Questions About ILS/VOR Approaches

I have been learning FSX for over four months now. I have spent a good 2 to 4 hours a day, sometimes more, learning navigation, landing techniques, and such. Of all the things that cause the most trouble is the ILS approach. It is so inconstant. I will do the same thing over and over but it will act different more times than not. The autopilot will catch the ILS signal 50% of the time. Sometimes it will also meet the runway at a say 5% angle. A lot of times it will also not catch the glide slope but will catch the runway. If it does one shouldn't it do the other too? The purpose of the ILS is to be able to fly blind until the last minute upon seeing the threshold of the runway. If things aren't performing properly, like as I have described above, then it's too late to correct and you're dead. I would love to master this ILS thing before moving on to other functions but I just can't get past these ILS inconsistencies. Anyone out there have any insight into this? Is it a programming error? Is it a computer glitch or software glitch? Love to get someone else's input on this.

Thanks. DR

The ILS approach is a precision approach and does an excellent job of guiding the aircraft to the runway, assuming it is interpreted & flown correctly. Your comments beg several questions that should be addressed before any further advice is given. That is, are you using and are you familiar with the ILS approach plate for the airport you wish to land at?

The establishment of a stable approach airspeed and altitude dictates how well you will execute that approach. All ILS approaches use the same basic criterion and it all depends on how well you know your airplane and associated power settings, airspeed control, descent rates etc. There is a tremendous amount of information on the approach plate and it must be studied, PRIOR to making the approach. Keep in mind I have not mentioned the other important issues such as the enroute phase of flight that gets you to the approach.

Also keep in mind when flying instruments, learning to scan the instruments properly is also of great importance among a host of other things to master. In any case welcome to the Wonderful World of Flying!

Ron R.

ATP-Multi-engine

CFI-A

CFI-I

CFI Multi-engine

Basic & Advanced ground instructor

Type rated Cessna Citation 500 series

I think 50% in 4 months is a very good score! Keep practicing.

Also, I often go around from 200-100 ft. Hoping the aircraft in front hurries a bit getting off the runway. The "go around" call from the tower comes at that time too, no sooner. Practice your go-arounds. Landing is one thing. But staying alive is what counts.

The old saying: "a go around is not a sign of poor flying, but of good judgement" still goes.

Have your flaps set well before you get to the glideslope. Fly a "stabilised approach". -> no flap changes, no large speed changes, and no large autopilot changes on final. If any of those ARE required --> Go Around.

What plane are you trying this in and where?

Let's get something out of the way first: you start out learning the ILS by flying it by hand, not on autopilot. So you get a feeling what the AP must do, and you learn what the ILS actually is for...

The ILS system existed long before airplanes had autopilots that could follow it automatically. As opposed to a visual landing, the ILS provides you with the information you need to hit the runway threshold - even in zero visibility. It is showing these on your primary flight instruments (as needles, flags, pionters, whatever), hence the name Instrument Landing System. You will always get your vertical position relative to the glideslope (above/below) and your horizontal position relative to the ILS "beam" (the same as a VOR really, and the same instrument most of the time).

For the autopilot and ILS : how good that one works depends on the airplane. Addon planes sometimes override the default AP logic. But every autopilot has limits as to when it can actually catch the ILS beams (max 30 degrees offset from the beam, correct altitude and attitude, correct speed, correct management of the descent). You can confuse your AP when it is already established by pulling power off too fast, by dropping flaps too fast, by deploying spoilers, turbulence or too much wind, etc. The AP cannot cope with everything you might do to the airplane yourself.

Or you happen upon an accurate, but offset Localizer, like in Innsbruck. Those are set at an angle to the runway, as the direct approach is not possible (mountains...).

How I do it in the stock a321, I make sure my flight plan is made so that the last 20 miles of approach are almost straight, I don;'t actually turn to runway heading til around 11miles out though, by the time you are 15 miles out you should have stable and level flight of around 2500feet AGL (runway elevation) and be established with flaps and landing speed. Make sure your heading and course are set to runway magnitude, also make sure that your nav1 and nav2 radios are set to the ILS frequency for the runway you are landing on.

As you turn to line up with the runway or are a few degrees from it, siwtch gps to nav mode and make sure the nav1/loc switch is still selected. Also press the ILS switch this brings up ILS markers on your PFD. Watch closely the glidescope marker as it nears your current altitude this is the time to press the apr or app button ( usually around 8.5 - 9NM from landing). Now watch your height and know the runway elevation at just under 1000feet, turn off your speed hold and autothrottles, at around 50feet AGL hit f1 to idle the throttles and at 30 feet AGL go to flare. This should get you down every time.

How I do it in the stock a321, I make sure my flight plan is made so that the last 20 miles of approach are almost straight, I don;'t actually turn to runway heading til around 11miles out though, by the time you are 15 miles out you should have stable and level flight of around 2500feet AGL (runway elevation) and be established with flaps and landing speed. Make sure your heading and course are set to runway magnitude, also make sure that your nav1 and nav2 radios are set to the ILS frequency for the runway you are landing on.

As you turn to line up with the runway or are a few degrees from it, siwtch gps to nav mode and make sure the nav1/loc switch is still selected. Also press the ILS switch this brings up ILS markers on your PFD. Watch closely the glidescope marker as it nears your current altitude this is the time to press the apr or app button ( usually around 8.5 - 9NM from landing). Now watch your height and know the runway elevation at just under 1000feet, turn off your speed hold and autothrottles, at around 50feet AGL hit f1 to idle the throttles and at 30 feet AGL go to flare. This should get you down every time.

The approach plates for the airport/runway will tell you exactly how you have to fly the ILS: course, altitudes, waypoints, speeds, glidepath angle, decision height - everything you need to know.

8-9 miles is to late. You are almost at the glideslope then.

Try pressing app mode 20-15 nm out. That gives the autopilot more time to line up. With the runway. (It will maintain altitude for you untill you reach the glideslope.)

make your altitude 2500-3000 above ground level (AGL) well before that time. With flaps set (full or almost full). And speed set correctly for those flaps.

Oh, and practice in the boeing 737 or 747 or the cessna172 or Beech Baron. The a321 is pretty much the worst to learn on.

If you use th search box (top of this page) and search for:

fix buttons autopilot 747 il88pp

you will find my fix for the 747 virtual cockpit.

(you probably noticed some buttons in the 747 VC don't work.)

My ILS with 800's -

Put on VOR lock as soon as you hear the "beeps" from the nav beacon

Dial down the bank angle to 10 or 15 degrees (bank dial is the outside edge of the heading dial for the autopilot)

Slow down to 200 KTS and deploy approach flaps

Once you are lined up on the ILS markers hit the APP hold right away, dont hesitate.

Set speed to 160 KTS and deploy landing gear and another two notches of flaps

Wait till sub 1000 feet, and disable APP hold and manually land at full flaps while coasting to a perfect landing.

Profit.

How to land in an Airbus A320 using a standard 3 degree ILS. I hope this helps. Forgive typos, I'm writing this on an iPad.

Activate the approach phase when you intend to take out flap 1. It can be done sooner, but it is unwise to do it too early as this locks in the gross weight to the FMGC, so will give an incorrect VApp.

Fly selected 220kts when nearing the base leg, before you're ready to take flaps one. This has two advantages. The first is that you can take flap 1 at any time, as you're below VFE for that stage of flap. Secondly, in the 319 you can hold 220kts and still use full speedbrake. In the 320, VLS will rise to about 225kts when you use speedbrake so you won't be able to use speedbrake with a clean 320 at 220kts. That's something to consider. If in a 320, close to coming onto base leg and wishing to use speed brake, either increase to 230kts or take flap 1 first.

Make sure the LS pushbutton is on. It will show a green light and the vertical and lateral deviation scales will appear on the PFD.

Take flap 1 about 15nm out, or when advise by ATC to slow below Green Dot speed. When you do this, PUSH the speed knob on the FCU in so that speed becomes Managed by the computer. When cleared for the approach by ATC, there are three possibilities:

1. You are more than 25nm from the runway. In this case, you must wait until you are within 25 miles of the runway and then move onto possibility 2 below:

2. You are within 25nm but more than 17nm from the runway. Press the LOC button. When you are within 17nm, move onto possibility 3 below:

3. The most common possibility - you have been cleared for the approach and you are within 17nm of the runway. Press the APP button and immediately after that, turn on the other autopilot. THERE IS NO NEED TO PRESS LOC FIRST. I see so many people on twitch waiting until they are on the localiser before pressing the APP button. The Airbus will NOT descend on the glideslope until the localiser has been captured, so as soon as you have been cleared and are within 17 miles just press the APP button.

Assuming you are below the glideslope when this happens, you will capture the localiser before capturing the glideslope. In the airlines we carry out CDAs, Continuous Descent Approaches, and part of the fun of these is trying to get G/S* and LOC* on the PFD FMAs at exactly the same time. I wouldn't recommend that beginners try that. When you capture the localiser one of two possibilities will exist:

1. You have been asked to slow to below S speed, e.g. ATC may tell you to slow to160kts. In this case, select flap 2 and THEN select 160kts. Do NOT select anything below S speed until you have actually gotten out the second stage of flap. Depending on your speed, the rest of the configuration should take place at...

For 180kts, 7nm from the threshold

170kts, 6nm

160kts, 5nm.

Configure by first pushing to Manage the speed again, then immediately selecting Gear Down. Once the gear is down, select Flap 3 then Flap Full (assuming you're doing a flap full landing - more on flap 3 in option 2 below). This should have you decelerating at 150kts at 4nm.

2. You have free reign over your speed. In this case, you must judge what is appropriate factoring in the tailwind and descent gradient. Assuming a nominal headwind, select Flap 2 when you are 8nm from the runway, or 2000ft above the runway elevation. When the flaps are out, select gear down, then when the gear is down and locks, flaps 3 and then flaps full. If carrying out a Flap 3 landing (remember to turn on the GPWS FLAP 3 mode on the overhead panel, as well as selecting Flap 3 in the MCDU PERFECT page), obviously don't take out flap full.

Once your landing flaps are out, you should be fully configured before 1000ft AGL (above ground level). Complete the landing checklist. When visual, and only when visual, disconnect the autopilot and begin hand flying. If carrying out a CAT3 autoland, follow the autoland procedures instead. You should pass overhead the runway threshold (piano keys) at 50ft, as audibly indicated by the radalt. At this point you should have maintained a stead 700ft/min down the glideslope. Continue this until the flare. At the same time, 50ft, look to the end of the runway. This will avoid "ground rush", which causes lots of novice pilots to get uncomfortable at the way the ground appears to be getting closer and closer, causing them to flare too early. Look to the far end of the runway throughout this final stage. Listen to the cadence of the radalt call outs. If it starts getting too quick. You may need to flare sooner. If it is too slow, you may need to hold off on the flare. This would generally be caused by you not flying an accurate 700ft per minute as you pass 50ft (at 50ft ground mode locks your current pitch attitude in and bases its pitch-down momentum on this - if you weren't at the correct pitch, the correct rate of descent, it will be incorrect). In a 319, flare as the radalt calls 20ft. In a 320, flare when the radalt is between 20 and 30ft (aim for a few seconds after the '30' call out - you're looking for a flare at 25ft.

Keep flying the aircraft. Just because you're in the flare doesn't mean you can close your eyes and forget that you are flying a plane. Maintain the centreline using wing-down while straightening up and crab with rudder. Pitch up or down to adjust any over- or under- flare. Close the thrust leavers as you flare. Close them promptly but you don't need to slam them back.

This should hopefully help a few of you. I have been a pilot on the A320 for the last 5 years and we do this 95% of the time. It works.

Good luck!

I am flying mostly the 737-800 around the Northwest. PDX...SEATAC...Sometimes SAN FRAN.

http://flightaware.com/resources/airport/KSEA/IAP/ILS+OR+LOC+RWY+34R

http://flightaware.com/resources/airport/KSFO/IAP/ILS+OR+LOC+RWY+28R