ODP and Takeoff Minimum Climb Gradients

Edlc82002

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Edlc82002
Was having this discussion with someone the other day and we seemed to have different understandings on this .

Is it required to meet or exceed the listed climb gradient(s) listed under tge nonstandard Takeoff Minimums when departing a runway and electing to fly it’s published Textual ODP?

...OR...

Do these climb gradients only apply if electing to NOT fly the textual ODP and when wanting to make a turn directly on course at the standard 400’ AGL instead (meaning this non standard climb requirement will ensure obstacle clearance in all directions) ?

Put another way, are ODPs created as an option if you CANT make those steeper climbs (and are made to satisfy the standard 200’/NM), or are those steep climbs actually a requirement to fly to the ODP in the first place? The photo shows the airport in question, however it really applies to anywhere.

Often you’ll SIDs with minimum requirements right on the plate making it pretty obvious. With these textual ODPs the information is sort of separated (especially in FAA documents which have the T/O mins and DPs in different paragraphs).

I have my opinion/idea on this (which is to assume these minimums should be adhered to, better safe than sorry right?) but i was surprised to hear this other persons point of view on this.

Thanks!
 

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If you're going to fly the ODP, the climb gradients are required as noted. Otherwise, you hit something.

Here's the FAA version, which I'm more familiar with.

Off Rwy 11, for example, you either do the departure procedure or the VCOA.

If you are doing the departure procedure, you need either:
- Ceiling 1100, visibility 2 1/4 if you can maintain a climb gradient of 558 ft per nm to 4200
or
- Standard visibility if you can maintain a climb gradient of 830 ft per nm to 3600.

In either case, you need to climb heading 111 to 4000 before proceeding on course.

If you're going to do the VCOA, there is no climb gradient required (other than the standard 200 ft per nm) but you need ceiling 3500 and visibility 3 sm.

This leaves out the discussion of whether ODPs and takeoff minimums are required for Part 91 operations, which is a different question that I don't think you're asking.

2021-06-10_15-35-49.png
 
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Thank you! Yes this was my understanding as well. If it was that clear cut of an either/or situation I feel like it would be published as such.

And yes the Part 91 aspect of it is a difficult discussion altogether. I fly Part 91, but my thinking is if the 121 and 135 guys have these requirements for safety, then there has got be a good reason for it, and no reason for me not to follow as well.
 
Messing up an ODP or worse, ignoring it can kill you. Good conversation. I always check to be sure I meet the minimum published gradient before I go. Pretty sure there was a guy departing an airport in VT in IMC not very long ago who met his demise with terrain not following an ODP.
 
Do these climb gradients only apply if electing to NOT fly the textual ODP and when wanting to make a turn directly on course at the standard 400’ AGL instead (meaning this non standard climb requirement will ensure obstacle clearance in all directions) ?
Just to directly address this…if an ODP is published, the published gradient only applies to the ODP; diverse departures are not protected.
 
Just to directly address this…if an ODP is published, the published gradient only applies to the ODP; diverse departures are not protected.
Thank you, yes this was my understanding as well
 
Was having this discussion with someone the other day and we seemed to have different understandings on this .

Is it required to meet or exceed the listed climb gradient(s) listed under tge nonstandard Takeoff Minimums when departing a runway and electing to fly it’s published Textual ODP?

...OR...

Do these climb gradients only apply if electing to NOT fly the textual ODP and when wanting to make a turn directly on course at the standard 400’ AGL instead (meaning this non standard climb requirement will ensure obstacle clearance in all directions) ?

Put another way, are ODPs created as an option if you CANT make those steeper climbs (and are made to satisfy the standard 200’/NM), or are those steep climbs actually a requirement to fly to the ODP in the first place? The photo shows the airport in question, however it really applies to anywhere.

Often you’ll SIDs with minimum requirements right on the plate making it pretty obvious. With these textual ODPs the information is sort of separated (especially in FAA documents which have the T/O mins and DPs in different paragraphs).

I have my opinion/idea on this (which is to assume these minimums should be adhered to, better safe than sorry right?) but i was surprised to hear this other persons point of view on this.

Thanks!

Hope you can get the message across to that 'other person.'
 
Yeah.... I was certainly scratching my head after the conversation because I was certain that my understanding on the subject was correct, and was always what Ive abided by. Thats why I was baffled at their certainty that I was wrong about this.

Like even if I was “wrong”, Id rather be wrong about something and have it err on the side of caution, rather than danger. Thanks for the input everyone!
 
I had the same misconception until an instrument takeoff from South Lake Tahoe (TVL) made me realize that I probably would not have survived if I had attempted to fly the ODP to the south in a Cessna Cutlass. Since then, it has been clear to me: published departure procedures don't guarantee terrain and obstruction clearance unless you meet the stated minimum climb performance.

https://skyvector.com/?ll=38.8937900942175,-119.99524066369813&chart=16&zoom=3
 
Up until around 1996, the Air Force was stupendously ignorant of takeoff minimums and departure procedures. We were taught that only the "inverse-A" NA applied to us. We used our own takeoff minimums and alternate minimums, so the "inverse-T" and "inverse-A" didn't apply to AF operations. Then a C-130 hit a mountain in Jackson Hole, WY and everyone got smart on how dumb we were. They hammered the crew in the accident, but the truth is that the crew was just doing what they were taught (or not doing what they weren't taught). After the accident, the Air Force's Advanced Instrument School sent some of their folks out into the field and gave rated pilots instrument quizzes to see where we were lacking knowledge, with an emphasis on takeoff minimums and departure procedures. After the results of those quizzes, the Air Force started a re-education program focusing on those specific area and it became a point of emphasis. Now, I think they do I pretty good job teaching this stuff in flight school, but sad that it took 9 people dying to do it.
 
Up until around 1996, the Air Force was stupendously ignorant of takeoff minimums and departure procedures. We were taught that only the "inverse-A" NA applied to us. We used our own takeoff minimums and alternate minimums, so the "inverse-T" and "inverse-A" didn't apply to AF operations. Then a C-130 hit a mountain in Jackson Hole, WY and everyone got smart on how dumb we were. They hammered the crew in the accident, but the truth is that the crew was just doing what they were taught (or not doing what they weren't taught). After the accident, the Air Force's Advanced Instrument School sent some of their folks out into the field and gave rated pilots instrument quizzes to see where we were lacking knowledge, with an emphasis on takeoff minimums and departure procedures. After the results of those quizzes, the Air Force started a re-education program focusing on those specific area and it became a point of emphasis. Now, I think they do I pretty good job teaching this stuff in flight school, but sad that it took 9 people dying to do it.
Also, the textual ODP at KJAC was a clusterF at the time. I wrote an article about it in 1997 for the ALPA magazine (attached).
 

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Also, the textual ODP at KJAC was a clusterF at the time. I wrote an article about it in 1997 for the ALPA magazine (attached).
Great article. Thanks for sharing!
 
Up until around 1996, the Air Force was stupendously ignorant of takeoff minimums and departure procedures. We were taught that only the "inverse-A" NA applied to us. We used our own takeoff minimums and alternate minimums, so the "inverse-T" and "inverse-A" didn't apply to AF operations. Then a C-130 hit a mountain in Jackson Hole, WY and everyone got smart on how dumb we were. They hammered the crew in the accident, but the truth is that the crew was just doing what they were taught (or not doing what they weren't taught). After the accident, the Air Force's Advanced Instrument School sent some of their folks out into the field and gave rated pilots instrument quizzes to see where we were lacking knowledge, with an emphasis on takeoff minimums and departure procedures. After the results of those quizzes, the Air Force started a re-education program focusing on those specific area and it became a point of emphasis. Now, I think they do I pretty good job teaching this stuff in flight school, but sad that it took 9 people dying to do it.
That accident got a lot of press back then.

obviously there are plenty of things to learn, as with any accident, but what struck me today was the last words on the CVR... “My radar altimeter just died.” How often have we defaulted to “that’s just an indication problem” for something like low fuel, discharging or overcharging ammeter, etc., or allowed ourselves to be biased by the gizzy when it was the raw data that was good, or simply chose to continue an approach when the course deviation didn’t match the moving map because we had the wrong frequency or waypoint?

Fortunately for most of us, the consequences aren’t this severe.
 
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