E/D wrong altitude

[FirstOfficera320 1]

Thanks for all the help, guys. As I said, I'm just starting to fly NPA's, s I don't know much about them. So just to be clear, I would let VNAV take the plane to the MDA, then disengage the autopilot and land manually, right? (and I should be at VRef at that point, no?)Just one last thing--could somebody give a quick explanation of IAN? I found some info online, but not a whole lot, and considering the information I found on VOR/DME approaches was apparently insufficient, I want to be sure I know what I'm doing.Thanks!

Hi,Here is a quick guide (bear in mind I fly the airbus A320 so these are sort of adopted, but works in the sim like a charm)This is for the full IAN (Integrated Approach Navigation) and it assumes you follow the magenta line. If you are being vectored, just make an extended centerline.1) In cruise prepare the approach in the FMC and brief it. Set minimas and crosscheck accuracy. Also get the weather and preset the QNH. Decend is like a normal ILS.2) 15nm prior to touchdown start reducing towards Vapp. Extend flaps and gear on schedule.3) when cleared approach. Press APP this arms the IAN. On the FMA you should see FAC / G/P as armed.4) Monitor raw data as the A/P couples to the IAN. This goes both for the horizontal and vertical flight path.5) at or before MDA if runway in sight. decouple the autopilot and autothrust and manuouvre to land the airplane as normal. Do not duck under.I think this covers the basics. Feel free to question me :)Regards,

[boeing247 0]

All right, sounds simple enough. Two questions, though--first, since there's no glideslope, what does pressing APP do? Also, will this set me up on a correct glideslope, or will I likely have to adjust my V/S?

[NoahBryant 26]

The plane "creates" it's own glide slope based on the nav data it receives so there is a GS to follow, just not the same kind as with an ILS.And again - try to get out of the frame of find about thinking about vertical speed in an approach - it doesn't tell you anything important unless it says something like -2000 which means you're in a bad spot, lol. Watch your speed always and your altimeter/nav instruments/heading etc until you can see the airport. Once you see the airport your eyes are your navigation and you just need to maintain the correct airspeed.Let's say you were a bit high - then you would need a slightly higher descent rate to line back up with the GS. Well the VS gauge isn't telling you this it's your eyeballs/altimeter/GS. What your VS winds up being is inconsequential.Also you're pitching for speed and using throttle for altitude so if you're slightly high, you're not pushing the nose down but you're slightly decreasing the throttle. This will (assuming you're trimmed) cause the plane to descend slightly faster to maintain the correct speed. Once you're approaching the correct altitude slowly add a little more power for the opposite effect.

[jakef 2]

Ok I'm going to take a stab at this. I think the real problem in this case is with the navdata. This is one of those rare occasions where real world data actually messes the NGX up. Lets take KSEA as an example. The wpnavapt text file in the navdata folder says:SEATTLE-TACOMA INTL KSEA16C09426163 47.463808-122.310986111.7016300430SEATTLE-TACOMA INTL KSEA16L11901163 47.463795-122.307750110.3016300433SEATTLE-TACOMA INTL KSEA16R08500163 47.463836-122.317858110.7516300415SEATTLE-TACOMA INTL KSEA34C09426343 47.437970-122.311211111.7034300363SEATTLE-TACOMA INTL KSEA34L08500343 47.440533-122.318058110.7534300356SEATTLE-TACOMA INTL KSEA34R11901343 47.431172-122.308039110.3034300347It should read:SEATTLE-TACOMA INTL KSEA16C09426163 47.463808-122.310986111.7016300433SEATTLE-TACOMA INTL KSEA16L11901163 47.463795-122.307750110.3016300433SEATTLE-TACOMA INTL KSEA16R08500163 47.463836-122.317858110.7516300433SEATTLE-TACOMA INTL KSEA34C09426343 47.437970-122.311211111.7034300433SEATTLE-TACOMA INTL KSEA34L08500343 47.440533-122.318058110.7534300433SEATTLE-TACOMA INTL KSEA34R11901343 47.431172-122.308039110.3034300433The red numbers at the end of each string are the threshold elevation in feet for that runway. The default airports in FSX do not have slopped runways, all runway thresholds will have the same elevation as the airport elevation. Without accurate numbers (accurate for FSX) the FMC will not calculate a proper E/D.

[FirstOfficera320 1]

Hi Bram,I just flew a NPA approach and took some screenshots for you. this was the first time for me, in a long time, that I followed the LNAV and VNAV path all the way from takeoff to landing.Here we are cleared for the approach. APP has been selected. IAN has armed.Intercepting the Final Approach Course or FAC. Also note the VOR pointers on the ND showing us pointing in the right direction and within margin.Fully established on our FMS made "ILS" approach. The database was a little off so I am actually a little above the profile depicted on my approach chart. Actually what I should've done is followed my chart's altitude and disregarded the IAN. These are the small deviations one has to live with in the simulated world. luckily the weather was VMC so I could manouver visual with the HUGS and PAPI.Kind regards,

[boeing247 0]

Thanks so much, that clears it up! But just to be sure--IAN arms when you set the pitch mode to APP, right?