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Paulm1949
31st Aug 2021, 10:19
If I accept my own terrain clearance from ATC and cleared to a 10 mile final for example (obviously VMC) do I still have to obey the radar minimum altitudes? I’m guessing not as I’m not under radar control. However what’s the reason for them? Would the best idea in the above situation be to remain at the 25nm MSA until established on the loc?

Check Airman
31st Aug 2021, 15:55
Just to be clear when you say “accept your own terrain clearance”, you’re talking about a visual approach, right?

If so, in the FAA land, you can do whatever you want without reference to the radar minimum charts. They aren’t even published for most US airports- at least not in our jepp sets.

Paulm1949
31st Aug 2021, 16:31
No I’m not talking about a visual approach. Rather a self position to a 10 or 12 mile final for the ILS for example.

Some places allow it providing you’re VMC and in sight of the surface.

However I’d be reluctant to zoom down to the platform altitude even if I was visual with the ground whilst still being say 15 miles out on some wide left base for example.

Just wondering what others do in this situation? Go off the radar minimum chart , the MSA, the platform altitude?

Thanks

FlightDetent
31st Aug 2021, 17:27
The question is incomplete:

Airspace Class:
ATS service provided
Last clearance
Precise wording of the instruction
Applicable VMC minima
Flight Rules

and not least, what is the pilot tryin to achieve.

jmmoric
2nd Sep 2021, 13:05
If you're IFR and not cleared a visual approach, are you even allowed to descend below the MSA until either established on the approach or flying a visual approach? ATC cannot give you permission to break the rules. Same with speed restricted by airspace classification (250 below FL100), you can ask all you want, but you're still not allowed to go faster.

But for enroute we're not allowed to give clearance below "minimum flight altitudes". And the responsibility lies with ATC during vectoring or rerouting where we take the aircraft off track.... generally.

island_airphoto
2nd Sep 2021, 19:46
Paulm1949

Do you mean a practice ILS in VMC? I cannot imagine getting such a clearance in IMC.

Denti
3rd Sep 2021, 13:08
Same with speed restricted by airspace classification (250 below FL100), you can ask all you want, but you're still not allowed to go faster.

I guess that depends where. Over here there is no speed limit in Class C airspace, even below FL100. Which is the explanation why there is quite a bit of C around bigger airports.