Quick answer: A Military Operations Area is not restricted airspace — as a VFR pilot you may legally fly through an active MOA without permission. But legal is not the same as wise, and it is not the same as considerate. Inside a hot MOA, ATC is generally not in continuous two-way contact with the military aircraft working there, fighters are task-saturated and closing at several hundred knots, and an uncoordinated civilian aircraft typically forces controllers to build a protective bubble on the order of 5 miles and 5,000 feet around you — which can shut an exercise down. Make one radio call and that bubble shrinks dramatically.
On The Finer Points, Jason Miller hosted an Office Hours session — a live Q&A he runs weekly inside his ground school app — with two guests who between them cover both sides of the fence: a former air traffic controller who worked MOAs in northern California, and a former F-15E crew member who flew combat air patrols after 9/11. the session is well worth watching in full. Here is what it covers, checked against published FAA guidance.
What a MOA Actually Is
A Military Operations Area is airspace set aside for military training — air combat maneuvering, formation work, and similar activity. The critical distinction is that a MOA is not a restricted area. There is no regulatory requirement to obtain permission before entering, and VFR aircraft may legally transit one whether it is active or not.
That produces two schools of thought among pilots. One holds that if the military wanted the airspace to themselves, they would have had it designated as restricted. Miller’s position is bluntly different — he considers transiting a hot MOA legal but extraordinarily rude, and his reasoning is practical rather than regulatory.
A large exercise may involve dozens of aircraft and personnel, sometimes from several countries, briefed and worked up over months. When an unannounced civilian aircraft appears in the middle of it, the exercise does not continue around you — it stops. Nobody wants to hit you.
His strategic argument is the one worth taking seriously: if it keeps happening, the pressure builds to convert that airspace to restricted, which pilots would like considerably less. Parts of the western United States already offer very limited routing options for exactly that reason.
Why charted MOA altitudes sometimes exceed 18,000 feet
This was the technical highlight of the session, and it catches out experienced pilots. MOAs are established below 18,000 feet — they do not extend into Class A airspace. Yet sectionals routinely show MOAs with published tops well into the flight levels.
The explanation is that a second, separate piece of airspace is stacked on top: ATC Assigned Airspace (ATCAA), scheduled with the FAA, which lets the military reserve a taller block for an exercise. What you are reading on the chart is effectively the MOA plus the ATCAA above it.
This matters most to IFR pilots, and the former controller made the point that it is under-taught. If a block is active up to the mid-twenties, you may be held higher, for longer, than your descent planning assumed — and you generally will not be cleared straight through it. Building that into your expectations is worth more than being surprised at top of descent.
How to Find Out Whether a MOA Is Hot
Four methods came up, and they are not equally reliable.
| Method | How it works | Limitation |
|---|---|---|
| Sectional chart margin | Published times and altitudes are printed along the chart edge | Tells you the scheduled period, not whether anyone is actually flying |
| EFB data layer | Enable the aeronautical data layer and tap the MOA to read times and altitudes | Same limitation — schedule, not reality. Also depends on which layers you have switched on |
| NOTAM layer | In some EFBs the MOA shades red when activated by NOTAM | Only works for MOAs activated by NOTAM. Many simply have published periods and generate no NOTAM at all — they will never shade red, and that silence means nothing |
| Call ATC and ask | Contact the controlling facility and ask directly | Requires radio contact, which can be difficult at low altitude in remote terrain |
The NOTAM caveat is important enough to restate: the former controller pointed out that MOAs he worked had published activity periods with no NOTAM issued. A pilot relying on red shading would conclude they were cold. They were not.
Just call and ask — you don’t need flight following
This was the single most practical takeaway. You can simply ask a controller whether a MOA is hot, and you do not need to request flight following or any other service first. It is a routine question, comparable to asking whether a parachute jump zone is active.
The answer you get is often more useful than anything a chart can tell you — that it is active but everyone is working above a certain altitude today, or that it is scheduled but the participants are running late and will not start until the afternoon.
Even if you choose not to check in, monitor the frequency. You will hear controllers clearing military aircraft into and out of the area. One caveat: if the military side is operating on UHF you will only hear the controller’s half of the conversation.
Published FAA guidance adds a further step this session did not mention: pilots are advised to contact the controlling agency or a Flight Service Station for real-time status when operating near a MOA. Check current AIM guidance for the recommended distance and procedure.
What Actually Happens When You Fly Through
Three findings from the session reframe the risk.
1. ATC is not talking to them continuously. Asked directly whether controllers maintain two-way contact with military aircraft inside a MOA, the former controller’s answer was an unambiguous no — the flight is handed to a tactical frequency to coordinate among themselves, and ATC retains the ability to reach them rather than an ongoing conversation. Inside larger range complexes, ATC may not be the controlling authority at all: the flight checks in, then self-controls tactically.
2. “See and avoid” runs into task saturation. Fighter crews do scan, and mid-air avoidance is taken seriously — many carry radar and crews are held accountable internally for getting too close. But they are training, exactly as you are when you practice maneuvers, and they cannot scan everything continuously while maneuvering hard.
3. The speed mismatch is the core hazard. Fighters are reluctant to operate much below roughly 150 knots; a light single cruises around 100. Closure rates leave very little time, and a slow-moving target is genuinely difficult to work with.
The coordination payoff
This is the number that should change behaviour. According to the former F-15E crew member, when an aircraft appears in an exercise area with unknown intentions, controllers protect it with a substantial buffer — on the order of 5 miles laterally and 5,000 feet vertically. Fighters then have to sanitize their maneuvering around a moving bubble.
If you coordinate — so your route and altitude are known and can be broadcast — that buffer shrinks to roughly 1 mile and 1,000 feet, and the exercise can be deconflicted around you rather than suspended.
The alternative to a moving bubble is a hard artificial floor. In a MOA used for maneuvering between roughly 10,000 and 18,000 feet, a single transiting aircraft at 12,500 can force a shelf at 13,500 — cutting the usable training airspace roughly in half.
He put a figure on the waste, described as a personal recollection rather than an official number: on the order of tens of thousands of dollars per aircraft per hour. His framing was notably even-handed — it is your right, and it is America, but that is the impact.
I don’t know, sir. You’re in a hot MOA, and I’m not talking to them.
— ATC to a turboprop pilot who had just had a very close encounter (as recounted in the session)
That account is second-hand and the outcome is unverified — it is included as an illustration of the dynamic, not as a documented incident. The more useful part is the explanation offered for how it can happen without anyone behaving badly: if a flight has deconflicted using a hard floor rather than a bubble, a hard-maneuvering aircraft can descend to the bottom of that floor and end up far closer to a transiting aircraft than anyone intended.
Military Training Routes: The Line Is Not Where the Jet Is
MTRs are the other half of the picture, and Miller’s view is that most civilian pilots neither study them nor listen on the frequencies the military is actually using.
IR and VR, and what the numbers mean
There are two types. IR is an IFR Military Training Route — operations are conducted in accordance with IFR regardless of the weather. VR is a VFR Military Training Route. Both may be flown at speeds in excess of 250 knots.
The numbering convention is genuinely useful once you know it, and it is published in AIM 3-5-2:
- Four digits (for example IR1206 or VR1207) — the route has no segment above 1,500 feet AGL.
- Three digits (for example IR206 or VR207) — the route includes one or more segments above 1,500 feet AGL.
Miller flags the practical trap: a three-digit route tells you it goes above 1,500 AGL, but not how far above. That is the number you cannot read off the chart.
Note: in the session an initial figure of 1,400 feet is stated and then corrected on air to 1,500. The 1,500-foot threshold is the published one.
How wide is a route?
Wider than the thin line suggests — and this is the point that should change how you cross one. The former crew member’s rule of thumb was that a VFR route commonly has something like five miles of usable corridor either side of the centerline, occasionally more, while IFR routes are flown considerably tighter to the charted line.
Crucially, the military treats that entire corridor as maneuvering space — displacing off centerline to practice a ridge crossing or set up a simulated attack. The charted line is a reference, not a track.
These widths are recollections rather than charted values. Actual MTR dimensions are route-specific and published in the DoD Flight Information Publication (AP/1B), not on VFR sectionals.
Who knows whether a route is active?
The most actionable line in the whole segment came from the controller’s side: ATC will generally know whether an IR route is active, because controllers must separate traffic from it whether or not they are talking to the military aircraft. For VR routes, ATC may not know whether anyone is on it.
Military crews scheduled routes and checked in with Flight Service before the entry point, passing route, entry and exit points, altitude and speed — routes have published entry points rather than being joined anywhere. The crew member was careful to say he could not speak to current practice.
Also worth knowing: sectionals carry boxed special military activity notes that provide a contact facility and frequency for specific areas. Those notes did not surface in the EFB data layer during the session — which is part of Miller’s broader argument that layer-driven charts hide things, because you have to know what to switch on. His refrain: do not abandon the paper sectional.
One hazard that sits outside the route entirely: before dropping into a low-level, crews may fly a high-G warm-up maneuver at altitude — analogous to clearing turns. That happens near, but not on, the charted route. Proximity to an MTR is worth respecting even when you are not crossing it.
If You Are Intercepted
The session covered intercepts in useful detail, largely in a post-9/11 and TFR context rather than a MOA one.
- Tune 121.5 immediately. That is VHF guard, and it is where an interceptor will try to reach you. (Controllers reaching military aircraft may be using UHF guard — a different frequency for a different audience.)
- Expect a two-ship. One aircraft appears off your left wing; assume a second is behind you. When the lead moves, the roles swap.
- Comply with radio instructions. If you have no radio contact, comply with visual signals.
- Follow the turn. If the interceptor pulls ahead, rocks its wings and turns, that is the direction they want you to go.
- Do not dive. An aircraft descending toward a protected site reads as exactly the wrong intent. In one account relayed in the session, that instinct brought a pilot closer to a very bad outcome than anything else.
A myth gets corrected along the way: the popular claim that interceptors always come close enough to see what you are wearing is not how it works. How close they need to get depends on the level of identification the controlling agency has asked for.
For authoritative intercept procedures and signals, refer to the AIM (section 5-6) rather than any summary — including this one.
The clearest illustration in the session involved a light aircraft tracking toward a sensitive facility shortly after 9/11. Fighters flew several passes in front of it to get the pilot’s attention and were never seen. The takeaway Miller draws is the right one: had radio contact been established, none of it escalates — someone simply asks the pilot to turn.
The Bottom Line
Nothing here says you cannot fly through a MOA. You can. The argument is that the cost of one radio call is close to zero, and the benefit is substantial in both directions — a far smaller deconfliction buffer for the exercise, and a far better picture of what is actually happening for you.
For MTRs, the practical shift is to stop reading the line as a track. Assume the corridor is miles wide, remember ATC’s knowledge is better for IR routes than VR, and check the boxed chart notes that give you a facility and a frequency.
And read the NOTAMs along the whole route of flight, not just at the ends.
Frequently Asked Questions
Can civilian pilots fly through an active MOA? Yes. A Military Operations Area is not restricted airspace, and VFR aircraft may legally enter without permission whether or not it is active. However, doing so uncoordinated typically forces controllers to build a large protective buffer around you, which can suspend military training entirely.
How do you find out if a MOA is hot? Published times and altitudes appear on the sectional margin and in EFB data layers, but those show the schedule rather than actual activity. The most reliable method is to call the controlling facility and ask directly — you do not need to request flight following first. NOTAM-based red shading in EFBs only works for MOAs that are activated by NOTAM; many are not.
Why do charted MOAs show altitudes above 18,000 feet? MOAs themselves are established below 18,000 feet. When a chart shows a higher top, a separate block of ATC Assigned Airspace (ATCAA) has been scheduled on top of the MOA, allowing the military to reserve a taller volume for an exercise. This matters for IFR pilots, who may be kept high longer than expected.
Is ATC always talking to military aircraft in a MOA? No. Military flights are typically handed to a tactical frequency to coordinate among themselves. Controllers retain the ability to reach them but are not in continuous two-way contact, and inside large range complexes ATC may not be the controlling authority at all.
What do IR and VR mean on Military Training Routes? IR is an IFR Military Training Route, flown in accordance with IFR regardless of weather. VR is a VFR Military Training Route. Both may involve speeds above 250 knots. Per AIM 3-5-2, four-digit route numbers indicate no segment above 1,500 feet AGL, while three-digit numbers indicate the route includes segments above 1,500 feet AGL.
How wide is a Military Training Route? Much wider than the charted line suggests — military crews maneuver across the full corridor, which may extend several miles either side of the centerline. Actual dimensions are route-specific and published in DoD Flight Information Publication AP/1B rather than on VFR sectionals, so treat the chart line as a reference rather than a track.
What should you do if you are intercepted? Tune 121.5 immediately, expect a two-ship formation with one aircraft off your left wing and another behind, comply with radio instructions or visual signals, and follow the direction of the interceptor’s turn. Do not descend toward a protected area. Refer to AIM section 5-6 for authoritative intercept procedures and signals.
This article summarizes a discussion from The Finer Points and is general educational information, not instruction. Participants spoke from personal experience and some figures are recollections rather than published values; several are noted as such above. For authoritative guidance refer to the AIM, current charts and NOTAMs, and the relevant FAA publications.
