David Zhong Posted August 14, 2009 at 08:20 AM Posted August 14, 2009 at 08:20 AM Question: Why are IFR clearances required in the United States? In Australia (and I believe, the ICAO standard), a clearance is not required for IFR aircraft unless entering Cl[Mod - Happy Thoughts] A, C, D or E airspace (no Cl[Mod - Happy Thoughts] B is Australia). In Australia, IFR aircraft which are outside controlled airspace will be in contact with the controller, but not actually under the control of that controller. In Cl[Mod - Happy Thoughts] G, no separation is provided, except that traffic information is p[Mod - Happy Thoughts]ed to IFR aircraft regarding other aircraft that ATC knows about (incl. other IFR aircraft). David Zhong Link to comment Share on other sites More sharing options...
Trent Hopkinson Posted August 14, 2009 at 12:54 PM Posted August 14, 2009 at 12:54 PM Cl[Mod - Happy Thoughts] G: IFR and VFR flights are permitted and do not require an airways clearance. IFR flights must communicate with air traffic control and receive traffic information on other IFR flights and a flight information service. VFR flights receive a flight information service if requested. note the term "Must" IFR flights must communicate with air traffic control and receive traffic information on other IFR flights and a flight information service. from: http://www.airservicesaustralia.com/aboutus/howatcworks/ourairspace.asp By definition, you cannot be given a full control service below the Controlled Airspace (CLL) However you must still communicate with ATC with your departure reports "XXX Centre and all stations *airfield* *Aircraft type and callsign* taxis runway xx for *Destination airfield*" You will even be given a discreet squawk code (or be squawking 2000 in some circomestances, particularly non-radar areas) This gets the ball rolling. You can even do IFR pickups, such as when you are OCTA and want to climb into the CTA. But why does USA control outside of controlled airspace? they probably don't. Just, there probably isn't all that much of it. Even the majority of their small airfields are still Cl[Mod - Happy Thoughts] D. Not being entirely sure of the USA rules, I would still be surprised if actual Control service was available Outside Controlled Airspace, as that would be a bizzare contradiction in terms. Perhaps it is just the lack of large areas of Uncontrolled airspace, and that which is uncontrolled, is more like the Victor 1 (see http://www.airservices.gov.au/publications/current/ersa/FAC_YSSY_4-Jun-2009.pdf for details on Victor 1) than things like Bathurst etc. Of course the actual phraseology of such things is going to be different like everything else in the USA. Trent Hopkinson YMML. www.youtube.com/musicalaviator WorldFlight 2002,2008,2009, 2011, 2012, 2013 & 2015 Link to comment Share on other sites More sharing options...
Keith Smith Posted August 14, 2009 at 03:46 PM Posted August 14, 2009 at 03:46 PM David, It would help to have some clarification of your question, but I'll do my best... In the USA, aircraft cannot operate under IFR in controlled airspace unless they have a clearance. A clearance is NOT required to operate IFR in uncontrolled airspace. Trent, 'most small airfields' are actually in Cl[Mod - Happy Thoughts] G airspace (uncontrolled) at their surface with controlled airspace (Cl[Mod - Happy Thoughts] E) starting at 700 or 1200agl. Some non-towered fields are Cl[Mod - Happy Thoughts] E (controlled) down to the surface. After this, you hit the realms of towered airports, which are Cl[Mod - Happy Thoughts] D, C, or B. Does this mean you can depart IFR from 'most' airports in the USA without a clearance? Not really. In no time at all, in MOST parts of the country, you'll hit controlled airspace (Cl[Mod - Happy Thoughts] E), at which point you must have a clearance before you can operate IFR. Link to comment Share on other sites More sharing options...
David Zhong Posted August 15, 2009 at 04:32 AM Author Posted August 15, 2009 at 04:32 AM However, in the US, pilots request "IFR clearance", whereas in other parts of the world pilots ask for "airways clearance", which is essentially controlled airspace clearance. David Zhong Link to comment Share on other sites More sharing options...
William Lewis Posted August 21, 2009 at 09:40 PM Posted August 21, 2009 at 09:40 PM Lets start out with the word "Clearacne" keep in mind this is the US 7110.65 AIR TRAFFIC CLEARANCE- An authorization by air traffic control for the purpose of preventing collision between known aircraft, for an aircraft to proceed under specified traffic conditions within controlled airspace. The pilot-in-command of an aircraft may not deviate from the provisions of a visual flight rules (VFR) or instrument flight rules (IFR) air traffic clearance except in an emergency or unless an amended clearance has been obtained. Additionally, the pilot may request a different clearance from that which has been issued by air traffic control (ATC) if information available to the pilot makes another course of action more practicable or if aircraft equipment limitations or company procedures forbid compliance with the clearance issued. Pilots may also request clarification or amendment, as appropriate, any time a clearance is not fully understood, or considered unacceptable because of safety of flight. Controllers should, in such instances and to the extent of operational practicality and safety, honor the pilot's request. 14 CFR Part 91.3(a) states: "The pilot in command of an aircraft is directly responsible for, and is the final authority as to, the operation of that aircraft." THE PILOT IS RESPONSIBLE TO REQUEST AN AMENDED CLEARANCE if ATC issues a clearance that would cause a pilot to deviate from a rule or regulation, or in the pilot's opinion, would place the aircraft in jeopardy. Simply enough that when an Air traffic controller tells you that you are Cleared that means he is providing your separation. An aircraft flies IFR to have ATC provide separation services to that aircraft. Were as a VFR aircraft are responsible for their own separation. With out a clearance, it is your job as a pilot to maintain your own visual separation which means you are VFR. With a Clearance ATC is providing separation for you so you become IFR. This is just basic and there are many ways to twist this around but one thing you may keep in mind. ATC should only clear a VFR aircraft for two things: 1. Cleared to Land/Takeoff (ATC will provided your separation while on the runway and ensure that you will not hit anyone else). 2. Cleared in/out/through a cl[Mod - Happy Thoughts] Bravo airspace (ATC controllers must provide separation services to all aircraft inside the cl[Mod - Happy Thoughts] bravo so VFR must receive a clearance prior to operating inside the confines of the Bravo). The above pertains to United States Link to comment Share on other sites More sharing options...
David Zhong Posted August 22, 2009 at 06:29 AM Author Posted August 22, 2009 at 06:29 AM I think I understand it now. While Australia has predominantly cl[Mod - Happy Thoughts] G airspace, most of US airspace is cl[Mod - Happy Thoughts] E, thus "IFR Clearances". Thanks everyone for helping me understand this. David Zhong Link to comment Share on other sites More sharing options...
Mike Cassel 849958 Posted August 22, 2009 at 10:45 AM Posted August 22, 2009 at 10:45 AM I think I understand it now. While Australia has predominantly cl[Mod - Happy Thoughts] G airspace, most of US airspace is cl[Mod - Happy Thoughts] E, thus "IFR Clearances". Thanks everyone for helping me understand this. That's exactly right. Cl[Mod - Happy Thoughts] G airspace in the United States is limited, and Cl[Mod - Happy Thoughts] G above 1200 AGL is rather rare. In the US, you don't need an IFR clearance to operate IFR in Cl[Mod - Happy Thoughts] G airspace, but pilots ask for "IFR clearance" since pilots will nearly always be in controlled airspace shortly after departure at the latest. Link to comment Share on other sites More sharing options...
William Lewis Posted August 22, 2009 at 11:17 AM Posted August 22, 2009 at 11:17 AM I will have to double check myself but I don't think you are able to fly IFR in Cl[Mod - Happy Thoughts] Golf. I have a feeling i may be wrong in this case and would like to see the docomeentation to prove it but here is my case. 1. The purpose of IFR is the ability to fly and aircraft when you can see what is around you. 2. When you cant see what is around you you can not provide your own separation so you leave it up to ATC to provide your separation. 3. ATC is not allowed to control Cl[Mod - Happy Thoughts] Golf airspace so they are not able to provide you with separations services. 4. Since they cannot control Cl[Mod - Happy Thoughts] Golf airspace they can not provide a clearance to fly though cl[Mod - Happy Thoughts] golf airspace. 5. A clearance is required to operate as IFR and therefore cannot operate as IFR. As soon as you depart or just before you arrive you may be IFR while you are in the Cl[Mod - Happy Thoughts] Echo airspace, but once you enter the Cl[Mod - Happy Thoughts] Golf you are responsible for your own separation. I know why i am doubting this and i have my own argument to debate against this but ill wait to see what everyone else has to say The above pertains to United States Link to comment Share on other sites More sharing options...
Mike Cassel 849958 Posted August 22, 2009 at 06:41 PM Posted August 22, 2009 at 06:41 PM Will, See AIM 3-3-3. 3-3-3 refers to IFR flight in Cl[Mod - Happy Thoughts] G airspace. See also FAR 91.179, referring to cruise altitudes in Cl[Mod - Happy Thoughts] G airspace for IFR, FAR 91.126, referring to proper lost communications procedures if under IFR at a Cl[Mod - Happy Thoughts] G airport, compare FAR 91.173, which requires clearance and a flightplan only in controlled airspace. Link to comment Share on other sites More sharing options...
David Zhong Posted August 23, 2009 at 03:17 AM Author Posted August 23, 2009 at 03:17 AM In Australian Cl[Mod - Happy Thoughts] G: - IFR flights receive information about other IFR flights from ATC. IFR aircraft can then coordinate with each other to self-separate, but can also receive advice from ATC. - VFR flights are solely responsible for separating themselves from IFR flights. However, where there are VFR flights, there will be VMC, therefore the IFR flight should also be able to visually sight the VFR flight. And no, a clearance is not required to operate in Cl[Mod - Happy Thoughts] G, but two-way communications with ATC is required. In areas with radar coverage, you will also be issued a transponder code. However, I am still confused as to why RPT flights ask for "IFR clearance" in cl[Mod - Happy Thoughts] A/B/C/D airspace, whereas the rest of the world would call it an "airways clearance" (a common clearance for IFR and VFR flights to operate in controlled airspace). David Zhong Link to comment Share on other sites More sharing options...
Brad Littlejohn Posted August 23, 2009 at 07:26 AM Posted August 23, 2009 at 07:26 AM In Australian Cl[Mod - Happy Thoughts] G: - IFR flights receive information about other IFR flights from ATC. IFR aircraft can then coordinate with each other to self-separate, but can also receive advice from ATC. - VFR flights are solely responsible for separating themselves from IFR flights. However, where there are VFR flights, there will be VMC, therefore the IFR flight should also be able to visually sight the VFR flight. And no, a clearance is not required to operate in Cl[Mod - Happy Thoughts] G, but two-way communications with ATC is required. In areas with radar coverage, you will also be issued a transponder code. However, I am still confused as to why RPT flights ask for "IFR clearance" in cl[Mod - Happy Thoughts] A/B/C/D airspace, whereas the rest of the world would call it an "airways clearance" (a common clearance for IFR and VFR flights to operate in controlled airspace). Part of this is because of how each airspace is set up. In Cl[Mod - Happy Thoughts] A airspace (FL180 and above), you must file and fly IFR unless you are requesting VFR-on-top (which is done on an IFR flight plan anyway). For the others, and let's use Cl[Mod - Happy Thoughts] B as an example, you could be underneath the floor of said airspace, or even above it (for this example, I'll only deal with below, as to get above it, you'd have to have flown through it, requiring clearance into and out of it). If below it, you could depart a field VFR, stay below the floor of Cl[Mod - Happy Thoughts] B airspace, and never have to talk to ATC. Same with Cl[Mod - Happy Thoughts] C airspace. So let's say you're at KSMO, and you are wanting to depart VFR to the west. You can simply call up for VFR departure to the west. looking at the sectional and TAC, if you are going to stay under the Cl[Mod - Happy Thoughts] B floor for that area (5000ft MSL), you won't be entering Cl[Mod - Happy Thoughts] B airspace requiring ATC. You depart to the west, and after you leave KSMO's space, "frequency change approved", and you're on your way. Here, IFR clearance means that you will be in ATC's control throughout the course of your flight from takeoff to landing ([Mod - Happy Thoughts]uming your destination has a controlled tower), or until ATC cuts you loose. BL. Brad Littlejohn ZLA Senior Controller Link to comment Share on other sites More sharing options...
Jason Baxter 920557 Posted August 23, 2009 at 07:38 AM Posted August 23, 2009 at 07:38 AM 7-1-1 Cl[Mod - Happy Thoughts] A Airspace Restrictions Do not apply visual separation or issue VFR or "VFR on top" clearances in Cl[Mod - Happy Thoughts] A airspace. Link to comment Share on other sites More sharing options...
Brad Littlejohn Posted August 23, 2009 at 01:13 PM Posted August 23, 2009 at 01:13 PM 7-1-1 Cl[Mod - Happy Thoughts] A Airspace Restrictions Do not apply visual separation or issue VFR or "VFR on top" clearances in Cl[Mod - Happy Thoughts] A airspace. Good catch, JB. I see where it could be mistaken that you could use VFR on top in Cl[Mod - Happy Thoughts] A, when that definitely isn't the case. (it's too bloody early in the morning.) BL. Brad Littlejohn ZLA Senior Controller Link to comment Share on other sites More sharing options...
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