ok, it seems it's only for GPS and RNAV approaches if I got it right?
What about lost comms?? I mean, I'd have to be at certain fix at the certian time or hold until the time is right when I get there. Would that be considered a timed approach as well? Would it also require an operational tower? The section about timed approaches from a holding fix requires the communication with the tower though. This is a bit confusing. In which case would anyone use a timed approach anyway? I guess only when directed by controllers for traffic separation or something?
Hey skidz, I'm going to address your questions in reverse order and see if I can make sense of it for you.
First, you asked in what cases would timed approaches be used. The most obvious example that I can imagine would be in a non-radar environment. Imagine a controller has 4 aircraft stacked up at the holding fix, which is also a FAF to an approach. The guy on the bottom of the stack is holding at the FAF altitude, and each of the other 3 above him is another 1,000 feet higher. Well, if he needs a certain amount of time in between them for landing, say 5 minutes, he could clear the bottom guy to depart the fix inbound at 1200Z, then the next guy to depart the fix at 1205, and so on.
As for the lost comms question, it's not really addressed there under TIMED approaches, but what you do is addressed elsewhere, under lost comms. FAR 91.185 or AIM 6-4-1 (quoting from a 2006 book, but this hasn't changed).
section C (1) talks about your routing, and basically says that you follow the last Assigned, Vectored, Expected or Filed routing, in that order.
section C (2) talks about your altitude and says that you use the highest of your last Assigned, Expected, or the Minimum as prescribed in 91.121
section C (3) is the part that is really germaine to the question. You use your AVE-F routing and MEA altitudes from above to get to your clearance limit. Once you are AT your clearance limit, if your clearance limit is an IAF for an approach that you can fly, you begin the approach and land. You attempt to make your ETA as close as you can, unless you got an EXPECT FURTHER CLEARANCE TIME before your radio failure. If you got an EFC time, then you hold until your EFC time expires, and THEN shoot the approach.
If instead your clearance limit is NOT an IAF for an approach that you can fly, you proceed from that point to an IAF for an approach that you can fly and fly the approach. Attempt to make your ETA to the best of your ability, if you haven't received an EFC. If you have received an EFC then you hold at your clearance limit until your EFC expires and then go to an IAF for an approach that you can fly.
Keep in mind that the instructions are slightly vague and section a of AIM 6-4-1 always applies:
a. It is virtually impossible to provde regulations and procedures applicable to all posible situations associated with two-way radio communications failure. During two-way radio communications failure, when confurnted by a situation not covered in the regulation, pilots are expected to exercise good judgemnt in wtever action they elect to take. ...
NONE of the above mentions anything about an operable control tower. And you wouldn't be able to tell if the tower were operating if you lost your radio anyways, because the tower could go down while you were flying there and you'd never know. The lost comm stuff gives you general guidelines and leaves it up to pilot judgement for exactly the reason that section a. talks about. It would be impossible to provide strict regulations that cover every scenario, so instead they give you some basic guidelines but leave the rest up to pilot judgement. So you just try to use good judgement and be predictable.
