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Difference between a DP and a SID?

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cbattags

Member
Joined
Jun 13, 2005
Posts
8
Can someone shed some light in the main differences between the two.
My understanding is that DP's are designed for obstacle clearance and are found on the bottom of the airport diagram page (jepps). SID's are 2 types: Vector and Pilot nav. Designed to facilitate clearance delivery and transition form the airport to the enroute structure.
 
ya know...I don't really understand this either. Don't you always have obstacle clearance on an IFR procedure?

-mini
 
SIDs are developed for busier terminals, if ATC wants you to fly a SID they will clear you to fly it.

DPs are developed for obstacle clearance only and are not given as part of a clearance, pilots are expected to fly them on their own.

All will give obstacle clearance until safely en route
 
I talked to many controllers in many different cities about DPs published at the bottom of the jepp plates.

I would guess that 90% had no idea what I was talking about. They had no idea where the DPs came from and that they were no where in their SOPs. They could only guess that they were use when the tower was closed ... maybe.

Example ... SAV has a DP for every one of their runways printed on the bottom of the jepp. I asked the local controller when we would use these things. His first reply was that he had no idea what I was talking about ... go figure. I then explained to him what is was and I got the standard reply, "I've been a controller here for 14 years and I have never heard of any DP or any need for a DP off this airport. It is something we would never expect you to do and would probably question you if you followed them. Call jepp and ask them what it is because it is no where in our local terps manual or procedures."

I have gotten that response from over 20 airports where I have questioned the DPs. I think two or three controllers thought they had heard something about before and could only think that it was used when the tower was closed ... but for now fly runway heading ... cleared for takeoff.
 
A SID is a DP. A DP is a SID. We call them all DP's now.

Proceedural DP's are assigned for traffic management. Obstacle DP's are designed for obstacle protection. A departure proceedure can be for both obtacles, and traffic flow, and it's still a DP.
 
avbug said:
A SID is a DP. A DP is a SID.
While a SID is a DP, a DP is not necessarily a SID.

DP is the overall term for "Departure Procedures." They come in two flavors:

1. "Obstacle Departure Procedures" (ODP) which are designed for getting out of tight spaces

2. "Standard Instrument Departure procedures." (SID) which are designed for traffic flow.

The primary procedural difference between them is clearance. You are presumed to be cleared to fly an ODP unless you are instructed to the contrary (in which case you might decide to decline the clearance since waiting is usually preferable to a meeting with cumulus granite). But you never fly a SID without it being included in your clearance.

Not surprisingly the AIM explains it pretty well in § 5-2-6.
 
"You are presumed to be cleared to fly an ODP unless you are instructed to the contrary (in which case you might decide to decline the clearance since waiting is usually preferable to a meeting with cumulus granite). "

Why, then, don't local controllers know about these ODPs? Why do they have NO CLUE as to what I'm talking about when I ask them about DPs/ODPs at their home airport?

I have been instructed, by controllers, not to fly these things so I would guess that I am not "presumed" to be cleared for any of ODPs.

There must be more to this. Your simple answer doesn't hold water, and there is no cumulus granite popping up around SAV (in every direction) for hundreds of miles.
 
JECKEL said:
Why, then, don't local controllers know about these ODPs? Why do they have NO CLUE as to what I'm talking about when I ask them about DPs/ODPs at their home airport?

I have been instructed, by controllers, not to fly these things so I would guess that I am not "presumed" to be cleared for any of ODPs.

There must be more to this. Your simple answer doesn't hold water, and there is no cumulus granite popping up around SAV (in every direction) for hundreds of miles.


If you're asking why the controllers don't know anything about the "DPs published at the bottom of a Jepp plate", it's likely they've never even seen a Jepp plate for their airport. FAA controllers don't use Jeppesen for anything. We use NACO charts and plates. I've never seen a Jepp plate for the airport I work at, and I've been here more than five years. Never ask a controller a question about a Jeppesen plate or chart.

If you want to know what NACO charts say about SAV, see below:




IFR TAKE-OFF MINIMUMS AND (OBSTACLE) DEPARTURE PROCEDURES








Civil Airports and Selected Military Airports






ALL USERS: Airports that have Departure Procedures (DPs) designed specifically to assist pilots in avoiding obstacles during the climb to the minimum enroute altitude , and/or airports that have civil IFR take-off minimums other than standard, are listed below. Take-off Minimums and Departure Procedures apply to all runways unless otherwise specified. Altitudes, unless otherwise indicated, are minimum altitudes in MSL.


DPs specifically designed for obstacle avoidance are described below in text, or published separately as a graphic procedure. If the (Obstacle) DP is published as a graphic procedure, its name will be listed below, and it can be found in either this volume (civil), or a separate Departure Procedure volume (military), as appropriate. Users will recognize graphic obstacle DPs by the term "(OBSTACLE)" included in the procedure title; e.g., TETON TWO (OBSTACLE). If not assigned another DP or radar vector by ATC, this procedure may be flown to ensure obstacle clearance.

Graphic DPs designed by ATC to standardize traffic flows, ensure aircraft separation and enhance capacity are referred to as "Standard Instrument Departures (SIDs)". SIDs also provide obstacle clearance and are published under the appropriate airport section. ATC clearance must be received prior to flying a SID.








SAVANNAH, GA





SAVANNAH/HILTON HEAD INTL






DEPARTURE PROCEDURE:
Rwys 9, 36, climb runway


heading to 500 before turning. Rwy 18, climb runway

heading to 1100 before turning right. Rwy 27, climb

runway heading to 1200 before turning left.


If you want to know why the controllers don't use the above, it's because they have procedures written in their facility manuals to cover obstacle clearance when the Tower/Approach is operating. These procedures are not published outside the facility.

And if you want to know when you'd use the obstacle DPs published above, you're welcome to use them when the Tower/Approach is closed.

Did that answer all your questions? :)
 
JECKEL said:
"You are presumed to be cleared to fly an ODP unless you are instructed to the contrary (in which case you might decide to decline the clearance since waiting is usually preferable to a meeting with cumulus granite). "

I have been instructed, by controllers, not to fly these things so I would guess that I am not "presumed" to be cleared for any of ODPs.
No. You have been "instructed to the contrary."

If the routing given by ATC allows you to not hit anything based on your aircraft performance (which it should - that's one of the things vectors is =supposedly= all about) no problem.

You're right, though. In most radar situations, ATC doesn't know and doesn't care about the ODP. But, depending on where you are flying , you should.

I'm not sure what your water problem is.
 
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."

(from Jeppesen Air Traffic Control section, US O-1)

Here is a plain English example (my words, not from Jepp):

Consider the case of a departure from an airport at which the tower is closed (or, terminal radar is out of service). You have called FSS for clearance, and have been "cleared as filed", with no SID assigned. The ODP, if correctly flown, is a way for you to get from takeoff to the first enroute fix without hitting the terrain or an obstruction.

B-727
 

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