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Guest Divergent Phugoid

VOR/VORDME/NDB/Visual approaches

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After flying in FS for years now, I thought I ask how others do it, maybe somebody can tell me how it's done in real life:I'm talking about VOR/VORDME/DME and pure visual approaches.Smaller planes are easier, I know, but I'm interested in the heavy iron since that's what i fly most of the time.Let's take my latest favorite for instance, TNCM. The approach is mainly visual, but there's a VORDME available.It's convenient to take a plane like the 737NG or the LDS767 where the ND can display that nice arc which I can take as a reference, but I often take planes with very basic instruments (e.g. DF727).I'm not a pro in maths, and my brain must somehow have an allergy calculating numbers. So, the basic question is how to properly fly such approaches.My experiences are that in theory, if you have basic data available (such as distance and speed), many charts even depict the descend rate in one corner of the map. And, there are some formulas to mace these calculations by hand (I wrote a small Excel macro which performs this as well).But in practise, things always look different. I take my TNCM example here: after flying the 306 or so radial outbound, it's usually difficult to tell the exact point where to start the left turn. Either I'm at almost 10NM wehn 90deg to the radial, or I turn too early and too sharp, trying to keep an average sink rate of I-don't-know-how-many-feet-but-around-300-to-500-look-okay. The turn itself to the final approach course is an adventure by itself: it's almost impossible for me to judge a correct bank angle, so I look at the instruments (RMI, VOR needle) how much to turn and when.So, up to this point, the plane may look stable and smooth when watched from outside, or maybe from a passenger's seat. But when looking at the instruments, it's a permanent fight with alternating sink rates and bank angles in the quest to fly the path as close as possible (i.e. turns are almost never circular curves since the angle fluctuates because I need to adjust speed, bank angle and pitch constantly, no matter what plane I take).Then comes the final approach phase: I usually try to follow a VASI or such devices, but sometimes it's hard in the big planes because of the speed management, slow engine spool up etc. Usually, I come in too high more often than too low (try to avoid this 'cause I'd #### in my pants in real life when I'd know I'm too low, so I try to make this a little more realistic for me ;-) ). But it's only 1 time out of 10 when I finally manage to do an almost "perfect" landing after practising dozenz of times.The approach itself as well might look smooth from outside (tower views at least look great), but from the inside, its a constant fight with speed, altitude and the effort to not miss the runway by permanently correcting the course.I do my best to make all maneuvers as constant, slow and smooth as I can, but often enough I find myself getting the plane out of a 30deg bank in a mere 2 seconds.I don't consider myself an extremely bad sim pilot, at least I can get them all down in one piece and without damage (i.e. no runway misses/overshoots/nose gear touchdowns, and my vertical speeds when the main gear touches ground are always between 100 and 400 feet. Any, I'm aligned with the centerline up to a few degrees most of the times, and braking/reverser usage are as normal.As I said, when watched from outside, the maneuvers look as if aou'd look a real plane in the sky. But I know from my pilot's perspective, it's a completely different story.Now we come to the central point: ILSs are much easier to fly becauseof the guidance you have. But approaches like at TNCM aren't, you have a straight leg with a turn, followed immediately by the final approach leg, and all that requires a constant descent.So, when I do TNCM, I could hardly calculate with a distance (remember the varying turn radii etc.), let alone speed which goes from about 200 kts down to as low as 125 kts in some cases (i.e. I have a constant speed drop all the way during descent; how would I calculate with that?). In the end, I fight with speed to either stretch the final phase 'cause I'm a little low, or I touch down so late that I have a hard time getting the plane to stop wile on the concrete.As I said, ILSs are different, I have fewer problems at the old VHHH than I have at TNCM, LPMA etc.After all, it's fun for me, that's what counts in the end. But I wonder if I'm the only one having this kind of "problems"...Andreas

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I find that aslong as I have the relevent charts for any particular approach I dont have a problem.I also like to fly TNCM, LPMA and SBRJ in the "larger" stuff, and find that the prescribed approaches give you plenty of time to get into the right landing config.One thing I have found was not trying to "chase" the descent to much, but just make small corrections, I also make sure I am getting configured early, so at TNCM even before the turn on final I am at a slow enough speed with some flap extended, in fact, I reckon I get the plane configured far to early than IRL.Just try not to rush it and do too much in one go.Dan.

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Maybe my story makes you think I'm having a nervous and hectic approach procedure.Quite the contrary is the case: everything is calm, I don't sweat (okay, at least a bit), I can handle it al without getting stressed too much (need to say here that I mostly practise approaches, so when I'm doing my 2-3 hrs of simming, I have dozenz of them; after the years (started with FS4) I had hundreds and hundreds...).What I'm concerned about is the way I do things. As I said, I need to control the plane during approach, which may look great from outside, but is a procedure of constant corrections in speed, pitch and bank.Not having an ILS available (and sometimes not even a VASI), I wonder how people do their visual approaches. Judging by looking at the runway perspective?I for my part try to get the main wheels down close to the two thick bars on the runway (don't know their correct names, something like touch down zone?).Of course, I could prepare the plane in a configuration suitable for final approach some 30 NM away, but I follow what I've read somewhere often: speeds as high as 200kts on the glideslope, keep gear up and clean configuration as long as possible, don't open throttles too much.i could ease the task by going to landing configuration early. The way I do things means high and variable speeds (200 down to 130kts), constant config changes (flaps/gear deployment with the resulting pitch corrections). And I try to use only the minimum thrust needed.That all, and I try to aim the two thick bars. I can't imagine someone can do this by only looking at the runway: sooner or later you need to add lots of thrust 'cause the flaps eat your speed, or you need to resist the urge to dive for the runway 'cause you're too high. But to make all that in a fluent manner seems very difficult to me.Need to say that I look out of the window most of the time during approach, which seems okay even in real life.But I try to imagine how I'd do it if I were in a real plane. I'd be extremely/over-cautious (got only 1 life), so I'd do everything on the safe side. That means to make absolutely sure that instruments are okay, that the runway is ahead of me and that I won't miss it and ground the aircraft.Andreas

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Approach speeds can vary wildly IRL to suit many different conditions, I have seen SAAB2000's screeming in and shooting an ILS approach at 200+kts, on the flip side I have also seen big jets ambling in very slowly, obviously this reflects what is needed at the particular time."As I said, I need to control the plane during approach, which may look great from outside, but is a procedure of constant corrections in speed, pitch and bank."This is what I meant by not trying to "chase" the approach to much, I have found that by trying very hard to "chase" the approach you get in more trouble, just make sure that you are trimmed correctly, and make small inputs on the throttle to control your descent rate, and small pitch changes to alter your airspeed." could ease the task by going to landing configuration early. The way I do things means high and variable speeds (200 down to 130kts), constant config changes (flaps/gear deployment with the resulting pitch corrections). And I try to use only the minimum thrust needed."Sounds like you are trying to do to much in a short space of time, in something like the 767 I would be at Flap 15, Gear down, and 160 KIAS, BEFORE I even start to descend on the GS (or relevent glide path as shown on the chart), so when I am in decsent all that will need to be done is set landing flaps and the VREF which wont need much of a change in either airspeed or trim."That all, and I try to aim the two thick bars. I can't imagine someone can do this by only looking at the runway: sooner or later you need to add lots of thrust 'cause the flaps eat your speed, or you need to resist the urge to dive for the runway 'cause you're too high. But to make all that in a fluent manner seems very difficult to me."Flaps dont neccesarily eat speed, they just increase the lift so you can fly at a slower speed, make sure that when you are extending to the next set of flaps that your speed isnt to high or too low otherwise you will get big changes in speed/pitch.Maybe try handflying an ILS approach, that way you will have a visual aid to help you even though you are actually flying it visually.Dan.

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<>Actually, you can shoot a very accurate descent profile by doing nothing more than looking at the runway. Here's how.Select an exact spot in the touchdown zone and focus on it. If it appears to move UP on the windscreen, you are decending BELOW the glidepath.If the spot moves DOWN on the widnscreen, you are tracking ABOVE the glidepath.If the spot remains in the center of the windscreen you are ON the glidepath.Think of your "spot" as though is was the glideslope needle on your HSI.To create a "virtual localizer" to go with your "virtual glideslope" just keep the extended centerline of the runway pointing between your legs.That's how I was taught to do it ITRW and at night, at small fields that don't have VASI/PAPI, it can save your bacon.Obviously, this only works in VFRRegards,Jim

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Most a/c in FS isn't really that good. Take your ILS example with Jets. In RL the Jet would approach behind the drag curve with all the draggy bits dangling out (flaps 'n' gear). At the back of the drag curve the speed in unstable, that means that it will tend to drop if not managed, with all the draggy bits dangling out, in RL, you can actually maintain a reasonably high engine RPM so spool times are actually quite quick. FS is a little tardy in this respect.As ragrds the VASIs, if you have four whites then descend more quickly, but you must check the descent as soon as one red appears or else you will probably overshoot. It is easier when low for obvious reasons.Regarding getting into a bank without realising, this is where the instrument scan technique comes in, and it takes some getting used to. On approach you should look at the AI (attitude indicator) then the localiser then the glideslope in turn and repeat four times. Lets call this sequence the primary scan. The the sequence can be something like primary scan, ASI, primary scan, ALT (validate the glideslope is working), primary scan, VSI, primary scan, turncoordinator (to validate the AI is working correctly), primary scan, DME. Just repeat continuously. As you get lower towards DH then bring the alty into the primary scan. There are various techniques so do a search as see whats what. It is very difficult to do to the extent that it becomes automatic and it is easy to become fixated with a single instrument (bad news!!). If you have to make adjustments do not turn more than 5deg at a go and set the attitude according to the AI. In FS you can use the VSI, in reality there is a little too much lag on the VSI (depending on design) and the alty can be easier to use.

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