IFR Departure from unsurveyed airport

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charrois
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IFR Departure from unsurveyed airport

#1 Post by charrois » Wed Dec 13, 2017 4:15 pm

Hi everyone.

A quick question - is it legal (notice that I'm not asking if it's safe :-) to depart from an airport in IMC if that airport doesn't have any instrument approaches (and hence, is also unsurveyed for departures)? Obviously, the pilot would be responsible for their own terrain and obstacle clearance.

The reason I'm asking is that there are lots of airports in the prairies with no obstacles to speak of for hundreds of miles, so a visual climb to only a few hundred feet AGL will guarantee terrain and obstacle clearance in the airport vicinity. Of course, a lot of those airports are also under nothing but class G airspace, so that would raise the additional complication of them being uncontrolled making the pilot also responsible for their own traffic separation. However, many of those airports are also located quite close to nearby airports with instrument approaches which could be used if they have to get back down again in a hurry.

Not that I'm saying it's necessarily the safest thing to be doing, particularly if there are no airports nearby with approaches, but in light IMC in an area the pilot is familiar with, I can see how it might be tempting if it's in fact legal to do.

Thanks!

Dan
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dogfood
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Re: IFR Departure from unsurveyed airport

#2 Post by dogfood » Wed Dec 13, 2017 4:27 pm

No clue if it's legal but many operators have been doing it for years up north. Obviously you need to be familiar with the area before you go in there in hard imc
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charrois
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Re: IFR Departure from unsurveyed airport

#3 Post by charrois » Fri Dec 15, 2017 9:24 pm

It doesn't surprise me at all that some operators would do it, since it would certainly be tempting, particularly if familiar with the aerodrome's environment. But I'm still curious as to the legality of it, if anyone knows.

Dan
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Schooner69A
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Re: IFR Departure from unsurveyed airport

#4 Post by Schooner69A » Fri Dec 15, 2017 9:37 pm

Yes. Legal. And safe.
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dialdriver
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Re: IFR Departure from unsurveyed airport

#5 Post by dialdriver » Fri Dec 15, 2017 9:39 pm

Have a look at CAP GEN page 19 and AIM RAC 7.7 regarding non assessed departures. I have taken off IFR from airports in the north that were uncontrolled gravel strips into uncontrolled airspace with no IFR facilities and in controlled airspace at controlled airports without IFR facilities. You are required to provide your own obstacle clearance and must have a minimum 1/2 sm visibility. It is quite legal. An IFR clearance is required in controlled airspace.
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charrois
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Re: IFR Departure from unsurveyed airport

#6 Post by charrois » Fri Dec 15, 2017 10:04 pm

dialdriver wrote:
Fri Dec 15, 2017 9:39 pm
Have a look at CAP GEN page 19 and AIM RAC 7.7 regarding non assessed departures. I have taken off IFR from airports in the north that were uncontrolled gravel strips into uncontrolled airspace with no IFR facilities and in controlled airspace at controlled airports without IFR facilities. You are required to provide your own obstacle clearance and must have a minimum 1/2 sm visibility. It is quite legal. An IFR clearance is required in controlled airspace.
I had been under the impression that "not assessed" is what would appear in the departure procedure section of the aerodrome charts for those airports which for whatever reason hadn't been assessed for obstacle clearance but at least had an aerodrome chart in the CAP in the first place. If "not assessed" also applies by default to airports which don't have an aerodrome chart in the CAP, then that perfectly answers my question. Thank you!
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Diadem
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Re: IFR Departure from unsurveyed airport

#7 Post by Diadem » Fri Dec 15, 2017 11:29 pm

Aerodromes which are assessed for standard departure procedures meet the requirements that you can take if into hard IMC, so long as you have 1/2 SM visibility, cross the departure end of the runway at a minimum of 35 feet AGL, don't turn below 400 feet AGL, and climb at a minimum of 200 feet/NM; you can turn in any direction and fly off wherever you like, so long as you keep climbing at 200 feet/NM, because that'll keep you clear of any obstacles and get you to a safe IFR altitude. That's the case for most of the aerodromes on the prairies and up north, because there aren't really any obstacles to hit. For a "not assessed" aerodrome, you have to be able to climb visually to a usable IFR altitude, such as the sector altitude, 100 NM safe altitude, or an airway's MEA, or you need to somehow calculate the minimum climb gradient or routing required to avoid hitting anything; it's like a spec vis departure, but spec vis is a published procedure, and "not assessed" is entirely at your discretion. If you take off with 1/2 SM vis and VV001, there's no guarantee that you won't hit something even if you adhere to the requirements for the standard departure, so you need to make sure you can assess your own obstacle clearance, and typically the only way to practically do that is to remain in VMC until at a safe altitude.
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x-wind
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Re: IFR Departure from unsurveyed airport

#8 Post by x-wind » Sat Dec 16, 2017 5:28 am

You can also study the VNC charts to determine the area around the aerodrome and any obstacles that will effect it. As I recall this was the advice in the AIM. This question and many like it can be answered from that book.

If your studying for your INRAT use the study and reference guide and look up the CARs. They have the regulation numbers that are applicable to the topic. Very useful to read the exact laws.

Also there are not to many places left that have no obstacles for hundreds of miles especially when there is a strip around. Careful with that idea. Note the never ending tower NOTAMs.
Cheers
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dialdriver
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Re: IFR Departure from unsurveyed airport

#9 Post by dialdriver » Sat Dec 16, 2017 10:57 am

charrois wrote:
Fri Dec 15, 2017 10:04 pm
dialdriver wrote:
Fri Dec 15, 2017 9:39 pm
Have a look at CAP GEN page 19 and AIM RAC 7.7 regarding non assessed departures. I have taken off IFR from airports in the north that were uncontrolled gravel strips into uncontrolled airspace with no IFR facilities and in controlled airspace at controlled airports without IFR facilities. You are required to provide your own obstacle clearance and must have a minimum 1/2 sm visibility. It is quite legal. An IFR clearance is required in controlled airspace.
I had been under the impression that "not assessed" is what would appear in the departure procedure section of the aerodrome charts for those airports which for whatever reason hadn't been assessed for obstacle clearance but at least had an aerodrome chart in the CAP in the first place. If "not assessed" also applies by default to airports which don't have an aerodrome chart in the CAP, then that perfectly answers my question. Thank you!
True, not assessed appears in the CAP, but airports that are not in the CAP are also not assessed and the same guidelines would apply. Also, published departure procedures are not mandatory and you can take off IFR using your own 'not assessed' procedure. The published procedure merely provides a quantifiable and safe departure path and deviation from them needs to be done with care.
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Re: IFR Departure from unsurveyed airport

#10 Post by co-joe » Mon Dec 18, 2017 6:56 pm

Some options for a Not Assessed departure are;

climb visual to minimum IFR altitude before proceeding on course
sometimes a nearby aerodrome might have a 25 or 100 nm safe you can use, or call the ACC and ask for their minimum altitude in the area, use the AMA, MOCA of an airway, etc

climb the approach backwards (if there is one and you can meet its gradient)

build your own departure based on a VNC chart and take life into your own hands

there was an option about using knowledge of a local but I can't remember the wording. The cocktail napkin departure kind of idea. Safety third right?
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