Why are ODPs not required in IMC?

Martin Pauly said:
With a good climb gradient (think turboprop or jet) even a departure straight towards those towers is not an issue.

- Martin
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I was going to point out that those obstacles can be an issue for a jet, since all of our performance calculations are based on one engine inoperative, and those tall towers can be limiting at that distance.

But I ran an airport analysis app, and apparently there are some close-in obstacles that are much more limiting and require almost a 5% gradient, even factoring in that we wouldn’t use the last 1000 feet of runway.
 
Sounds great.

So ... why there aren't such apps for typical small GA planes?

Why must we instead try to figure out whether a takeoff is safe, based on manual calculations with an input of data from digging deep into the back pages of the AF/D, and the performance tables in the POH?
 
NoHeat said:
Sounds great.

So ... why there aren't such apps for typical small GA planes?

Why must we instead try to figure out whether a takeoff is safe, based on manual calculations with an input of data from digging deep into the back pages of the AF/D, and the performance tables in the POH?
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Because most GA pilots are too cheap?
 
MauleSkinner said:
Because most GA pilots are too cheap?
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That too. But, I would substitute "GA pilot" with "light airplane pilots." My corporate GA pilot friends who operate Part 25 business jets buy runway-specific performance data, usually from APG. (Aircraft Performance Group). Then again, those Part 25 jets will meet Part 25 takeoff flight path performance requirements.
 
NoHeat said:
Sounds great.

So ... why there aren't such apps for typical small GA planes?

Why must we instead try to figure out whether a takeoff is safe, based on manual calculations with an input of data from digging deep into the back pages of the AF/D, and the performance tables in the POH?
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There is for the Bonanza and Baron line of airplanes. Search the iOS app store for "Bonanza Performance" and "Baron Performance". You enter your model, weight and enter your airport, it pulls in the METAR data and tells you your takeoff and landing distance. Now, it doesn't do obstacle analysis, but hey, it's a free app.

If there isn't such an app for the model of airplane you fly, it's just because someone hasn't developed it yet. So you could be the first to do so.
 
I just now tried it. Very nice!

If they added one more thing, a calculation of climb gradient feet per Nm), then it would be easy and fast for the user to compare to the takeoff minimums for the airport, especially now that ForeFlight takes you to the correct page of the chart supplement to find those minimums.
 
Trogdor said:
https://airfactsjournal.com/2021/11/its-time-to-reform-obstacle-departure-procedures/

Guys got a point. Not sure why ODPs are basically footnotes to IFR flying?!
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I like the idea of reorganizing the FAA charts to put ODPs near the airport diagram and approaches, but as a recently-minted instrument pilot, I know that ODPs are recommended and can be flown without being assigned by ATC, and if you don’t know that as an instrument-rated pilot, you should. The accident pilot in this case flew a left-hand pattern to an airport in the mountains that had a right-hand pattern. So him not knowing about the ODP wouldn’t surprise me.

Bottom line is if you’re flying a single-engine airplane out of an airport in the mountains at night and in IMC, you should be pretty curious about what might be lurking in the clouds.

So reorganizing the chart structure? Good idea. Graphical depictions of ODPs? Good idea. But I tend to doubt either would have helped this guy.

If you’re flying in the mountains out of unfamiliar airports and not following a published ODP, I really wonder how much you value your own hindquarters.
 
That KRHP ODP has more than the usual number of traps. First, it is essentially a VCOA but not stated as such. Then, it has a route ODP but only after climbing to 4,900 within 3 miles of the airport. Add to that a ceiling requirement of 3,400, which is not required at all for Part 91. Full of traps.
 
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Interesting conversation, sorry for reviving an old thread. I fly out of an airport with high terrain both east and west. Last time I flew with an instrument student, I had him include an ODP in the flight plan. When we got the clearance (uncontrolled airport), the ODP was not included; I told him to fly it anyway. Center asked "what are you doing"? His reply, "flying the ODP as filed to avoid terrain". Their response "Oh, ok". I make sure my instrument students know that if an ODP exist, it is vital to keeping them out of the rocks at night or in IMC.
 
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RockyMtnFlyer said:
Interesting conversation, sorry for reviving an old thread. I fly out of an airport with high terrain both east and west. Last time I flew with an instrument student, I had him include an ODP in the flight plan. When we got the clearance (uncontrolled airport), the ODP was not included; I told him to fly it anyway. Center asked "what are you doing"? His reply, "flying the ODP as filed to avoid terrain". Their response "Oh, ok". I make sure my instrument students know that if an ODP exist, it is vital to keeping them out of the rocks at night or in IMC.
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I think I said this here before, but here goes again. This happened to me too in Vermont. The controller asked me what I was doing when I called up. That was a training flight that ran late, we were in the mountains. ODPs were just a concept at that point in my training, that flight, 500 foot ceilings, clouds obscuring the mountains and pitch black when we got airborne, I became a believer in ODPs. My SOP now is to tell the controller that clears me that I will be flying the ODP. I always check for an ODP in preflight if I'll be flying into IMC.
 
Out west in Nevada ODPs are common. At KVGT (North Las Vegas) there is the Northtown 5 SID and a separate ODP, the Boulder City One. For those interested in visiting Las Vegas next month for the Formula 1 race, and landing at KVGT, it would behoove you to become familiar with the NOTWN5. ATC here tells me that this SID is a top contender for the most pilot deviations of published SIDs.

I would also recommend pilots become acquainted with the Digital Terminal Procedures Supplemental publication. The last page has a chart for easily converting those pesky feet/NM numbers to useful FPM climb rates, since many ODPs don't include the conversion chart. I print this chart out and give a copy to all my students. It's available as a PDF from 1800wxbrief.com .

When I depart an uncontrolled field like KEED on an IFR flight plan, the clearance does include "...depart KEED via the published ODP..."

Hope this is useful information!
 
Thank you for plenty of common sense points here as common sense is not all that common!
 
Maybe this thread should be a sticky.
 
Ramblin said:
I would also recommend pilots become acquainted with the Digital Terminal Procedures Supplemental publication. The last page has a chart for easily converting those pesky feet/NM numbers to useful FPM climb rates, since many ODPs don't include the conversion chart. I print this chart out and give a copy to all my students. It's available as a PDF from 1800wxbrief.com .
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In you don’t have the chart, access to it, or don’t feel like interpolating, the math isn’t hard. Ground Speed/60 x the minimum ft/nm required = minimum FPM.
 
ODP reform is in the current bill.
 
Recently I spent a good amount of time trying to make ForeFlight draw an ODP for a departure I had coming up. ODPs aren’t usually that complicated but it’s nice if the gps can draw the lines and even better if auto pilot can follow it if needed. I agree with author that it wouldn't take much these days to use the tech we have to make ODPs as digital as approaches are. Seems just a matter of time before ForeFlight adds ODPs to the procedure functionality and that would be a very good thing for everyone.
 
DaveInPA said:
I agree with author that it wouldn't take much these days to use the tech we have to make ODPs as digital as approaches are.
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They do, in a way. They call them SIDs.

The complexity of ODPs vary significantly based on the area in which you fly and the terrain in that area.
 
I was lucky that the airport I did my instrument checkride at had an ODP with a climb in hold instruction. If you entered the hold you accomplished two things: you demonstrated you knew about ODPs and you knocked the holding task off the list of things you had to demonstrate.
 
DaveInPA said:
Recently I spent a good amount of time trying to make ForeFlight draw an ODP for a departure I had coming up. ODPs aren’t usually that complicated but it’s nice if the gps can draw the lines and even better if auto pilot can follow it if needed. I agree with author that it wouldn't take much these days to use the tech we have to make ODPs as digital as approaches are. Seems just a matter of time before ForeFlight adds ODPs to the procedure functionality and that would be a very good thing for everyone.
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What airport were you departing from
 
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