I can't imagine trying doing 540 KIAS low level and having to spot / dodge GA traffic.
9 miles/min. And that's within the structure of the MTR. However an MTR is general airspace, with anyone having a right to in/around/near; so yeah, it can be a challenge.
Military Training Routes are usually never in "military-only areas" such as Restricted Areas, etc. As military pilots, we train like we fight; and if that means a 450 knot low-level ingress to a target, then that's what we do. There's a reason that MTRs in the USA are depicted on Sectional Aeronautical Charts and the US AP-1/B chart; that's so civilian pilots can plan around them, and either avoid them, or be able to be VERY heads-up if they must fly near them. When I say "must fly near them", I'm referring to some MTRs which come within (due to terrain) some small private, uncontrolled airstrips, such as those near ranches, etc. In these instances, civilians need to go in/out of these fields, and knowing the status of a particular MTR near you is important.
However, it's perfectly legal for anyone to fly through/in MOAs and along MTRs, but that's not the question. As you know, in VMC, it's everyone's responsibility to see and avoid.
But here's a good example of the problem: In the A-10, I had no radar for my low-levels, my only separation ability comes from the Mk.1 eyeball. Keep in mind, though, that I have a multitude of cockpit tasks going on while tooling along at 300 AGL/360 KIAS. First, eyeing terrain to make sure I'm doing my job of pilotage correctly (ie- matching terrain features with what's on my map to make sure I'm going the right way), avoiding hitting the ground/power lines/near rocks/far rocks, keeping track of my timing per leg [if I'm going for a specific TOT, or Time Over Target], keeping track of my other aircraft in my formation, ensuring my weapons panel is set correctly [such as setup change from air-air to air-ground], going over and over in my mind what the attack plan is [formation, role, weapon, timing, attack axis], and being ready to flex to a different plan if the first one gets screwed up [such as unplanned threats pop-up], and maintaining overall SA over the operation; all while moving at 300 AGL/360 KIAS; and all this in addition to trying to see and avoid. Truth be told, we really expect (hope) that civilian pilots won't be in our path because they HAVE done the necessary pre-planning for their flights. Even in radar equipped fighters, the pilot isn't sitting with his head in his scope while tooling along at low level, so he may not notice civilian hits on his scope. In addition, some radars are even programmed to negate hits below certain airspeeds, in order to reduce the scope clutter. Also, at the speeds mentioned, I'm moving @6 miles/minute (A-10), or 8-9 miles/minute (other fighters); a Cessna 152 would probably be visibly detectable for only a couple of seconds before I flashed past it. Point? Everyone practice the best see-and-avoid they can; but also civilian pilots should be aware of where Military Training Routes are and, preferably, avoid them. Military pilots should know what their route structure is, and remain within it.
One of the problems too is all FSS will have is a scheduled entry and exit time for the route in question. The aircraft using the route make a one time call entering and a one time call exiting on 255.4, which is the general UHF FSS freq. FSS may or may not catch the call, so even if a route is scheduled to be active, there's no real way to confirm if it truly is, and even so, there's no real way to know where the aircraft are on the route, unless you have UHF capability. Many routes have restrictions placed into them for "remain above XXX AGL for noise sensitive area between point B and C".....things like that. But they are low-level training routes, so common-sense speaking, it's unlikely they'll be that high, AGL-wise. Still, it never hurts to avoid them laterally if at all possible; or if crossing them or near them, just keeping a little more of an eye out.
For the calls entering/exiting, most guys don't even know which FSS services the area in question, so the general call on 255.4 goes something like this: "Any radio, any radio, Grip 21 flight of 2 entering VR-244 point Bravo for the next 20 minutes". So, unless someone happens to:
1. Have UHF
2. Have been listening and caught the call
3. Know where the VR or IR route in question is located, &
4. Know where the individual entry/exit points are located....
...then the call won't be of much help.
On the altitudes, a good thing to know is the numbering system for MTRs, both VR and IR. If the MTR has a 3-digit number, ie- VR-244, IR-168, that means that there are segments along that route that have portions above 1500 AGL. If the MTR is 4-digit, ie- VR 1288, IR-1403; that means that there are no segments on that route that are above 1500 AGL.
Where I am, PHX and TUS airspace (among others) is getting more and more crowded, that's part of the reason for the closure of Williams AFB. And I fully understand that airspace is getting smaller and smaller; hell, most of the state of Arizona is Special Use Airspace of some sort, just look at the PHX sectional. Hopefully, even as this happens, GA and military can still co-exist without conflict.
