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RobbieHe

how to perform correct GA procedure

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Here's my scenario:I am approaching KSFO 28 R in a Land 3 autoland. I have my holding pattern programmed in the FMC. Now, according to the Level D 767 Angle of Attack DVD, the GA mode is automatically armed when flaps 1 is selected - when the G/S is intercepted. However, on my scenario, when I select flaps 1, there is no indication that G/A is armed. Also, in my scenario, after I have selected flaps 1 and pressed the G/A mode does not commend the AFDS autothrottle into a 2000 fpm climb (it's more like a 200 fpm climb).So, in my given scenario, how to I perform a correct autoland (using the autopilot commands).Thanks,RH

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Funny Robbie I've been getting more procedurally active with the LDS 767 lately and i'm also looking for an explanation on go around procedures, I think this topic would be better placed on the official level d forums. I'd love to see what they say in regard to it. I was reading topics of a similar vane on there and I understand that go around procedures vary depending on what mode you are in ie manual, full autoland etcGeorge

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I went ahead and placed in on the unofficial LevelD forum here in hopes of a response. If I don't get one, I'll put it up over there. Procedural is the only way to go now, but, man, does it ever take time to learn! I think once I get the go-arounds to work, I will feel much better. I am going to learn via autoland first and then how to do it manually. Sounds kind of backwards, eh?RH

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It's been a while, but among other things did you dial in your missed alt on the MCP after G/S active? Did the command bars rotate?scott s..

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It's been a while, but among other things did you dial in your missed alt on the MCP after G/S active? Did the command bars rotate?scott s..
No, I did not dial in the missed alt in the MCP. I did not know I had to since the hold was programmed into the FMC. But now that I think about it, you might be right (or probably are right). I am not quite sure what you meant by, "Did the command bars rotate?"Thanks,RH

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..."Did the command bars rotate?"...
He's referring to the pink bars on the flight director seen on the PFD. These command pitch and yaw (indirectly roll). He's asking this to figure out where the problem is. If the command bars moved to indicate a go-around attitude, the the FD got the message and just isn't passing it on to the FCC's in autoflight. If they never rotated, then somewhere the computers are not getting the message to go-around.Now, let me see if I can help with the go-around procedure. It's been a while on the LDS 763 though, so a few parts mught be rusty.Let's say you start off 30 degree offset from the localizer, cleared for the approache at 2,700' MSL (I'm thinking ORD procedures since that's what I'm most familiar with). You'd select the LOC mode and slow to whatever your intercept speed is (usually 180-210 kts) and intercept with 5 degrees of flaps. You should see "LOC" appear under "HDG SEL" in the lateral navigation annunciator of the PFD. At intercept, LOC should replace HDG SEL and your aircraft should turn for intercept. Once the localizer is within one dot and you are within 10 degrees of final heading, you are officially established on the localizer and would select APP mode. Again, G/S should appear under ALT HOLD on the PFD, but it should be in the vertical navigation category. As G/S comes alive, slow to final approach speed and get the gear out. Once you have intercepted the G/S, this should replace ALT HOLD on the PFD and you should reset your MCP altitude to the missed approach (4,000' MSL at ORD). This is necessary because the MCP sets hard limits on descents and climbs. The autopilot will never descend below or climb above the MCP altitude regardless of what is entered in to the FMC. At 1,500' AGL, all three autopilots should engage--if not engage them. You should then see LAND 3 in gree and under lateral and vertical modes on the PFD you should see rollout and flare listed respectively. If you actually land, your done until reverse thrust on TD.At any point, a missed approach procedure is intiated by selecting TO/GA mode. On real aircraft, these are buttons on the throttles, but I believe it's activated by the N1 button on the LDS MCP. Your aircraft should go to full N1, pitch to maintain approach speed + 10-25 kts and climb. Lateral and vertical navigation on the PFD should read LOC and SPD respectively. Some aircraft immediately retract flaps (747 goes to flaps 20 immediately), but I believe the 767 simply retracts on schedule for speed. Obviously, gear come up as soon as you have postive rate. Most missed approach procedures have you climb to some altitude on runway heading (like a standard climb to acceleration height on takeoff), and then head off to intercept a hold. Once you reach this altitude, if the FMC is programmed fully, the FD should change the speed from approach + 10-25 up to 240-250 kts (limit under 10k). Vertical mode remains speed and lateral mode should switch to an appropriate method such as HDG SEL, or more likely LNAV. At this point, your job is to monitor the aircraft and retract the flaps on schedule--and obviously communicate with tower. Everything else should be automatic.Now, you also mentioned the concept that TO/GA mode is activated whenever you select flaps 1. This refers to the N1/thrust control maximum. The FMC and FD set limits on maximum thrust throughout a flight. So during takeoff you can always use up to 100%, in climb usually up to about 95% and in cruise/descent usually about 90%. The pilot can always over ride this, but normally this is not necessary. So as you're descending the computer is telling the engines to never spool above 90% or so (whatever the CRZ setting is). This is not good for a go-around though. So once you select flaps 1, you're telling the computer that you are getting ready for landing, please make 100% of the thrust available in case of a go-around. This is what flaps 1 activates. The same thing is accomplished by pushing the "TO/GA" button on the thrust management panel. All this does is tell the computer what the maximum amount of thrust is that can be used from the engines. It does not ativate a go-around.But since you bring this up, how do you know if this mode is armed? Above the N1 readouts on the EICAS MFD, you should see in green letters/numbers you maximum thrust allowed and thrust mode. So you should see something like "105.1" above each engines N1 guage and then see "GA" indicated between these two numbers.Retracting to flaps 1 is a bad and dangerous way to intiate a go-around. You're approach is being flown well below Vmin for flaps 1 and retracting without an increase in speed (and the needed increase in thrust to get that) places you in eminent danger of stalling.I know it's long, but hopefully this helps at least some. Discussing how to enter the approach in autoland may not seem related, but this is all important because as you pass each step you're essentially making a "GO/NO-GO" for landing and missing any of these may cause failure of down stream portions to activate

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