More Than One Way

Snagging an IFR clearance at a nontowered airport isn't a big deal especially when you know the variety of ways to make it happenPopUp Clearances


In aviation as in life, there are often multiple ways to accomplish a single task. I learned that lesson early in my training as a radar approach controller.

When I sequence aircraft to final, I can use headings, vectors, speed, or any combination of the three to achieve the required spacing. Is a VFR aircraft calling me for flight following? I can identify it using its reported location, by giving it a turn, or—most commonly—by assigning it a squawk code. Specific situations dictate the methods.

So it goes with IFR clearances from nontowered airports. The United States has nearly 20,000 airports. Only a few have control towers operating 24/7. To provide IFR clearances from the thousands of remaining fields, the FAA offers multiple options.

Airport variety demands flexibility. Some airports have only one method. Others have multiple types. All paths lead to the same result: an air traffic controller issues an IFR clearance to a pilot.

The process to get that clearance may be daunting or confusing if you’re used to the convenience of a control tower. In reality, it’s not that complicated. Each method just requires some patience and a basic understanding of the process and requirements.

Cracking a Window
Before we go on to the different methods, let’s talk about their common elements. All IFR clearances—tower or no tower—contain the same core information. You probably learned the acronym CRAFT for Clearance limit, Routing, initial and final Altitude, departure Frequency, and Transponder squawk code. This format is universal. Uncontrolled field operations just build on that.

The next three elements are common to any nontowered field clearance. First is a question you’ll be asked by any controller issuing you a clearance from an uncontrolled field: When will you be ready for takeoff? That ties in with the last two bits: a release time and a “void if not off by” time, or VIFNO.

Those three are a big deal. Why? ATC can’t legally allow more than one IFR aircraft at a time in or out of an uncontrolled airport. (Check out my previous article, “No Tower, No Problem,” in June 2013 for more details on this.) To accurately gauge where you fit in with other arrivals and departures, they need to know when you’ll be ready for takeoff.

Exercise good judgment here. Are you sitting in the FBO lounge and waiting on your passengers to arrive? You may want to get your clearance later. Since you have no real estimate, you’ll just be instructed to “hold for release” anyway.

The option we recommend is to call for your clearance on taxi. You know how long your engine runup takes and how long it’ll take to taxi to the runway. Add a couple extra minutes for cushioning, and you’ve got a good estimate.
Once you pass along your estimated departure time, you’ll get a release time, a VIFNO, and a time check. “N3AB released for departure at 1410. Clearance void if not off by 1415. Time now 1355 Zulu.” Within those times, the airport is effectively shut down to other IFR traffic until you depart or the window closes. If ATC doesn’t issue a VIFNO, the clearance automatically voids in 30 minutes.

This release window is serious business. If you depart even one minute before or after that release window, your IFR clearance isn’t valid and you violate CFR 91.173: “No person may operate an aircraft in controlled airspace under IFR unless that person has: (a) Filed an IFR flight plan; and (b) Received an appropriate ATC clearance.”

Pilot deviations are no fun for anyone; just call for an extension if you need one.

Relay Race
Let’s actually go get an IFR clearance now. One universal clearance delivery method is a telephone call to Flight Service. All you need is a phone, a reliable clock, and your departure time. There are no radio transmitters involved, although modern headsets and audio panels often include a capability to make the call from the plane while holding short.

Is the telephone number 1-888-766-8267 familiar? If not, take out your cell phone and program that into your contacts right now. I’ll wait.

In the name field, enter “National Clearance Delivery number.” That’s a direct line to Lockheed Martin Flight Service from anywhere in the country. Some airports may have specific FSS numbers for faster service, but that national number works everywhere.

The Flight Service specialist who answers your call will need your departure and destination airport identifiers. “Our setup makes it easy,” said a Flight Service specialist I interviewed. “After we verify that your call sign has an IFR flight plan in the system, we’ll look up your departure airport. The system will tell us the name and number for the responsible sector of the appropriate radar facility.”

The radar controller will take the FSS call either via dedicated ATC landlines or on a regular telephone, depending on the facility’s equipment. “Richmond Flight Service here,” FSS will say, “looking for a clearance for N4GP off of Home Airport to County Airport.”

The controller will locate your IFR flight plan and gauge the current traffic. If the situation looks good, he’ll issue the FSS specialist your IFR clearance, a release time plus VIFNO—or a “hold for release” if he’s got conflicting traffic—a time check, and any other departure instructions or headings.

FSS then relays that information to you. They’ll preface it with “ATC clears…” as an indicator that FSS is just the middle man giving you the clearance on behalf of ATC. As you note the release time, make sure your watch, phone clock, or panel clock match the time check given by ATC. Timing is everything.

Remote Communications
Let’s move past a basic phone call into the world of radio communications.
There are two types of radio-based ground stations that enable you to talk directly with Flight Service: the Remote Communications Outlet (RCO) and the Ground Communications Outlet (GCO). I’ve noticed some pilots—and even the FAA at times—use these terms interchangeably, but they operate in quite different ways.

An RCO is a radio ground station set to a dedicated Flight Service frequency. There are many classes of them, some used for air-to-ground communications with FSS, such as for the submission of PIREPs or opening of VFR flight plans. The type we’re dealing with for clearances are class O, which are designated for ground-to-ground comms only, such as closing flight plans and—no surprise here—getting IFR clearances.

If an uncontrolled airport has an RCO available, the frequency and the related FSS are listed in that airport’s Airport and Facility Directory “Airport Communications” section. An example can be found by looking up Lovelock, Nevada’s Derby Field Airport (KLOL). It lists “LOVELOCK RCO 122.4 (RENO RADIO).”

Simply dial in the listed frequency and reach out to the FSS name listed in parentheses. “Reno Radio, N4GP at Lovelock Airport, requesting clearance.” Tip for sounding like you know what you’re doing: Don’t just call the FSS, but call the FSS and specify the outlet through which you’re calling them. That one Flight Service specialist might literally have dozens of outlets and if you don’t specify which one you’re using, s/he will have to reply on all of them.

Once the specialist comes on frequency, the process is similar to a standard telephone relay. They’ll verify your flight plan, get your IFR clearance and release from the appropriate ATC radar controller, and pass on your clearance with the aforementioned “ATC clears…” prefix.

Clickety Click Click Click
A Ground Communication Outlet (GCO) uses different technology to achieve a similar result as an RCO. This hybrid design combines a radio with a telephone connection. It’s controlled by a mic-click system similar to that which operates pilot-controlled lighting.

While RCOs are limited to FSS, GCOs may connect you to either FSS or—when available—directly to the airport’s overlying ATC radar facility. You determine who you call by selecting the GCO’s frequency, then clicking your mic four times to reach ATC or six times for FSS. Upon receiving the specified number of clicks, the GCO will literally phone the desired facility, ring tone and everything.

GCO information is typically found in the A/FD under “Airport Communications” but, inexplicably, it can also appear in the airport’s “Additional Remarks” section. So, look carefully.

If you’re calling Flight Service via GCO, the process is essentially the same as a standard telephone call, except it’s simplex—you can talk or you can listen, but you can’t do both at the same time.

Before we move on, here’s a little heads-up about GCOs: the system will close the telephone connection if it doesn’t hear anything on the frequency for a while. If FSS or ATC have to put you on hold for a bit to work on your flight plan or deal with other aircraft, click the mic once every thirty seconds or so to keep your connection open.

Straight to the Source
A cumbersome game of password between Flight Service and ATC is sometimes the only way to get a clearance. But, at some nontowered airports, there are two ways to cut out the middle man and talk directly to the controller.

One way is via those GCOs, where clicking four times calls ATC. The controller will answer with the facility name or sector like for a regular phone call. That’s your cue to request your clearance.

The second is like an RCO, but goes directly to ATC. A good rule of thumb when contacting ATC this way is to say you’re on the ground. We radar guys can have dozens of frequencies to monitor and like the Flight Service specialist, it’s not easy to tell who’s calling. If you call without saying you’re on the ground, we usually assume you’re airborne somewhere. Make that distinction to reduce confusion. It’s as easy as, “Huntsville Approach, N4GP on the ground at Madison County, requesting clearance to KJKA.”

The clearance delivery frequency has the obvious efficiency advantage that you speak directly with the controller who’s both issuing your IFR clearance and working you once you’re airborne. Both pilot and controller can instantly communicate traffic, clearance, weather, and other important information. Need a couple of extra minutes on your release window? Tell the controller directly. No Flight Service relay required. Does ATC need to amend your departure instructions or clearance? They can reach you before you depart. (You’re monitoring, right?)

No matter the method, the end result is the same: you get an IFR clearance and departure instructions and a release window. Just figure out which is the best method available and walk that path.

When your window opens, announce your departure intentions via the airport’s CTAF and takeoff in compliance with any airport-specific procedures—such as Obstacle Departure Procedures—as specified in AIM 5-2-8. Once safely clear of the traffic pattern, contact ATC on the assigned departure frequency. ATC will be protecting the airspace for your departure and send you on your way as soon as they radar-identify you.

Are nontowered ops more work than flying out of a towered airport? Sure, a bit. At the same time, getting the hang of it puts literally thousands of new airports within your IFR-ready reach.

Tarrance Kramer prefers to keep those release windows open longer in the winter. It keeps the A/C bill down.

At my radar facility, we oversee plenty of nontowered fields and—as a result—issue plenty of popup IFR clearances.

What’s an IFR popup? When an aircraft departs an airport VFR, calls ATC in the air, and requests an IFR clearance from his departure airport, his present position, or a fix along the way. It bypasses the whole release-window thing.

After we locate the pilot’s IFR flight plan, we then ensure that he’s at a safe IFR altitude by verifying he’s above our minimum vectoring altitude (MVA) or asking him “Can you maintain your own terrain and obstruction clearance?” from his present altitude up to our MVA. Then we ensure he’s clear of other IFR traffic, issue him a standard IFR clearance, and he’s on his way.

Things can get complicated in bad weather. Remember: you are VFR until ATC gives you that IFR clearance. Until then you are required to maintain your own traffic, terrain, and weather separation. An instrument rating doesn’t mean you can go IMC on a whim and punch through an overcast to top the MVA.

So, if you say you can’t maintain your own obstruction clearance, what can ATC do? Not much. All I can say is, “Maintain VFR and say intentions.” It sucks, but that’s the reality. I can’t legally give you an IFR clearance below my MVA.

When the weather’s marginal and you have even the slightest doubt about finding a hole into the wild blue yonder, just get your clearance on the ground. It might take a bit longer, but it’ll be a more controlled process, and you don’t risk getting caught between a cloud and a very rocky hard place. —TK


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