IFR Terrain seperation

[Inverted81]

Hi all...
Quick q to see others take on things after seeing something today.
Aircraft requests to depart IFR at 1000 inside class D airspace. 1000 is below the MSA and RVA levels. Can the clearance be given if the pilot reports they are happy to maintain own terrain sep?

Rule 31 of the ANO seems to exclude this from being allowed.
Interestingly on a visual approach (i.e the reverse of this situation) MATS 1 states that as long as the pilot reports they are visual with the surface and reasonable assurance exists etc etc this can be approved. Nothing appears to be written for the same situation but for a departure.......

[Spitoon]

Rule 29 (d) as was - don't know whether the number has changed in the new Regs (but I am assuming that the rule hasn't) - aka the Minimum height rule, says below 3000ft amsl, clear of cloud and in sight of the surface is OK. In theory I don't even think the pilot needs explicitly to accept responsibility. Also in theory, such a clearance would only be issued following a pilot's request, as a controller I don't think I can do it off my own back (but I can't think of why, specifically, it is proscribed).

[aluminium persuader]

I think this is what you're looking for.

Minimum height
33.—(1) Subject to paragraphs (2) and (3), an aircraft shall not fly at a height of less than 1,000
feet above the highest obstacle within a distance of 5 nautical miles of the aircraft unless—
(a) it is necessary for the aircraft to do so in order to take off or land;
(b) the aircraft flies on a route notified for the purposes of this rule;
(c) the aircraft has been otherwise authorised by the competent authority in relation to the
area over which the aircraft is flying; or
(d) the aircraft flies at an altitude not exceeding 3,000 feet above mean sea level and remains
clear of cloud and with the surface in sight and in a flight visibility of at least 800 metres.
(2) The aircraft shall comply with rule 5.
(3) Paragraph (1) shall not apply to a helicopter that is air-taxiing or conducting manoeuvres in
accordance with rule 6(i).

So basically, the answer is "yes". The proviso is that the flightpath must be at least 5miles from the obstacles on which the MSA is based.

ap

[Report@Boddam]

aluminium persuader

Having read what you've written I would have thought the answer was "yes" even within 5 miles provided they meet the requirements of (d). If the scenario inverted81 is talking about happened when and where I think it did, the pilot would certainly have been able to do this.

[Bol Zup]

I've always assumed the raison d'etre for para (d) is to enable pilots of private/club type aircraft to fly outside controlled airspace at night in VMC below the MSA.
It has never occured to me to issue a non-terrain safe IFR clearance to airliners for example, and I certainly have never received such a request.

[aluminium persuader]

It's not necessarily the case that below the MSA is not terrain-safe. Of course you can't give a clearance that isn't, but the MSA is based on a particluar object and so long as your track will take you at least 5 miles clear of said object and you'll be at least 1000' above any other object within 5miles of your track, you're complying with the IFR rule.
Must point out, though, that we're talking heights AGL here; and unless you're departing from a high airfield & routeing over lower ground it would be hard work flying-wise. Never had anyone ask for such a clearance!

But that's all bad wx-wise. There's also, as Spit said, para (d).

[bookworm]

I think you may be looking in the wrong place.

Within controlled airspace the IFR aircraft must fly in accordance with its ATC clearance, and the conditions for issuance of the clearance are likely to be more limiting than the Rules of the Air, which permit any level with surface contact and a vis of > 800m.

MATS Pt 1 S1 Ch 5 para 13 deals with minimum levels under radar (1000ft above anything with 5 miles of the aircraft or 15 miles ahead, with exceptions).

MATS Pt 1 S3 Ch 1 para 9.1 deals with minimum levels for arriving aircraft under Approach Control (above MSA) though

If a pilot is flying at, or has requested, a lower level or has confirmed that he is in a position to accept an air traffic control clearance at a lower level; a reminder of the highest sector altitude should be issued.

I can't, however, find anything for departing aircraft under a procedural service.

[Bol Zup]

"It's not necessarily the case that below the MSA is not terrain-safe. Of course you can't give a clearance that isn't, but the MSA is based on a particluar object and so long as your track will take you at least 5 miles clear of said object and you'll be at least 1000' above any other object within 5miles of your track, you're complying with the IFR rule."
Yes, but the rule states pilots must be +1000ft above highest obstacle within 5nm UNLESS they are below 3000ft, clear of cloud, sight of surface etc.

[aluminium persuader]

Has anyone else noticed that we're all saying the same thing?! :\