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B777 Raw data ILS technique

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B777 Raw data ILS technique

Old 17th Jun 2012, 09:56
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B777 Raw data ILS technique

Any tips on how to fly a raw data ILS approach on the B ???
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Old 17th Jun 2012, 10:18
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Ummm lemme guess.. Keep the two needles centered ??
(sorry man cudnt resist)
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Old 17th Jun 2012, 10:27
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Utilise the Map display- If the track line is on extended center-line, you're tracking the LOC. If you need to correct in azimuth, make sure the track-line crosses the extended center-line before the threshold..If it does, you're on an intercept track.

For G/S, the FPV helps. Fly so the "tail" of the FPV is on the horizon, and you are on a 3deg descent. Attitude between zero (maybe -.5) deg and 2 deg gives a good range of RODs.

Last edited by Wizofoz; 17th Jun 2012 at 10:28.
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Old 17th Jun 2012, 12:06
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Wiz - that is not raw data. GE90 has it right.
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Old 17th Jun 2012, 12:38
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Ge90 beat me to it

On a more serious note it actually is just as simple as that.
On the airbus to help you with crosswinds, additionally once the needles are centered, select track of the inbound course and fly that.
With the localizer centered, flying the inbound track, you will never go wrong.
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Old 17th Jun 2012, 13:20
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The industry is often concerned about pilots reverting to old habit or previously trained practices to the detriment of flying modern technology-augmented aircraft. Yet when faced with a basic task raw data ILS, there is an apparent lack of understanding of the basics.
So what is being taught as basic; do new pilots ever fly raw data ILS, or only use FDs etc in training aircraft?
If taught, then what is taught; the basic old-style raw data ILS or something new, anticipating (assuming) that operations will always be technology aided?
If the old style is taught, why should pilots forget the basics (understanding) or the means of recall and application? The basics are usually required in situations involving system failure.
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Old 17th Jun 2012, 13:47
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Basic ILS technique.

even before starting the ILS, know the following:

initial rate of descent is approximately 5 times your groundspeed in knots...Apch groundspeed 140 knots...your initial descent rate 700 fpm...make your calculation in advance. 600 to 700 fpm for most jets to start.

consider the winds aloft , its effect on heading required to make good the localizer and how they will change as you get closer to the ground. within 300 feet of the ground the winds change (also at base of clouds if defined based exists)...they swing to closer to what the tower reports.

step one:select course, tune and identify the ILS freq, make sure beacon receivers are on HIGH

Intercept localizer and make a good guess as to the heading required to maintain. split your scan between the needles and the basic flight instruments...don't chase the needles, try for the heading making refinements as you go

as the glideslope needle comes alive, configure the aircraft for landing so that by the time you are ON GLIDESLOPE, you are fully configured for landing and stable in your 600-700fpm descent...TRIM and set the power.

now, monitor your heading and descent (airspeed too) as your marker beacon starts to sound, select norm or llow.

when the marker beacon sounds again, OM, start your time in case you lose the glideslope, you could ocontinue with the localizer only apch....you do not need to TIME to the missed apch point if ONLY considering the ILS as DH is your missed apch point.

monitor and fly the apch, making small refinements if a calm day...on a rough day you will have to be MORE on top of things...as you apch DH adjust your heading to compensate for reported winds on the ground...also your rate of descent may slightly be reduced to maintain glideslope. AT DH, have your copilot tell you if he can see the 11 required items to continue, if he has them in sight, look up, adjust and scan between outside and inside as you acclimate to looking out the window...have copilot call speed and rate of descent to touchdown.



send me 20 US dollars for helping you out

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Old 17th Jun 2012, 14:03
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I am getting quite worried when an airline pilot flying or transitioning on a widebody needs to ask how to fly an ILS without the gimmicks...this is basic stuff and should be done almost on a daily basis...even a single engine raw data ils should be practiced in the sim, without the rudder compensator obviously...
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Old 17th Jun 2012, 14:21
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Sorry guys, but standard definition of Raw Data on EFIS aircraft in my experience= no flight director.

Been that way in the last four airlines I've flown for, and how it is taught at my current one- usually by me!!

I'd be very interested in how many outfits do as described above. Not saying one is better than the other (in fact I think having to fly without a MAP display would be great pracice), just not what I've experienced.

Last edited by Wizofoz; 17th Jun 2012 at 14:25.
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Old 17th Jun 2012, 14:32
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Help! I'm hoping this is some spotty teenager asking for help flying his FltSim. If not it turns out my irrational fear of flying as self loading freight isn't as irrational as I'd thought. And that's coming from someone who straps a Martin Baker to his arse everyday and does 550kts IAS.

Last edited by High_Expect; 17th Jun 2012 at 14:33.
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Old 17th Jun 2012, 14:48
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@Wiz, yes, our definition is flying by raw data sources (basic ILS) and without flight director of course. However some like to keep the map display going on the ND and use the needles on the PFD as raw data source, FPV is seen as a cheap ersatz FD by some as our simulators cannot fail it. Personally i like to switch the ND into APProach mode and use the basic needles there and no FPV either.

My company doesn't have a fixed opinion, its up to the pilot flying how he wants to configure his displays, however it is recommended that at least one pilot has a map display with vertical situation display active during approach to help with overall situational awareness. In the raw data case that would usually be the PM.

Apart from that, it is basic instrument flying and one should keep those skills up for that bad hair day when the rest isn't available and some other problems might demand some brainpower as well, better not to be overwhelmed by raw data flying alone.
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Old 17th Jun 2012, 15:02
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Genlemen. RTFQ!

Get out a picture of your PFD and follow me here. Everything you need is there. You need a pitch target and a heading target.

For a 30 Flap landing your pitch target is about 2 deg. Place the small square on the a/c symbol just under the 2 1/2 line on your ADI. Make adjustments as required but always come back there. For a 20 Flap approach your pitch target is 2 1/2 deg.

Now look at the bottom of your PFD. The half compas display there has a white track line. This is your track over the ground. On your PFD, set runway heading. (It's not going to slew there automatically unless one of you has your FD on and arms the Approach, but we're talking raw data here.) Now as you steer, your heading target is your heading bug. Steer to lay the white track line over the heading bug. Once you're squared up your corrections should be very small. Keep the track line within or very close to the heading bug.

Voila. Send only happy thoughts.
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Old 17th Jun 2012, 16:47
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Get established on speed, on GS, on LOC. 2 degree nose attitude. Start with 54% N1 (horrors, no A/T's too?).

Make small changes. Scan, scan, scan. The quicker you notice the deviation trend the smaller the correction.

It's almost always trending away. The trick is to notice it ASAP and make the smallest correction necessary so that you don't start a trend in the opposite direction! The rate of deviation might be very small but eventually you'll notice one or two, make the corrections, and scan, scan, scan.

MAP display helps. If the track line is parallel to the runway the ILS displacement will increase as you get closer even though the physical displacement from the runway centerline is not increasing. Use the MAP display, along with your heading, to avoid making large heading changes, especially as you near the runway and the sensitivity increases which requires smaller and smaller corrections.

Raw data flying, along with s/e approaches, especially raw data s/e approaches, along with strong crosswind landings, is what culls the herd.
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Old 17th Jun 2012, 16:59
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It really is very very scary when you start hearing questions like this from widebody pilots.Basically learning on the job with 300 people behind them. It's not the individuals fault though, it's the airline management that puts them there.
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Old 17th Jun 2012, 17:30
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sevenstrokeroll said:
"AT DH, have your copilot tell you if he can see the 11 required items to continue,"

Please pardon my ignorance, what 11 items are you referring to, I actually have never heard of this before. Not trying to start a bun fight just curious.
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Old 17th Jun 2012, 18:47
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Any tips on how to fly a raw data ILS approach on the B ???
If ILS is too difficult maybe first work on the raw data NDB approaches...

Lately wondered what the meaning of the first P was in PPRuNe.
I'll take the train from now on.

Last edited by have another coffee; 17th Jun 2012 at 18:50.
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Old 17th Jun 2012, 19:25
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All of the above info is good for tracking the LOC.

Nobody has mentioned using the Flight Path Angle. Set -3 degrees on the FPA and life is easy. Fly the wing of the FPV into the horizontal bars and maintain them there. Of course you have to be on the glide slope in the first place.

I am assuming this raw data ILS is for a skills test in the sim and the PNF flight director is ON or the FPA won't be available.

Glass guys lose their scan over the years so maintaining the scan of G/S, LOC, Track and attitude is good practise for the raw data. A/T will be looking after the speed.
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Old 17th Jun 2012, 19:42
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A/T will be looking after the speed.

Please someone confirm these comments are not actually from professional pilots on flying raw data.
Just learned I better take the bus.
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Old 17th Jun 2012, 20:29
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hi busserday

no problem...many years ago all we said was, you need to have the runway environment in sight to leave DH and land.

runway environment could mean many things and then someone wrote down what the runway environment really meant. it is in the US FAR's in a couple of places...I think part 91 is the place to start.

at DH if you see the flashing strobe lights of the approaching lighting system but see nothing else, you may continue descent to touchdown zone plus 100' until you see more of the items:

runway threshold
runway markings
threshold lights
runway edge lights
red terminating bars
centerline lights
REIL lights
touchdown zone lights
touchdown zone markings

now in practical flying, you don't think, you just say: can I see to land?...OK land. trying to remember that stuff at DH is a handful...
indeed< I haven't looked it up and am doing it from memory...so please anyone with the regs in front of them can correct me.

and there are professional pilots to day who don't know they can go to touchdown zone elevation plus 100 feet just on the strobes/rabbit(as we called it).

I grew up flying in really heavy fog and the above trick (perfectly legal) is what seperates the landings from the go arounds.

Last edited by sevenstrokeroll; 17th Jun 2012 at 20:31.
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Old 17th Jun 2012, 20:45
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Thanks SSR,
although discussed at length, haven't seen this criteria before. Good gin.91.175


Last edited by Busserday; 17th Jun 2012 at 21:14.
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