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INS / Navigation Computer tutorial (video)

Posted: Sat Jul 11, 2015 8:58 pm
by wiltzei

Re: INS / Navigation Computer tutorial (video)

Posted: Sat Jul 11, 2015 10:51 pm
by WarHorse47
Nice vid. I think I've watched it at least four times to figure out what I'm doing wrong.

The only thing I noted was that despite putting in accurate lat/lon for my present location, I get the blue sync lights when I switch the Nav Computer to stby. Once I switch to Tgt1 or Tgt2, the lights are off.

I can get the INS to ALIGN and turn off the warning light in the front office, but the HSI takes me in a total different direction than expected (270 degrees vs. 25 degrees, for example).

--WH

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 8:53 am
by JonathanBleeker
You sure about the target coordinates you entered?

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 2:04 pm
by WarHorse47
JonathanBleeker wrote:You sure about the target coordinates you entered?
Yes, pretty sure. I'm using a printed reference. I just sent you an e-mail with more detailed explanation.

--WH

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 3:46 pm
by gulredrel
Maybe your HSI thing is related to this problem?
http://www.milviz.com/forum/viewtopic.php?f=101&t=5202

You could check current position and changing of it during east/west course.

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 6:11 pm
by JonathanBleeker
Ok I am unable to replicate the problem of the needle pointing the wrong direction. This does have me wondering...Rear cockpit or front? In the rear, the bearing to target is indicated by the number 1 needle (the thin one) and the no.2 is ground track. In the front, bearing is via the bearing pointer (little arrow on the outer ring with the heading bug) and ground track with the CDI needle/arrow.

Or you were in TGT 2 which had different coordinates to what was on the counters and led you in a different direction than expected.

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 7:07 pm
by WarHorse47
Okay. Here goes...

Here is my ride

Image

Everything is programmed into the Nav Computer and the INS has been aligned

Image

Boeing Field should be 25 degrees to the North, but look at where the instruments are pointing.

Image

Image

Instead of directing me North towards Seattle, I'm being directed West over the Olympic Mountains.

--WH

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 7:20 pm
by JonathanBleeker
Zoom in on the nav computer please. I cant tell for sure but I think your TGT longitude is indicating 122 deg EAST (E) rather than 122 deg WEST(W). With your position so far west and your target so far east im not surprised it wants to take you west. That does have me wondering whats up with the distance indicators....

Edit if I mistake not, both your position and target longitude are indicating EAST rather than WEST. Since E is positive and W is negative, your position longitude is > target longitude which means your target is west of you after all.

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 7:24 pm
by JonathanBleeker
In future, when you want to increase the NUMBERS on the counters for a negative hemisphere (South or West), scroll DOWN on the controls rather than UP.

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 8:16 pm
by WarHorse47
JonathanBleeker wrote:Edit if I mistake not, both your position and target longitude are indicating EAST rather than WEST. Since E is positive and W is negative, your position longitude is > target longitude which means your target is west of you after all.
You are right. My bad (or should I say Senior Moment).

I think I need stronger glasses or a bigger monitor. :mrgreen:

--WH

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 10:32 pm
by YoYo
WH, this tool is ok for this : positive East and negative West :) if You want to check it without FSX.

http://www.magnetic-declination.com

Re: INS / Navigation Computer tutorial (video)

Posted: Sun Jul 12, 2015 10:59 pm
by WarHorse47
YoYo wrote:WH, this tool is ok for this : positive East and negative West :) if You want to check it without FSX.

http://www.magnetic-declination.com
Interesting. Thanks.

Just finished researching sites to give me lat-long data for future flights. It's going to be a busy week.

--WH

Re: INS / Navigation Computer tutorial (video)

Posted: Mon Jul 13, 2015 7:00 am
by JonathanBleeker
WarHorse47 wrote: I think I need stronger glasses or a bigger monitor. :mrgreen:
--WH
Zoom :geek:

Re: INS / Navigation Computer tutorial (video)

Posted: Mon Jul 13, 2015 9:13 am
by gulredrel
A question concerning magnetic variance counter.

In the manual the plane seems to be parked at Edwards AFB, the manual shows 166° to set on the counter.
Local declination should there between 12° and 13°.

The video above also shows a value of 13° to dial in.

I'm a little confused, do I have to dial in the absolut value according to airplane current heading or declination value for current position?

Re: INS / Navigation Computer tutorial (video)

Posted: Mon Jul 13, 2015 9:17 am
by JonathanBleeker
The declination. The manual picture seems to be an error. When the declination is properly entered, the needle in the variation indicator just above the counters will be centered after alignment is complete