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mb339
14th Feb 2006, 22:45
Before departure in a small airport in the northern of italy, we were cleared to follow a SID. The last waypoint was VIC, with a minimum crossing level of 120, as stated in the departure chart.
Just after departure, identified and under radar control, ATC cleared us direct to VIC without following any SID.
My question is: When under radar control, if ATC gives me a direct to, is terrain separation pilot's responsability or ATC's responsability (Minimum vectoring altitude applies)?
In other words: is a direct to considered as a vector?
Thanks

Pierre Argh
14th Feb 2006, 22:56
Notwithstanding International variances in procedures (and believe me they exist!)...

Under Radar Control the Controller is responsible for Terrain Clearance. An SID will assume minimum climb rates and is be designed to provide TC, the CAS structure will provide TC... OK that's a given.

In the instance you describe, when the Controller took you off of the SID and cleared you DCT VIC, you can be entitled to assume they have taken TC into account.

Mind you, that doesn't mean you shouldn't cross-check after all you're the one in the air!!!

mb339
14th Feb 2006, 23:06
Thank you for your very quick answer!

I knew that only case ATC is responsible for terrain clearance was during radar vector, but not in any case when under radar control.

Could you confirm this?

M609
14th Feb 2006, 23:16
Radar control? No, still you in many countries.(You are still on own navigation) Vectors, the controller.
That said, I never issue DCT below MSA due to the fact that rules are different around the world. If I need to give a instruction early, I slip in a "through xxxxft........". (The fact that mb399 asks kinda sements that issue!)

Pierre indicates that the CAS structure provide TC. That is a very dangerous assumption. (And veeeery wrong some places!)

Spitoon
15th Feb 2006, 05:55
This is a very grey area that has come up before.

I seem to recall that ICAO was going to change the wording in their book and I'm not sure exactly what it says at the moment but the simple rule used to be - when pilot is under own navigation, the pilot is responsible for terrain clearance, in other situations it's ATC. As far as I recall the book said nothing about what service the aircraft was receiving from ATC.

So the grey area was if ATC cleared an aircraft to route own navigation from A to B but is still watching on radar and could just as easily have put the aircraft on a heading to the same place - who is responsible?

This has been the cause of some deep philosophical debates amongst myself and colleagues over the years - with roughly equal numbers on each side of the fence.

I hope that the ICAO rules are now clearer - I guess it will be in PANS-ATM. I'll try to have a look next time I get a chance and give an update if necessary.

Empty Cruise
15th Feb 2006, 11:49
Unless specifically stated in said countrys AIP, own navigation = own terrain separation. My advice ( :rolleyes: )would be to follow the SID up to the MSA, then fly direct, unless you have visual contact with the terrain...

Empty

Pierre Argh
15th Feb 2006, 16:11
Notwithstanding International variances in procedures (and believe me they exist!)...
See what I mean?

mb339
15th Feb 2006, 17:32
Thanks everybody who helped me

I've just found the answer to my question.

I found it on DOC4444 Amendment N°4 para 8.6.5.2.

It writes: "when vectoring an IFR flight and when giving an IFR flight a direct routing which takes the aircraft off an ATS route, the radar controller shall issue clearance such that the prescribed osbtacle clearance will exist at all times until the aircraft reaches the point where the pilot will resume own navigation."

It appears clear that things has recently changed!

Max Angle
15th Feb 2006, 21:57
When under radar control, if ATC gives me a direct to, is terrain separation pilot's responsability or ATC's responsabilityIt doesn't matter what it says in any document, as the pilot in command YOU are responsible for terrain clearance 100% of the time.

galaxy flyer
15th Feb 2006, 22:27
I quite agree with Max Angle, no matter what the books say--it is your A** that will come in contact with terrain. The controller maybe the subject of the BOI, but you will only be fondly remembered.

Always, always, be familiar with the local terrain BEFORE accepting any directs at low altitude. The MORA altitude at a minimum, if published. Fly in South America once in awhile and you will be amazed at the clearances given, many controllers there still believe it is their job to separate you from other planes, the operation of your plane is your business, including terrain.

GF

mb339
15th Feb 2006, 22:49
I know I know!

I did that question to a lot of people, and all had their own idea about that subject! That made me think!!

I think I will continue to be responsible for terrain separation... ;)

Bye