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Obstruction Clearance

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minitour said:
...but why would you want to go to/from that airport without getting a flight plan on file and a clearance?

There is no such thing as an IFR clearence in Class G airspace, it doesn't exist. ATC has neither the responsibility nor authority to seperate IFR traffic in Class G airspace.

As for a flight plan on file, can you explain to me what you thnk that will do for you ? (other than activate SAR if you don't show up when you're supposed to)
 
Gutenberg said:
Be able to climb 200' per nautical mile, aka a diverse departure, or comply with any published obstacle departure in the front of the approach pubs. If you can get to the MEA, MOCA, or OROCA, you will already be above the MVA. The MVA will be the lowest of all of these.

If the publication says "climb on runway heading," be careful, the TERPsters don't factor in wind.

Be careful with this, this is only for airposrts which have been evaluated for a departure. If there is no IAP, the airport probably hasn't been surveyed for a departure.
 
avbug said:
Quote:XYZ maintain own obstruction clearance to 2500 feet, cleared direct, sqauwk XXXX.Basically, it meant we were cleared direct and given an IFR clearance once we reached 2500 feet. UnquoteNo, you already have your IFR clearance in this case. You're cleared IFR, but must maintain your own terrain separation to 2,500'. You're making the assumption, with the clearance as you've given it, that you're not cleared IFR until reaching 2,500', but that's not what you posted. In the case of what you posted, you're cleared IFR, direct destination, but must maintain own terrain separation to 2,500'. In this case, you do not need to remain visual; you can enter the cloud, so long as you can ensure terrain separation by any number of means. All this indicates is that you're the one who is responsible. Clearly, ATC has told you ATC will not be responsible. Never the less, you are cleared IFR, destination direct.
Seems the board still needs some tweaking. Most of my "buttons" don't work.

Actually AB, it does mean I have to reach 2500' before I have my ATC clearane, just like a clearanc limit. Since ATC cannot give you a "pop up" clearance at an altitude below their MVA for that area. The use of "maintain your own obstruction clearance" was more of friendly "hey we know your probably in some low weather, climb up to this altitude and we can get you in the system". It all sounds kinda shady but it really works out well if the weather comes in on you.

Keep in mind this isn't something that is practiced every day and probably varies in its use from control facility to control facility and the only exposure I ever had with it was at my home airport. And, the way we used it was, maintain basic VFR until the prescribed altitude and then you've got your clearance.

I should have clarified in my earlier post that the MVA for the area was 2500 feet. sorry for the confusion.
 
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A Squared said:
There is no such thing as an IFR clearence in Class G airspace, it doesn't exist. ATC has neither the responsibility nor authority to seperate IFR traffic in Class G airspace.

As for a flight plan on file, can you explain to me what you thnk that will do for you ? (other than activate SAR if you don't show up when you're supposed to)

So you couldn't file from ABC airport Direct DEF airport (using GPS) and have the flight be entirely in class G airspace and still get your clearance, etc?

-mini
 
DC8 Flyer said:
Actually AB, it does mean I have to reach 2500' before I have my ATC clearane, just like a clearanc limit. Since ATC cannot give you a "pop up" clearance at an altitude below their MVA for that area. The use of "maintain your own obstruction clearance" was more of friendly "hey we know your probably in some low weather, climb up to this altitude and we can get you in the system". It all sounds kinda shady but it really works out well if the weather comes in on you.

Keep in mind this isn't something that is practiced every day and probably varies in its use from control facility to control facility and the only exposure I ever had with it was at my home airport. And, the way we used it was, maintain basic VFR until the prescribed altitude and then you've got your clearance.

I should have clarified in my earlier post that the MVA for the area was 2500 feet. sorry for the confusion.
Sorry, I go with avbug on this one. I routinely operate part 121 out of an non-towered airport (but controlled airspace) and receive a similar clearance below MVA. We are IFR once we receive such a clearance, but the controller is not guaranteeing obstruction clearance. He is guaranteeing seperation from IFR traffic. The whole class G issue is separate. Typically, an IFR clearance out of an "uncontrolled" airport will sound more like "upon entering controlled airspace, cleared to XYZ via as filed etc etc" The purpose of an IFR clearance is to provide separation from other IFR traffic. Terrain clearance is provided by published procedures and routes, or, in radar contact, minimum vectoring altitudes. If you received your clearance on the ground, the phrase "maintain your own terrain and obstruction clearance" is unnecessary since it is presumed you are complying with IFR departure procedures immediately upon liftoff. If you pick up the IFR aloft, but below MVA, then you are VFR when you call... hence you cannot be presumed to be complying with published IFR procedures. You could be anywhere since you are just using visual seperation from terrain. Hence the controller must remind you that your "pop-up" IFR clearance is not providing terrain seperation. You must provide your own, either by maintaining visual from the terrain or compying with a published procedure (or, in many instances, simplying climbing 200'/nm as somebody mentioned). However, you are IFR as soon as you hear "cleared via....". You can enter the clouds if you can legally and safely maintain terrain and obstruction clearance.
 
minitour said:
So you couldn't file from ABC airport Direct DEF airport (using GPS) and have the flight be entirely in class G airspace and still get your clearance, etc?

No, there is no such thing as a clearance in Class G Airspace. A clearence is an ATC thing, and ATC has no authority, responsiblity or purpose in Class G airspace.
 
A Squared said:
No, there is no such thing as a clearance in Class G Airspace. A clearence is an ATC thing, and ATC has no authority, responsiblity or purpose in Class G airspace.

hmm...interesting...learn somethin' new every day.

-mini
 
minitour said:
So you couldn't file from ABC airport Direct DEF airport (using GPS) and have the flight be entirely in class G airspace and still get your clearance, etc?

-mini
That is correct. ATC will not give you a clearance in class G airspace. However, the situation you describe is extremely rare in the 48 states. You'd be hard pressed to find an area where you can fly cross-country in IFR in class G airspace (remember that you still have to comply with IFR altitudes and height above terrain). Airways are class E, so you have to avoid them... and forget about shooting an approach. If the airport has an approach, I guarantee you it has controlled airspace above it. But if your flying across northern Alaska or something below 14,500' then you can fly through all the clouds you want. You could also fly transatlantic down low without talking to anybody (until you reach the ADIZ, then you better start talking).
 
Apparently I can't use the quote features, or any of the other toolbar items...I don't know why. However...Quote:""Actually AB, it does mean I have to reach 2500' before I have my ATC clearane, just like a clearanc limit. Since ATC cannot give you a "pop up" clearance at an altitude below their MVA for that area. ''' End QuoteThis is incorrect. ATC can give you the clearance on the ground, below the MVA, below radar coverage, and give you a clearance void time.The clearance as you've provided it is a clearance to the destination, direct. That's why you said, cleared direct destination. That you were told to maintain own terrain until 2,500 doesn't negate the fact that you've been cleared. If you weren't cleared, you would have been told to expect a clearance upon reaching 2,500. Instead, the clearance you provided, clearly stated that the flight has been cleared...you've already received the clearance. There's nothing in the wording you provided that would indicate or mean anything else.I've picked up clearances many, many times, out of radar coverage. I'll get a clearance void time, and then check in with ATC in the air. Until I get radar vectors in flight, or am radar identified on part of my cleared routing, I'm responsible for my own terrain separation.The truth is, no matter who identifies what, you're always ultimately responsible. At the end of the day when you're oozing off a rock and slowly freezing to a little red icicle, it's the controller who goes home to feed the dog, and you that becomes dog food. You're always ultimately responsible for your own terrain clearance, no matter what's handed you by ATC.
 
ackattacker said:
Sorry, I go with avbug on this one. I routinely operate part 121 out of an non-towered airport (but controlled airspace) and receive a similar clearance below MVA. We are IFR once we receive such a clearance, but the controller is not guaranteeing obstruction clearance. He is guaranteeing seperation from IFR traffic. The whole class G issue is separate. Typically, an IFR clearance out of an "uncontrolled" airport will sound more like "upon entering controlled airspace, cleared to XYZ via as filed etc etc" The purpose of an IFR clearance is to provide separation from other IFR traffic. Terrain clearance is provided by published procedures and routes, or, in radar contact, minimum vectoring altitudes. If you received your clearance on the ground, the phrase "maintain your own terrain and obstruction clearance" is unnecessary since it is presumed you are complying with IFR departure procedures immediately upon liftoff. If you pick up the IFR aloft, but below MVA, then you are VFR when you call... hence you cannot be presumed to be complying with published IFR procedures. You could be anywhere since you are just using visual seperation from terrain. Hence the controller must remind you that your "pop-up" IFR clearance is not providing terrain seperation. You must provide your own, either by maintaining visual from the terrain or compying with a published procedure (or, in many instances, simplying climbing 200'/nm as somebody mentioned). However, you are IFR as soon as you hear "cleared via....". You can enter the clouds if you can legally and safely maintain terrain and obstruction clearance.


You guys are absolutely right.

http://www.faa.gov/atpubs/

Pub 7110.65

Although nothing in the "clearance" section says you have you IFR clearance before reaching the MVA, MEA, or MIA, I think you can reasonably imply that you do.

Guess my good buddy at RDR has some "splaining" to do!

4-2-8. IFR-VFR AND VFR-IFR FLIGHTS
a. Clear an aircraft planning IFR operations for the initial part of flight and VFR for the latter part to the fix at which the IFR part ends.
b. Treat an aircraft planning VFR for the initial part of flight and IFR for the latter part as a VFR departure. Issue a clearance to this aircraft when it requests IFR clearance approaching the fix where it proposes to start IFR operations. The phraseology CLEARED TO (destination) AIRPORT AS FILED may be used with abbreviated departure clearance procedures.
[SIZE=-2]REFERENCE-
FAAO 7110.65, Abbreviated Departure Clearance, Para 4-3-3.

c. When an aircraft changes from VFR to IFR, the controller shall assign a beacon code to Mode-C equipped aircraft that will allow MSAW alarms.
d. When a VFR aircraft, operating below the minimum altitude for IFR operations, requests an IFR clearance and you are aware that the pilot is unable to climb in VFR conditions to the minimum IFR altitude:​
1. Before issuing a clearance, ask if the pilot is able to maintain terrain and obstruction clearance during a climb to the minimum IFR altitude.
NOTE-
Pilots of pop-up aircraft are responsible for terrain and obstacle clearance until reaching minimum instrument altitude (MIA) or minimum en route altitude (MEA). Pilot compliance with an approved FAA procedure or an ATC instruction transfers that responsibility to the FAA; therefore, do not assign (or imply) specific course guidance that will (or could) be in effect below the MIA or MEA.

EXAMPLE-
"November Eight Seven Six, are you able to provide your own terrain and obstruction clearance between your present altitude and six thousand feet?"

2. If the pilot is able to maintain terrain and obstruction separation, issue the appropriate clearance as prescribed in para 4-2-1, Clearance Items, and para 4-5-6, Minimum En Route Altitudes.​
3. If unable to maintain terrain and obstruction separation, instruct the pilot to maintain VFR and to state intentions.
[/SIZE]
 
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