aterpster
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aterpster
That is correct. But, the overlying Class E airspace in which they do provide separation is either 700 or 1,200 feet above you.
Can an instrument rated pilot take off in IMC without a clearance?
- Thread starter FORANE
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mscard88
Touchdown! Greaser!
Usually gets worse right after sunrise has been my experience until it eventually burns off.
Caramon13
Pattern Altitude
Right. And back to the OP's situation:
class G - that has ground fog 1/4 vis, 100 ceiling, and is clear above the low fog layer.
If that's truly the case then as others have said, you could take off without a clearance. If Class E is 700 feet up, you'll need an IFR clearance before you hit that airspace since you can't maintain cloud clearances at that point. If it's at 1200, you should actually be fine since you'll have class G all the way up to that altitude, and 1200-100 = 1100 (which is about 100 feet MORE than the cloud requirements for Class E). If this is night time, that changes the requirements for Class G of course.
You may actually have to deal with VFR traffic as people already said. Coming out of the fog you could encounter VFR traffic since separation is not provided. In the OP's situation, once you get to E you could stay VFR, or if the layers came up a bit just get clearance in the air if you wanted to maintain that altitude or just go higher to maintain VFR.
I think the problem is getting back, or landing at a field and requiring a clearance to do so. If in doubt I'll always file an IFR plan to be safe. Flew down to KAPF one night in hard IMC. You should have heard all these people who didn't plan ahead asking for pop up clearances from miles out. Felt good to know that I was already on a clearance and I had a whole heck of a lot of less stress.
One thing NOT to do is take off and expect to get your clearance below a cloud deck and find that ATC can't clear you right away. Now what do you do?
roncachamp
Final Approach
You maintain VFR, unless you foolishly departed in IMC. In that case you have to decide which FARs you're going to violate.
Yes, but maintaining VFR might not be so easy. Put yourself in a VFR "hold" in VMC or turn around and go back to the airport are the best choices. But it puts you in a situation where you might give in to the temptation of climbing on up without a clearance. You can't do that! You're not doing ATC any favors either. They dont like to be pressured that way. (what does this guy think he is doing?) If you took off in IMC you're pretty much already screwed. Be lucky to make it out alive and certificate intact if you do that, I would say. This is why most commercial ops have specs against even trying to do it that way. Best to get your clearance on the ground if there is IMC to deal with soon.
Further, as I've already stated, noodling around in IFR below a transition area when you don't have clearance for the overlying controlled airspace has been determined in the past to be reckless.
Yes, I agree. This has been my experience also.
Just was curious as I had heard it was legal to do this sort of thing. Seems in reality it is a technique likely hard to utilize while staying legal.
You can do it safely in VMC. Just take off and pick up your IFR clearance in the air. Its when its low IMC that its dicey.
kyleb
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Drake the Outlaw
No doubt the airplane hit a mountain and killed the executives. However, the sectional shows a minimum safe altitude of 2300' in that area, and field elevation is 660'. Those guys were apparently down very low in IMC and blindly ran into a hill. Just a bad deal.
Kritchlow
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Okay.... But are not there places in Alaska that this is feasible??
I'm not an Alaskan expert so maybe not... Just though there was a lot of G there.
roncachamp
Final Approach
You can depart and operate in IMC without an IFR clearance as long as you can adhere to all applicable FARs. Where the floor of Class E airspace is 1200' AGL or less that's just not possible. You need a cruising altitude that is 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown and it has to be a cardinal altitude correct for direction of flight.
aterpster
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aterpster
There are some area where Class G still goes up to 14,500, but not many. The base of most Class E airspace is 1,500 unlike the other 49 states. Also, most if not all, of Alaska is in a designated mountainous area.
aterpster
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aterpster
Unless this type of departure is done in a designated mountainous area. Also, assuring that there is no rising terrain or towers within 4 miles in all directions would even be a challenge for FAA flight inspection airplanes.
Kritchlow
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Kritchlow
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Thanks
roncachamp
Final Approach
None of the Instrument Flight Rules are Alaska-specific.
roncachamp
Final Approach
The base of Class E airspace is 1,500' AGL where terrain exceeds 14,500' MSL. Elsewhere in Alaska blue vignette indicates a Class E floor at 1,200' AGL just as it does in the contiguous US.
Alaska pilots do a lot of scud running, clear of the clouds and flying close to the ground. I flew, semi safely, in 600' ceilings all the way down the coast from Juneau to Ketchikan in the rain. I even talked to ATC and got a weather report and talked to a local pilot who said he was going and it was "ok". I made it. Rained all day. I was over the inland passage bay the whole time with clouds 100' above me (legal as I was in Class G). Not really recommending it, but its not uncommon. I also had weather reporting along the way and some alternates and PLENTY of fuel. That place gets more rain than just about anywhere in the world. I've talked to pilots who have done it at 100'! Now that I wouldnt do. He was caught though. It just kept getting lower and lower toward his destination. He was too scared to turn around. Fortunately it didnt go to the deck. A lot of those guys fly VFR only so IFR is not really an option for them, no charts no deice. I had some friends that did IFR into Juneau from Cordova and they made it in. Juneau has a lot of terrrain and some pretty interesting approaches. Take a look at them. That place has pretty high MEAs and ice in the clouds a lot. Going lower and lower into the unknown, that is a recipe for disaster. That 100' guy was lucky. That is a lesson in what NOT to do.
There was another time, this pilot went through this pass at like tight above the pass, right below the clouds. Get this, ATC told him, in the weather briefing that is was "open" and "pilots were getting through". That was not good, but it was only one spot. Fly the gunsite clear of the clouds and a big deep valley opens up on the other side. Then into the town down there. Rain all the way. That pass followed a road and there was an "emergency" landing strip at the bottom of the pass. But no buildings. Just a grass strip and a cloudy cold rainy hell of a place right where Canada meets Alaska between Whitehorse and Haines.
Alaska coast, pilots always have "weather in the cockpit". Look up, theres the weather! Damn weather is getting my knee wet.
Thats sort of how it is up there on that rainy coast. Flying pretty low. Stay clear of the clouds. But you have to be able to turn around and go back. Dont get "boxed in". Just because its Alaska doesnt mean you have immunity. Always have an "out", an alternate plan B. A lot of those guys know what they are doing but they have more than their share of accidents too.
There was another time, this pilot went through this pass at like tight above the pass, right below the clouds. Get this, ATC told him, in the weather briefing that is was "open" and "pilots were getting through". That was not good, but it was only one spot. Fly the gunsite clear of the clouds and a big deep valley opens up on the other side. Then into the town down there. Rain all the way. That pass followed a road and there was an "emergency" landing strip at the bottom of the pass. But no buildings. Just a grass strip and a cloudy cold rainy hell of a place right where Canada meets Alaska between Whitehorse and Haines.
Alaska coast, pilots always have "weather in the cockpit". Look up, theres the weather! Damn weather is getting my knee wet.
Thats sort of how it is up there on that rainy coast. Flying pretty low. Stay clear of the clouds. But you have to be able to turn around and go back. Dont get "boxed in". Just because its Alaska doesnt mean you have immunity. Always have an "out", an alternate plan B. A lot of those guys know what they are doing but they have more than their share of accidents too.
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aterpster
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aterpster
I stand corrected.
denverpilot
Tied Down
Nitpick: Cardinal altitude is not mandatory below 3000' AGL. Doesn't apply. You guys have to assign them, but we don't have to fly them if not assigned. In this case, no assignment so not required.
And I bet if I tried moderately hard I could find a very large swath of land in Kansas, Nebraska, South Dakota, or North Dakota with no charted obstacles above 100' AGL, nor significant terrain elevation changes. The advent of wind farms has made that slightly more challenging but not impossible.
Yup. Easily found two charted ranch airports in South Dakota with no obstacles charted or even in the obstacle database between them above 100' AGL. Took 30 seconds in Foreflight.
No approaches either so you'd better have some visibility at each end, but you wouldn't need to remain VMC in-between them.
Not populated areas either, so one could argue 500' AGL is ok, but it could all be done 1000' AGL.
Not that I have any intention nor desire to do anything like this. Simply pointing out that your assertion that it's "impossible" is inaccurate.
Not "impossible". Just incredibly dumb.
roncachamp
Final Approach
We're talking about IFR flights solely in uncontrolled airspace, ATC won't be assigning anything.
Cardinal altitude is mandatory for IFR flights in uncontrolled airspace. Relief from the hemispheric rule for cruising altitudes within 3000' of the surface is provided only to VFR operations.
The minimum altitude is not 1,000 feet above the highest charted obstacle, it's an altitude of 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown. Obstacles not more than 200' AGL constructed away from airports do not require FAA notification so would not necessarily appear on any charts or in any database.
Please explain how one could argue 500' AGL is OK for an IFR flight.
What are the two airports and the cruising altitude you've selected to illustrate that my assertion is inaccurate?
The 200' AGL is important. It's already added into the OROCA numbers on the chart. We were flying home on a slightly different route than normal (we had swung over to HKY to get fuel and since Margy was along and it was a nice clear day I wasn't IFR). Margy noted a small tower sitting on the peak of a local hill marked as "tower" but not with an obstruction symbol. I pointed out that it was probably only about 50' tall and while a nice visual landmark, didn't fit the definition of an obstruction.
Those of us who got broadcast radio licenses back in the day know that we often built our towers at 199' so that we didn't have to worry about FAA issues when the bulbs blew out.
Those of us who got broadcast radio licenses back in the day know that we often built our towers at 199' so that we didn't have to worry about FAA issues when the bulbs blew out.
roncachamp
Final Approach
When FAA personnel determine the various minimum altitudes they assume that wherever an obstruction can be erected without them being notified of it someone has erected such an obstruction. In the unlikely event of an enforcement action I think it unlikely a pilot would be held to a lesser standard.
Palmpilot
Touchdown! Greaser!
That can happen on an IFR clearance too.
EdFred
Taxi to Parking
No. Because a flight plan would have been filed. Flight plans always prevent pilot induced accidents.
denverpilot
Tied Down
That's exactly what I said.
By which reg? I don't see it, but I am not arguing that it's not there.
It's a chicken and egg problem. If it's not charted or in the database, how would someone know it's there? If a tree falls in the forest...
I couldn't find anything against it. Again, feel free to quote the reg. I'm not planning any flight like this, it's just a mental game for the thread.
Only one of them has an identifier so I didn't bother to post. The other has a ranch name. Could probably find an example with two airports that have identifiers if I have some time to look around tonight.
But we'll have to cover the obstacle thing first. If the assumption is that the whole world is littered with 199' obstacles below any possible flight path in the boonies, it changes the scenario significantly.
Here, I took a sec and grabbed what may be a bad example since I just slammed through it on my phone at work here...
1D8 - 3FU
And in case you're wondering if the tower is too close...
Granted, the obstacles are the kicker almost everywhere else you look around even up there in the boonies. And those are of course, what would kill you.
And repeating the disclaimer, it's insanely dumb. This is just for thread fodder. Not ever ever gonna do it.
Just a quick scroll around on the map, a number of routes from 3G2 to the private strips near the Agassiz Nat'l Refuge or even the Private Cox-Coyour Memorial to the northeast probably work also.
Think you can even squeak past the charted tower and go up to Erickson private there further northeast too. Not an obstacle in sight and the airports there are within about 20' of each other MSL. Heh. Flat, nothing-land.
mscard88
Touchdown! Greaser!
EdFred
Taxi to Parking
They do? How so?
Don't you watch the news?!?!?!?!
"A Cessna Cherokee crashed today in a field...blah blah blah...a flight plan was not filed."
mscard88
Touchdown! Greaser!
I guess I don't follow you unless you're saying that in jest?
roncachamp
Final Approach
This is exactly what you said:
91.179(b)
You assume it's there because it can be there without being charted or in the database.
91.177 Minimum altitudes for IFR operations.
(a) Operation of aircraft at minimum altitudes. Except when necessary for takeoff or landing, or unless otherwise authorized by the FAA, no person may operate an aircraft under IFR below—
(1) The applicable minimum altitudes prescribed in parts 95 and 97 of this chapter. However, if both a MEA and a MOCA are prescribed for a particular route or route segment, a person may operate an aircraft below the MEA down to, but not below, the MOCA, provided the applicable navigation signals are available. For aircraft using VOR for navigation, this applies only when the aircraft is within 22 nautical miles of that VOR (based on the reasonable estimate by the pilot operating the aircraft of that distance); or
(2) If no applicable minimum altitude is prescribed in parts 95 and 97 of this chapter, then—
(i) In the case of operations over an area designated as a mountainous area in part 95 of this chapter, an altitude of 2,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown; or
(ii) In any other case, an altitude of 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.
(b) Climb. Climb to a higher minimum IFR altitude shall begin immediately after passing the point beyond which that minimum altitude applies, except that when ground obstructions intervene, the point beyond which that higher minimum altitude applies shall be crossed at or above the applicable MCA.
The coordinates of the fields are sufficient.
I don't know about the world, in the US Adverse Assumption Obstacle criteria are used in determining minimum altitudes. The height is 200' AGL.
We don't even have to examine obstacles. You must operate at an even cardinal altitude, the only one within Class G airspace is 2000 but it's less than 700' above the ground.
Palmpilot
Touchdown! Greaser!
They do? How so?
He forgot to include a "wink" emoticon.
mscard88
Touchdown! Greaser!
denverpilot
Tied Down
Yup, there ya go. Mental exercise, over with.
Like I said, no plans to ever do it, and it shows by 91.179 not even sticking in my head... it was "impossible" after all, so there was little point in remembering that one, operationally... since I squarely "live" below FL180 and probably will for a looooong time.
Cool stuff. Thanks for the references.
DavidWhite
Final Approach
As roncachamp said - in alaska most places are still 700' or 1200' class g.....if you want to file its best to get your clearance on the ground. I've departed in good weather VFR though and picked up my clearance enroute to a destination with bad weather. IFR not only is it illegal to blast off without a clearance, it's a really bad idea.
In my humble opinion, no.
While no clearance is available or required in uncontrolled airspace, you'd better have a clearance for the overlying controlled airspace. The FAA has held that making such a departure without the clearance for the overlying airspace is "careless and reckless."
If you are at a Class G airport, and if there is a cloud deck that clears before it gets to Class E, say it clears at 200AGL and the ClassE starts as 1200'AGL. You know this because you saw it from the mountain road above the airport on the way in (or have a pirep), somehow you know. You could legally take off, climb in the clouds in Class G and get above the deck and be legal. Not saying its wise, but it could be legal. Ive seen conditions like that, valley fog that is burning off and clear as a bell above. Pilots waiting for it to clear enough to take off.
Do a google for "valley fog". Then click on images.
Do a google for "valley fog". Then click on images.
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