Look at this ILS chart please:http://aeronav.faa.gov/d-tpp/1011/00330IL10L.PDFIs it possible to fly this approach own navigation or full procedure? I don't see any IAF's, so I figured one has to be vectored for it.But, could you fly the BTG R234 and then join the localizer? Is that valid?

Looks to me like coming onto a BTG radial and intercepting the localiser should work, but that you need the ground to assist in order to make it entirely legal/safe purely because of the 'Radar Required' notification on the chart. So that suggests some kind of spanner in the works which makes an ILS intercept not entirely feasible or safe from doing it that way.Not being familiar with that place I don't know if the aerodrome booklet for Portland might specify some local reasons for the Radar Requirement, such as terrain possibly adversely affecting instruments or the ILS signal, or there being excessive downdraughts on the way in from the west or whatever, i.e. maybe that high terrain off to the WNW causes something weird, so my guess is that it could be something like that, although that is just a guess.I do know that when a FAF is something like an intersection rather than a specific Navaid and thus less accurate for some aircraft without fancier avionics, or there is no clearly defined route into the place for typical flights coming off an airway looking for an IAF, they'll sometimes classify things as Radar Required and steer people there instead with radar vectors. It could also be that where the IAF would be, there's only clunky old beacons available which can't legally be used for procedure turns or some such. Dunno really, but I bet there's some reason like that for it, and if that's the case, then radar might steer you for what is effectively a radial intercept of the ILS via BTG, but make it legal as far as the charts are concerned, by actually doing it via radar.I guess someone who flies around there could probably tell you for sure, and if this is not a simulator-only related query and you really are going to fly into there, then you could always call the airport and ask them about it, or get the aforementioned aerodrome booklet for the place and check things out in more detail, although in FS, I'd probably just come in on the radial like you suggested!Al

Hi Ryan,From the FAA Pilot / Controller GlossaryRADAR REQUIRED- A term displayed on charts and approach plates and included in FDC NOTAMs to alert pilots that segments of either an instrument approach procedure or a route are not navigable because of either the absence or unusability of a NAVAID. The pilot can expect to be provided radar navigational guidance while transiting segments labeled with this term.

But, could you fly the BTG R234 and then join the localizer? Is that valid?

So for a "real life" approach: No... you will have to have Radar Services to be vectored to the Final Approach Course.It is a very interesting question... why label the point as to how to identify, then apparently not be able to ID it?Part of the answer from the Instrument Procedures Handbook:"When vectoring aircraft to the final approach course, controllers are required to ensure the intercept is at least 2 NM outside the approach gate." Max Intercept is 20°. "In the absence of radar vectors, an instrument approach begins at an IAF."If BUXOM was an IAF, "the aircraft is expected to commence the approach using the published feeder route to the IAF or from the IAF as appropriate. The aircraft would not be expected to overfly and return to the IAF or feeder route."My thinking is ATC can safely vector you onto the Final Approach Course (safely away and above the terrain to the West) outside of BUXOM, which if you did identify you can step down safely to 2300'MSL to TRAYL (being established on the Localizer Course).Intercepting the localizer course from BTG R-234, again if BUXOM was an IAF, Would obviously require a "course reversal" thus requires a Procedure Turn ("to establish the aircraft on the intermediate or final approach course") and you would see it depicted on the Approach Plate.All that make sense?

I do know that when a FAF is something like an intersection rather than a specific Navaid and thus less accurate for some aircraft without fancier avionics, or there is no clearly defined route into the place for typical flights coming off an airway looking for an IAF, they'll sometimes classify things as Radar Required and steer people there instead with radar vectors.

In this case, having an intersection as a FAF shouldn't pose a problem. There are cross radials from the BGT VOR for that specific reason. If an airplane only has an OBS, then the pilot will have to use the cross radials to know where they are on the approach....and where the FAF is as well. If the pilot has a fancy GPS, then well they are just peachy then aren't they.

Looks to me like coming onto a BTG radial and intercepting the localiser should work, but that you need the ground to assist in order to make it entirely legal/safe purely because of the 'Radar Required' notification on the chart.

Apparently I'm just a blind controller... those are the magic words I was looking for and didn't see. Radar required... Question answered.