IFR Departure Procedures

121 is more restrictive than that as VMC is not an allowable alternative.

As for your #3, you can't very well have a vector absent radar, so not sure what you're saying there.
 
pavelump said:
If you are not given a clearance for a SID or radar vectors and an ODP exists, you must use the ODP.
Click to expand...

Interesting. I always thought they were just "good operating practice," but not necessarily mandatory.

Not that the Instrument Procedures Handbook isn't authoritative enough, but do you have a FAR and/or AIM reference to go along with this?
 
jrh said:
Interesting. I always thought they were just "good operating practice," but not necessarily mandatory.

Not that the Instrument Procedures Handbook isn't authoritative enough, but do you have a FAR and/or AIM reference to go along with this?
Click to expand...


AIM Par 5-2-6. Instrument Departure Proc - Obstacle Departure Proc - and Standard Instrument Departure Proc.


The AIM states that, if VFR, you can maneuver visually to avoid obstructions...Part 91.

Seagull has advised, Part 121/135 operators must comply with the ODP as textually published. I'd agree with that as well.

Now here's another layer. Do Part 121/135 operators have to be able to meet the SID/ODP climb gradients on a single engine? I think the answer to that is yes...they do. Regulations require the 'net flight path' to clear all obstructions either by a height of 35' vertically or 200' or 300' horizontally until 1500' agl or attainment of final segment climb speed, whichever is greater.

Do Part 91 operators have to meet this restriction? No...I don't think they do.

So what is 'net flight path'? It's the path found by reducing the regulatory climb gradient .8%.


Pretty good stuff...
 
seagull said:
121 is more restrictive than that as VMC is not an allowable alternative.

As for your #3, you can't very well have a vector absent radar, so not sure what you're saying there.
Click to expand...


Woops, I had edited that to try and be more clear, but I missed that part. What I meant to say was:

You would use an ODP unless one of the following exists:

1. You can visually depart from the airport; (if your ops specs allow...)
2. You have received a SID clearance; or
3. You have received radar vectors


As far as part 121 not allowing VMC departures, I'm not sure that it's in part 121 per se (at least I couldn't find it), but rather the Ops Specs of a particular airline which is just as controlling as part 121 yadda yadda yadda, but I think that you already said that...

I had to go look it up in our op specs (American Eagle) and it agrees w/ what you are saying. Of the several requirements that have to be met for a VMC departure, two of them state:

"The flight crew must comply with the Departure Procedures established for a particular airport by the FAA", and;

"At airports where a Departure Procedure has not been established, the airport diagram will be used in order to identify obstacles and obstructions around the airport."
 
At one time the Ops Specs were pretty different from carrier to carrier, with each POI pretty much doing their own thing. In the early 90s, Jerry Davis, then manager of AFS-400 (now works for Airbus flight safety) created the "New Standard Ops Specs". Now, all airlines start with the essentially same set of Specs, and each can tailor to their needs by applying various standard exemptions which they can apply for.

As for single engine performance, the answer is "no". The ODP is predicated on "all engine" performance. If you lose one, you are NOT guaranteed those gradients (although jets usually would make them). That is the reason for the EODP, and, absent that, it's up to the pilots, which is yet another reason you don't want the "fat, dumb and happy" breed up front.
 
seagull said:
At one time the Ops Specs were pretty different from carrier to carrier, with each POI pretty much doing their own thing. In the early 90s, Jerry Davis, then manager of AFS-400 (now works for Airbus flight safety) created the "New Standard Ops Specs". Now, all airlines start with the essentially same set of Specs, and each can tailor to their needs by applying various standard exemptions which they can apply for.

As for single engine performance, the answer is "no". The ODP is predicated on "all engine" performance. If you lose one, you are NOT guaranteed those gradients (although jets usually would make them). That is the reason for the EODP, and, absent that, it's up to the pilots, which is yet another reason you don't want the "fat, dumb and happy" breed up front.
Click to expand...

From a former 4 engine guy... I think you are refering to "One Engine Inoperative" rather than "Single Engine" in the post above. Other than that minor edit, I agree with the above.
 
seagull said:
As for single engine performance, the answer is "no". The ODP is predicated on "all engine" performance. If you lose one, you are NOT guaranteed those gradients (although jets usually would make them). That is the reason for the EODP, and, absent that, it's up to the pilots, which is yet another reason you don't want the "fat, dumb and happy" breed up front.
Click to expand...


Good point....I had to go back and look some things up. I thought the net flight path was predicated on engine out...but it is all engines operating...and the net flight path must clear all obstructions by 35' vertically or 300' laterally.

All Part 121 airlines I've worked for have taken into account clearing these obstructions engine out in their engineering analysis of each departure. If the climb performance could not meet minimum climb gradients engine out...then the company would publish a special procedure to be flown if an engine quit.

Anytime I'm looking at a climb gradient for departure, be it a SID or IFR Departure Procedure (ODP)...I'm always thinking engine out...and if the airplane can't meet the gradient...I'm looking for other options.
 
Fish

You're right, good catch. Funny I would write that, as I never have even flown a jet with fewer than 3 engines!
 
cime_sp said:
Pavelump....where you at these days? Still playing any music?
Click to expand...


Nah, not so much anymore. I'm living in Dallas working for the man (American Eagle). Biding my time in the Saab until I can transfer into the jet and back to Chi town.
 
You must log in or register to reply here.
Back
Top