The Special Case of Airspace

Last week we discussed where Class E (controlled airspace) reached the surface, where it met Class G (uncontrolled airspace) and associated VFR minimums… so, why should a cautious VFR pilot care?

Take a gander at figure 1, below. The airspace around Somerset, Kentucky is an example of a situation where Class E airspace touches the ground for a good reason — to protect IFR pilots on an instrument approach. But if the visibility drops to less than three miles, VFR pilots cannot fly in Class E airspace, so how could a VFR pilot trapped in deteriorating weather land at Somerset and places like it with reduced visibility — without declaring an emergency? Fortunately, there’s a rule especially for this kind of situation…


For every good rule, there is an exception. Enter: ‘The Special VFR clearance.’SCUD-RUNNING MADE LEGAL
Look at the diagram of the airspace at Somerset in Figure 2 below. If you were restricted to VFR flight and the visibility was 2 miles, for example, you could only fly where 2 miles was legal. In uncontrolled — Class G airspace — during the daytime, you only need 1 mile visibility. So, if you have 2 miles and are flying VFR you can fly in Class G, but not Class E. Figure 2 shows that there is some low-altitude Class G airspace, but flying all the way to Somerset, would not be possible, because Class E touches the ground at Somerset. There are many airports that you can get to by flying under Class E and remaining in Class G — Somerset isn’t one of them. At Somerset, when the visibility is below 3 miles, a barrier exists to stop VFR traffic. But…

The Special VFR clearance is, as the name implies, a special exception to the 3 mile visibility rule that can be used by VFR pilots at locations where the Class E — controlled airspace — touches the surface. The Special VFR clearance, when granted, allows the VFR pilot to venture into the Class E airspace, despite the fact that the visibility is not above 3 miles. In our example at Somerset, a pilot can use it to fly across the magenta dashed line and straight to the airport. Of course, the reason for having Class E — controlled airspace — drop to the surface in the first place is to avoid mid-air collisions between low altitude VFR traffic and IFR traffic flying an instrument approach. So how does ATC keep airplanes apart when a Special VFR is granted? ATC will only grant a Special VFR clearance, when there are no IFR airplanes around. You can’t hit something that isn’t there!

Important: If any IFR traffic is in the area, either inbound and preparing for an approach, or taxiing out for an IFR departure, your Special VFR will be denied. If you’re VFR in the scud, when that happens, you’ve just sentenced yourself to wandering around at low altitude in poor visibility in Class G — uncontrolled airspace — until the IFR traffic clears the area. Some airports are so busy with IFR traffic that there is never a window between IFR arrivals and/or departures. Such airports never allow Special VFRs and may or may not tell you so with the notation ‘No Sp VFR’ in the Airport Facilities Directory.

You can only get a Special VFR clearance by talking to someone who has knowledge of the incoming or departing IFR traffic — the best person to call would be a controller at the nearest Air Route Traffic Control Center (ARTCC). These folks will know about all the IFR traffic, but contacting them might be impossible. Remember, if you need a Special VFR clearance, that generally means you are trapped down low in uncontrolled, Class G airspace. Consider the limitations of your line-of-sight VHF transceiver. Translation: Good luck. Besides, you would have to already know the areas ARTCC frequency, because they are not printed on sectionals.

If you can’t talk with ARTCC directly you must talk to them indirectly.

Look again at Figure 1. Notice that Somerset has a Remote Communications Outlet (RCO) — this is indicated by the blue box located northwest of the Somerset airport. It says ‘Somerset RCO‘ inside the box and lists the frequency of 122.55 above the box. The box has a bracket underneath that says ‘Louisville.’ That box means that Somerset has a radio antenna that is linked to a telephone line and the telephone line is directly connected to the Louisville Flight Service Station. A pilot in the Somerset area, especially a pilot flying low in Class G airspace, could never transmit the hundred miles to Louisville. The terrain and the curvature of the Earth would block the transmission. When the pilot uses 122.55, the signal is received at the Somerset antenna and then by telephone wires to the Flight Service Station in Louisville.

The RCO is a link that extends the reach of the FSS to areas too far for direct radio transmission.

The pilot in need of a Special VFR can call the FSS using the RCO as a link. The FSS briefer, does not have the ability to keep up with IFR traffic, so they will have to call the nearest ARTCC and get the information for you. In this way the FSS becomes the ‘middle-man‘ in a communication chain. The ARTCC will determine if a Special VFR is possible and grant or deny a Special VFR clearance. The ARTCC tells the FSS about the clearance on the telephone, and then the FSS calls the pilot back on the radio with the news.

The Special VFR clearance might sound something like this: ‘ATC clears N1234A into Class E airspace under Special VFR rules, below 2,000 feet, direct to the Somerset airport.’ When the Special VFR clearance is granted the pilot should act quickly. Fly carefully and expeditiously to the airport, and get on the ground.

It is important to note that a Special VFR can only be granted if and when the pilot asks for it by name. A controller cannot legally suggest a Special VFR to a pilot — it must be the other way around. The request should sound something like this: ‘Somerset Tower, Cessna N1234, ten south, inbound. Request Special VFR for landing.’

Inside Experience: I did hear a sharp controller once save a lost student pilot by stretching the ‘no suggesting‘ rules to the limit. I was inbound to the airport flying IFR in the clouds when, on the tower frequency, I heard, ‘Kinston Tower, this is NXXXX, I would like to land.’ The tower came back with ‘Kinston is IFR, stay clear of the airspace, what are your intentions?’ This is where the VFR pilot should have asked for a Special VFR, but it was clear by his voice he was nervous and probably did not know what Special VFR was, let alone be able to say it under pressure. Several anxious minutes went by. I was lining up for the ILS and did not really want to start a decent not knowing where the VFR pilot was. The controller sensed the situation reaching a critical point and then did a smart (and probably courageous) thing. He said to the nervous VFR pilot, ‘A few minutes ago another pilot asked for a Special VFR — what are your intentions?’ Now, that student pilot never actually said the words Special and VFR together, but on his next jumbled transmission he did have those words in the same sentence, so the controller accepted that as a Special VFR request and granted him entry and a landing clearance. I completed my ILS approach and landed about three minutes later — the story ended happily (except for concerns about what the student was doing flying on a day like that… and where was his instructor!).

BOTTOM LINE: Being familiar with the purpose and method of the Special VFR as described in the Airman’s Information Manual is just another tool in your kit. I don’t recommend that you make a habit of using it, but you need to know how to use it, because it may help you out of a jam someday. Remember, a Special VFR clearance is only possible where controlled airspace (Class E, D, C, or B) touches the surface and when visibility is less that 3 miles.

Editor’s Note: Since 1995, Paul A. Craig has conducted innovative seminars on the airspace system at college and universities, Pilot Proficiency programs, and Flight Instructor Refresher Clinics across the country.