Morten

Hi guy's, been a long time Regarding rotate feeling light, this is mostly an XP issue (at least in XP11 that i knew well). In short, the 737 has a supercritical airfoil (NASA term, or "aft loaded" airfoil as Boeing calls it). One of the differences between conventional and aft loaded airfoils is (as the name implies) that the aft loaded airfoils have the center of pressure further aft. Meaning also the center of lift is further aft than on a conventional airfoil. XP does not model this very well, and as far as I know has its center of lift at the 1/4 chord. So this means XP airliners have their center of lift too far in front which cause problems in the transition phase between ground and flight. Should be a fairly simple fix for Austin. There are some temporary "hacks" one can do, but it's a can of worms... Good to see the old girl in the XP12 skies - great work Jan and Tom

Anyone made John Travoltas new toy yet?

Regarding speedbrake drag, it was calibrated using the real drag data from boeing. (Jan might have adjusted it later) It depends on Mach and Cl (aoa). Gives an increase in Cd between 0,011 - 0,014 in the normal envelope, so not much..

An ancient X-Plane advice: Are you seeing odd behavior of any sort that you cannot explain - delete the XP prefs files

From behind

...and make sure you are using flattened airport terrain before making any judgements...

On the contrary, lift increase starts at about one CHORD altitude were you need ease off on back pressure (after the flare/break). Pitch down effect starts about 70' agl. We have analyzed dozen's of real B733 landings based on real FDR data. Attach a sample of a few real B733 landings for you. As Jan says, we had these discussions with Austin many times and provided various documentation. So the combination of science, real data, NASA test data and Jan's extensive in type flying experience has given us the result we have today which is the best for any desktop sim.

Maybe it has something to do with how you set up your trim? You using a keyboard key for that? Any other tasks (data refs) assigned to that same key maybe? Try configuring your controls again again, using another key..

CG (e.g if far forward) will also affect pitch

Hi guy's, rainy day here today so had some fun making an IXEG face for those of you that are using an android smartwatch and the Facer app. The fun part is the N1 fan is spinning My first attempt at this so let me know if it works ok https://www.facer.io/watchface/7cGemLBcC0

Very interesting indeed. At this point it's a bit hard to say what exact impact it will have on flight model. Trim, controls, feel are likely to get affected which are not a big deal, but if it messes with total lift - which is likely - it will require a major overhaul.

And with those words, we close this topic and wish everyone a nice weekend. The aircraft will get further updates, we apologize for the delay which is mainly a result of us doing this a as a hobby besides our "real" jobs.

Well, there is a sharp line between criticism and insults. When someone tells you what you have been working hard on for 7+ years is worth nothing, that is an insult. It is all about choice of words. But as you say, those people who react in this way usually have had a difficult past/life or really bad day.

And most of those we have been very open about. If things go as planned we will have an update ready later this year that will address a lot of VNAV stuff and more. You are off course entitled to your opinion. We have however thousands of very satisfied customers, and the IXEG is one of the most flown aircraft in X-Plane according to Laminar statistics (actually flight time). We have dozens of real 737 pilots flying it and reporting it to be overall the most realistic simulator aircraft they have ever flown! Can it be improved in some areas - off course - and it will be.

Sure, just mention that it is based on the default one.

Nice find!

I guess anything can be called "major" depending on who you ask those are on the to-do list

Hi Marco, welcome! Sounds like you got wind coming from the side? Check the wind indicator on the map display when in the air. M

Used to work fine in XP10, although been a year since I tried. Sounds a bit on the low side yes, at that weight you should drop below 1000fpm around FL300. You have off course checked you do not have any ekstra drag out, like accidentally extended the gear, flap or spoilers. Lately we have also seen examples of 3rd party plugins that are somehow messing with flight model (should be a law against that) So try disabling all other plugins and try again.

Don't remember, possibly on the wing.png

Maybe your brake hardware is sending/spiking signals, which will deactivate the auto brake..

No, as Jan just stated as a pilot, and I as an engineer, overall the effect is really good as we see it, but might need a *slight* adjustment.

.... and should you contact Austin, I recommend you first read up on this document as this is what he uses as a reference. Ground effect downwash.pdf

Aircraft that do not have a nose down effect, are most likely still using the OLD flight model of X-Plane! To know you need to have a look inside the airfoils and aircraft files. I suspect IXEG to be one of the few that are using the new flight model atm (which overall is much more realistic). It does not matter if it's the "latest" version of XP or the aircraft, it is up to the designer to implement it or not! ALSO, everyone needs to understand that how much nose down effect WILL VARY with aircraft type/geometry/wings High tail/low tail: An aircraft with a high T-tail (type MD80) will have less or no pitch down at all. High wing/low wing: An aircraft with a high wing low tail (type C172) will have a lot of pitch down A wing with a high L/D ratio or high incidence is likely to have more pitch down A long fuselage aircraft is likely to have less pitch down than a short of the same type (Type 737-800 vs 737-700) A low AR (long chord) aircraft is likely to have more pitch down than a low AR When the effect starts depends on span, so a B738 and a B733 decending at the same speed (700 fpm) will enter the effect at different altitudes, the B733 at a much lower altitude so it will "seem" a lot more dramatic to the pilot as you are closer to the ground. An aircraft with more swept wings will be likely to have more pitch down as the wing tip will create more lift as it enters and center of lift moves back An aircraft with winglets is likely to have less pitch down than one without. etc. So Rob and Andrey, even a real B738 pilot cannot predict the nose down effect of a B733 unless he has actually flown it! So the one to listen to with regard to the IXEG 737 is Jan - as always As you can see, comparing aircraft in ground effect is pointless, and this goes for the other types of ground effect as well. This is what makes this area really-really complicated. What you can be sure of though is that XP does this really well. M

Also note that if you have XP's pitch control sensitivity setting set to a HIGH % (more non-linear), you will need to input MORE elevator to counter the pitch down tendency in ground effect! Our recommended setting is 25%.