RAS and Terain Clearance

[radar707]

According to MATS 1 under RAS, terrain clearance remains the responsibility of the controller.

According to the ANO under both RIS and RAS terrain clearance remains the responsibility of the PILOT.

Discuss

Obviously the Pt 1 is the ATC bible, but the ANO is the law.

[short&shapeless]

I will check the books when next in on Moday but my memory of the JSP318a (the mil atc bible) is quite specific in that a controller is only resposible for terrain clearance when providing a Radar Control service: I was sure that it was the same for civil controllers also (as highlighted and confirmed in the F15 CM thread at the top)

But as I say I will check on Monday and post again, if you get no replies before then.

[vintage ATCO]

MATS Pt 1 actually says an ATSU providing RAS shall set a level or levels at or above which the aircraft . . . . and be provided with requisite terrain clearance. No mention of the word responsibility. Although elsewhere, it does say if taking aircraft out of the final approach area the radar controller resumes responsibility for terrain clearance whilst outside the final approach area. Semantics, I know.

But where is it mentioned in the ANO? I can't find any mention of RIS/RAS et al in a quick search in a pdf version.

---------------------
Steve
www.stevelevien.com

[Duke of Burgundy]

My interpretation has always been that the Minimum Height Rule (Rule 29) places the responsibility for terrain clearance squarely on the pilot.

In my opinion, ATC procedures for aircraft under a RAS or when being provided with vectors under a RIS are designed so as not to compromise terrain clearance rather than transfer responsibility to the controller.

[Evil J]

I would not provide a RAS or vector a RIS below a terrain safe level. I would vector a VFR RIS (if I had to) below terrain safe level but would emphasise that the pilot remained responsible for his/her own terrain clearance.

[rej]

Not wishing to be contentious, but here is one to throw a spanner in the works.

Whilst in discussion with a senior member of the ATC specialisation about application of service I was told that one should not even issue a vector to a FIS ac which is below Sector Safety Height. The main reason given was that, in issuing a radar vector, you are applying a radar service. I'm not convinced about that since JSP 318a states that FIS is a non-radar ATC service. However, all I would suggest is that we are all very careful. I admit that I have not seen anything written on this subject but I haven't issued a vector to such an ac since as who knows who will protect me if, god forbid, something goes horribly wrong.

What are the thoughts out there?

p.s. Remember the good old days when we could actually provide a service to pilots?

[AlanM]

If below a terrain safe level you could either;

(a) Refuse a radar service or

(b) Ensure they are good VMC, in contact with the surface and even suggest a "track xxx degrees maintaining VMC" - reminding them of the MSA for that area and any masts etc. Every time you change their heading and track say maintaining VMC.

Cover yr arse seems to be the only way to do this.

(only if RIS of course!)

[ATCbabe]

After reading this it got me thinking so I looked through old college notes.

I have found an AIC 20/1998 (yellow) which states:

(g) the pilot remains responsible for terrain clearance, although ATSUs providing a RAS will set a level or levels below which a RAS will be refused or terminated.

Dont know if this AIC is still current as it is quite old, but it certainly is clear in what it states. Need to check the AICs next time at work.

[bookworm]

My interpretation has always been that the Minimum Height Rule (Rule 29) places the responsibility for terrain clearance squarely on the pilot.

While that is undoubtedly true, Duke of B, it applies even under a radar control service in controlled airspace.

The ultimate responsibility for terrain avoidance always rests with the pilot, though that responsibility is sometimes delegated to ATC for expendiency. It's impractical for the pilot of an aircraft being vectored to be confident of terrain clearance to the precision required for approach control, for example. All the pilot has access to is airway MEAs and 25 mile sector altitudes, which may be well above the levels required for vectoring.

Outside controlled airspace, the waters are somewhat muddier, but there's still an awareness issue: unless the pilot has a moving map with terrain info, there may not be enough information for the pilot to check terrain clearance. He probably doesn't even know how long he'll be on the vector.

For those reasons I don't think controllers should offer vectors unless they are prepared to take responsibility for terrain clearance, and should refuse RAS below a level that would allow them to vector safely. On the other hand, I also think that pilots should either be confident of terrain clearance from their own information or explicitly check with ATC that terrain clearance is being provided.

Of course what I think and what the law is are totally separate issues. :)

[Evil J]

Rej,

It would be virtually impossible to approve any VFR zone transits on a busy day without putting them on some sort of heading where I work. Like you say I always put the caveat on of "report if unable to maintain VFR". Some would argue that even if VFR, when they enter CAS they get a RCS even if VFR;I've never managed to find a satisfactory answer to whether ths is true of not.

I welcome people's thoughts on this??

[singlestranger]

as an FC we follow the 318a, and set a FIS above the area safety altitude and are now obligated to get acknowledgement that " the pilot is responsible for terrain clearance". This has all been since the unfortunate court martial (F15s).

may be different for us FCs!

[KPax]

As a serving ATCO I am in no doubt re the rules concerning 'vectors below the RVC' you cannot give them. Even a suggested heading is taboo. Ask the pilot to report a level passing the base of the RVC, identify him then vector him. If he wants to know where he is try to give him a position to a location and then say 'own navigation report' ' then ask for a position within cover. I believe that it is an automatic ticket pull by the ATCEB if you give vectors below the RVC.

[Duke of Burgundy]

The UK AIP makes all of this very clear.

In the section on RAS it states that the pilot remains responsible for terrain clearance although ATSUs providing a RAS will set a level or levels below which a RAS will be discontinued or terminated.

In the section on RIS it states that the pilot remains responsible for terrain clearance. ATSUs providing a RIS will set a level or levels below which vectors will not be provided except when specified otherwise by the regulating authority.

To me it is apparent from this that as I said in my earlier post, the pilot is responsible for, but the controller`s procedures are designed so as not to compromise, terrain clearance.

It goes on to say that radar controllers have no responsibilty for the terrain clearance of and will not assign levels to aircraft in receipt of a RIS, or aircraft operating SVFR or VFR which accept radar vectors. (I know that there is an exception to the allocation of levels bit for single-engined aircraft over the City of London, but that is a minefield I don`t want to get into.)

In other words it is the responsibility of the pilot to remain in conditions which enable him to determine his flight path, keep clear of obstacles, comply with low-flying rules etc. If he needs to change heading or altitude to do this he must inform the controller.

In answer to Evil J`s question as to the radar service a VFR flight could be in receipt of within CAS, it is Radar Control Service. As the aircraft is inside CAS it can`t be anything else.

[rej]

Not wishing to disagree with Duke of Bs last but us "blue-suited"controllers do not give Radar Control in Class D airspace - we give an Air Traffic Service.

"What type of service is that ?" I hear you say - it's not defined, as are RIS/RAS/RC, in our 'Bible'. Not a great help but responsibilities for terrain separation and aircraft avoidance are stated. To add to that, not a great deal is taught about ATS in Class D on our ATC course.

[Whipping Boy's SATCO]

Rej, well you obviously work in the 'other' bit of Class D to that I worked in. At our unit we most certainly provided RCS or a (S)VFR clearance within the CTR; we merely did not state the TOS.

I do agree with you that the bible is somewhat lacking in it's guidance at Annex A. However, with the advent of more OOA deployments and procedural approach control training I suspect will will talk/learn far more about air traffic services inside CAS.

PS. Did you find the info in the Civil AIP about responsibility for terrain clearance on a (S)VFR flight?

[Chilli Monster]

rej

I'm intrigued. Why do you not provide Radar Control in your class 'D'? (Which I'm guessing I live just inside and work just down the road from ;)). JSP318A states RCS inside CAS same as the MATS part 1. Putting someone on radar control doesn't necessarily mean putting him on a heading (though you can) but it does mean for your VFR zone transitter you can specify a maximum transit level and route to fly / areas to avoid.

If this strange 'ATC' service is not defined in the JSP318A then you can bet your bottom dollar you'll get no support from the hierachy if something happens under it (a la 'spot'). What do the ATCEEB say? More to the point why are your class 'D' operations not in line with civil ones - it being the same class of airspace after all :confused:

[rej]

Maybe its just a matter of RT.

If you enter IFR we say "callsign entering XXXXXXX CAS, maintain FL/Alt/Height" and for VFR transits we say "callsign entering XXXXXXX CAS, maintain VMC". For either we do not say "entering CAS, Radar Control" but on leaving the Class D airspace we state the TOS the ac is now under.

I vaguely remember from my student days that you had to state the TOS as it formed the 'legal contract' between controller and pilot or am I just getting confused in my old age.

We separate IFR from IFR, and we issue traffic info to VFR traffic to allow it to separate itself from IFR. However, if we think that the VFR pilot may struggle to see/avoid IFR traffic then we reserve the right to build in separation. Under SVFR we obviously provide IFR separation.

As for the ATCEB, they do appear to think what we are doing is incorrect (in my time at this unit, I have seen 4 visits by Examiners). I am still waiting for clarification on other matters from the 'policy makers', which when I get an answer I will post here. I do not know why our Class D ops are not totally in line with Civilian rules (I am sure that in the main they are) but you are so right, we should all be singing off the same hymn sheet. I hear a little rumour that someone is starting to review them.

For W B S:
As for the Civil AIP, I would much rather use JSP318a as a little light bedtime reading than try and find my way around that CD-rom version of the Civil AIP (no offence intended to the civilian ATCOs out there it's just that I am a bit of a luddite).

[radar707]

Rej,

Outside CAS you state the type of service RIS/RAS/FIS, that then becomes the contract between you and the pilot.

When an a/c enters controlled airspace, you must tell the pilot that the service has changed to RCS, that is the service that is being provided. That way the pilot knows exactly what service is being provided and his/your responsibilities under the terms of that service

[Spitoon]

I seem to recall that a few years ago the mil an civil people sat down round a table and agreed common rules and procedures - I think this was when the monika ATSOCAS was coined. Since then the civil way of doing it has changed a little and the mil way, it appears, quite a lot. Maybe it's time to dig out the table again.

[rej]

I cannot agree more that you should state the TOS at all times. I was reading JSP318a today (yes, sad eh) but there is a para in the Annex that refers to Class D (a typical afterthought to us who control in Class D) and it states that controllers do not need to state the the TOS as a pilot enters Class D. However, I bet if something went wrong the book would still get thrown at us.


Its about time that we all came on line - it is confusing for our customers and that is only a bad thing. Trouble is that it seems that us on the coal face only see it as an urgent matter.

[Pierre Argh]

So... Military ATCOs do not give vectors or provide RAS below RVC... and it is alegedly an automatic ticket pull from the ATCEEB if they see a controller doing so!!!

Sounds right by the definition doesn't it?

Questions. How does one provide a PAR or SRA then?

Are we supposed to terminate RAS at the FAF on any instrument approach?

When will we acknowledge that an instrument approach or an SID for that mater provides terrain clearance... and that it only becomes an issue when the approach is broken off. If anyhting other than standard MAP is followed (e.g avoiding action) this becomes akin to an emergency procedure...

[KPax]

I am not sure the service continues under a RAS on PAR. I was told some time ago that you could NOT give avoiding action to someone on the final stages of RAS. Also what if the PAR controller does not have a Radar ticket. Local orders should allow you to vector the ac once on a PAR/SRA.

[jack-oh]

I hate to muddy the waters but the Royal Navy also provide a service called Terminal Control, in which mandatory instructions are given outside of controlled airspace to ac recovering or departing from a RNAS. Under TC the controller is responsible for terrain separation unless a clear and Unambiguous transfer of responsibility is made to the pilot. If Mil ATC can't even have uniform types of service how can we expect Civ and Mil procedures to tally. No wonder aircrew get confused, hopefully when the F15 CM is over they will have a re-think about the whole thing.

[Greebson]

To add to previous replies:
MATS Part 1, Section 1, Chapter 5, Page 12, No 13 Terrain Clearance states:
Controllers are to ensure that levels assigned to:
a) IFR flights in receipt of a RCS
b) flights in receipt of a RAS and
c) flights in receipt of a RIS and receiving radar vectors;
provide adequate terrain clearance for the phase of flight as shown below.

then there is a large table below which for reasons of time I won't duplicate.

Then it states;

Radar controllers have no responsibity for the terrain clearance of, and shall not assign levels to, aircraft:
a) in receipt of a RIS when not subject to radar vectors or
b) operating SVFR or VFR within CAS which accept radar vectors.

It seems pretty clear, as a controller I believe we have more responsibility for terrain clearance than previously indicated in this thread.