Obstacle Departure Procedures
 

I have been taught that we are not supposed to follow an Obstacle Departure Procedure unless the tower is closed. Has anybody else heard this before?

I found this in the AIM 5-2-8 "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."

If a heading is assigned during the take off clearance is that a radar vector? What if the tower does not have radar?
What if the t/o clearance is turn left on course?
What if the ODP just says no turn before a certain altitude and you get a radar vector? Do you turn at 400agl or at the ODP altitude?
What if it says left turn fly this heading until 2400ft and the assigned heading is a greater left turn? Does this mean it is a radar vector and it is specifically assigned by ATC and I am not allowed to fly the ODP?

Sorry in advance for so many questions in one post.

Yes radar vector, because they are coordinating with ATC

If a departure procedure was given to you in your clearance-Comply with it

If a departure clearance was given to you in your clearance but before takeoff they give you assigned heading-Fly heading whenever your accel alt or what company has elected as safe alt to turn, prob 400ft agl

Tower is closed and your getting your clearnace on ground and youve been released and the weather isnt good to where you cant maintain visual of obstacles-Fly the departure

Tower is closed and your getting your clearnace on ground and youve been released and the weather is good to where you CAN maintain visual of obstacles-Accept a heading, and they will state maintain visual of obstacles

ODP usually just for weather purposes, cant maintain visual contact

Depends what plane your can do, if your plane cant clear the obstacles the ODP is necessary.

I believe if you want to fly an ODP that is not associated with a regular Departure procedure or SID(i.e. just one written on the bottom of the airport diagram on the Jepp charts) you have to tell ATC that you are going to fly it. It is not something assigned by ATC

In what situations am I not allowed to do the ODP is the better question?

Section 5-2-8 of the AIM basically tells me that even if the ODP says RWY HDG until 2500MSL (lets just say that is = 1000AGL) but ATC gives me a heading with the t/o clearance I don't wait until 2500. I turn at the minimum which is 400agl (also in 5-2-8). Assuming we agree that a heading assigned on t/o is a radar vector.

I should also say I am asking and replying in regards to aircraft under an IFR flight plan.

Generally speaking, under part 91, published ODP's are optional, ATC assigned departures (including headings) aren't. But under 121 or 135 there may be company policies that come into play. My previous company had guidance in their FOM for IFR departures that were generally more restrictive than the FAR/AIM - basically, if we weren't assigned a named SID or given a departure heading (like from an uncontrolled field) then we had to fly the ODP regardless of the current wx conditions.

What he said.

Your companies FOM most likely has guidance on what you are supposed to do.

Something like this:
If IMC or unable to maintain visual terrain clearance and no other ATC departure instruction received, the ODP must be flown. (ATC is taking responsibility for terrain clearance when issuing the vector)

VMC and able to maintain terrain clearance visually it is optional unless company specifically requires it for that airport.

Its my understanding after looking into this question years ago, that if an ODP is published for that runway, you climb until reaching that published altitude before making a turn issued by tower. The reason being is that tower does not have "radar contact" on you yet. Until you are given over to an approach/departure controller who says "radar contact," or after reaching the published ODP altitude, only then can you turn to the assigned heading given by ATC. This is a very good question and I could potentially be wrong, but hopefully someone on here has a definitive answer for us.

Like others have said, the company procedures are probably best to follow if you got them...I will add this also

I have heard guys getting calls from the FAA about not leaving the pattern correctly when in this example Tower was closed...just departing (VFR with a IFR Clearance from APP or CTR above) and at my company (121) at 400AGL you can turn on course ...Our FOM says if we can maintain our own terrain clearance it is pilots discretion on whether or not we follow it based off what people have mentioned already. However we always tell ATC if we can maintain our own terrain clearance in the climb just to make sure there is no confusion on what ATC expects us to do.

So even with nobody in the pattern someone on the ground called and complained because a pilot decided to turn right at 400ft and not do the traffic pattern, the FAA did not like that.

Deciding whether or not to follow it isn't really cut and dry like we all hope it is...There are many factors that come into play and its almost a case by case scenario for this one. Also people are quoting stuff they are reading in the AIM...remember that is for guidance only, its not a reg...yes the FAA can still get mad at you for doing something different then what is in there but still not a violation....

Hope this helps!

The only thing i can think of in terms of people calling on the ground is due to a noise abatement procedure that probably wasn't followed...ODP's are flown in lieu of other clearance and departing VFR, or you can reference your company's 10-10 pages which more than likely spell out what to do..ODP, in my opinion, is the last thing flown and referenced only when the tower is closed and you need some form of guidance in the transition from vfr-ifr....

Fly the ODP unless tower gives you a different clearance. We had a crew get in trouble in TYS, a while back. Taking off 5R the ODP says something like "no turns east before 4000'. Tower told the guys "turn right 090 after departure, cleared for takeoff". They should have turned at 400' but didn't until 4000' and got in trouble. If you want to do the ODP instead of tower clearance you have to let the tower know so they can clear you for that procedure. Great question for discussion!

I believe that 91.175 governs this, could be wrong on the reg. You will fly the ODP unless you have an alternate procedure (a SID, vectors, etc). Its no longer optional for 121 or 135 on an IFR flight plan. And as another person posted, make sure to rectify a clearance that takes you out of compliance with an ODP if you aren't on a SID. I've been told to fly straight into a mountain after takeoff, instead of doing the ODP.

I have a question also....

You're at a non-towered airport, weather is low,and you can't meet the climb gradient of the ODP. (but do meet standard IFR climb gradients 3.3%) You also do not have the weather in the "OTHER" section and changing runways is not an option. Are you still legal to t/o seeing how ODP's are optional? This is for a part 135/121 trip.

If you're not compliant with an ODP's climb gradient I would think it's illegal to use the procedure. But in leiu of the procedure is there any other way to depart legally? I would think not because then you have no real obstacle clearance guidance in the case of single engine. This is also assuming your not in contact with center yet to receive a vector. And even if you did receive a vector, if you lost an engine you may hit the mountain side well before reaching the 400' before making your turn.

We have a few airports that have gradually rising terrain for a few miles before the sudden mountain shoots up. Our planes, single engine, would barely be able to climb over the gradual terrain let alone the mountain. And we certainly would hit the mountain before reaching a safe turning altitude to avoid the shallower terrain..


In my mind I wouldn't do it, but is it legal?

I was under the impression an ODP is issued when the standard climb gradient/procedure doesn't meet the required terrain clearance, hence the turn and higher required climb gradient to meet the required terrain clearance.

So i'd say no. You would have to reduce the planes weight to meet the climb requirements.

That said both 121 companies I worked for had runway analysis (which would limit a/c weight to ensure the appropriate climb gradients/terrain clearance were met for each specific runway) and if terrain clearance was an issue a "special engine out procedure (which was runway specific) used to meet required terrain clearance.

These are my understanding as well but I could be wrong. I have no idea where I'm getting it from but I remember hearing multiple times from multiple people that under 121 you are required to do the ODP unless cleared otherwise. I always ask for a VFR climb on course if the weather is good and center will ask if I can maintain terrain/obstruction clearance through xxx altitude. I say I can and they give me the VFR climb on course.

ODP's are generally issued when TERPS criteria cannot be met. Like most mountaneous airports. But even then there are still some instances where a minimum climb gradient exhists for an ODP. That's the exact reason I was asking. We can meet standard IFR cl. req. But cannot meet the ODP %. I agree that the only way to meet it would be to reduce weight.

We had runway analysis at one of my former airlines also. Made it much easier. Unfortunately, in my current gig we on our own. If we told a dispatcher we couldn't go because of a ODP climb gradient we'd get the "deer in the headlights" look. They simply don't know this stuff.

So I think the answer is it would be illegal to depart on a pt. 135 trip not being able to meet the ODP gradient % (even if you could meet standard IFR 3.3%)....Especially since we can't just depart into low ceilings and vis, and make a turn seeing how we still have some rising terrain preceeding the mountain obstacle.

That is correct. It comes from OpSpec C077.

If I remember correctly, an ODP is optional, either in VFR or IFR conditions, and was created for the second condition when climb gradient could not be achieved.

A SID on the other hand, requires an ATC clearance, in either VFR or IFR conditions.

I could be mistaken though....

An ODP in not optional for 121 or 135. You must follow the ODP when not given specific intructions in your clearance (SID or heading).

I was referring to Part 91 though, and should have made that clear in my earlier post.

I like to think of it as this. Do what tower tells you, whether it be a SID or a vector. If they don't tell you how to transition (the tower is closed) fly the obstacle departure. If none exists for that RWY turn at 400'.

I do it whether it's IFR or VFR for practice.

I would add that even if tower gives you a turn (or center if you are able to get in contact before t/o) be very carefull. They don't know the single engine performance of your aircraft. If they issue a turn but there also is an ODP for that runway (and assuming you meet the climb gradient) it would be perfectly fine for you to tell them you'd like to do the ODP. Probably a very rare occurance since if there's mountaneous terrain there is most likely a departure procedure or ODP that is standard issue.

(we've had center issue turns that would have put a/c into the sides of mountains, two engines or not)

If no ODP exhists then all you have to meet is standard IFR climb gradients and turning at 400' won't be a problem.

Look at this, a quality dialogue of information. These message boards may have use after all!!:D

Reading this thread makes one fear for the quality of IFR training in the US. This is very basic stuff.

IF you don't follow the ODP or cannot maintain the published gradient, how do you propose to avoid hitting the terrain in IMC? It is mandatory for commercial operators, but the terrain and the plane couldn't care less about who's paying and who's is not.

The FAA just sent this Safety Notice:

If you do NOT follow the ODP, how would any of you propose to avoid hitting the terrain when in IMC?

The climb gradient in the Take-Off Minimums page (NACO) or on the Airport page (10-9 Jepps) is derived from the airfield survey that is part of making any airport "IFR". The TERPS specialist uses a Obstacle Identification Surface, which rises at 152 ft/nm from 35 feet above the Departure End of Runway (DER). If there are NO penetrations, the specialist adds a "fudge factor", defined in TERPS, of 48 ft/nm and it is done. That's where the 200 ft/nm (3.3%) comes from. Without penetrations, a "diverse departure" (FAA TERPS) or "omnidirectional departure" (ICAO PANS-OPS Doc 8168 Vol. II) is authorized--climb runway heading to 400 feet above DER elevation and turn on course.

IF there are penetrations, the TERPS specialist identifies a gradient that will clear the obstacle, adds 48 ft/nm and rounds up to the next 10 ft/nm. Done, unless the terrain requires a prohibitively high gradient, then a route, route and gradient >200 ft/nm, or a ceiling and visibility may be specified It could be simple "maintain runway heading to 1400 feet" or complex like Aspen (KASE).

"Runway Heading" is NOT a vector, it is an ATC instruction and does not necessarily imply terrain clearance. One is on a vector when, and only when, a heading and altitude is specified. "Radar Contact" only means he has you identified on radar, nothing more or less.

SIDs Vs. ODPs? A SID is designed for ATC, it routes you where they want/need you to go, mostly for airspace reasons. ODP is a TERPS requirement to keep airplanes away from rocks, period. If it can't be done by the TERPS specialist, how much better are we pilots?

Understanding this area should be basic to instrument flying and there should be no confusion. It is the reverse of flying the IAP to land

GF

Whether it's a vector or an instruction, failure to comply could put one in jeopardy of violating § 91.123.
That notice the FAA just sent out seems to conflict with this section of the AIM.
Maybe this is a big problem in certain parts of the country. In my experience though, I can't ever recall departing an airport with a DP and an operational tower without receiving explict departure instructions from ATC.

Based on all the conflicting information, and on the off chance that one is issued "Cleared as Filed" and no intial vector or assigned DP, it's probably best to clarify with that controller who exactly will be providing terrain/obstacle clearance. If you are, then specify that you will be flying the DP. If he is, then do a reality check and refuse the clearance if necessary.

So OP, follow the controller's instructions unless to do so would put your aircraft at risk. Notify him if you are unable to comply and clarify what your intentions are. Don't just randomly fly a DP at an operational, controlled field without clearance or at least some warning. That's my advice.

SR22

You have to be in radar contact, in controlled airspace, to be vectored, hence it is not a vector until identified. There are .65 (ATC Manual) rules for vectoring below the MVA, but in general you must be above the minimum vectoring altitude. It is an instruction, and yes once acknowledged must be followed unless an emergency exists.

The FAA Notice is directed at uncontrolled or non-radar operations where ATC might not be able to assign a departure. ATCOs are advised in FAAO 7110.65 that it is the pilot's prerogative to fly an ODP.

What I am noting here is that few pilots have been trained and operating non-radar or uncontrolled IFR. It is a different world and a number of them have come to grief not knowing how. I recently landed in uncontrolled airspace at an uncontrolled airport with us and two airliners holding "legs and direction at pilot's discretion, cruise FL 160"

GF

Even at an uncontrolled, non-radar field I'm gonna let the FSS guy know to let the ATC guy know that I'm gonna be flying the DP to join, assuming the clearance didn't provide me with specific departure instructions to the contrary. That way when I pop-up heading east instead of west, he's not surprised and I don't run into anyone.

With so many controllers retiring and so many noobs directing traffic, maybe the guy issuing the clearance missed the fine print at the very bottom of chapter 4, section 3 after all that other stuff about how he's supposed to assign DPs. Or maybe he's expecting the pilot to convey whether he will choose to exercise his prerogative. While one MAY not be violated for disregarding ATC instructions in the aforementioned situation, it just seems like the smarter play to communicate one's actual intentions.

Like you said, definitely fly it if you have no other way to avoid terrain. Just make sure the guy who's keeping you from a mid-air knows you will be. Don't accept one clearance, only to do something different once in the air. You agree, Cap?

I don't disagree, letting the controller in on your plan is very definitely recommended.

From some of the posts here, there seemed to be confusion about ODPs and procedural control. Pilots get very used to be coddled by FAA radar control and rules, then fly in non-radar or overseas and we Cali, Columbia accidents because they don't understand the environment.

GF

I'm an FAA TERPSTER and a pilot. Has this issue been cleared up or are there more questions on the issue?

Follow the ODP when departing into IFR conditions unless you are assigned a SID or another ATC assigned route.

If you do not follow the ODP, you are putting yourself/passengers at risk.

Climb gradients exist because there is a hazardous obstacle (or terrain) identified in the departure area. If you cannot meet the CG or the required visibility and ceiling, do not depart under any circumstance.

If there are more questions on the subject (or any TERPS subject) I would love to help.

Most of that was correct although the criteria has changed quite a bit on departures (see 8260.46D). Kudos to your knowledge on aviation! It's quite a breath of fresh air to see that users of our product (or Jepp which uses our data and calculations) knows what all is going into the design of procedures.

Clipperstall

Thanks for the FAAO on DPs. It has been a while since USAF Instrument Instructor School. Yes, many details have changed, some potentially serious, but the basics that pilot should be aware of haven't. The 24% rule was a big change, but mostly for us tech geeks--the concept is similar. What I haven't gotten a fundamental feel for is RNP and RNP AR approaches. I was VFR into KASE in a Global Express last summer out of curiosity I loaded a RNP approach contained in the DB. Yes, we and the plane are not approved, but the Honeywell database had it and several other approaches and it was severe cleear, "cleared Roaring Fork Visual, runway 15". Well, that RNP approach path, lateral and vertical, looked mighty sporty!

Thanks again, GF