Salzburg CIRCLING RWY 33

[Driver 170]

Below is the procedure on how to fly the circling approach to RWY 33. It mentions to use VNAV and VOR/LOC for an ILS. My question is -

1. When would you pilots press ALT HOLD?

2. When would you turn at the SI Lctr, just before or overhead?

3. It says an ILS overlay! But if you select ILS 15 in the FMC why is it an overlay?

The Salzburg Circling procedure must be flown from the SI Lctr, paying particular attention to radius of turn and bank angle requirements.

Note: When the reported crosswind exceeds 10 kts, CAT D Circling minima must be used.

1. Select SI in the FIX page 1, with Radial 125° & Distance 3.5NM
2. Select SBG on FIX page 2, for the Missed Approach procedure,
3. Fly an ILS or LOC approach using VOR/LOC and VNAV with an ILS overlay Approach
selected in the FMC. If flying the NDB use HDG SEL and V/S with the NDB 15 approach
selected in the FMC.
4. Fly the instrument Approach in GEAR DOWN, & FLAPS 15 configuration.
5. Reaching Circling MDA, verify ALT HOLD and set Missed Approach Altitude
6. At SI, follow the 125° Track outbound for D3.5 NM. Reaching D3.5, set Runway Heading,
select Flaps 40 and start a descent on the visual profile (PAPI). Complete the Landing
Checklist.
7. Maintain Vref40+15 until on final RWY 33 and a landing can be assured.

[wiggy]

1. When would you pilots press ALT HOLD?
......3. It says an ILS overlay! But if you select ILS 15 in the FMC why is it an overlay?


Not sure what equipment you are using (simulating?) ...and not familiar with Salzsberg but until someone familiar with ops there comes along I’ll offer a generic answer in line with our SOPs and equipment.

1.I’ll start with the “overlay” query first. with an ILS overlay Approach selected in the FMC. That looks slightly clumsily worded, as I read it it means “select ILS, fly it as an overlay” - in this case you are going to select the ILS from the FMC but are not going to use Approach (APP) mode, you are going to use LOC and e.g. VNAV to fly the profile...more on that in a minute.

2. You are probably not going to press ALT HOLD. More likely you’ll set the circling Minima in the Mode Control Panel (MCP) alt window when cleared for the approach so that you will eventually get automatic altitude capture at circling minima....but...

3. If you do for some reason fly the ILS using APP mode (i.e. coupled to the both localiser and the glide) there is a serious trap. The MCP altitude will not be automatically captured as you reach it, so there is a risk that you’ll descend through the circling minima ...which brings us back to why the overlay...

3. By flying ILS as an overlay you can use a vertical mode which will capture the MCP alt in the descent e.g. VNAV, vertical speed or flight path angle....

There are other advantages to not trying to transition from a full blown coupled approach into a circling manoeuvre, usually ergonomic, but the busting of the circling minima is the main safety reason.

[RAT 5]

#6. HDG 125 you will be blind to the runway. Are you suggesting starting a descent BEFORE entering the +/- 30 degree cone of the centre line or good visual with the threshold? You don't mention a ROD, but it will be more prudent to wait until good visual with the threshold and the intervening terrain before descending below MDA. Circling profiles are normally designed to allow a normal ROD to be selected when intercepting visual finals.

#1. Agree with wiggy that MDA should be elected in mCP and thus ALT HLD will be automatic.

Regarding the SI locator and 125 radial. If you are flying FMC MAP and HDG SEL then one might be tempted to nudge it left and sniff early to prevent overshoot. If you are flying NDB raw data, below MSA, then one can argue you should wait for the needle to fall 90 degrees and then turn back a little more to intercept 125 radial. Turning early on a twitchy needle has caused tears before.

[Driver 170]

WIGGY - I'm using Prepar3D and prosim 737. its for fully built flight simulators.

The problem i have with VNAV on the ILS is that it descends through the DA 1800 thats set in the MCP alt window.

RAT5 - I basically stay level and at 3.5nm, i select f40 and start a 3 degree descend watching the PAPI's and keeping visual with the runway. Making sure also i'm at 500 when i roll out on the runway heading 334.

So regarding the SI locator, i should wait until it starts to turn 90 degrees then?

[wiggy]

WIGGY - I'm using Prepar3D and prosim 737. its for fully built flight simulators.

The problem i have with VNAV on the ILS is that it descends through the DA 1800 thats set in the MCP alt window.



Ok....that certainly won’t happen on a couple of the bigger Boeing’s, I’ll leave it to a 737 pilot to comment if what you see is correct modelling.

[Johnny F@rt Pants]

Having trained SZG in the B737 sim for some years, the best way to fly the approach is in VOR LOC and V/S, adjusting the V/S to mirror the glide slope as necessary. Prior to descending on th ILS, set the minima in the MCP so the the auto pilot captures that altitude, once in ALT HOLD wind the altitude up to the missed approach altitude, this also arms V/S ready for setting up the descent during the final turn.

In a B737 I would personally turn just before the SI to track away from it for the 3.5 nmls prior to turning onto final.

[Denti]

Just disgressing a bit here, but wouldn’t it be more prudent to fly the RNAV visual or even better, one of the RNP AR approaches in todays world?

[RAFAT]

I echo JFP's comments - VOR/LOC & V/S and turn just before the SI. Put SI in the FMC fix page with a 3.5nm range ring and radials 125, 154 & 334. Circling with prescribed tracks MDA would be 2550ft, or DA of 2600ft. What plates are you using that give an 1800ft DA?

[Driver 170]

Just let you guys know this procedure is extracted from an Airfield brief and the company is a famous low cost European operator.

Hi Denti, This company doesn’t approve RNAV RNP

JFP - I’ll carry out that procedure and use V/S ! As for turning before SI wouldn’t this depend on wind direction?

RAFAT - Sorry Cat C 2550ft, don’t know why i wrote 1800. OOPS!

[Driver 170]

Any tips for rolling out on final? Should i insert a RWY waypoint with a height check?

[Smokey Lomcevak]

At our outfit, we're not authorised to fly the RNAV V Visual in anger, despite it not being denoted 'AR' and us having the ability to fly certain radius-to-fix procedures. So it will be an ILS to break in poor weather conditions.

In good weather conditions I find the offer of a visual approach, joining RH downwind, and heavily 'inspired by' the RNAV V procedure works nicely, and keeps out of the way of the departure track. Flown in basic modes/manual, but with the FMC ticking over in the background, we get a nice accurate vertical deviation indicator to the runway. Much lower workload, too.

For circling on the airbus, we couple to the glideslope as normal. I appreciate this refers to Boeing, but in our case there is no backstop to stop us descending though our DA.