What does it mean to takeoff under IFR?

Skid

Skid

Pre-takeoff checklist
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Skid
This is an embarrassing question, but I’m trying to wrap my head around takeoff minimums.

I understand the basic gist that they don’t really apply to part 91, but when reading some of the non standard minimums in my area just to get a basic idea for safety I start to confuse myself. It states “no pilot may takeoff from a civil airport under IFR unless...”

...which brings me to where I’m confused. What I’m wondering is for airports that have something like “Rwy 36: NA”, if the weather is beautiful out can they not use that runway if on an IFR flight plan? Or is it referring to the actual weather of 1000/3?
 
91.175(f) Civil airport takeoff minimums lays out the weather minimums for part 121, 125, 129, or 135 to depart IFR...cuz as you noted for part 91 it is 0/0
 
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Skid said:
This is an embarrassing question, but I’m trying to wrap my head around takeoff minimums.

I understand the basic gist that they don’t really apply to part 91, but when reading some of the non standard minimums in my area just to get a basic idea for safety I start to confuse myself. It states “no pilot may takeoff from a civil airport under IFR unless...”

...which brings me to where I’m confused. What I’m wondering is for airports that have something like “Rwy 36: NA”, if the weather is beautiful out can they not use that runway if on an IFR flight plan? Or is it referring to the actual weather of 1000/3?
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It would help if you could give an actual example.
 
Greg Bockelman said:
It would help if you could give an actual example.
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Here’s an example:
QPiu4.png


As Shawn pointed out the reference reg is 91.175(f) and then more specifically section (1) of that which describes the takeoff under IFR.

Reason I ask is I think I see part 135 aircraft taking off from the uncontrolled airport I fly out of fairly regularly on a runway noted NA like the above. Obviously it’s on severe clear days but I would imagine they are more or less required to get their IFR clearance on the ground and thus would be taking off “under IFR” as opposed to IMC.
 
They are taking off VFR even if they have an IFR clearance. So the NA is NA :)
Their clearance doesn’t apply until they enter controlled airspace (probably at 700’ AGL).
‘Under IFR’, means ‘under IFR conditions’.
 
Skid said:
Here’s an example:
QPiu4.png


As Shawn pointed out the reference reg is 91.175(f) and then more specifically section (1) of that which describes the takeoff under IFR.

Reason I ask is I think I see part 135 aircraft taking off from the uncontrolled airport I fly out of fairly regularly on a runway noted NA like the above. Obviously it’s on severe clear days but I would imagine they are more or less required to get their IFR clearance on the ground and thus would be taking off “under IFR” as opposed to IMC.
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You’re actually mixing and matching some different things. They’re taking off IFR from that runway because they meet the requirements of 91.175(f)(2), with 1 mile or more visibility for a single- or twin-engine airplane.

The NA for takeoff runway 35 is part of the obstacle procedure, and 91.175(f)(3) & (4) apply.
 
Is it possible that ATC has issued a takeoff clearance to "maintain own obstacle and terrain celarance" under VFR weather conditions? I thought part 135 ops were required to follow alt takeoff mins and ODPs when operating IFR. Part 91 it doesn't apply of course, although wise to heed.
 
"...part 135 aircraft taking off from the uncontrolled airport I fly out of..."

Not saying that this is the case in this instance, but 135 operators have FAA-approved Operating Specifications, detailed right down to pilot names and aircraft tail numbers, authorizing things not permitted by the regs as written.

Bob
 
Skid said:
would imagine they are more or less required to get their IFR clearance on the ground and thus would be taking off “under IFR” as opposed to IMC.
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Often times ODP (obstacle departure procedures) are not issued as part of a clearance out of uncontrolled fields leaving it up to the pilot to get to controlled airspace however they want in VMC. If they are issued the FICHU TWO DEPARTURE as part of their clearance then they are indeed limited to RWY 17.
 
chemgeek said:
Part 91 it doesn't apply of course, although wise to heed.
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Commercial operator regs are generally in addition to Part 91, not in place of it. Note that the reg segments mentioned here specifically state that they are for commercial operations.
 
MauleSkinner said:
So how does the climb gradient figure in if it’s not for obstacles?
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I didn't say "it's not for obstacles". You said that the "Rwy 35, NA" is a departure procedure, not a takeoff minimum. But it is clearly within the paragraph entitled "TAKEOFF MINIMUMS".

Screen Shot 2018-10-01 at 11.56.44 AM.png
 
dmspilot said:
I didn't say "it's not for obstacles". You said that the "Rwy 35, NA" is a departure procedure, not a takeoff minimum. But it is clearly within the paragraph entitled "TAKEOFF MINIMUMS".

View attachment 67709
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No, I said obstacle procedure.

Jepp charts make very clear the difference between the 91.175(f)(2) requirements and the 91.175(f)(3) & (4) requirements. Not so much the government pubs.
 
MauleSkinner said:
See the edit of that post.
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Your edit doesn't answer the question.

An obstacle departure procedure is a type of departure procedure. I don't know why you're trying to invent something called "obstacle procedure" and make it seem like it's something different compared to an obstacle departure procedure.

So what does "Rwy 35, NA" mean?
 
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MauleSkinner said:
They’re taking off IFR from that runway because they meet the requirements of 91.175(f)(2), with 1 mile or more visibility
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No. 91.175(f)(2) does not apply because 91.175(f)(1) does.
 
Its actually “RWY 35 NA-ATC.”
 
Skid said:
This is an embarrassing question, but I’m trying to wrap my head around takeoff minimums.

I understand the basic gist that they don’t really apply to part 91, but when reading some of the non standard minimums in my area just to get a basic idea for safety I start to confuse myself. It states “no pilot may takeoff from a civil airport under IFR unless...”

...which brings me to where I’m confused. What I’m wondering is for airports that have something like “Rwy 36: NA”, if the weather is beautiful out can they not use that runway if on an IFR flight plan? Or is it referring to the actual weather of 1000/3?
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The way I read it, in the example you gave, is that Rwy 35 IFR takeoffs are not authorized. The company may allow them to takeoff VFR and activate their clearance airborne.
 
DGlaeser said:
They are taking off VFR even if they have an IFR clearance. So the NA is NA :)
Their clearance doesn’t apply until they enter controlled airspace (probably at 700’ AGL).
‘Under IFR’, means ‘under IFR conditions’.
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No, Under IFR means under INSTURMENT FLIGHT RULES.
IFR exists even in uncontrolled airspace.
 
In my neck of the woods, an example of "NA minimums" is runway 36 at Hornell (KHTF), which specifies takeoff minimums for RWY 36 as "NA-obstacles". I would assume this means that departure from RWY 36 is not authorized IFR for part 135. (If you've ever flown out of there, you would know why this might be the case, as Hornell airport sits in a glacial bowl surrounded by tall hills. The RWY 18 departure is also a bit weird--it looks like you are not gaining on the ground as you climb out.) There is no ODP for RWY 36, only for RWY 18.
 
DGlaeser said:
They are taking off VFR even if they have an IFR clearance. So the NA is NA :)
Their clearance doesn’t apply until they enter controlled airspace (probably at 700’ AGL).
‘Under IFR’, means ‘under IFR conditions’.
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Are you saying that when you take off, say, from KVLL after getting your clearance on the ground, that you are not operating IFR until you reach controlled airspace? What if the bases are below 700? ;)

I don't think it has anything to do with meteorological conditions either... if you get your clearance on the ground and there is no explicit understanding that you are taking off VFR, you are taking off IFR even if ATC has no explicit control over airspace below 700. They only give you a heading to fly once you reach controlled airspace; you are still IFR below that, in my understanding (which could be wrong).
 
An important point from the FARs that many seem to miss is that there actually is a set of Visual Flight Rules and another set of Instrument Flight Rules.

VFR = 14 CFR 91.151 - 91.165
IFR = 14 CFR 91.167 - 91.199

Commercial operations will additional restrictions and requirements which limit their ability to operate VFR and require the adherence to takeoff minimums and departure procedures.
 
azure said:
Are you saying that when you take off, say, from KVLL after getting your clearance on the ground, that you are not operating IFR until you reach controlled airspace? What if the bases are below 700? ;)

I don't think it has anything to do with meteorological conditions either... if you get your clearance on the ground and there is no explicit understanding that you are taking off VFR, you are taking off IFR even if ATC has no explicit control over airspace below 700. They only give you a heading to fly once you reach controlled airspace; you are still IFR below that, in my understanding (which could be wrong).
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A Part 91 IFR pilot can operate in IMC in uncontrolled airspace, which is why the clearance starts "upon entering controlled airspace..." So if the bases are below 700' you are IFR but not on a clearance until 700'.
 
Shawn said:
91.175(f) Civil airport takeoff minimums lays out the weather minimums for part 121, 125, 129, or 135 to depart IFR...cuz as you noted for part 91 it is 0/0
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By the way, for anyone who doesn't know, it's important to be aware that if you don't meet the takeoff minimums, including the climb gradient requirement, then the obstacle departure procedure does NOT guarantee obstacle clearance.
 
DGlaeser said:
A Part 91 IFR pilot can operate in IMC in uncontrolled airspace, which is why the clearance starts "upon entering controlled airspace..." So if the bases are below 700' you are IFR but not on a clearance until 700'.
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The clearance starts "Nxxxx is cleared to <clearance limit> via <route>". The "upon entering controlled airspace" comes later on, as I recall - I could be misremembering since I've been operating out of a surface Class E airport for the last 4 years, but I'm fairly sure that's true. (I *have* gotten clearances out here that start "upon reaching" some altitude, "cleared to...", but that's only when picking up the clearance in the air.)

Whether that's true or not, you're still IFR from the moment you take off - I don't think it depends on meteorological conditions. If you say it does, can you cite a source?

And what about Part 135 pilots? Are you saying that below the floor of controlled airspace they're operating VFR and can't enter IMC?
 
DGlaeser said:
A Part 91 IFR pilot can operate in IMC in uncontrolled airspace, which is why the clearance starts "upon entering controlled airspace..." So if the bases are below 700' you are IFR but not on a clearance until 700'.
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Controlled, uncontrolled, clearance or not, the PIC is ultimately responsible for the safety of the flight. When you get the trouble T, you better heed that notification.
 
DGlaeser said:
A Part 91 IFR pilot can operate in IMC in uncontrolled airspace, which is why the clearance starts "upon entering controlled airspace..." So if the bases are below 700' you are IFR but not on a clearance until 700'.
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I think that makes sense because how can ATC give proper separation services in uncontrolled airspace. Part of it has to be on your own
 
benyflyguy said:
I think that makes sense because how can ATC give proper separation services in uncontrolled airspace. Part of it has to be on your own
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Everyone is agreed on that point, I think. My question was about Dennis's statement that the Part 135 guys are VFR until they enter controlled airspace. He agreed that that is not true for Part 91 pilots, that we are IFR below the Class E even if our clearance doesn't really apply until we get into the Class E airspace. If it's different for Part 135, I'd like to see a reference for that.

He also said that "under IFR" means "under IFR conditions" and if that means what "IFR conditions" usually means (meteorological conditions under which it's illegal to operate VFR), then I'm really confused because that goes against everything I've been taught.

I should add that Dennis was my finish-up CFII for a few months before my checkride, so I have a lot of respect for his knowledge and expertise. If there is something I don't understand here I'd definitely like to have it cleared up.
 
azure said:
Everyone is agreed on that point, I think. My question was about Dennis's statement that the Part 135 guys are VFR until they enter controlled airspace. He agreed that that is not true for Part 91 pilots, that we are IFR below the Class E even if our clearance doesn't really apply until we get into the Class E airspace. If it's different for Part 135, I'd like to see a reference for that.

He also said that "under IFR" means "under IFR conditions" and if that means what "IFR conditions" usually means (meteorological conditions under which it's illegal to operate VFR), then I'm really confused because that goes against everything I've been taught.

I should add that Dennis was my finish-up CFII for a few months before my checkride, so I have a lot of respect for his knowledge and expertise. If there is something I don't understand here I'd definitely like to have it cleared up.
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Saying that they are IFR or VFR means that they are operating under instrument flight rules or visual flight rules, respectively. If a pilot is flying in meteorological conditions that don't meet the requirements for VFR flight, then he or she must operate under instrument flight rules (i.e., 91.167 through 91.193). This is true regardless of whether the aircraft is in controlled or uncontrolled airspace. The regs don't require a clearance to operate under instrument flight rules (i.e., "be IFR") in uncontrolled airspace, but there are other parts of instrument flight rules that still apply. (91.179(b) is an example.)

The above is based on Part 91 rules. I'm not an expert on Part 135, but my understanding is that Part 135 flights have to comply with both Part 91 and Part 135 unless there is an exception spelled out somewhere.
 
Palmpilot nails it to theletter. If you're operating under IFR, then you have to comply with all IFR rules. If you are operating in less than the VMC conditions, then you are illegal if you are not IFR.
Uncontrolled airspace only get you out of the requiremetn to have an ATC clearance, all other IFR rules apply. Even on a CAVU day, if operating IFR, you need to comply with all the IFR rules.
 
flyingron said:
Palmpilot nails it to theletter. If you're operating under IFR, then you have to comply with all IFR rules. If you are operating in less than the VMC conditions, then you are illegal if you are not IFR.
Uncontrolled airspace only get you out of the requiremetn to have an ATC clearance, all other IFR rules apply. Even on a CAVU day, if operating IFR, you need to comply with all the IFR rules.
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I think I added my second paragraph after you responded to my post. Still good?
 
Palmpilot said:
Saying that they are IFR or VFR means that they are operating under instrument flight rules or visual flight rules, respectively. If a pilot is flying in meteorological conditions that don't meet the requirements for VFR flight, then he or she must operate under instrument flight rules (i.e., 91.167 through 91.193). This is true regardless of whether the aircraft is in controlled or uncontrolled airspace. The regs don't require a clearance to operate under instrument flight rules (i.e., "be IFR") in uncontrolled airspace, but there are other parts of instrument flight rules that still apply. (91.179(b) is an example.)
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Yes - that's 100% in agreement with my understanding. But @DGlaeser seemed to be saying something different, which is why I questioned him.
 
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I will add that although technically you don't have an active clearance below the Class E in the sense of separation services being provided explicitly as in controlled airspace, for all intents and purposes you are still "cleared" from other IFR aircraft since ATC will not clear anyone else into or out of that airport until either you are in controlled airspace and they can provide such services, or you cancel IFR. And that's as much separation services as they are required to provide in the Class E anyway - IFR traffic is not separated from VFR traffic there. What they can't do is prevent someone else from taking off and operating IFR (or even VFR, if conditions permit) in the Class G without getting a clearance or entering the Class E - though if they DO enter the Class E, they're operating illegally unless they have a clearance.
 
The FAA has held that departing IFR into uncontrolled airspace without a clearance for the overlying controlled airspace that you're heading for is careless and reckless.
That's the way it is for enforcment. Frankly, I think it is Constitutionally reprehensible to fall back on a junk reg like 91.13 for things like that. If you want to have a rule that says you need such a clearance, propose it, submit it for public review, and publish it. Don't just prosecute after the fact.
 
flyingron said:
The FAA has held that departing IFR into uncontrolled airspace without a clearance for the overlying controlled airspace that you're heading for is careless and reckless.
That's the way it is for enforcment. Frankly, I think it is Constitutionally reprehensible to fall back on a junk reg like 91.13 for things like that. If you want to have a rule that says you need such a clearance, propose it, submit it for public review, and publish it. Don't just prosecute after the fact.
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It's too bad that the FAA, ALJ, and NTSB overlooked the cloud-clearance issue that exists when the aircraft enters controlled airspace at 700 or 1200 AGL above a cloud layer. Then they wouldn't have needed to muddy the waters with the 91.13 BS.
 
Yep, the original charge was flew into the clouds VFR. When he said "Hey, I was IFR" then they dumped on for the goofy 91.13 violation rather than pointing out that at 1200' he wasn't going to be 1000' above the clouds he penetrated when he magically switched back to VFR at the edge of controlled airspace.
 
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