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Visual Approach best practices


KirkR
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I find that a visual approach in the sim is not often so easy due to things like resolution, not having side windows, and just task saturation for a single pilot process.  Yet on online ATC we need to be able to do these in a proficient manner.  As I have been practicing these (CL60), I wanted to share my process(es), hoping to generate some feedback from the actual Challenger pilots on the forum who are also using the sim (and others as well).

Scenario 1 (IFR flight, VFR conditions @ airport, ATC vectoring for visual apch, not a familiar airport, ILS not in operation):

- Select Visual Approach in FMS and possibly adjust the distance (defaults to 5 nm).
- arm NAV and APPR
- ALT set down to the ground (I believe this is req'd w/ "Visual Approach" in FMC)
- VNAV armed (is this req'd for the simulated GP to display in the "Visual Apch" mode?)
- AP and ATS deactivated

Practice coming in from various directions.  Lateral and vertical guidance are displayed (as an aide/reference but not "flown")

Scenario 2 (same as 1, except ILS is in operation

- Select the ILS approach in FMS (rather than Visual Apch) and use it as a reference, similar to Scenario 1
- rest is the same except ALT does not have to be set down to the ground, and VNAV does not have to be activated

What techniques does the CL60 community use for visual approaches to unfamiliar airports when under ATC guidance, with the CL60?

 

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Kirk,

The visual approach functionality is one of the best things about this airplane and we use it all of the time. I'd have a hard time giving it up.

If the ATIS is advertising visual approaches, we will select the visual approach in the FMS. Most of the time we will select 3nm for the RX. Assuming we are more or less 'straight in' when we're cleared for the visual approach, the PF will ask for 'direct to the RX'. The PM will make the selection in the FMS, verify with the PF that it is correct before execution, and when that is complete, the PF will typically ask the PM to 'spin [it] to zero' , meaning the PM sets the ALT selector to zero. The AP is typically on at this point, and the PF  sets up the FCP by selecting APPR and VNAV. The PF will also check and verbalize that the computed TOD is 'in front' of the airplane to ensure the airplane isn't already above the computed path. If it is - then the PF will have to select a vertical mode to get the airplane heading downhill to an intercept of the PATH.   (The timing of all this varies considerably depending which way we are approaching from, what altitude we are currently at, etc.)

Quite often when an airport in the US advertises the visual approach - ATC may still reference an IAP waypoint as part of the initial approach; typically the GS intercept if the runway is served by an ILS. For this reason we always insert that waypoint before the 3nm RX  - and we input the IAP crossing altitude.  Quick example: 

KBDL is advertising visual approaches to runways 24 and 33 on the ATIS. Today we are going to Signature Flight Support and the winds are light and variable - so we brief that we will request runway 33 when checking in with BDL Approach. We setup the FMS with the visual RW33, with a 3nm final - ands insert HOMEY at 1800ft. (HOMEY is the GS intercept for the ILS 33). Upon being handed off from Boston Center to BDL Approach, we check-in with the ATIS and request 33. We're given direct HOMEY for the visual 33.  This happens quite often, and is why we are prepared to reference the primary underlying approach even though the ATIS is advertising visuals. If we're somewhere we don't fly often - this can surprise you if you aren't prepared and don't know the IAP waypoint.

From here at some point we'll be asked if we have the airport in sight or the preceding aircraft - and if we do - we're cleared for the visual 33. We setup per the above and from here it's just automation and energy management. The AP is on - our eyeballs are outside - we have automated lateral and vertical guidance to a stabilized visual approach. Better than an ILS in the sense that there's no NAV to NAV transfer and a go-around already has us selected to FMS source.

Briefing for the missed when expecting the visual would take into account traffic pattern altitude and direction for that runway as well as some situational awareness on obstacles on the upwind and close-in to the airport.

Thoughts on your scenario 1 outline vs IRL: 

- Select Visual Approach in FMS and possibly adjust the distance (defaults to 5 nm). [Most typically use 3nm IRL, more if required by circumstance]
- arm NAV and APPR [pick one - but can't do both - we leverage APPR - schoolhouse suggests NAV for some bigger picture consistency (save that for later)]
- ALT set down to the ground (I believe this is req'd w/ "Visual Approach" in FMC) [ALT set to zero or field elevation in order for airplane to descend at PATH intercept]
- VNAV armed (is this req'd for the simulated GP to display in the "Visual Apch" mode?) [VNAV armed with ALT set to zero for airplane to descend on PATH]
- AP and ATS deactivated [Up to you - depending on circumstance - Automation has benefits you progressively forfeit as levels of automation are reduced - but it's good to keep hands and skills sharpened. Be smart with your choice based on situation; don't try to be a hero handflying in a busy terminal area with lots of traffic, lots going on]

 

Thoughts on your scenario 2 outline vs IRL:

This would be what we'd describe as 'a visual backed up by the ILS' where the jet will nav to nav transfer from FMS to LOC.

- Select the ILS approach in FMS (rather than Visual Apch) and use it as a reference, similar to Scenario 1 [Yes]
- rest is the same except ALT does not have to be set down to the ground, and VNAV does not have to be activated [Correct - GS will capture similar to VGP regardless of ALT selector - and you can set your pattern altitude - or briefed go-around altitude upon GS capture]

I much prefer scenario 1 as it is cleaner - but scenario 2 is handy when it's VFR yet the ATIS advertises an ILS or IAP - and therefore that is what you're setup and prepared/briefed for. At some point on the approach you may press the situation and announce the field in sight - and maybe you'll get the visual clearance -or perhaps ATC asks you and reply you have it in sight and get the visual clearance. Since you're already setup for the ILS - it becomes a visual backed up by the ILS - no more messing with the box close-in - and that's a good example of when you'd use Scenario 2.

 

Considerations:

  • If it's our first time to the airport, or we haven't been there in quite some time - or it's an airport with obstacles/terrain /  'sh*t to hit' or it's dark, we may just ask for the IAP despite the good weather. That pushes us more into 'scenario 2'. 
  • Home base - sea level airport - no terrain, minimal obstacles = Scenario 1.
  • If approaching the airport from opposite side of airport - example: Visual 33 KBDL and we're coming from the NW and being vectored onto a left downwind to RW33 = Setup per scenario 1 except put the RX at 4nm, if on radar vectors and flying in HDG mode - perform a Direct To Intercept to the RX but enter a base course in Right LSK 6 spot on CDU. For inbound course of 330, this would be 060. Once cleared for the visual approach - selecting APPR (or NAV) + VNAV + preselect to zero = the airplane will fly a beautiful left base to final and because of the 4nm RX - you're ensuring a more stabilized rollout before 1000' above the airport.
  • If approaching airport from straight in side of airport in HDG receiving radar vectors - perform a Direct TO Intercept to the RX and 'extend the line' through the RX by inputting the final approach course in Right LSK 6. For example with RW33 = 330. Then when cleared for the approach you select APPR (or NAV) + VNAV + preselect to zero = the airplane will intercept the extended centerline for the visual approach.
  • ALT selector to zero vs field elevation will change the altitude alert dynamic. Some pilots prefer field elevation for this reason. 
  • If you're expecting and or subsequently cleared for a visual approach from scenario 1 or 2 - understand you were not cleared for the ILS or other IAP. Therefore in a go-around scenario - ATC is not expecting you to fly the IAP MAP. I've flown with a lot of professional pilots that will enter into scenario 2 and brief 'visual backed up by the ILS' and proceed to brief the IAP MAP.
  • NAV vs APPR: The schoolhouse has suggested that to keep our heads straight between the different types of approaches and FCP selections - for the visual approach they have recommended NAV/VNAV

 

 

Edited by VictoryAJ
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In relation the the final consideration point, re: schoolhouse recommendation of NAV/VNAV vs APPR/VNAV - i recall the explanation being one of consistency. Approaches flown to a DA with Pre-Select set to MA-ALT and VERT LABEL of GS/GS or GP/VGP = APPR. In comparison - when flown to an MDA on PATH/VPATH we'd select NAV. It's hard to remember the appropriate modes - so to keep it consistent = NAV/VNAV because the visual approach will go to your MDA of field elevation or zero and it will be via a VPATH.

 

Old habits die hard. >15 years of APPR/VNAV makes it a hard habit to break. They both function identically.

 

IMG_5F8E3AA466A5-1.jpeg.2f744df47f95af6e9d9c32d528247993.jpeg

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The combination of the fully functional CL60 simulation, and the above perspectives and details - are of high value and lay out a very nice set of training scenarios.  And in an affordable manner (I haven't gotten any fuel or maintenance bills from flying the Hot Start CL60 yet.

Indeed I will follow up after exercising these scenarios further based on the guidance.

Once again, Thank You!

 

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Posted (edited)

@VictoryAJ,

***. Edited - looks like I figured this out, that I needed to get my altitude down below 2600 on the downwind (southward) leg in order to get TOD out in front enough (on the base leg) to activate.  Staying at 2600 until the NAV guided turn onto the base, even though TOD was a little further down base, evidently was not sufficient.  Maybe the aircraft was not "established" on the base leg on which TOD was shown, sufficiently enough to be able to have the aircraft initiate the VNAV descent.

*** Text below was entered before the above was determined in a subsequent flight/test.

A follow-up question for you after practicing the visuals today.  Coming in to KFNT (Flint, MI) from the opposite direction (from the north), vectored to downwind for visual approach to 36, I set RX @ 4nm, DIR to the RX @ 095 (approach crs is 005), RNAV apch (no ILS).  So this is NAV-NAV per our dialog above.

My question regards VNAV and TOD.  My altitude coming into the downwind is 3000 which causes the TOD to be a little west of where I will enter (turn into) the 095 DIR-TO the RX, so VNAV does not initiate (yes I did spin to 0 proactively).  So I have to push it down using VS.  Did I do something incorrectly or do I need to get down to pattern altitude sooner?  Sometimes ATC may not get you down as quickly as you would like, their own task saturation possibly.  Note that I did additional tests and even getting down to 2600 on the downwind leg, with TOD showing as after turning onto the base, it still did not initiate the descent w/ VNAV.  So obviously something that I'm not setting up properly.  I did not include JORDI and 2400 in the plan as the base to final turn is 4nm which is about 2100 ft fyi.

Possibly this is a scenario where APPR would be used after the aircraft turns onto base?  But APPR may not deal with the 90 deg turn so well?  So this probably isn't the solution?

Thanks for guidance.  This is fun stuff to practice.

 

Edited by KirkR
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Sorry for the delay. I did some testing last night at KFNT.  I put the jet on a 5nm left downwind for 36 at 3000 ft. FMS was setup for the visual RW36 with a 4nm RX, and a 095 base leg.  When I was abeam the field at 3000 I set the ALT Preselect to zero, armed NAV and VNAV. The TOD was depicted in an odd place - off on it's own aligned with the base course. I'm not sure that is how we see it IRL, but it's now on my list to validate. Anyways, shortly after passing abeam the field the vertical path appeared and she captured the vertical and lateral paths, flew a nice descending base and rolling out near the RX.

 

I'm unclear on your quote here regarding the RNAV and NAV-NAV. Please verify how you had the FMS setup for this:

 

A follow-up question for you after practicing the visuals today.  Coming in to KFNT (Flint, MI) from the opposite direction (from the north), vectored to downwind for visual approach to 36, I set RX @ 4nm, DIR to the RX @ 095 (approach crs is 005), RNAV apch (no ILS).  So this is NAV-NAV per our dialog above.

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I think my comment was not correct for two reasons.  I meant NAV-VNAV, but I believe APPR-VNAV could be used as well.

So you also saw the TOD off to the right.  I'll run through it again to see if it captures the vertical even though TOD is depicted off to the west of where the turn to base occurs.  

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Posted (edited)

Ok, I reflew just as you described, 5nm abeam of KFNT (to the west) downwind, indeed vertical nav did initiate (as soon as the aircraft was established on the 095 int crs to the 005 final crs).  I believe I may have assumed it was not going to descend given that TOD was "behind" the aircraft when turning to the 095 int crs and so I must have previously switched to VS mode.

Edit:

I just tried this using a 3NM RX, 3000 ft abeam on downwind.  I found that I needed to get the altitude down on downwind (2400) and get the speed down as well, and then VNAV worked as designed.  Trying it from 3000 on downwind did not work.  But from 2400 did.  I think it's a matter of tuning between altitude and speed.  I can tell if it's going to work based on how far TOD is out to the west on the intercept course.  the further out it goes, the less likely it's going to be able to bring the plane down as needed.

Will be interesting to see if the TOD is positioned this way in a real life scenario.

This brings me to an additional question for you:

What is your speed management profile for this specific approach?  I'm still learning in this area.  I would reduce from my descent speed to 180kt w/ 20deg flaps @ 3000, then 30deg flaps and 160 just before the turn to 095 (base), then full flaps and 150 before the turn to 005, dropping the gear during the turn and reducing to landing speed (Vref+X).

What if you're on the tighter 3nm RX with a turn from base?

Kirk

Edited by KirkR
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As I'm approaching the abeam point I'm clean at 200 knots. Passing the landing threshold - flaps 20/180 knots. As the jet is about to capture the VPath is a good time to configure flaps 30 / 150 knots. As the path captures and you're heading downhill - get the gear down.  As the jet turns final and rolls out the flaps are moving to 45 but I'm not slowing below 140 until rolling out on final - at which point I'd like to get to Vref + wind correction and be stabilized asap.

We'll use a 3nm RX at our home field approaching from the downwind - but keep in mind this has you rolling out on final below 1000ft. Typical company SOP for visual approaches requires us to be stable no later than 500 above - so this compresses the profile quite a bit. 3nm wouldn't be something to leverage at FNT approaching from the north unless you were very familiar and conditions are right. Manage your risk appropriately, make good decisions, don't get too comfortable or become complacent and remember - it's your blind spots that will kill you. 

The 3nm RX is most typically used when we arrive relatively straight in.

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Thanks for the added speed profile and RX (runway extension) perspectives.  For sure 4nm vs 3nm is a pilot decision (not an online ATC one) in terms of executing the visual approach, and flying the sim jets without any "feel" and with more limited "visibility" to the environment would further suggest that 3nm for other than straight in is not an appropriate RX distance for most of us in the sim world.

Thanks again!

 

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  • 2 weeks later...

I am pasting in a link to a video that demonstrates the visual approach with automation assist in the Challenger.  Taking off from KMBS (Saginaw, MI), very short flight south to Flint, MI, enter downwind and use NAV+VNAV as an automation assist with a 4nm RX (runway extension) from the FMS to aid with the approach.  I hope this is of value for the community.

 

 

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Sorry guys, you lost me on the LSK6R for the base leg intercept course? In which MCDU screen do you use the LSK6R? Can't make it out in Kirk's video 

Got it, it's in DIR to the RX fix, than on that screen adding the INTC course in LSK6R

Edited by FYG001
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