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Driver170

Circling to land.

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I'm finding i'm overshooting the centreline once i turn final, i believe i'm too close to the runway, but i don't know what else to correct for. I'm following my set of SOPs.

 

In a nutshell

 

1. L/R 45* for 20sec and (+/- wind component) my TWC is 7kts so i start the timer for 4 seconds.

 

2. Turn downwind once time is up

 

3. Abeam landing threshold, start timing. (3 sec/100ft +/- wind) eg 1200 agl = 36 sec and minus half my TWC which is 17kts this gives me a timing of 28 seconds abeam the threshold.

 

4. Turn base - When TIME OUT is noted proceed as follows:

 

 Keep the landing threshold and PAPI’s in sight

 Turn the MCP HDG to the runway heading

 Call for landing flaps

 Select MCP speed to V Fly

 Descend on the PAPI’s

 Complete the landing checklist

 Disengage the autopilot, and disengage the autothrottle at the same time

 

 

5. And Land.

 

 

But i'm still overshooting the centreline. I have even used AOB 30* and set landing flaps before the rollout on base. It seems like 20 seconds and TWC is to little a time.

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But i'm still overshooting the centreline. I have even used AOB 30* and set landing flaps before the rollout on base. It seems like 20 seconds and TWC is to little a time.

 

Fly a traffic pattern. Keep airport in sight. Done.

 

Don't overcomplicate it.

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Are you correcting appropriately for drift on the downwind leg (i.e. are you being blown tighter by a crosswind?). It might be worth looking at the flight track via either the FS map or by using some sort of software that will give you a graphical representation of the flight track overlaid on to Google Earth or whatever to see what shape your circuit is...

 

What speed/config are you in turning downwind/final? Obviously the timings will be based on maintaining a particular speed, otherwise you'll end up in a different place if you're faster or slower than whatever the timings were calculated with.

 

To be honest, it's almost impossible to reliably judge the final turn in FS because of the visual limitations of the sim, so I wouldn't beat yourself up too much.

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Fly a traffic pattern. Keep airport in sight. Done.

 

Don't overcomplicate it.

 

CTL thats what i'm doing. It all works out if i stick to 20sec but its that TWC that shortens my 45* left turn keeping me closer to the runway.

Are you correcting appropriately for drift on the downwind leg (i.e. are you being blown tighter by a crosswind?). It might be worth looking at the flight track via either the FS map or by using some sort of software that will give you a graphical representation of the flight track overlaid on to Google Earth or whatever to see what shape your circuit is...

 

What speed/config are you in turning downwind/final? Obviously the timings will be based on maintaining a particular speed, otherwise you'll end up in a different place if you're faster or slower than whatever the timings were calculated with.

 

To be honest, it's almost impossible to reliably judge the final turn in FS because of the visual limitations of the sim, so I wouldn't beat yourself up too much.

 

No correction for drift on downwind. I'll check that out and see what my flight path is.

 

Before turning 45* left from the instrument runway and 4nm from the threshold i set gear down, f15

 

I've gave myself 2 Choices – diverge slightly downwind and slow down around finals. being in the landing config as i roll out as there is not a lot of space to lose 1200ft 25 AOB and even tried 30* that should be enough!!!

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CTL thats what i'm doing. It all works out if i stick to 20sec but its that TWC that shortens my 45* left turn keeping me closer to the runway.

 

I know what you're doing.

 

What is the point of a CTL procedure? It's there to put you on the opposite end of the runway, or onto another runway. It doesn't need to be a crazy scientific and mathematical process. Maneuver to the other runway. Keep the airport in sight. Done.

 

What you're seeing are commonly used guidelines/techniques.

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Terrain around the airport and a straight in approach is a no go.

 

Nothing scientific here, its pretty basic procedures that pilots use for a CTL. Few minuses and pluses to get where you need to be.

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Vernon, the Nav Display includes a turn path predictor (looks like a dog's tail wagging) that gives an indication of the projected flight path for a given angle of bank.

 

Without getting fixated on this instrument, and using it with reference to the runway extended centreline, it can be used to give you an idea of whether your turn is going to roll you out on centreline or not.

 

Bottom line though: Circling to land is a visual maneuver, and the techniques you've outlined are designed as guides only. If you get too fixated on timing the maneuver rather than actually flying it, you will usually end up in a pickle!

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Extend outwards a little bit. You should have a ton of room. CTL require 2.7-3.3NM of clearance of obstacles depending on the MSL you are landing at for CAT C approaches.

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Vernon, the Nav Display includes a turn path predictor (looks like a dog's tail wagging) that gives an indication of the projected flight path for a given angle of bank.

 

Without getting fixated on this instrument, and using it with reference to the runway extended centreline, it can be used to give you an idea of whether your turn is going to roll you out on centreline or not.

 

I'm aware of that tip. Great tool yes, i use 20nm range gives you 2 or those white lines and then i adjust bank selector to get the trend on the threshold. Great tip!!!

Extend outwards a little bit. You should have a ton of room. CTL require 2.7-3.3NM of clearance of obstacles depending on the MSL you are landing at for CAT C approaches.

PANS OPS protected area for circle to land approaches is 4.2nm ring around both thresholds

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Nothing scientific here, its pretty basic procedures that pilots use for a CTL. Few minuses and pluses to get where you need to be.

 

Yes. That's what I've been saying this whole time. You were the one dragging math and various components into it. That would be suggestive of mathematical or scientific approaches to an otherwise simple concept. As I've been saying, and the others have chimed in:

 

Move airplane to line up with other runway.

Done.

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Yes. That's what I've been saying this whole time. You were the one dragging math and various components into it. That would be suggestive of mathematical or scientific approaches to an otherwise simple concept. As I've been saying, and the others have chimed in:

 

Move airplane to line up with other runway.

Done.

 

0

 

I follow this

 

8.19 Circle to Land Approach - SOP

 

Timing is started when steady on track or wings approximately level whichever is sooner. Both pilots will time the leg. PM selects PROG page 2 at this point. Wind effect must be factored into the duration of this leg by reducing/increasing the still air time of 20 seconds by an amount that is equal to half the TWC/HWC. TWC/HWC can be seen in the PROG page 2 in the FMC. HDG is used to ensure that the required track is maintained. At Time Out turn onto the downwind track using HDG to adjust for wind.

 

So you see? Timing is needed.

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So you see? Timing is needed.

 

No. It really isn't. If your SOP states it, then fine, do it, but don't make it more difficult than it needs to be otherwise. I know you really like the fact that you have a RW operator's SOP, but it's one of several hundred. Personally, I find it to be completely counter productive to my primary mission: keeping the field in sight (remember, the CTL is a VISUAL maneuver - if you lose the vis, you get to shoot that approach again) and putting the plane safely on the ground.

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No. It really isn't. If your SOP states it, then fine, do it, but don't make it more difficult than it needs to be otherwise. I know you really like the fact that you have a RW operator's SOP,

 

Its not about my SOPs. I've searched about and found on PPRUNE that every pilot uses that simple technique to get around the airfield. Of course its a visual manoeuvre and its the PM to keep an eye ball on the airfield environment or lights in sight throughout the approach. This approach is certainly a numbers game, as well as autopilot and manual flight!

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Its not about my SOPs. I've searched about and found on PPRUNE that every pilot uses that simple technique to get around the airfield. Of course its a visual manoeuvre and its the PM to keep an eye ball on the airfield environment or lights in sight throughout the approach. This approach is certainly a numbers game, as well as autopilot and manual flight!

 

No. Please stop making these wild assertions without having flown an aircraft enough to make them. The PF needs to have their eyes up and out. Why do you think the PNF calls speeds during the TO roll and on approach?

 

It's only a numbers game if you want it to be. If you want to make it complicated, go right ahead. If you'd like to worship everything that comes out of pprune, then that's fine, but you have to keep in mind that the site is also subject to a bunch of armchair pilots making half-cocked assumptions about flying. Meanwhile a bunch of them haven't actually flown at the level they're claiming to have flown. Sure, many are probably speaking from experience, but a good number of others are just bleating the same info because the other people said it.

 

Do yourself a favor: spent a day up at an airport FBO talking to the pilots there. I can guarantee you that you'll get better answers, particularly because none of them can hide behind a keyboard. I'm also relatively sure very few of them are going to give you a numbers-based rule of thumb for circling procedures.

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I'm only saying what i have read and also been told by a few pilots that fly the NG and the bus, that they use the stop clock and by all means it is a visual manoeuvre YES, but they do use the stop clock for the timings.

 

Maybe FBO or whatever that is in the USA i assume? Maybe they don't use timings but certainly in Europe a vast majority of them do. I have even seen a video RYR on a private youtube account using the stop watch m, maybe as backup? I don't know. But they certainly use it.

 

I'm not claiming ALL pilots use it, its down to SOPs and whats in the Ops manual A what you follow.

 

I'm only hear to find out about my way of doing it not yours.

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Hi Vernon.

Good to see you attempting the dreaded Circle!

With regards to the operators SOP’s you follow I think I know where you’re going wrong.

 

 


1. L/R 45* for 20sec and (+/- wind component) my TWC is 7kts so i start the timer for 4 seconds.
 

 



Firstly make sure if you’re not already to fly tracks and not HDG’s

After breaking off the approach L/R 45 wait until the wings are level then start your timing. It’s 20sec in still wind conditions (+/- Half TWC). So if you have say a 10kt TW (use FMC PROG PG2) take half of that (5kts) and subtract that from 20. So you’d fly your 45 degree track for 15s before turning downwind.

Once downwind a really neat way to see if you’re too close to the runway (or too far) is to set the ND range to 5nm, the aircraft symbol should roughly be outside the 1.25nm circle.

The rest I think you pretty much have and all the other points provided are excellent. There is no problem overshooting the centreline, use the trand vector and 30 AOB if you have to, so long as you're within the 4.2nm PANS OPS protected area and you don't descend below the circling minima until established on final you'd be safe and legal!

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Hi sam.

 

Its a pretty basic procedure to follow but i'm sure its more difficuilt in the real life i bet ;)

 

Firstly make sure if you’re not already to fly tracks and not HDG’s

 

Ok so, you mentioned to fly tracks? Does that mean wind corrected heading i assume?

 

Once downwind a really neat way to see if you’re too close to the runway (or too far) is to set the ND range to 5nm, the aircraft symbol should roughly be outside the 1.25nm circle.

The rest I think you pretty much have and all the other points provided are excellent. There is no problem overshooting the centreline, use the trand vector and 30 AOB if you have to, so long as you're within the 4.2nm PANS OPS protected area and you don't descend below the circling minima until established on final you'd be safe and legal!

 

What circle is the 1.25nm? Am i creating that in the fix page or is it already displayed on the ND?

 

Ok i will give it another shot, but i do overshoot quite wide and thats with 30* AOB and full configured before the turn on finals

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Also sam do you use V/S to initiate the descend to finals when turning? Roughly 300 fpm?

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Ok so, you mentioned to fly tracks? Does that mean wind corrected heading i assume?

 

 

What circle is the 1.25nm? Am i creating that in the fix page or is it already displayed on the ND?

That's it, you should have the ND to set Track Up so all you have to do is give yourself a heading to match that whatever track you need.

 

The ND has four circles no matter what range you set on the EFIS, each circle represent a 1/4 of the selected ND range. So it you select the range of 5nm each circle represents a distance of 1.25nm from your aircraft. When downwind you want the runway just to be outside the first ND range ring (approximately 1.5nm from the runway). This gives you a ball park picture as to whether you're too close or too far from the runway so you can plan ahead and work out if you'll need more or less bank to roll out accurately on final.

 

 

Also sam do you use V/S to initiate the descend to finals when turning? Roughly 300 fpm?

 

Maintain the circling minima until you're on final and (hopefully if there's PAPI's) wait until you see two reds and two whites, disconnect, recycle flight directors and descend with the PAPI's.

 

Remember this isn't an exact science so if you slightly overshoot or miss your timing by a few seconds no big deal!

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That's it, you should have the ND to set Track Up so all you have to do is give yourself a heading to match that whatever track you need.

 

Ok slightly scratching my head - Am i just setting the heading bug at ALT ACQ in my case Left 45* 105 heading or am i correcting that for drift cause of wind?

 

Maintain the circling minima until you're on final and (hopefully if there's PAPI's) wait until you see two reds and two whites, disconnect, recycle flight directors and descend with the PAPI's.

 

Remember this isn't an exact science so if you slightly overshoot or miss your timing by a few seconds no big deal!

 

When i turn on final i'm always seeing 4 white

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Ok slightly scratching my head - Am i just setting the heading bug at ALT ACQ in my case Left 45* 105 heading or am i correcting that for drift cause of wind?

 

A TRACK is a course that already corrects for wind...

 

 

 


When i turn on final i'm always seeing 4 white

 

Turning too early. As I've been saying this entire time, start looking out and eyeballing things. The best computer you've got is in your head. Sometimes, overly-precise is actually a bad thing...think SLOP.

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The ND has four circles no matter what range you set on the EFIS, each circle represent a 1/4 of the selected ND range. So it you select the range of 5nm each circle represents a distance of 1.25nm from your aircraft.

 

I've just selected 5nm range on the ND and those circles are 2.5nm sam? Not sure what is going on?

TRACK is a course that already corrects for wind...

 

But will i not need to calculate my drift angle?

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But will i not need to calculate my drift angle?

 

You can if you really want to, but I don't see why. Turn toward the heading. The ND will display the track line and heading carat. Adjust the heading such that the track line is straight down the track you need. Remember that timing starts wings level.

 

...or eyeball it and save yourself the massive headache you're creating here.

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You can if you really want to, but I don't see why. Turn toward the heading. The ND will display the track line and heading carat. Adjust the heading such that the track line is straight down the track you need. Remember that timing starts wings level.

 

...or eyeball it and save yourself the massive headache you're creating here.

 

Ok kyle cheers, i have turned to my heading 105* and the trackline is at TRK 110 MAG.

 

So i'll turn my heading 100 to make my track 105

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