Litjan

Thanks for helping me check this out! Cheers, Jan

Hi mfor, I think I need to sit down for a couple hours and go through all of the equipment again . Some bugs are still in there, indeed: I agree that the autothrottle should be failing with AC Electronic 1 failed - bug. - FIXED The yaw damper is listed at both the AC and DC electronic bus 1 in my documentation. The MCP should fail with the electronic dc bus, not with the regular dc bus - this is pretty unclear in my documentation and may have changed between versions. I think the electronic bus dc may only control the lighting... but with the plane in standby power at least the heading bug and CPT´s course should still work. Thrust mode annunciation fails correctly. Mach warning should fail with electronic dc bus, not with electronic ac bus - bug - FIXED A/P stab trim seems to fail correctly with electronic bus AC. Capt´s RA should fail with electronic bus AC - bug. I will see if I can fix some of these in time for the next patch... Cheers, Jan

I agree about the A310/300, it is certainly a great airplane. But I don´t think we will ever make an airplane that I haven´t flown (and liked flying!) myself, so that pretty much limits the choice of further aircraft we would ponder making to one.. Jan

Hi Tim, I think this is what is happening: When I look at the very first second of your video, I can see that you are in a peculiar protection situation - the barber pole (max speed) is still at 230 kts, which indicates that you JUST retracted the flaps, and most likely got into an overspeed situation where the autothrottle reversion mode is trying to prevent a flap placard bust. Hence the MCP SPD both in the autothrottle and pitch channel FMA. Once the flaps fully retract, the overspeed situation is rectified and the plane reverts to VNAV SPD climb. Why it does that I don´t know, it should actually go back to FL CHG climb. I would dare to say that the protection situation (reversion modes) is a bit of a black hole, and the flight manual isn´t very clear about those either. I don´t have much (any) experience with those in the real plane or simulator (I am proud to say). We have coded it to act like described in the flight manual, but it isn´t very clear on what happens when you exit the overspeed situation. I see that the plane goes back to MCP SPD and CWS P when you push the VNAV button, as expected. Try to fly the departure again and make sure that you don´t bust the placard speeds and see if it still happens. Cheers, Jan

Hi, I was never quite the elec-know-it-all when on the 737 myself, so these answers are a bit shot from the hip : The STBY PWR not showing AC frequency could be due to the pickup of the Standby AC-meter being on the inverter - which is not powered during normal operation. If you switch the Standby Power Switch to "BAT" you can see it showing AC frequency. The DC meter could be a bug - unless for some odd reason they placed the pick-up behind the battery switch (maybe to prevent draining of the battery, because the meters not only read voltage, but also current draw). As for what stuff fails exactly, bear in mind that some of the stuff in the cockpit is "default X-Plane" and may still work on our plane, even though it´s "real life bus" is failed. We tried to capture the most important users that would affect your flight, but had to draw the line somewhere. There is also quite a bit of detail-difference in the wiring between production versions, and the first 737-300´s delivered where a bit different electrically than the last ones off the production line. If you specify which equipment fails not correctly I will try to look it up in our code and see if we maybe hooked it up erroneously or if it is simply default X-Plane. Cheers, Jan

If you could capture a video of that I would be really interested to see it! Thanks, Jan

Hi Tim, that is really weird. VNAV can not turn itself on, really, and it can´t be "armed" either (unlike in the NG). So I have really no idea what went wrong there. We have the whole VNAV code slated for a complete makeover in the next few months, and this will likely cure whatever brought this phenomenon about. But for now rest assured that you did nothing wrong and probably just hit a weird quirk in our code. Cheers, Jan Edit: If you see the FMA column (on the very left) cycle during VNAV use (i.e. RETARD, IDLE, FMC SPD,...) this is normal behaviour during VNAV usage.

Hi Jens, you are right, the 28V DC Bus 2 should still be powered through TR3. I will investigate that with Tom. Thanks for checking so thoroughly, Jan

Thank you for the report! It will be helpful to stop these in the future! Cheers, Jan

Hi Carl, I think it´s simply a question of cost-effectiveness for the desired role. Two IRS units will also allow "averaging" of the position. In fact the FMC position is an average of all available positions, with a bias (in descending order) towards the GPS, the DME-DME, the LOC, IRS info and also VOR radial information. The classic was never ment to fly over the oceans or other remote areas and IRS units are crazy expensive... Jan

Hi Carl, there is a series of sensors that provide updates to the FMC position. The basis is the IRS mix position, but it will be updated by the GPS (which is the top priority), also the tuned LOC receiver (lateral update) and two scanning DME receivers that the FMC will autotune (indepenent of the VHF Nav receivers) to update the FMC position. The FMC will estimate it´s own accuracy (ANP) and throw an UNABLE RNP warning if ANP > RNP. We do not model deteriorating ANP, though - because we always assume that the GPS is available (which in reality mostly is). Jan

Please check which light is triggering the "Overhead" master caution. My money is on the OFF SCHED DESC light - this means that you have not reached your cruising altitude as set on the FLT ALT selector on the cabin control panel. Cheers, Jan

Hi MagicMandi, the position, direction, cone and intensity of the airplane´s exterior lights are controlled in the .acf (aircraft) file - this is correct. We believe that we have the lights "just right" - based on my 25 years (10 of those in 737´s) experience in flying jet airliners. Most of the default aircraft in X-Plane have lights that are too bright. The taxi-light´s purpose is not "see where you go" - it´s more "be seen when you go". You can also spot obstacles on the taxiway, but not out very far. The light is not intended to illuminate the taxiway. The reflections are not part of the flight-model, as they do not influence the way the airplane flies. The cockpit display reflections in XP11 are a new property (as far as I know), so we can not apply them to the XP10 model. We do, however, already have a makeshift reflection in place for the XP10 version. Cheers, Jan

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That is correct, good catch! Thanks, Jan Edit: And fixed for next patch.

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Hi jojo, We have a bug where the gear sound is actually connected to the lever - not the gear position... I hope that I will get some dev-time to fix it for one of the next versions, but it is fairly low priority because in "normal" operation you will not notice. I think we may also have coded the gear to only deploy manually when the gear lever is in OFF - so it won´t deploy when the lever is down...and when you move it to "UP" it will pass through the "OFF" setting, which drops the gear, then. We may revisit this in the future, too. Thanks for your report, Jan

I am unsure what your problem really is. I see these values on my system with XP10 and XP11. Oil pressure is certainly well above the red mark, and when I advance thrust for take-off power, it is well out of the yellow range as well. If you don´t see this on your system, you may not have set up the plane in XP11 to work correctly (a tweak to the .acf file is needed). If you are not getting oil pressure above the red limit check for a failure in the X-Plane failure menu - not sure if there is a failure like that, though. Jan

Hi "jolmos", The hydraulic system is not indicated on the gauges you show. The gauges depicted show the engine oil pressure for the engine lubrication system. The limits are: minimum 13psi (above red mark), do not take off with oil pressure in yellow band while take-off power set. Cheers, Jan

The real nosewheel goes full left to right very fast, too - thats why you move the tiller or the pedals slowly and deliberately. It´s easy to knock the flight-attendants out of their shoes when taxiing carelessly, and then be prepared to go hungry and without coffee for a few days... Jan

The taxi behaviour over 3 kts groundspeed is unchanged from XP10. Jan

Find the distance and direction, point your nose and push the thrust levers forward!

Hi Oliver, the T/C is calculated when you press the EXEC button - and then it remains static, even if the airplane climbs much better (or worse) than expected. It is rare to reach the top of climb at exactly the precalculated point in the real airplane. Whenever you do a recalculation (like flying direct to a waypoint, entering a new climb speed, etc.) that requires you to hit the EXEC button, the T/C will be recalculated. In the real plane the T/C symbol will also disappear as you fly past it, this does not happen (yet) on our model. Cheers Jan

Thanks for the info - the PROGRESS page is pretty much a work in progress and will be improved and finalized in a future FMS overhaul. Cheers, Jan

Hi and thanks for the video - I think the problem is the turbulence - the PID algorithm may be fooled by the up and down of the airspeed. We did some adjusting for a similiar problem during MACH climb... but will look at this again. In the meantime I would suggest to use FL CHG with MCP SPD instead of MACH - it might track a bit better. Cheers and thanks for your help, Jan