Transitioning to Visual
I found the following old article...might be fun to discuss or pass on to new pilots:
http://www.avweb.com/news/airman/184.../184509-1.html |
Link doesn't work for me - just says webpage cannot be found :(
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Transitioning to Visual Email this article |Print this article
The weather is right at minimums, and you've flown a perfect ILS with the needles right in the doughnut all the way to decision height. But you're not done yet! The toughest part remains ahead: transitioning smoothly from instrument to visual references at DH so you can land. Here are some ideas about how best to do this in both one- and two-pilot situations. June 3, 1996 byJonathan Regas About the Author ... Jonathan Regas flies DC9's for a major U.S. carrier. He has 10,000 hours in over 60 aircraft types from Cherokees to MU-2s to Metroliners and Jetstreams to Sabreliners, including 4,500 hours in DC9's. Jon lives near Washington, D.C. One of the most difficult times in a pilot's workday is the transition from purely instrument cues to visual cues needed to land from an ILS approach. In my flying career, I have had the misfortune to see such ham-fisted maneuvers at this critical point that I thought I would share some ideas on the subject. Transitioning to visual from an ILS is one of those times that it's really advantageous to have two pilots in the cockpit. So let's start off assuming we have a two-pilot crew; we'll talk about single-pilot operations a bit later. The non-flying pilot A key concept here is that both pilots‹the "flying pilot" and the "non-flying pilot"‹we'll call them FP and NFP‹have significant roles to play. So whether the NFP is a formal crewmember or a pilot-buddy of yours who's just along for the ride, a formal briefing of the NFP is in order, and should be done well before commencing the approach. Among the briefing items must be FAR 91.175(c)(3) that allows us to continue descent below DH to a height of 100' above touchdown zone elevation predicated on seeing only the approach lights. It is legal, and properly done, a safety-enhancing method of approaching the runway. To continue below 100' above TDZE, you must have the red terminating or side row bars in sight, or else you must see the runway, runway lights, runway threshold, threshold markings, threshold lights, touchdown zone, touchdown zone markings, touchdown zone lights, runway end identifier strobes, or VASI. Keep it stabilized A good stablized approach is vital to a good landing when the visibility is right at minimums. Many regional airlines instruct their pilots to approach with one flap setting, and once "visual" with the runway, to drop the flaps down to the landing position. What a waste of a good stable approach! While there may be some concern about aircraft performance on a one-engine go-around, I believe you should avoid such last-minute flap management procedures that destabilize the approach right at the most critical moment. Now assuming you are on-course and on-glideslope as we approach decision height, the FP should stay on the instruments until specifically told to look up by the NFP. Why? Because if the FP looks up at DH to look for the lights or runway, a subtle deviation from glidepath will result. Those seconds spent looking and deciding at DH will almost certainly make for a poor approach. So let the NFP tell the FP to continue the descent below DH (on the gauges) based on seeing the approach lights and sequenced flashers. The FARs say you can legally do this, and it will help maintain the trajectory of the aircraft that the FP has been refining since the outer marker. When there is something worth looking at, the NFP can tell the FP to "look up" along with a slight correction like "2 degrees right". Start to learn how the winds shift at your favorite airports just around the base of a defined cloud layer or about 300' above the airport due to surface friction. Be ready for an appropriate correction. Don't look up at DH Don't look up untill the NFP can see either the runway or the approach lighting system cross bars. I'll refer to these approach light cross bars as "the roll bar". Why? Because it is the first visual cue that allows an approximation of a visual horizon. Take a good look the next time you fly and you can begin to see that you can control the plane with reference to these bars (and cross check of flight instruments) as your eyes become accustomed to visual flight. Just trying to fly by looking at the sequenced flashers and stationary approach lights will lead you to the runway but most likely lead you to overcontrol the aircraft until you can establish an outside horizon reference. When you have established a visual reference with the "roll bars" and/or the runway, say "I am visual" to your NFP. At this point, the NFP should transition to instruments and verify the flight path. The NFP should make verbal callouts of deviations from the flight path or reference airspeed: e.g., "one dot high, airspeed decreasing." If your ops manual has standard phraseology, use it. If not...CREATE IT! Now is not the time to misunderstand a single word. Phraseology I won't try to give you a new vocabulary, except for the "roll bar". Make one up that works for you. Here's an example of what works for me: At 1000 feet above touchdown zone elevation: NFP: One thousand above, checklist complete. At 500ft above TDZE: NFP: 500 above, on-course, on-glideslope, Ref plus 5, sinking 700, no flags. If you are off any of these targets, the NFP sould call them out: NFP: One dot high, one dot left of course, Ref minus 5, sink 400. The NFP should also call out if any flight instruments or nav instruments are not in agreement. At 100 above dh: NFP: 100 above, I am going outside. At dh: FP: At minimums. If NFP doesn't have the approach lights in sight at dh: NFP: Nothing in sight, go around. FP: Going around. If NFP does have the approach lights in sight at dh: NFP: Approach lights in sight, continue descent. FP: Continuing descent. NFP: Roll bar in sight, look up. FP: Looking up...roll bar in sight...I am visual. NFP: I am inside. NFP is now looking at flight instruments, calling flight path and airspeed deviations, and ready to assist at any time with a go around! Single-pilot operations For those of you who fly alone, here are a few ideas you can try: €Verbalize the NFP calls for yourself. Or if you have a trainable right-seat passenger, press him or her into service to make altitude calls and look for the approach lights. € If autopilot-equipped (and you should be for single-pilot IFR), and if your flight manual permits, let "George" fly a coupled approach and don't disconnect the autopilot until 100' above TDZE when you have the roll bars or runway in sight. € Stay on the gauges and don't look up until DH. If you see the sequenced flashers, go back to the gauges and continue the descent primarily on instruments to 100' above TDZE. During this phase, try moving your eyes quickly between inside and outside, as if you are including the windshield in your instrument scan. Don't stop scanning the instruments until you're sure you have solid visual reference. Conclusion The whole idea of this article is for both pilots to work together until and after solid visual cues have been established by the flying pilot. The decision part of Decision Height can be aided by the 100'-above-touchdown-zone proviso of the FAR's based on seeing the sequenced flashers of the approach lights. Know what to expect from your crewmate‹or from yourself, if you are alone in the cockpit. If you have been "on the beam" all the way through to DH, remember not to overcontrol or destabilize the approach at the last minute. |
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Thanks for the transcript sevenstrokeroll (and the working link, error 401)
Interesting to see that you are US based and also that the article appears to be about 18 years old. Does it represent the industry "best practice" in the USA today?? I ask because the last 3 UK based employers I have worked for have all had the standard SOP of changing handling pilot at minimums. This seems to work really well for me - either as handling pilot for the approach you fly right down to minimums, the NH pilot says "go-around - nothing seen" and you fly the go-around still on instruments, or as Non handling pilot you can concentrate partly outside (as well as monitoring), and be already in "visual" mode as you take the controls for the landing once you are visual. I have not flown for major fixed-wing operators in UK, but understand it is SOP at many of them - is it now also common in USA? The comment about "Standard phraseology" is very important - as an example, I recently read an account of an approach somewhere in Africa, poor vis (sandstorm), Handling pilot said "Visual with the runway", air traffic almost simultaneously asked were they visual ? , Non handling pilot said yes, they eventually realised that neither pilot was visual and got as low as 125ft on the missed approach. (This was a non-precision approach that had started its descent at the wrong place due to an incorrect Navaid position in the database) What had happened was the Handling Pilot had really been asking " Are YOU visual with the runway??", but the NHP took it to mean "I AM visual with the runway" :ooh: |
Farsouth;
We fly the monitored approach; it gets a bit tangled up with the "non-landing handling pilot and the landing non-handling pilot" when you read the ops manual, its been SOP in the last two UK operations I've flown on for the last 20 years. I believe it may have been in use at BA since the late 80's, in fact IIRC at BA the PF takes off, then the PNF flies the sector and the approach for the PF to land the beast, that way the PF (bloke doing the T/O and landing) has a head start on where that aircraft is in space as he's monitoring everything and not having to fly it at the same time. SND |
Sir Niall is right, in fact the 'monitored approach' has been used in BA and its predecessor BEA since the 60's. Having used both, it's the only way to fly.
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Unless it has changed in BA, 'PF' flies it up to TOD when 'PNF' becomes 'PF' (don't you love it....) and flies, as you say, to DA/H or visual.
It had to happen........I had 'one of those Captains' who briefed a full Instrument arrival, handed over inbound CPH (gin clear day, you could see where the field was at 100nm) and then said 'Visual, I have control' :) |
I'm sure I read somewhere that they were doing a form of 'Monitored approach' on Vikings in the fifties whilst flying Standard Beam Approaches. It was usual for the F/O to do the SBA and the old man to land it. The limits were impressively low too!
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BOAC
Unless it has changed in BA |
I think one of the points of the article is that there is a need to understand the visual portion of an instrument approach.
While there is a monitored approach for CAT 2 operations without autoland in the USA, a system of switching pilots at DHon a standard LS approach is not the norm. It is an accident waiting to happen if one pilot in a two piot crew does not ''play by the rules". I've seen a pilot say: Minimums or DH ''landing'' even when nothing is in sight...just mimicking by the rote method the published procedures/sop. IF you have a new airline, you better check your procedures. IF you have an old airline, go through things to make sure they really work. AT one airline, the MINimums calls are based on MSL callouts above airport/touchdown zone elevation. for many airports this is just fine...but there are unusual airports where it makes sense to only make the calls above published minimums. IF You call 1000' above touchdown zone elevation, then 500' above touchdown zone elevation, then 100' above mins and then mins/dh that's fine. BUT what happens at those odd airports where DH is 600 feet? 1000 above, 100 above, DH 500 above? unusual mins at Boston and REno make this a real problem. |
If you are doing this type of SOP in the simulator you need to be aware that there can occasionally be a discrepancy between the forward view through the first officers windscreen and that of the captain's windscreen. Thus one pilot sees the runway at DH while the other pilot cannot due to this simulator technical defect. The instructor sitting in the jump seat in the middle, tends to watch the approach through either the captain's or first officer's windscreen but not both.
At the subsequent post flight briefing, differences of opinion then may arise as to who saw what, when the whole problem was a simulator technical defect. As an instructor, next time you are watching through either windscreen whether a night VMC approach or breaking out at MDA in low visibility, make sure you test the intergrity of the forward view by leaning across where necessary to watch both views. |
Good GOD ABRA!
Surely such forward thinking would never have been allowed in this relaxed, progressive island of ours!! SND:E |
The SBA (standard beam approach) would lead a plane down to 100' above touchdown zone.
no glideslope per se, but the OUTER marker to the Middle Marker could be timed at just the right rate of descent to create a pseudo glideslope. a good example of it is in the book: ''fate is the hunter'' |
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