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Keep Out! Part II

Last time, we looked at prohibited and restricted airspace. This time we're going to discuss the other four types in detail (plus an additional thing or two). As you may recall, these remaining types comprise what is known as non-regulatory Special Use Airspace, or SUA.

Last time, we looked at prohibited and restricted airspace. This time we're going to discuss the other four types in detail (plus an additional thing or two). As you may recall, these remaining types comprise what is known as non-regulatory Special Use Airspace, or SUA. They are, in alphabetical order, Alert Areas, Controlled Firing Areas, Military Operations Areas, and Warning Areas. Yes, the term "non-regulatory" does indeed mean that you can theoretically go ahead and crash any of Uncle Sam's parties and no one will come after you, but according to FAA Public Affairs there have been a (very) few violations issued for MOAs, Alert, and Warning Areas. (Just keep in mind that something else that's pointy and fast might be headed your way, too.) When it comes to airspace violations, since General Aviation has begun to look more like General Disorder, at least to the non-flying public, it's a good idea to arm yourself with more information. So, strap in for a few minutes. This won't hurt a bit, and it might occasionally be amusing.

First, some airspace that can really be non-habit forming: Military Operations Areas. As you no doubt noticed from the comparative graphic last time, MOAs are the most prevalent and widespread type of SUA (about 475 in the Continental US, and about 20 more in Alaska). They consist of airspace of defined vertical and lateral limits established for the purpose (as they say) of separating "certain military training activities" from IFR traffic. By definition, a MOA can exist from the surface up to 17,999 feet. (Anything starting at FL 180 up in Class A is known as an "ATCAA" or Air Traffic Control Assigned Airspace.) Whenever one is in use, nonparticipating IFR traffic may be cleared through it, if ATC can provide separation. Military pilots flying within a designated and active MOA are exempt from the provisions of FAR Part 91.303 prohibiting aerobatic flight within Federal airways and Class B, C, D, and E airspace. Pilots operating under VFR should exercise extreme caution while flying within a MOA whenever it's "hot." Contact any FSS within 100 miles of the area in question to get the latest information, and prior to entering an active MOA, pilots should contact the controlling agency for traffic advisories.

They often necessitate aerobatic or abrupt flight maneuvers. First, the speed of military aircraft in a MOA can be anywhere from 250 knots to near Mach 1. Besides possible abrupt changes in speed, they can also quickly change altitude: from only a few hundred feet above ground level to over 18,000 feet MSL, in a matter of seconds. And keep this in mind, also: When military pilots are training in a MOA, they are probably already task-saturated. They're accomplishing many in-flight tasks while attempting to locate and "strike" a target, avoid surface-to-air and/or air-to-air threats such as "attacks" by enemy aircraft, and they are planning their route back to base, keeping track of changing weather, monitoring fuel, armament, and aircraft conditions, speaking on the radio, and watching out for other military, high-speed, hard-to-see, rapidly moving aircraft. (Don't forget that most military aircraft are painted in a low visibility camouflaged paint scheme or color, which only makes them more difficult to see—even for each other—at any time.) Though they are watching for traffic via their on-board radar as well as visually, remember that things are happening at a very rapid pace for the military pilot. Oh and one last thing: if you see one military aircraft, keep looking! It's quite likely that one or more additional aircraft are in the vicinity.

Figure 1 Example: The SUA table on a sectional chart can be a bit confusing for MOAs. For this example (and others) on the Washington sectional, the table says that the given altitudes constitute a floor, and that the MOAs go up to FL 180 "unless otherwise stated." However, two altitudes are given. One might then think the floor must vary within the given range, and the MOA just goes up to FL 180. This one, about 25-n.m. south of Dulles Airport near Quantico, Virginia, is actually three. They're all used intermittently, and the controlling agency is Washington Center. But according to the NACO compiler in Silver Spring, and Quantico ATC, to whom I spoke, the two altitudes are indeed a floor and ceiling; Demo 1 starts at 500 MSL, goes up to 5000 feet, and Demo 3 goes from 5000 to 15,000 MSL. Demo 2 sits atop R-6608 A, B, and C, and goes from 10,000 to 15,000 MSL. (The R-6608 area goes up to 10,000 MSL, is in use from five AM to midnight, as well as other times by NOTAM -- it says to contact FSS 24 hours in advance -- and the controlling agency is the Dulles tower.)

Figure 2 ALERT Areas ... are depicted on aeronautical charts to inform nonparticipating pilots of areas that may contain a high volume of pilot training or an unusual type of aerial activity. The biggest difference between this type and a MOA is that all parties involved must obey "the FARs." Here is what an Alert Area looks like. This one is associated with McGuire AFB in New Jersey. It goes up to and including 4500 MSL from 8 AM to 10 PM, every day. In all, there are about three dozen Alert Areas in the Continental US (and one in Hawaii).

Figure 3 WARNING Areas ... may contain hazards to nonparticipating aircraft in international airspace, though most military operations in these areas are not weapons related. A Warning Area is the least restrictive of the various classifications. Warning Areas are established beyond the three-mile limit. Though the activities conducted within Warning Areas may be as hazardous as those in Restricted Areas, Warning Areas cannot be legally designated as Restricted Areas because they are over international waters. Penetration of Warning Areas during periods of activity may be hazardous to the aircraft and its occupants. Here is a Warning Area, off the Atlantic City coast, belonging to Washington Center. It's in use intermittently, and goes up to (but doesn't include) FL 180. There are about 30 of these off the west coast of the US, 80 off the Atlantic and Gulf coasts, 10 over the waters off Hawaii, and one off the Alaskan coast. Do remember that one fairly common "off-shore" violation is entering an Air Defense Identification Zone (ADIZ), particularly in Florida with GA aircraft returning from the Caribbean.

CONTROLLED FIRING Areas ... contain activities that, if not conducted in a controlled environment, would be hazardous to nonparticipating aircraft. These areas contain operations such as rocket testing, blasting, small arms fire, ordnance or chemical disposal, or artillery firing. They are not marked on charts, but the good news is that the distinguishing feature of the Controlled Firing Area, as compared to other special use airspace, is that its activities are suspended immediately when spotter aircraft, radar, or ground lookout positions indicate an aircraft might be approaching the area. There is no need to chart Controlled Firing Areas since they should not (in theory) create any reason for a nonparticipating aircraft to change its flight path... now for some of that "other stuff":

Figure 4 MILITARY TRAINING Routes ... may be associated with a MOA. (In fact, they're like elongated MOAs.) To be proficient, the military services train in a wide variety of airborne combat methods. One phase of this training involves "low level" tactics. Note that they are indicated on the chart only by their so-called "centerline"; the actual widths of route segments are defined by the military. (They can be up to 55 miles wide, in some parts of the US.) Actually, the term centerline itself is a misnomer, because MTRs are not necessarily symmetrical about that charted line. In all cases, they're wide enough to contain all planned activities, but there is no standard width or height, so there might be one streaking by that's several miles off that thin gray line, which doesn't make them any easier to watch for. The one helpful thing about charted MTRs is that the vast majority are one-way. (If it can be flown the other way, they give it a separate, distinct number.) Below is a picture of a Military Training Route (actually several) from an area about 40-n.m. to the west of Richmond, Virginia. Notice the one-way arrows next to the route designator? When you see the arrows, at least you know that you can concentrate on looking upstream, and you don't really need to look "both ways" before crossing the street. There are over 500 of these, by the way; about half are intended for VFR operations, and the rest for IFR.

Figure 5The routes above 1,500 feet above ground level (AGL) are supposed to be flown, to the maximum extent possible, under IFR. The routes at 1,500 feet AGL and below are generally intended to be flown under Visual Flight Rules (VFR). VFR Military Training Routes have the prefix VR: Operations on these lower routes are conducted in accordance with Visual Flight Rules: flight visibility of 5 miles or more; and not below a ceiling of less than 3,000 feet AGL. One might therefore infer that there would be a much lower likelihood of being dusted off by an F-16 or an A-10 Warthog (which doesn't have radar, by the way) down low, when the weather is scuzzy, but I wouldn't bet on it. MTRs with no segment above 1,500 feet AGL are identified with four digits; e.g., IR1324, VR1017. MTRs that include one or more segments above 1,500 feet AGL are assigned three digit designators; e.g., IR223, VR216. (The best way to recall which is which is to remember that, somewhat perversely, the "higher numbers" signify a lower altitude.) Incidentally, they're divvied up across the US and assigned a number series in hundreds, like the Dewey decimal system. Along these routes, military aircraft can be flown at high speed (up to 650 mph) and low altitude. The VR routes can be right down on the deck, and the IFR route is under ATC guidance. (By the way if I ran NACO, I'd see to it that these MTRs had additional charted data; instead of just "VR1754" I'd like to see "VR1754 7N/10S 100-1300 AGL" You can get all the gory details from the Department of Defense Flight Information Publication (FLIP) Area Planning documents known as AP/1B.)

There are other types of routes that may also be encountered. They are SR (Slow Routes) and LATN (Low Altitude Tactical Navigation Areas). Slow Routes are designed for use at or below 1,500 feet AGL, with airspeeds at or below 250 knots. (There are about 200 of those.) LATN areas are different in that they have specific North, East, South, and West boundaries. LATNs can extend to 1500 AGL, with bases down to 300 feet AGL, and are flown at speeds not to exceed 250 knots. LATN areas are designed to allow crews to practice tactical navigation and flying in areas of simulated and varied threat potential, without being limited to flying a standardized, published route. LATNs are not published on aeronautical charts! Some other military airspace structures include National Security Areas (shown by a broken magenta line, in which avoidance is voluntary, but strongly advised); Cruise Missile Routes (or "unmanned aerospace vehicle routes"; you'd see them near Los Angeles and around Florida); and Aerial Refueling Routes (of which there are about 100).

Bottom Line: Finally, even though instrument-rated pilots are less likely to run afoul of SUA (for the simple reason that you'd be warned in advance if something's hot, or it looks like you're getting off the beaten path), we all must keep track of where we are and where we're going. That includes not only the directions in which we choose to fly, but complying with where ATC says we must fly (or taxi), as well as adherence to assigned altitudes. Not all busts involve airspace, after all; a significant percentage involve deviations from an ATC clearance.

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