Lost Comms Instrument Approach Question

pavelump

Well-Known Member
I'm having a little bit of a hard time figuring this one out...

Low-Alt. Enroute Section

Madison, WI ILS 36

OK, say that I'm flying up to Madison via victor airways from the south. Just for fun, lets say that I've departed O'hare and am proceeding to MSN via V24 and V9.

My flight plan is from ORD to MSN via

OBK V24 JVL V9 MSN

Along the line, I get switched over to Rockford approach, but oops, something seems to have happend to my radio(s). Luckily, I already received ATIS at MSN and it advised that ILS for runway 36 is in use. I'm in IMC, so landing at another airport is out of the question.

So far, no big deal. Remain calm, fly the airplane, squawk 7600 and proceed as filed. So I get out my ILS RWY 36 approach chart and notice that MSN is not an IAF, but on closer inspection, I notice that there is a feeder route off of MSN on the 180 radial. (I think that I may have just answered my own question, but...)

Should I:

a) Proceed to the VOR and make a 161 degree left turn (or a 199 degree right turn?) to get on to the feeder route to the LOM (which is the only IAF) and commence the full approach, or

b) Proceed direct to the LOM when I get within range and make a course reversal to do the full approach, or

c) Tune in the ILS localizer and "vector" myself onto it.

I'm leaning towards choice A, but I'm not 100% sure.

Dave
 

Tired

New Member
Purpose of a feeder route is to get you from the enroute structure to the IAF. So, just fly to MSN, then is looks like fly the 180 for 4.9 miles, then fly the procedure turn as published.
 

EatSleepFly

Well-Known Member
[ QUOTE ]
a) Proceed to the VOR and make a 135 degree left turn (or a 225 degree right turn?) to get on to the feeder route to the LOM (which is the only IAF) and commence the full approach, or


[/ QUOTE ]

That would be my choice as well. Direct MSN, then the 180 radial feeder route at 2700, then the full approach.
 

pavelump

Well-Known Member
That's what I figured, but what if I had been passed on to the MSN approach control who began to vector me towards the localizer (before clearing me for the approach).

Go direct to the LOM(IAF) and turn around for the full approach?

Dave
 

EatSleepFly

Well-Known Member
From 91.185(c)(3):

"...<snip>...proceed to a fix from which an approach begins and commence descent or descent and approach...<snip>..."

So yeah, I'd go direct to the LOM/IAF and do the full approach.
 

Ralgha

Well-Known Member
If the controller had started giving you vectors before you lost your communications, then you should proceed direct to the fix or course that the controller said he/she was vectoring you to. That's why they say "vectors to ...".
 

EDUC8-or

Well-Known Member
I'm going to agree with ESF and go to the IAF. If you're really expecting the weather to be crappy it's always a good idea to file to the IAF for an approach and then on to your final destination. How many of us honestly do that? But if you lose comms you can hold and depart the hold to arrive at your ETA.
 

Ralgha

Well-Known Member
Yes, even if it's not an IAF. However, if you're not cleared for the approach, then you'd have to fly the ILS final approach course (in this case) to the airport (your clearance limit), then turn around and fly back to the IAF and execute the approach. If you are cleared for the approach before you lose communications, can just execute the approach.

Thanks for the compliment on the website. I have grand plans for it, I already have an online scheduler geared toward independent flight instructors (not affiliated with an FBO, though it would work for them too), but it's got a couple things I'd like to polish before letting anyone else use it (I've been using it for myself). I'm planning to make it a sort of a learning portal for instructors and their students, as well as a central location for help in flight training and a directory of flight instructors.

I threw the forum up so there would be something there, I wanted one anyway, and it was easy to set up. Now I just need some traffic!


On a side note, the airplane logo on the forums is an edited (obviously) photograph of one of the airplanes in my flying club taken by my passenger from the plane I was flying at the time. Our gear horn was going off to stay alongside it with them at cruise power...hehe.
 

SteveC

Really?
Staff member
If I was getting "vectors to the final approach course" I'd intercept, turn inbound, and fly the approach.

If the vectors that you were given won't intercept (you have been paying attention to where you are in relationship to the airport and approach course, haven't you? Can you say "situational awareness"?), I'd say it's a judgement call on whether you give yourself a vector to intercept, or just turn direct to the fix for the procedure turn.
 

Tired

New Member
Depends on your equipment, and the terrian. If your over Kansas and have a moving map GPS then you can easily vector yourself to the final approach course. However, without DME or GPS...even with good SA how are you going know exactly where to go. Safest course of action, and what I would do, is to climb to the MSA, fly to the IAF, and execute the full procedure.
 

Ralgha

Well-Known Member
That would probably work out ok, but if you haven't been cleared for the approach yet, then you haven't been sequenced yet. There may be a conflict arising that they would have to change your vector for, which is why you should technically follow the final approach course to your clearance limit, depart that at your ETA, and then go to an IAF and fly the approach. That way the controller would ensure that the approach was protected for you.

The rule says you proceed "directly" to the fix, route, or airway to which you are receiving vectors. Technically this would mean (with a route or an airway) you intercept that route at a 90 degree angle (the shortest path to it), but just remaining on your vector (if it will get you there) would probably be fine.
 

pavelump

Well-Known Member
[ QUOTE ]
If the controller had started giving you vectors before you lost your communications, then you should proceed direct to the fix or course that the controller said he/she was vectoring you to. That's why they say "vectors to ...".

[/ QUOTE ]

Maybe I should have been more specific. Lets just say that I am 15 NM SE and the MSN controller says, "Turn left heading 270, expect the ILS 36" and then zap! No more radio. Seems to me that the second part in 91.185 pertaining to route...

"If being radar vecotred, by the direct route from the point of radio failure to the fix, route, or airway specified in the vector clearance"

...would mean to proceed direct to the IAF staying above the MSA for that approach. Then I would presumably hold over the LOM until I got close to my ETA listed on my flight plan.

Dave
 

Ralgha

Well-Known Member
In that case, you know of an expected route (the ILS), so you would fly that route to your clearance limit. You still have not been cleared for the approach, so you should fly to your clearance limit (probably the airport) via the ILS final approach course, then proceed to an IAF and begin the approach as close to your ETA as possible.

The controller has said to expect the ILS, so you're not even getting vectors to it. There's even less chance that it's protected for you to fly the approach than if you are getting vectors to it.
 

pilot602

If specified, this will replace the title that
Wait. So you want someone to fly from the IAF, to the airport (I'm assuming at the hold altitude or MSA) do a course reversal, fly back to the IAF, do another course reversal and then shoot the approach?

Why aren't you just holding at the IAF until the ETA and then shooting the approach like the regs say?

[ QUOTE ]
91.185 ... 3(ii) If the clearance limit is not a fix from which an approach begins, leave the clearance limit at the expect-further-clearance time if one has been received, or if none has been received, upon arrival over the clearance limit, and proceed to a fix from which an approach begins and commence descent or descent and approach as close as possible to the estimated time of arrival as calculated from the filed or amended (with ATC) estimated time en route.

[/ QUOTE ]

So in this situation you would go to the clearance limit (fly 270 till you intercept the LOC), then follow the LOC into the IAF, hold, and then begin the approach as close to the ETA as possible. But because you were on vectors and assuming you had updated ATC to any delays (if there were any) chances are you're already awfully close to your ETA so I'd go 270 to the LOC and shoot the approach.
 

Ralgha

Well-Known Member
When getting vectors you probably don't go to the IAF, and your clearance limit (in my examples) is the airport. When the controller says "expect the ILS" that's a routing expectation, not a change to your clearance limit. Unless your clearance has been amended, your clearance limit is what you got when you picked up your IFR clearance, "cleared to ...". The "expect ILS" is the route you take to get to your clearance limit. The regs say you depart your clearance limit so you can begin the approach from an IAF at your ETA. You can't depart your clearance limit if you never went to it.
 

pilot602

If specified, this will replace the title that
[ QUOTE ]
When getting vectors you probably don't go to the IAF, and your clearance limit (in my examples) is the airport. When the controller says "expect the ILS" that's a routing expectation, not a change to your clearance limit. Unless your clearance has been amended, your clearance limit is what you got when you picked up your IFR clearance, "cleared to ...". The "expect ILS" is the route you take to get to your clearance limit. The regs say you depart your clearance limit so you can begin the approach from an IAF at your ETA. You can't depart your clearance limit if you never went to it.

[/ QUOTE ]

Read this again:
[ QUOTE ]
If the clearance limit is not a fix from which an approach begins, leave the clearance limit at the expect-further-clearance time if one has been received, or if none has been received, upon arrival over the clearance limit, and proceed to a fix from which an approach begins and commence descent or descent and approach as close as possible to the estimated time of arrival as calculated from the filed or amended (with ATC) estimated time en route.

[/ QUOTE ]

The controller was vectoring you to the ILS with the expectation of commencing the approach upon reaching the LOC. He is not expecting you to over fly the airport, turn around, fly to the IAF, turn around and shoot the approach.

The regs say proceed from the clearance limit to a fix from which an approach begins. The regs also say "fly the last instruction (vector)."

[ QUOTE ]
(ii) If being radar vectored, by the direct route from the point of radio failure to the fix, route, or airway specified in the vector clearance;

[/ QUOTE ]

So in this case I'd fly 270 to the LOC (which is the route) follow it to the LOM and commence the approach. You were told to expect the approach so that's what your doing - the last instruction given. I think flying to the airport and then back (against the flow of traffic no less, in IMC) would be creating more problems than it solves.

Just my stupid opinion.
 

Ralgha

Well-Known Member
You're not being vectored to the ILS. The controller said expect not vectors to .... Granted, I don't know if you would ever hear something like this, but I'm not the one who created the scenario. Normally they would say "vectors to". "Expect" is usually something you hear soon after contacting approach and while you're still own nav.

The controller is not necessarily going to vector you straight to the localizer and then clear you for the approach. He/she may vector you around for spacing, possibly through the localizer and intercept from the other side.

All you have in this situation is an expectation of further routing.

You read this again.
[ QUOTE ]
If the clearance limit is not a fix from which an approach begins, leave the clearance limit at the expect-further-clearance time if one has been received, or if none has been received, upon arrival over the clearance limit

[/ QUOTE ]

Your clearance limit is the airport (in my examples). You can't leave the clearance limit if you never got there.
 

SteveC

Really?
Staff member
My understanding is that the controllers are required to tell you the reason for the vectors. You might hear "expect the ILS 36" on initial call-up, but when they change your routing you'll hear "fly heading , vectors ILS 36" or "fly heading for traffic (or spacing)" or something similar.
 
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