cckohrs

I think SP1d does not really exist and this and related threads have been an elaborate sales drive for ASN and P3D. I'm guessing it worked (did for me for ASN). :rolleyes: I'm worried when Rob uses words like "planning", "one minor detail" and "expect"; what if I hit thunderstorms this weekend and I don't have a weather radar on my NGX... Guys I'm excited. Can't wait. Thanks for the update and keep them flowing; it helps a bit. Carl Kohrs

I think the HDG warning came after I did a magnetic declination update (as per the PMDG general forum post) so maybe it has something to do with that. Otherwise I am out of ideas, and can only revert to the standard fixes of reinstall, etc. Good luck, let us know if you find the solution. Carl Kohrs

Ok I think I'm missing something then. The picture of the ND looks perfectly normal to me, except for the fact than you are saying you align heading and it goes to the left, and that there is no crosswind. Also sorry for missing that you did not have a cross-wind. On the ILS course, you do not need to be flying an ILS approach, just have an ILS frequency tuned. From your screenshot it looks possible, looking at the frequency on the standby radio set and the DME display. Once again I may be totally wrong here, I'm not at home to check my facts on the J41.

Also, unlike the NGX (in some configurations), the J41 HSI shows aircraft heading and not track. I see from you screenshot that you have LNAV engaged as roll control. Therefore, the reason for the "misalignment" is simply a crosswind. The autopilot is flying the FMS route, and your heading bug is only there for standby. I have never seen the C on the AH. So I don't know what it is. Carl Kohrs

I had the same HDG warning a couple of weeks back. I may be totally wrong, but I THINK it was because the set course for the HSI is not the same as the ILS final course. I only saw it once, so can't be sure. Carl Kohrs

I have sometimes found that the FMS doesn't point the plane in the right direction because it doesn't have the sequence correct in its own memory, even though the order is correct in the FPK page. Make sure that it shows the correct waypoint on the NAV page (use direct to function if not). For a couple of minutes before you reach a waypoint, the NAV page displays the NXT (next) waypoint. Does the plane actually turn where it says it will be going? Another possible problem: i have seen some stars (maybe sids as well, but haven't spotted it myself) where a waypoint in the navigraph data is stored as e.g. "until 20dme (a certain VOR)". For some reason, the Jetsream FMS interprets this waypoint as the specified VOR, and not the point at 20DME. I have not found a solution to this problem yet. Carl Kohrs

I agree with Frank, it's the condition levers. The start locks keep the props in the fine position (to allow the starter motors to turn the engine with enough speed to allow startup, feathered position would cause too much drag and the starter motors will not be able to turn the engines fast enough). The condition levers control the rpm, not the start locks, but due to the fine position, the engine can not generate thrust or torque (the prop blades cut through the air at a low angle of attack meaning low "backwards lift" or thrust, and low drag on the blades, meaning low torque). Now, since the engine controls dont allow the rpm to go more than what the condition levers are set at (generally) and the torque generated by the engine is low, the total power generated by the engine is low (power=torque x rotational speed) and therefore the heat put into the engine, and resulting EGT are also low. The position of the start locks can therefore not cause and overheated engine, it just means you are not going anywhere since the prop blades cant be "turned back" to a courser setting to allow the thrust to increase. On a turbine engine, especially turboprops, the speed of the engine has a large part to play in the amount of air that goes into it. As per the manuals: more air means more mass flow to be heated, meaning lower temps overall. Less air, conversely, means more temperature. If you read the manuals, you will learn that, unlike the free turbine turbine turbo-props (think King Air) the engine speed and prop speed on the J41 engines are directly related, since they are geared together. On the free turbine engines, you can change the prop speed with the rpm lever without bothering the other shaft (I believe it's called the high-pressure shaft) too much (there are two seperate shafts, google it for pics). Not so on the geared turbines, where engine speed and prop speed are directly related. Therefore, if you change the prop speed using the condition levers, you are changing the engine speed as well. Lowering the props speed, therefore, means you increase the metals temps in the engine as there is less air to be heated by almost the same amount of fuel. Trying to take off, i.e. giving full power, at low rpm, means that you put too much heat into the engine for too little air and the engine melts, or catches fire. In my opinion it's the condition lever. Move them to the "flight" (full forward) position before you start the take-off run. Also, do not jam the power levers all the way forward. The engine is capable of producing more power than what the metal can handle in terms of temperature. General practice is to move the condition levers forward to around 80% and then inch the levers forward slowly until you reach you desired torque for take-off, or 100%, or you reach the egt limit. So during your take-off run, keep a close eye on the engine guages. Remember that turbine engines dont respond as quickly as piston engines, and turbo-props are slower than turbofans as well, so you must set the power carefully. Be ready to pull back on the power if you overcook it, but best practice is to do it slowly and never exceed the egt limits. Remember, any additional thermal stress on the engines mean you run a greater risk of unwanted trouble later on, and your maintenance bill will increase. To the casual simmer, this is obviously not a problem, you just want the kite in the air without a tail of fire. However, looking at the long-term wellness of the plane will aid you in keeping it happy in the short term as well, if I may be a little philosophical. Alternatively, you can swith the engine fires off in the config manager (run it as admin otherwise it may not save your changes), but to me, the is no sense in paying for this quality of an add-on if you are not going to learn to fly it properly. Last word, read the tutorial, and fly the tutorial flight. It is not as daunting as it may seem, and it will add greatly to your enjoyment of this lovely airie. In my opinion it is better than the NGX to fly, as it keeps you on your toes, for example: our current discussion. Hope this helps. Carl Kohrs

OK so I've done a defrag and did a flight with clear skies: no change. I'm wondering whether I'm expecting too much. I seem to remember clearly it aligning perfectly with the LOC with (as mentioned) no overshoot AT ALL. But maybe I remember incorrectly. It was my first add-on and I was still trying to get my head around the sheer magnificence of it that a very slight overshoot seemed perfect compared to the stock-standard FSX wrecks I had flown before, which seem like they barely stabilize on the LOC before touchdown. How do you guys find it? Does it get on LOC without any overshoot and stays nailed to the LOC and GS all the way down? Does it overshoot alt's on autopilot, or lose about ten feet in turns, or does it stay perfectly on the desired alt? Of course on all of these I am asking considering the limitations of the plane, i.e. I'm not asking whether it overshoot from a 4000ft/min descent. Basically: am I being too hard on the bird, or am I picking up something slightly out of the ordinary? Carl Kohrs

Will give the calm weather a try as well. No weather add-ons. Really, its just the NGX, J41, FS2crew for both and Ivap. Does anyone have any suggestions on the legality, advisability of playing with the autopilot controller gains? Carl Kohrs

Hi. Thanks for the hints. I will try a defrag, haven't done one in a while. Intercept speeds and angles are the same if memory serves correctly, also, I do not believe these can be the only culprits as I believe the problems are related to the way the PID controller controls the plane, as it seems everything is slightly off; I did a quick check again and I even get overshoots on ALT SEL. It would slow down close to the selected Alt, but not stop completely and go to 10 or 15 feet above. If this is the case, I guess my system performance may be the issue. It is possible that if there are fewer resources, the PID controller error check iterations rate are reduced and then it will take longer to correct errors, and may even result in overcorrections, which will explain some of the behaviour seen before my FSX rebuild. Will give it a try and if it works I'll mail you a beer, because this has been bugging me a while now. Carl Kohrs

I've been enjoying the JS41 for just over a year now, but something has come up that is a bit annoying and I would love to be able to fix it. In the beginning, I was amazed at this bird's autopilot system. I would intercept the LOC (on a reasonable intercept angle) with absolutely no overshoot and it would track the LOC and GS down to the DH without even a hint of deviation on the needles, literally none to be seen. At that stage, the Jetstream was my only add-on apart from IVap client. These days things aren't going so smoothly. The GS tracking became worse up to the point where it would deviate up to 1 "dot" close to DH. A few weeks ago I did an FSX rebuild and things are looking slightly better, but not as good as in the beginning; I still see a bit of an overshoot even on normal LOC intercept angles and there are small deviations on the GS needle. Things I've added to my FSX since starting with the JS41 is the PMDG NGX as well as FS2CREW for both the NGX and the JS41. I run a pretty standard FSX apart from that, as my rig is pretty old, I run on low settings for the most part except that which is needed to get enough out of the wonderful cockpits of these PMDG planes. So my question is: what could have changed to make the JS41 behave slightly less perfect than it used to? I've had a look at the aircraft.cfg file and it looks like the autopilot gains are user changeable, although I would really like to avoid this approach as I do not want to mess with what PMDG has gifted the Simming world (and they may frown upon me messing with their control design). Messing with these would also mean a lot of experimenting which I would rather avoid. Carl Kohrs