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Standard basic avionics fit plus VOR indicator, DME, and dual nav radios.
This
tutorial is written for the Microsoft default King Air, but since the FS2000
flight model for this makes it near enough unflyable, I strongly recommend downloading
Steve Small's superb
.air file, which not only makes the flight model more realistic, but gives
performance within a whisker of the real parameters for this aircraft. If you
are using FS2000 standard, you can fly this approach with any panel that is
fitted with dual VORs and can make it up to FL240.
In the situations, the fuel load has been cut to about 25% for the sake of realism. If you need it, I have done a short crib sheet with power and flap settings for the King Air.
The default FS2000 scenery can be used - but be aware that Microsoft have implemented the wrong course on the localiser used for the missed approach.
Pete Pitman has very generously coded a new bgl file for flightsim.com which
fixes the localiser so that a missed approach procedure can be flown correctly.
To use this: back-up your original 'usncils.bgl' (you'll find it in your ...\FS2000\scenedb\westhem\usnc\scenery
folder) then replace it with the one you can download
here.
You should now be able to fly the go-around correctly,
although don't try it with the BC mode of the autopilot engaged. If you download
and fly this approach please make sure you email
Pete and tell him how much you appreciated his work.
FS98 users who have Abacus' "Dangerous Airports" package might like to use that, as Aspen is included.
aspen_situations.zip - extract these files into your \FS2000\pilots folder
This is a non-precision VOR DME approach. The tutorial assumes that you understand the basics of VOR navigation.
Aspen isn't the most difficult approach in the US, but it certainly is one the most notorious. You will understand why if you study the plate - the airport is surrounded by high ground and the IAF offers a bare 2000 feet of clearance, so this is not the place for forgetting the altimeter setting. Given the limited room for manoeuvre, it is vitally important that you are sure of your position before you commence your descent, and that you fly the procedure exactly as charted. For example, if you overshoot the 164 radial from the Red Table VOR too far either way, the choice is between a controlled flight into terrain on the eastern side, and leaving yourself an extremely tight turn onto the missed approach on the western side. And if by any chance you do get established correctly on finals, then there is the small matter of the steep descent from the FAF and the lack of an ILS - you are going to have to fly the bird in by hand. Why the dual nav radios requirement? Without a second nav radio it would be tough identifying the LINDZ intersection on the missed approach - and this is a place where you need to be sure of your exact position and alititude all of the time.
Please make sure you have Indicated Airspeed (IAS) set. If you have True Airspeed set, the instructions which follow will make no sense at all. Ensure that the EHSI and the RMI are aligned, which is the default situation. Also, ensure that you do not have gyro drift checked under the realism settings, unless you are proficient at making corrections for this. Do not use the GPS on pain of death. The approach plate for this tutorial has kindly been supplied by Jeppesen, and we encourage you to visit their web site - the Simcharts packages are well worth the money.
Situation 1: non-precision VOR DME approach runway 15 select situation AspenKingAirV134
This
situation places you at FL180 in the King Air westbound to the Red Table VOR
(KPT). You are flying in the company plane from KORD to KLAX and apart from
some turbulence everything is going fine when the CEO's wife decides to get
sick, big time. She is not an easy lady to please even on a good day, and just
when it seems that things she is feeling a bit better, she throws up all over
the carpet and passes out. Mentally cursing your luck, you ask for a diversion
to Aspen. You are 44 miles out from the Falcon VOR, on a course of 254 magnetic
that the airway takes to the FUNDS intersection, from where a dog-leg in the
airway means that you will have to alter course to 244 in order to fly in to
KPT. Nav1 is tuned to the Falcon (FQF) VOR on 116.3, which is where V134 begins;
and Nav2 is tuned to the Kremmling VOR (RLG) which you need to identify fixes
along the airway. When a clearance is issued for the VOR DME approach to KASE
runway 15 you are only too glad to accept it. Pull out the approach plate and
study it as if your life and your job depend on it; and whatever you do, don't
forget to look at the missed approach procedure.
In
the top right corner of the plan view of the plate, you can see the DBL VOR
with two thick gray lines radiating away from it - and if you look very carefully,
the words "NoPT Arrival Sector via Airway". What this means is that
aircraft transitioning from airways within the bounds of those thick gray lines
don't have to do a procedure turn. The bad news here is that after it dog-legs
at the FUNDS intersection, V134 brings you in on a course of 244 degrees to
the VOR, which is outside the area bounded gray lines - and this means that
you are going to make the procedure turn, which will add to the time you are
going to have to spend in this unpleasant situation. But where is the procedure
turn teardrop that we know and love so well? There isn't one on this approach,
instead you have to make the turn within the holding pattern at the DBL VOR
- we know this because the holding pattern has a thick black line to show that
it is part of the approach procedure (check out the width of the line showing
the holding pattern at GLENO to see the difference). Looking at the profile,
the turn has to be completed at no less than 14000 feet; leaving you only 2000
feet clearance over the highest ground, despite your altitude. Flying the holding
pattern means that you should aim to turn onto a heading of 344 after crossing
DBL, go outbound for one minute, then turn 180 degrees onto a course of 164
magnetic inbound, which will align you for the approach.
All
you have to do for now is fly along the airway towards FUNDS, making any correction
for wind drift as necessary (take a look at FS2000's map view and you will see
the airway). You will know that you have reached the intersection when the heel
of the green RMI needle points to 131 degrees and the DME reads 67 nm - when
this happens you can alter your heading to 244 and start flying in to the Red
Table VOR. How do I know this? It is on the low altitude enroute charts. The
screenshot above shows what the panel should look like at FUNDS.
At FUNDS you can reset your altitude to 16000 feet, which is the Minimum Enroute Altitude (MEA) - the lowest published altitude between fixes that will give you adequate signal reception and 2000 feet of clearance in this area.
The
boss is breathing over your shoulder and there is an air of general panic in
back, so you keep telling yourself to stay calm - and remind them that you are
pilot in command and that whatever is happening they have to take their seats
while you prepare for a landing! You contact Aspen again and arrange for a paramedic
to be ready at the airport. Tune Nav1 to Red Table's frequency of 113.0 and
twist the OBS to 244, watching the needle to make sure you are aligned on the
airway and making any corrections as necessary.
You now need to identify the HERLS intersection, which is where V134 is crossed by the 189 radial from the RLG VOR. Again, the RMI is the key to finding the intersection - when the end without the point climbs up the dial to 189 degrees you are at HERLS, and you can begin a descent to 14,000 feet - see the screenshot labelled "HERLS" to see what the panel looks like. (if you experience any difficulties with this stage of the flight, please read right to the end of this section and follow the link there).
At
HERLS, the MEA for V134 drops to 14,000, allowing us to descend to the holding
pattern, so reset your altitude and begin your descent. Twist the OBS to the
approach heading of 164 degrees and watch the EHSI until the CDI needle centres
- this will happen very rapidly as shown in panel screenshot 1- showing that
you are over the Red Table VOR. From this angle you can make a direct entry
into the holding pattern, by making a standard rate turn onto 344. As soon as
the turn is completed, start timing and fly outbound on this course for one
minute. The minimum altitude at which you can fly the course reversal is 14000
feet and the maximum legal airspeed in a holding pattern at this flight level
is 230 KIAS, but you are unlikely to exceed it in the King Air. The important
thing is to get around the pattern without running out of speed, and therefore
height, on the turns, so be prepared for some throttle jockeying, as the autopilot
isn't that great at maintaining altitude in turns. It may take you a few tries
to get it right, and my advice is to to enter the pattern high, if anything,
and to conserve as much altitude as you can, so you can enter the inbound leg
of the pattern with a few hundred feet over the minimums to give you some comfort.
Panel screenshot 2 shows the situation inbound to DBL, just about to begin the
descent.
Once
you cross the VOR, reduce to flight idle again, drop some flap, reset the altitude
to 12700 and begin a descent at about 1500 feet per minute. Watch the DME like
your life depends on it, which in the real world, it would. At 3.0 DME, reset
the altitude to 12200 and get ready to intercept the FAF, which is at ALLIX,
6.0 nm from KPT. Screenshot 3 shows the situation as the aircraft reaches ALLIX.
The visibility is nil, but you are cleared to make a descent to the MAP, which is at D11.0 from DBL, at an altitude of 10200. There is an intermediate step descent before this, which is reached at DME 9.5, when you can descend to 10400 feet, so rest the altimeter to this setting, and once you are past DME 9.5, reduce it to 10,200 and start looking for the runway. This might be a good time to drop the gear, and depending on how slow you plan to go, full flap might not be a bad idea.
Somewhere
in between ALLIX and the MAP, you should break out of the cloud and go visual.
Your natural tendency will be to give a wild scream of joy, yell, "Tally
ho, we're going in chaps!" cut the throttles and dive for the pavement,
but as your check ride instructor, I urge a bit of caution here. When you see
the airport, you will be four to five miles from the runway and nearly 2500
feet above it. In the time it will take to cover the distance, you will require
a descent rate of approaching 1700 feet per minute right to the threshold, and
while this isn't a particularly steep rate of descent in the normal scheme of
things, it is if you are trying to land a plane at the end of it. So check out
the circle-to-land minima. The King Air is a category B plane, so you need to
stay within 2 miles of the ends of the runway while you do your circuit - there
is very little more space than this available anyway.
Now I have an apology to make. Will anyone who had trouble with this approach please click here. And, by the way, if you try to read this before you execute the descent, you should be ashamed of yourself.
Situation 2 - a missed approach. Select situation file AspenKingairJ206
OK,
what would a trip to Aspen be without a missed approach? I guess some of you
suffered enough on the last one, so there aren't any surprises here, just a
bit of testing of your reflexes. I got bored with the Lear, so I decided to
fly this in the Abacus Rockwell Twin Commander, but the situation file will
load the King Air for you. If you have Corporate Pilot, give the TC a go.
This time you are approaching on J206, which is within the no procedure turn (NoPT) arc, so you won't have to do a turn in the holding pattern - you can just fly straight in after you cross KPT. The aircraft is set on a heading of 131 magnetic and at about 30 miles out, you can throttle back and begin your descent to the DBL VOR, with the altitude set to 14000 feet - note that the MSA for this quadrant is 12500 feet, so you have plenty of clearance. Remember to make allowances for any wind drift - deflection of the CDI should alert you to this. And, er... do remember to set the altimeter to the correct altitude by tuning in to Aspen ATIS on 120.40 and pressing "B" before you start the descent to the VOR.
Remember
that you will cross the KPT at FL140, so the DME will not zero - and you will
know you have crossed the VOR when the DME starts to increase again. The lowest
it will go is about 0.4 nm, though in practice you will want to begin your turn
slightly before you reach the VOR in order to avoid overshooting your outbound
track.
It is a good idea to prepare for your crossing of the VOR by twisting the OBS to 164. Once you are ready to make you turn, alter your heading to 164 as well, plus or minus any allowance for wind, then chop the throttles to flight idle and configure the aircraft for approach. If you are using the Twin Commander, this is the moment to thank Terry Hill for the realistically stable .air file of his plane. You might also email Abacus technical and ask them to fix the problem of the missing "hundreds" digit in the altitude selector (-:
Once
you are established on your descent from the VOR, you can follow the instructions
for the flight above, making the stepped descent all the way to the MAP - but
this time, when you reach the MAP at D11.0 from KPT and an altitude of 10200
feet, you will still be IFR and you will need to declare a missed approach.
This is the situation shown in panel screenshot 1 of this section.
Advance the throttles, pick up the gear, and as soon as you have enough flying speed to do so, start to raise the flaps. At the same time begin a turn to starboard, beginning a climb as soon as you possibly can.
At this point, some discussion of localisers might be useful. Effectively, a localiser works like a VOR that only broadcasts a signal on one radial. The majority of localisers are used as part of an ILS and they have a second signal which broadcasts a glide slope along that same radial, and an aircraft which approaches the localiser from the "front" side - flying TO the airport, simply has to tune the localiser, twist the OBS to the radial it broadcasts on, and adjust heading until the CDI needle centers. If the CDI deflects to the right, you turn right, if the needle goes left, you go left. It pays to make small corrections, because the nearer you get to the threshold, the narrower the beam and the more sensitive the CDI until it won't center at all.
Localisers
sometimes haves a "back course," which is a signal on the same frequency,
but orientated at180 degrees to the front, or approach course. If you fly down
the front course of such a localiser and continue on right over the runway without
landing, you can then fly away from the airfield on the back course, in the
same way that you can fly across a VOR using a radial you tuned as you approached
it. Effectively the back course is simply a backward extension of the front
course radial and it is suppressed on many localisers. The one time back courses
cause confusion is the admittedly rare occasions when you have to fly an approach
towards an airport using the back course localiser, in which case the
CDI will reverse sense (i.e. the needle goes left when you need to turn right
and vice versa), unless you cheat and twist the OBS to the front course heading.
Incidentally, if a back course localiser is used as part of an ILS, the one
thing you can be certain of is that it won't have a glideslope. But the main
purpose of this long digression is to alert you to the specific use of the back
course localiser in Aspen - it allows you to tune the localiser radial and fly
out on it using a normally sensing CDI (it goes right, you go right).
Now
we have a problem, because as I indicated in the introduction, in FS2000 the
localiser which is used to fly the missed approach at Aspen has been implemented
as standard localiser with a front course of 120 degrees. This makes
it impossible to fly the missed approach realistically with the default FS2000
setup, although if you have installed Pete Pitman's update you will have no
problems flying the procedure as charted.
In a real aircraft you would have the localiser tuned as the backup frequency on Nav1 as you began your descent, and would just punch the key to swap it in, but this is very rarely implemented on FS2000 panels and neither the King Air nor the Twin Commander panel allows you to do this. Given that it is very unlikely that you have anyone in the right hand seat either, I think it is legit to hit the pause button for a second and retune Nav1 to 108.5, Nav2 to 113.0, twist the OBS to the outbound course on the localiser and switch the DME to read from Nav2.
Remember that if you are flying with the default FS2000 scenery you will need to twist the OBS to 120 degrees - not 300 degrees - as otherwise the CDI needle on the EHSI will "reverse sense", owing to Microsoft's mistake in setting up the localiser. If you get reverse sensing, a deflection of the CDI to the right means you have to turn to the left, and flying out becomes somewhat counterintuitive. From now on, I will assume you have installed Pete's upgrade file.
Until
now, you may have been wondering why the localiser is used for the missed approach
rather than an ILS, but in these weather conditions, I am sure you will appreciate
the reason. With rising ground on all sides, there isn't any margin for errors,
and the localiser allows you to fly out in the complete certainty that you aren't
going to hit anything solid. The one thing you have to be slightly careful of
is that you intercept the localiser at a reasonably gentle angle - whatever
you do, don't intercept it at 90 degrees, or you could fly straight through
it into a mountainside before you can turn to pick it up again. So that turn
after the MAP needs to be reasonably steep in order to give you room to roll
out onto 270 and intercept the localiser at a sensible angle. Once the CDI centers,
raise any flap you have left, set your altitude to 14000 feet, switch on the
FD and the autopilot and climb out at your best angle. Panel screenshot 2 shows
the situation as the aircraft begins interception of the localiser, with the
CDI deflected left and swinging to the center - note that in the general excitement
I haven't got quite the right course tuned on the OBS.
This
is the moment where the requirement for dual nav radios becomes apparent and
the instrument gladiators among you can have their moment of glory. The missed
approach procedure at Aspen has you climbing out on the localiser until you
intercept the 244 radial from the DBL VOR at the LINDZ intersection, which is
at 12.6 DME from the Red Table VOR, hence the reason for swapping the DME to
Nav2. While it is technically possible to approximately identify the intersection
with a single nav radio, it isn't legal to fly this approach with such limited
equipment.
In the Twin Commander, you have dual VOR displays and with the Nav2 radio tuned to 113.0, and Nav1 to 108.5, all you need to do is to watch the VOR2 indicator. When the "heel" of the VOR2 needle (i.e. the end which isn't the one with the arrow on it) points to 244, you are crossing the 244 radial from the DBL VOR (as in panel screenshot 3) and can turn left onto a heading of 244 degrees. In practice you will want to begin the turn slightly early, or you will overshoot the radial.
At this point you can tune your Nav1 radio back onto the DBL frequency of 113.0 and fly on a heading of 244 (once you have the CDI centred) until the DME reads 22.7 nm and you have reached the GLENO intersection, where you can enter the holding pattern. No sweat.
Situation 3 - a normal approach. Select situation AspenKingairV421
This
situation places you on V421 inbound to the Red Table VOR at 17500 feet and
about 16 nm from the VOR. The weather is as it was at Aspen on 1st June 2001,
with clear skies and VFR conditions. I threw this approach in because the weather
on the last two situations was so bad there was no chance to enjoy the scenery.
On this approach you should be visual at the VOR, and you are therefore free
to make a descent as soon as you wish. My advice is to reduce speed to 140 IAS
as soon as you can, and go for a straight-in approach. This will mean lowering
the gear and dropping full flap almost as you cross the VOR, to cut your airspeed
to the minimum and increase your descent rate to the maximum - if you don't
do this, you will have to do a circuit in order to get down. As you will remember
from situation 1, there isn't a great deal of room to do that.
Happy landings.
Andrew HerdRead the tutorial on basic instrument approaches.
Read an appraisal and response to the tutorial from Bob Yarmey, President of Professional Aviation Servies.
