the tower after I landed to discuss the situation and the supervisor just laughed and knew who I was talking about.

AIM Section 5-2-9 e. 1. is describing TERPS criteria which is intended to provide obstacle avoidance protection to the pilot on takeoff when they can't be expected to be able to visually avoid obstacles. It is not a regulation, it is an explanation of the answer to the lead question: "What criteria is used to provide obstruction clearance during departure?" Not turning before the end of the runway and reaching 400 feet unless otherwise specified is certainly a safe practice when conditions warrant it, but I am not obligated to follow it as a part 91 operator on a beautiful VMC day.

 

[Let'sgoflying!]

When I have received a takeoff clearance with the words full length, it was clearance to use the displaced threshold to begin my ground roll, not in reference to the departure end of the runway.

That makes sense.
This one did not have a DT however.
Thanks.

 

[dmspilot]

I’m talking about the assessment for obstacles. The ICA starts at the DER at a 40:1 slope and generally goes out to 2 nm. As long as the pilot climbs at 200 ft starting at the DER, they can turn on course at 400 AGL. If the aircraft is before the DER and below 400 ft, there’s no guarantee obstacle clearance for an early turn.

That doesn't address the issue of, if you are above 400 feet, can you turn before the departure end of the runway?

You stated:
"The controller is expecting you to turn based on [both] 400 ft above the DER and off the DER" then cited a passage to support your statement, but the passage (and its references) do not support the idea that you can't turn before the DER if you are above 400 feet.

The ICA is irrelevant if you are above 400 feet. The purpose of the ICA is to allow you to climb to 400 feet.

If the aircraft is before the DER and below 400 ft, there’s no guarantee obstacle clearance for an early turn.

I'm not talking about being below 400 feet, I'm talking about being above 400 feet.

 

[Let'sgoflying!]

My guess is they have been burned by early turns more than once. What airport? Parallel or intersecting Runways???

I think you are right, it was a very long runway. I think I was at ECP. There was someone doing pattern work, maybe a Pilatus? Seemed odd.
Anyway, to ensure we used full length, I held it on the ground until the last possible moment (I think we were doing 200kts by then) and pulled up lol

 

[flyingron]

Define ‘obligation.’ The AIM certainly implies you shouldn’t be indiscriminately turning before the end of the Runway. 4-3-3 FIG 4-3-2 and FIG 4-3-3, example 4 of both, pages 4-3-4 and 4-3-5

First off, 4-3-3- doesn't say anything close to what you're saying. If you were to take that as gospel, then you wouldn't turn below the TPA. Tell me how compliance with a traffic pattern is required for VFR aircraft unless the tower tells you. Tell me how it applies to IFR aircraft at all.

 

[flyingron]

Again the passage in the ATC handbook tells ATC that you can't expect the pilot to turn early, not that the pilot can't. It gives a maximum expectation of the turn commencing within two miles.

 

[luvflyin]

First off, 4-3-3- doesn't say anything close to what you're saying. If you were to take that as gospel, then you wouldn't turn below the TPA. Tell me how compliance with a traffic pattern is required for VFR aircraft unless the tower tells you. Tell me how it applies to IFR aircraft at all.

Yeah, the AIM figures and explanations are about the VFR traffic pattern and the thread is about IFR departures. You had said words to the effect of if you can do it visually then it doesn't matter, turn when you want. If you can do it visually it may be because it's VFR out and there may VFR traffic. The point I was making is that Controllers do not expect 'surprise' early turns and pointed to those items in AIM. I said nothing about it being Gospel. I believe implies was the word used.

 

[midlifeflyer]

So exactly what regulation would one be in violation of if it is VMC, part 91 operation and one commences a turn before the end of the runway and visually avoids obstacles?

None I know of. Given the number of times I have been instructed to make an early turn, if there was such a reg and if it were not accompanied by "except as authorized by ATC", there would be a heck of a lot of violations for Premier1's "friend" to call in.

I suspect in @Arob16's case (and he didn't mention which airport and which runway), all that happened was, there was an expectation by ATC for a higher turn, so when he turned below 400 he got questioned. It happens.

 

[Velocity173]

I know what you're talking about.

You stated:
"The controller is expecting you to turn based on [both] 400 ft above the DER and off the DER" then cited a passage to support your statement, but the passage does not support your statement, nor do the references cited by the passage support the statement.

So I haven't seen any evidence that you must be both 400 feet and at or beyond the departure end of the runway before turning.

The ICA is irrelevant if you are above 400 feet. The purpose of the ICA is to allow you to climb to 400 feet.



We're not talking about being below 400 feet, we're talking about being above 400 feet.

I already clarified above “at or after.” The “200 ft / nm from the DER” from the .65 and “unless specified otherwise...” from 5-2-9 from the AIM support that statement. The ICA depiction supports that statement as well.

Now, if you’re saying an aircraft at 400 ft and turning before the DER is safe, I’d say based on the diverse areas (A & B) assessment, that would be true. I believe an extreme turn before the DRP (2,000 ft from approach end) of greater than 180 degrees might be outside of OCS tolerances and not comply with diverse departure criteria.

 

[Larry in TN]

So exactly what regulation would one be in violation of if it is VMC, part 91 operation and one commences a turn before the end of the runway and visually avoids obstacles?

None that I know of. The problem is that the expectation is that the turn will not start until the end of the runway and 400'. This would most likely create a problem at airports with operations on multiple runways. The AIM does address unexpected maneuvers in the traffic pattern at towered airports and it was the controller's surprise at the unexpected maneuver that generated the reaction from the controller.

 

[dtuuri]

So exactly what regulation would one be in violation of if it is VMC, part 91 operation and one commences a turn before the end of the runway and visually avoids obstacles?

If you're a grossed-out crop duster on the way to a bean field it's probably ok. But climbing like a rocket up through the bottom of the pattern seems like it would be covered under "careless and reckless".

 

[flyingron]

f. The problem is that the expectation is that the turn will not start until the end of the runway and 400'.

The problem is there is NO SUCH expectation. The pilot's expectation is that if the pilot makes the turn after the end of the runway and at least 400 feet, he won't hit anything. The controller's expectation is that the pilot might not execute the turn before then, and that if he was given an "immediate" turn in the clearance, that the expectation is he do so before 2 miles.

If the turn would bring a pilot across another flight path, the controller had better not issue that turn instruction. Nothing in the FAR, nothing in the AIM, nothing in the instrument procedures, nothing in the ATC handbook precludes that early turn.

 

[RussR]

TERPS, FAAO 8260.3D, Chapter 14 DOES protect for turns before the end of the runway, the DER, as long as you have reached 400 feet above DER elevation. The ICA itself may start at DER, but that does not mean that no protection is afforded before it.

If you climb to 400 above DER elevation before turning, then you are guaranteed 96 feet of obstacle clearance anywhere in what's labeled below as as Diverse A, for anywhere past the DRP. This is because the highest an obstacle can be and not penetrate the departure surface is 76% of the 400 feet gained in the climb, or 304 feet above DER elevation. The Departure Reference Point, DRP is 2000 feet down from the start of the runway. The DRP kind of assumes nobody's going to be 400 AGL before traveling just 2000 feet from the start of the takeoff roll.

Notice that obstacles are evaluated using the shortest distance to either the ICA OR the runway centerline. The obstacles are evaluated assuming the aircraft has reached 400 feet above DER elevation regardless of where they are along the runway or into the ICA.

So from a TERPS perspective, you do NOT need to cross the DER before turning in order to have obstacle protection, assuming of course that you continue climbing.



Now, there is a slight shortcoming in criteria here, because that does depend on you maintaining exactly on centerline during your climb to 400 above DER elevation. Theoretically, the departure evaluation would miss a 303 feet tall obstacle just off the side of the runway. But fortunately, there are other airport design criteria that should prevent that, and so realistically this shortcoming doesn't cause any problems, at least that I am aware of.

 

[aterpster]

??? AIM 5-2-9 d.

d. ....When an instrument approach is initially developed for an airport, the need for DPs is assessed. The procedure designer conducts an obstacle analysis to support departure operations. If an aircraft may turn in any direction from a runway within the limits of the assessment area (see paragraph 5−2−9e3) and remain clear of obstacles, that runway passes what is called a diverse departure assessment and no ODP will be published....

??? AIM 5-2-9 d.

They mean a published abbreviated or full-route ODP. Nonetheless, the assessment required for departures from an IFR airport from a TERPs standpoint is what determines diverse, abbreviated, or full route. In the case of a diverse departure, you must climb to 400 feet before turning on course. Isn't that a procedure?

 

[Arob16]

Thanks for all the replies, definitely good things to think about. I am pretty convinced I didn't break any regulation but 48 hours or so of pondering makes me realize I probably could have waited a bit longer to turn. There was some traffic pattern aircraft, although no immediate danger/conflict. For those wondering, here was the exact verbiage used by controller/pilot through the situation:

(pre-taxi)
Controller: N1234 cleared to XYZ airport via, on-departure turn heading 335 vectors to ABC departure... (rest of clearance)
Pilot: Reads back

(at hold short line)
Controller: N1234 turn left heading 335, runway 3 cleared for takeoff (I read this back)

I commence my takeoff roll, probably airborne about 800 feet down the runway, climb to about 200 feet and turn left heading 335 as I am about 6,000 feet down the 8,200-foot runway.

Controller: N1234 FLY RUNWAY HEADING, you are not supposed to make your turn yet. Please wait until past departure end of runway or about one-half mile past (I found this 2nd part to be a confusing control instruction, containing two options)
Pilot: Sorry, thought I was cleared heading 335 per clearance (Turning back to Runway Heading now). I didn't understand your last control instruction, I will wait until you call my turn
Controller: N1234 I will call your turn.

And the rest was uneventful. I filed a nasa report of course. Hope nothing else comes of it!

 

[RussR]

The controller told you to turn left heading 335, then told you you should have waited for him to call the turn? It can't be both, it's one or the other.

It does sound like you turned earlier than the controller expected and he probably didn't plan for that. But that doesn't make it incorrect.

 

[PaulS]

Thanks for all the replies, definitely good things to think about. I am pretty convinced I didn't break any regulation but 48 hours or so of pondering makes me realize I probably could have waited a bit longer to turn. There was some traffic pattern aircraft, although no immediate danger/conflict. For those wondering, here was the exact verbiage used by controller/pilot through the situation:

(pre-taxi)
Controller: N1234 cleared to XYZ airport via, on-departure turn heading 335 vectors to ABC departure... (rest of clearance)
Pilot: Reads back

(at hold short line)
Controller: N1234 turn left heading 335, runway 3 cleared for takeoff (I read this back)

I commence my takeoff roll, probably airborne about 800 feet down the runway, climb to about 200 feet and turn left heading 335 as I am about 6,000 feet down the 8,200-foot runway.

Controller: N1234 FLY RUNWAY HEADING, you are not supposed to make your turn yet. Please wait until past departure end of runway or about one-half mile past (I found this 2nd part to be a confusing control instruction, containing two options)
Pilot: Sorry, thought I was cleared heading 335 per clearance (Turning back to Runway Heading now). I didn't understand your last control instruction, I will wait until you call my turn
Controller: N1234 I will call your turn.

And the rest was uneventful. I filed a nasa report of course. Hope nothing else comes of it!

I wouldn't worry about getting dinged by the FAA, you did what the controller asked. I generally don't turn before the end of runway unless specifically asked to do so.

 

[dtuuri]

Controller: N1234 FLY RUNWAY HEADING, you are not supposed to make your turn yet. Please wait until past departure end of runway or about one-half mile past (I found this 2nd part to be a confusing control instruction, containing two options)
Pilot: Sorry, thought I was cleared heading 335 per clearance (Turning back to Runway Heading now). I didn't understand your last control instruction, I will wait until you call my turn

Nice come-back on your part. At many airports ATIS directs to maintain runway heading 'till the MM (used to, when there were MMs), about 1/2 mile beyond the end.

 

[luvflyin]

The controller told you to turn left heading 335, then told you you should have waited for him to call the turn? It can't be both, it's one or the other.

It does sound like you turned earlier than the controller expected and he probably didn't plan for that. But that doesn't make it incorrect.

Controller didn't say he'd call the turn. He said wait until past departure end of runway. The pilot responded with the call my turn thing. Controller then agreed to.

 

[Velocity173]

The controller sounds like they might be miss interpreting the primary method for radar contact on departure. That is to identify a departing aircraft within 1 mile of the departure end. While 99 % of departures are directly off the departure end, the book doesn’t necessarily say they must be aligned with the departure end of the runway. Just have to be within 1 mile the departure end.

Still, even if they couldn’t see you within 1 mile, seconday (ident) method would have been just as easy. Not something worth getting worked up over.

 

[Larry in TN]

This 'incident' was all about the controller's expectations. He was expecting you to fly runway heading until the DER and 400' as almost all IFR departures do. Considering all of the factors that have already been discussed, that is a reasonable expectation. Anytime you want to do something that wouldn't normally be expected by ATC, just ask first.

 

[flyingron]

It's not a reasonable expectation. There's nothing anywhere that indicates that the pilot is so constrained. He's told not to expect the pilot may not be able to turn earlier, but it doesn't mean he can't.

 

[Velocity173]

Obviously this isn’t a reasonable pilot expectation for the OP but I’d say based on the controller’s reply, it’s a reasonable controller expectation. I can understand where a controller would expect the aircraft to be at or above 400 ft DER before turning. Now turning before the departure end is subject to interpretation.

 

[flyingron]

Again, nothing there indicates anything about when the pilot turns other than it will be expected no LATER than 2 miles. The note explains how the obstacle clearance is determined but doesn't say anything about that being a requirement for departures when procedure-based obstacle clearance isn't required.

 

[dtuuri]

Again, nothing there indicates anything about when the pilot turns other than it will be expected no LATER than 2 miles.

No later than 2 miles when instructed to make an "immediate turn", agreed? Not for normal turns.

 

[GBSoren]

I just flew out of KC downtown this weekend, was departing 19 but destination was north, clearance was make an immediate right turn to 250 heading. I can't say for sure how high I was when I began my turn but I always wait until 300' before getting my flaps up and I never turn before that. First time I've had that in clearance, cloud bases were about 3500' so obstacle avoidance wasn't an issue.

 

[Sluggo63]

Just curious, what airport were you departing from?

 

[GBSoren]

Just curious, what airport were you departing from?

KMKC

 

[smv]

KMKC

This KMKC?

 

[GBSoren]

This KMKC?

View attachment 87142

Yep, but I was given an immediate right turn to 250 heading. I had a business jet behind me so I think they wanted me out of his way.

 

[smv]

Yep, but I was given an immediate right turn to 250 heading. I had a business jet behind me so I think they wanted me out of his way.

Did either you or any of the ATC you spoke to acknowledge that you would not execute the published ODP?

 

[aterpster]

I just flew out of KC downtown this weekend, was departing 19 but destination was north, clearance was make an immediate right turn to 250 heading. I can't say for sure how high I was when I began my turn but I always wait until 300' before getting my flaps up and I never turn before that. First time I've had that in clearance, cloud bases were about 3500' so obstacle avoidance wasn't an issue.

They've been told for years not to use "immediate" for a departure turn. I wouldn't argue with them, I would turn at 400 feet. Let ATC make a federal case out of it.

I am very familiar with that airport. There can't be a traffic factor departing 19.