ADF needles float

[c402_cvs 0]

Like franky said, there's plenty that will interfere but normally with non of these factors around, especially during the day the needle will track pretty good, good enough to track a QDM of +-5 deg easily. FRED

[FSMP 95]

(1) Real World Two seperate things : ACCURACY & STABILITY (for want of a better singe word) The Accuracy is typically up to +/- 5 degs -- ie If the needle was not "jumping about", it's AVERAGE reading would be up to say +/- 5% Degrees in error. ( assuming no other Radio interferrance) STABILITY / DAMPING.The amount of "electronic" DAMPING appled to smooth out instability variations. If the needle is Mechanical, there is also going to be potential Vibration and mechanical inertia issues, affecting the stability of the reading. Typically the meter is INTENTIONALLY Damped, to reduce the rate of change of the display to some controlled amount. (2) Simulators Who knows ?? only those that code the Gauges.The BASIC NDB varaiable that comes form FSX is unrealistically STABLE and ACCURATE !!!Developers can then add Errors, Instability and Damping, as they see fit, to attempt to reproduce a more REAL World realistic display.Like most thing, this can be Overdone --- ( excessive Eye Candy -- just to show they CAN do it !! ) Geoff

[dverha 0]

I also noticed when you pause the sim during engine start, the N2 continues to rise??? Bug or and FSX bug?

No, this is completely realistic. In RL when you pauze during an engine start the N2 will rise to alarm you that it is very dangerous to pauze during engine start. A safety feature from Boeing, very neat. ;-) Kind regards, Daniel Verhaal

[c402_cvs 0]

I hope this is being looked at for the SP. I just tried an approach with a NDB as the MAP. It was impossible to know where I was in relation to it due to the wild fluctuations. Very frustrating!!FRED

[Flexman 30]

Real needles oscillate alright and sometimes a cloud with some static will render the needle useless, but in real life they don't oscillate so much when close to the station.

[c402_cvs 0]

Real needles oscillate alright and sometimes a cloud with some static will render the needle useless, but in real life they don't oscillate so much when close to the station.

Dude, here in my neck of the woods we do non precicion approaches ad nuaseum, I know how they behave in real life and it's not like this!!!!FRED

[Flexman 30]

Dude, here in my neck of the woods we do non precicion approaches ad nuaseum, I know how they behave in real life and it's not like this!!!! FRED

Last time I checked, that was pretty much what I said.

[DaveCT2003 1,820]

A little late, but I'm just going to chime in here. It depends on where you fly, the terrain and what it's made of, transmitter placement, whether or not the FAA and FCC paid attention AND got it right when authorizing the installation of another transmitter or tower, what you fly, your altitude, your NDB equipment on board (everything is not created equal). So many variables to consider, and as someone said, that's one of the reasons it's a non-precision approach. I"m sure that two or more different transmitters laying around can create some interested harmonics to fool with an NDB signal. Fun electronic world out there. Bottom line is that you CAN see swings of 60+ degrees (that's excessive), but you'll fly through it and it will change. Believe it or not, aircraft themselves CAN also effect this on certain frequencies, but that is often mitigated by design and antenna placement and tuning. Certainly a constant variation everywhere you fly is NOT accurate. If this was done intentionally (I haven't paid attention to it), maybe they attempted to approximate variation. To be honest, I've never shot an NDB approach in FSX, so I guess this is a challenge I'll have to look into. Be well, you fellow sim-head, techno types. :)

[i. cruz 0]

+1

[percylee 13]

This is no way close to real ADF needle movement, 95% of the time the needle is steady if not you could not fly a ADF approach. The needle should stay steady and no need to try to simulate any of the effects of ADF needle swing as this movement is small and random and serves no purpose.percy.

[bradrcfii 3]

I have never seen 30 degree swings on approaches in real life as a CFII. Maybe the poster tuned distant stations?

[percylee 13]

Normally if you can hear the code or broadcast you will have a good needle.percy.

[bpcw001 22]

I can also throw in my bit of real-world private pilot experience here.Not even our flying club's worn-out Cessnas and Pipers show this strong oscillation behavior on their ADF instruments.When you're too far away from a station, the needle will just point to an arbitrary direction, but it will do so in a stable way. When you get closer to the station, at some point the ADF will pick up the signal, the needle will adjust with a little bouncing and then stay more or less where it is and adjust smoothly to any heading changes. It does not necessarily point to the exact location (as we all know the problems with NDB accuracy, but if it points somewhere, it does so in a relatively stable way. I too think that the NDB/ADF oscillation behavior in the NGX is way overdone, especially given the fact that the antennas and instruments in a 737NG should be top notch quality.

[HiFly 16]

Seems the only ones who think this is RW are those who have never flown RW!!!!!! FYI, in the late 50's and early 60's the only Nav equipment most airports around the world had was NDB. They were accurate enough to guide planes from coast to coast with ATC almost non-existent except at major airports. And if you didn't have an NDB along the route you could use a radio station. The ADF could hone in on that signal, as well. As a matter of fact, AM stations were even listed on the charts back then. The only time (in 30+ years) that I encountered fluctuation is when signal was intermittent due either to a facility problem, faulty receiver, or to terrain interference. And the needle NEVER swung from right to left. It would usually just keep losing direction intermitently. Most of the time the needle was so steady that you had to keep Morris Code Identification signal audible to ascertain that you were still receiving the signal. Certain weather phenomena could sometimes cause a little vibration in needle direction but NEVER major oscillations! Up until a few years ago, many, many major airports used NDB's as "compass locators" ... because of the STABILITY of the needle direction pilots could use them as a reference when flying intercept to localizer, particularly when DME was not available! Many airports still use an NDB as part of an approach or miss-approach procedure -- often involving holding at a NDB. Pretty hard to do that in the NGX!!!! As far as reception, high level NDB's usually had reliable needle orientation as far as 80 nm and some even as much as 120+ ( for those of us in the flight levels ). Years ago, in order to obtain an instrument rating, a pilot would have to demontrate hand-flying proficient in using the NDB for enroute navigation, for approaches, and as a holding fix. And FYI, the reason NDB approaches are considered non-precision is that they do not provide a glide path signal. Nothing to do with this unreal oscillation simulation! I provide this information simply for RW clarity on the issue and in no way is this meant to offend anyone who may have voiced an uninformed contrary opinion.

[davidz 26]

Craig is damn right. No way you can know where your going if the needle is just swinging about and not actually showing you anything useful. Tolerance while tracking an NDB on an approach is 6 degrees - a bit hard when the needle never stays within 6 degrees!