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Guest psouthan

I'm always to high on approach (not on drugs either)!

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Guest psouthan

I am still, after many years, working my way towards flying the 737.I am almost there but I seem to be always at least 3000ft to high on approach. I set my QNH accordingly but is there something I am missing?Help AppreciatedPaul

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Guest tango_d

Hi,I think more info is needed to help you.Are you flying instrument approaches ?FMC programmed ?VNAV ILS Landings etc etcRegardsEddy

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Guest psouthan

Hi Eddy,thank you for your reply. In general I tend to attempt ILS approaches. I always get lined up up ok but it always seems to be too high and then at the lst minutes I change to Vnav approach and manully attemt to enter my Vertical speed which inevatable is almost always wong and I either overshoot the rwy or don't make it.RegardsPaul

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Hi Paul -Maybe a dumb question from me -Are you setting your NAV2 radio for the ILS freq during an Auto Approach/Land? If so are you using both CMD A and CMD B on the panel? Along with APPR?Just curious, unless you are doing something totally different then disregard.Cheers,-RobCaptain Delta VA737-8/900

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Guest psouthan

Hi Rob,Yes. I am setting both nav frequencies and using both CMD A & BI think it has maybe something to do with the QNH on landing. I use Active sky but i always note the current QHN below the transition altitude. What is the baro for is that perhaps causing it?Thanks for the replies guys.

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Press "B" key when below the transition altitude and it will automatically set your Barometer(Note I do this about 3 or 4 time prior to landing depending on the situation). If you are not doing this at this time then I can almost guarentee this is the problem.

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Paul -I'm using Active Sky 4.5 also. Usually on approach I'll set the ALT, but not mess with it until landing. Is the NG staying above the glideslope? Do you see it capture or track? Just to make sure, you are performing an Autoland/Approach? I don't want to be in the wrong ballpark :-)Cheers,

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Guest psouthan

Hi Rob, Yes- I am attempting ILS landings. I think the prolem revolves around one or two things, based on the feedback I a getting 1. either its the baro or 2 I suspect morelikely, it is something to do with the altitude settings. Sounds dumb I know but should I be setting the altitude to the aiport elevation or some other altitude? For example missed approach altitude? Moreover, on the over head panel there is an altitude setting for landing ...is this just aesthetic or function?Thanks again for your helpPaul

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Paul,You should be setting the Missed alt but this will not change your problem. The altitude settings in the overhead are for your pressurization, again this will not fix the problem. If you are not setting the barometer to the correct setting then the aircraft thinks you are at a different altitude than what you are actually at. Once you press the B button it will automatically dial the correct setting for what the current Barometric pressure is.

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Paul - As far as I know the aircraft uses radio height for autoland procedures and shouldn't be affected by your baro setting. This sounds like something different. We need more information to pin-point your problem. Can you provide some screenshots? I've seen this problem mentioned before and if I remember correctly it boiled down to speed issues.Once the ship reverts to G/S pitch mode the MCP altitude has no effect and should be set to your published M/A altitude.Hope it helps

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Guest boxjockey99

Not sure if this will help but here's a simplified method of how to do things. Basically its the way we do it for real in the 300 series aircraft I fly at work!I'll try to make this as concise as possible!During the descent set up your bugs (speed -Vref30/Vref40 and decision on both barro and rad alt), bearings (the inbound course for the desired runway and both nav boxes to the required ILS frequency) and brakes (set the autobrakes) that should cover you for all the key mishaps! Ideally I plan to be at 3000ft above ground by 10 miles from the field with a speed of 180kt and flap 5 selected.Once on an intercept heading for the LOC arm the VOR/LOC mode. this is usually where I dirty up to the above mentioned flap 5 speed 180 config. as the aircraft intercepts the LOC just check you are still below the glide slope ideally the glide should still be at the top of the scale. YOu should arm the APP mode now and ensure you get a white G/S on the PFDFrom here on all your cues to do stuff is based on the rad alt and the glide slope needle. As the G/S needle starts to move select GEAR DOWN and FLAP 15, SPEED 150ktAs the G/S reaches 1 dot above centre select FLAP 25 SPEED 140 (or VREF +5 whichever is higher)As the G/S reaches 1/2 dot above centre take the landing flap (30 or 40) and SPEED Vref30 or Vref40 + 5ktThe G/S will capture very soon after and you will be nicely set up for the approach. Once the APP mode is armed you can select the second A/P but if you haven't already now is a good timeThe aircraft will descend on the glide with a 'SINGLE CH' caption in the PFD until it passes about 1500ft Rad alt. At this point the G/S and LOC scales will flash as they do their internal integrity check, if this is successfull (always in the sim) you will see the 'SINGLE CH' caption go out and the second autopilot will be engaged. Note that nothing will actually change on the MCP as you had already selected the 2nd A/P, all this check does is basically allow the 2nd A/P to make inputs whereas before it was engaged but inhibited by the computer (longwinded I know)Passing 800ft RA check you have a white 'FLARE' in the top of the PFD. If it ain't there then you have no FLARE mode and basically have no autoland so will need to land manually!Passing 500ft check everything is still on the numbers!at decision ... well decide if you can see enough to land! at 37ft RA the FLARE mode will activate and the thrust levers will retard. the aircraft will impact the ground and the A/THR will disconnect but YOU must disengage the A/P manually and ensure you keep the centreline. Thats it basically. The trick is to be at a sensible height at a sensible distance, ie being at 6000ft at 10miles would be WAY TOO HIGH and you would have to throw the approach away. Being correctly configured will help you also. The flap 5 speed 180 config prior to intercepting the LOC will help as the A/P doesn't really like a high speed LOC intercept unless you are way out. Hope that lot helpsas always feel free to ask questions, between Brad and myself I'm sure we'll sort your problem, screenies would help though!RegardsKris

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