Altitude restriction on approach
 

Would appreciate some guidance or reference

Flown a few approaches recently after being cleared the approach and cleared to an altitude below altitude restrictions at the IAF and IF. If ATC clears me for the approach and clears me below restrictions on the approach must I still comply with them? I’ve always thought the answer was an obvious YES but would appreciate any further guidance…

Regards

The answer is indeed obvious.

Hi Vendeeglobes

I'm not sure the answer to your question is entirely obvious. The altitudes essentially come in two forms, the obstacle clearance altitude (OCA) and the procedure altitude that is displayed on the approach plate (the OCA is also sometimes displayed e.g. look at the RNP approaches to Gloucester EGBJ in the UK AIP). The OCA provides the required clearance over terrain and obstacles whilst the procedure altitude is adjusted to factor in a multitude of factors including minimum length of procedure segments and requirements of other airspace or procedures. Where the OCA and procedure altitude are the same or close then you can expect to see a 'not below' line under the procedure altitude.

Where you are being radar vectored, ATC will be working from a radar vectoring chart and I suspect (but can't at the moment provide references) that may allow a descent below the procedure minima. I'll be interested to see how the discussion progresses.

Cheers
TeeS

https://aeronav.faa.gov/d-tpp/2206/00571IL17L.PDF

Let me be sure I understand the question. You’re asking if you’re vectored at 3000ft prior to HERVI and cleared for the approach, if you’re expected to climb to cross HERVI at 4000?

(that’s the ILS to 17L at KMCO if you have trouble opening it)

I thought the scenario in question (when framed in the context of this specific approach) would be as follows:

Aircraft is direct HERVI and above 4,000 ft
Pilot receives clearance to descend to 3,000 ft and also clearance for the approach.
Should pilot maintain at or above 4,000 ft until crossing HERVI or may pilot descend to 3,000 ft before reaching HERVI?

In that scenario, assuming I recognized a conflict, I would have asked for confirmation of HERVI crossing altitude.

In that scenario (USA) if ATC wish you to respect any altitudes between the one you are at and the one you have been cleared to, they will say so: “Cleared approach 17L, maintain 4,000’ (or above) until HERVI”.

On a more general basis, if you’re being vectored and are happy that ATC are not flying you into the ground, then you can ignore the procedural altitudes. Normally a vectored approach will intercept the final course from below the nominal glideslope.

"radar vectors" - their altitudes
"anything else" - procedural altitudes

Interesting subject and very important. May I take the liberty of expanding the Q a little further?
KMCO has been used as an example so to continue with that, whist being radar vectored right hand downwind for 35L and having passed abeam FOBUK heading south you are cleared to 1600’. Would you accept this clearance whilst IMC?

The approach plate attached above was for 17L so I can't have the whole picture. Anyway, I would check the Minimum Radar Vectoring Altitude chart. If in that sector 1600' is allowed (it means - safe), then why not? However due to obstacles east of the aerodrome most probably it isn't...

How many pilots fly with a minimum vectoring altitude chart? Do any modern flight deck displays have the capability of displaying a minimum vectoring altitude chart on the navigation display?

Suspecting the answer is none, do all professional pilots accept that the ATC vectoring altitude is safe and believe that they won't be the next one ATC drives into a hill?

Maybe TAWS is assumed to be adequate protection from controller error.

I was curious about the availability of a minimum vectoring altitude chart for my area. I found a PDF graphic and an XML coordinates file neither of which could I associate with a sectional or low altitude IFR chart.

European LCC, we use the vectoring altitude chart when applicable

If the ATC clears you to 3,000ft, you accept but you maintain 4,000ft, you'll get an earful. If, on the other hand, you are instructed to "cross fix at or above", then maintaining 4,000ft is acceptable.

Some do. Some have a blank stare when suggested, depends on the training. I learned IFR in hilly procedural airspace.

Had this situation into Reus recently where I was ask to "Descend with the procedure, cleared for the approach" and in the same sentence asked to descend to 1000ft below the published platform altitude because some helicopter was holding near the airport (unpublished). Reus as many of you know has terrain to the North. Completely unhelpful.

Where there is one and it’s very hilly, I’ll continuously reference it, especially in Third world countries.

First world airports, I’ll make a note of it in the setup, might mention in the brief,” if we get vectors close in the MVA is xxx”

That very much depends on the clearance,

“DESCEND VIA”
“DESCEND UNRESTRICTED”
“DESCEND AND MAINTAIN”
“DESCEND TO 3000 FEET CANCEL LEVEL AND SPEED RESTRICTIONS’’

Doc 4444 - PANS-ATM reference
6.5.2.4.1 Clearances to aircraft on a STAR with remaining published, level and/or speed restrictions shall indicate if such restrictions are to be followed or are cancelled. The following phraseologies shall be used with the following meaning:

c) DESCEND VIA STAR TO (level), CANCEL LEVEL RESTRICTION(S) AT (point(s)):
i) descend to the cleared level, published level restriction(s) at the specified point(s) are cancelled;
ii) follow the lateral profile of the STAR; and
iii) comply with published speed restrictions or ATC-issued speed control instructions as applicable.

The only reason for this question is because some lazy or trying to be slick ATC is not using standard phraseology.

I had not assumed that the OP's question, or the follow up question, involved a STAR. Did I miss something?

The OP is talking about approach clearances, not STAR clearances.

Absolutely!

Yep use an MRC chart as LIDO calls it but one isn’t published at least not on my EFB hence the Q.

Here is another one cleared ILS across XXXX not below 2000’. The chart shows XXXX with 2000’ at that point with shaded grey below that. Unfortunately it’s ISA +20 so if you cross XXXX at 2000’ you have a significant fly down indication making the SAC a challenge. Any thoughts?
All in the USA no criticism I don’t have the big picture. I’m just looking for best practice