INS PI

I have returned to the TriStar (original version, not professional) and I know this topic has been discussed before and my apologies for the duplication but I've tried all the suggested solutions and still have the same problem EXCEPT that is when I load the turtorial flight from Brize Norton to Hannover. The INS on any other flight will not drop past 7. Why should that be? I assume the tutorial flight is using the same software. Yet try as I may, with the long and the shortcut method, re-starts, closing fsx, changing aircraft selection, changing the weather, reloading the fuel, talking to the passengers......is there a pilot onboard! I am at a complete and utter frustrated loss as to why this INS will not calibrate past 7. I know without the shortcut it will take at least 15 mins but I have give it a lot longer than that and with no success.  Could it be something to do with the way the waypoint coordinates are formatted when inputting the ramp position. I never really know what digits should be entered for Lat and Long especially when there are zeros involved and what to leave in and what to round up? Just as an example of a coordinate waypoint from Gatwick to Munchen E0020000!  Are there any new thoughts around which may throw some fresh light on the problem which as most of you know has been raised before ie the 'not getting past 7' scenario?  Cheers guys and gals and thanks for watching!

Hi Rob thanks for taking the time to respond. I've just tried again to align the INS with the same result. Here is the scenario; Positioned at Gate 112 Lester B Pearson (CYYZ) for a flight to Cincinatti (KCVG) using the RAF K1 Desert Storm model. Fuel on board, 20/40/20 per cent in tanks. Bring the battery on, power up the APU and avionics and ofcourse hand brake is on. Shift/Z to get my Gate position which for me is N43 40 98 W79 37 00. On the overhead, switch knob to Nav (fast alignment process), INS gauge is in the Pos position. I then enter the coordinates into the INS as per the manual. In the process the INSERT button is pressed twice ie once for each entry. Interestingly the illuminated INSERT button does not extinguish after the second press. Return to the overhead and switch the knob to Align. The INS gauge PI almost immediately drops from 9 to 7 and there it rests for ever more. One interesting factor is that the INS gauge battery light comes on briefly then extinguishes. (This scenario has been referred to by someone else in an earlier post in this Forum). There is no warning code on the LED. I did wonder whether the battery light had a bearing on the PI failing to drop further and whether a FSUIPC tweak to extend battery time would have an inluence but have not tried this yet. For interest my planned route was: CYYZ DCT ANCOL V443 FAILS V522 DJB J83 APE STAR KCVG. As far as I know the 'V' routing has no influence on INS and it comes down to waypoint coordinates and/or VOR DMEs when programming the INS. I have no other issues with the aircraft and it flies absolutely OK without programming the INS but using the standard GPS and/or radio NAV.  Any more thoughts? I have re-installed the aircraft since first experiencing the problem which made no difference. As I said before, the turorial flight works like a charm with the INS behaving as it should. If memory serves it even uses the RAF K1. Regards  Bill

tanka wrote: ....One interesting factor is that the INS gauge battery light comes on briefly then extinguishes. (This scenario has been referred to by someone else in an earlier post in this Forum)....

Bill - just remembered about that battery light 'issue' while aligning (from the manual published by simufly.com on the Delco Carousel INS):
It illuminates amber during alignment at API 8 for about 15 seconds indicating the battery test is in progress. It illuminates also when INS is operating on battery power.

Cheers!
Rob

Hi Bill,

OK, managed to get time to do the whole flight without interruption this evening.

Here's the results:

Flew Tristar RAF Desert Storm K.Mk1
Started with fuel 20/40/20 and default cargo/crew/passenger weights.
I used the startup procedure as laid down in the RAF Tristar tutorial flight.
I did a quick alignment, as per the tutorial.
Used real-world weather updates.

23:10 - entered cockpit
23:15 - started INS quick alignment
23:44 - engines on
00:07 - take-off (after 2 AI got stuck on the active!)
01:26 - landed
01:40 - full shutdown completed, exit flight.

Cruised at 32000ft, remaining fuel was 7.4/20.1/7.4
Logbook total time says 2.4hours.

Ramp position (gate 112) at CYYZ entered into INS as:
N43*41.0'/W79*37.0' (remembering to use INS DME wheel set to 0)

INS PI results (timed on a stopwatch, the minutes given are accurate give or take a sec or two):

95 - 0:00
85 - 3:28 (batt light on, off at 3:45)
75 - 6:25 (resets to 95 at 7:15)
95 - 7:15
85 - 10:45 (no batt light test)
75 - 13:56
65 - 15:58
55 - 17:15 (MSU green light on, 2D panel only)

At 55 PI I entered in the cords for the flight as follows (these were found using the FSX flight planner and checked against skyvector flight planning website). The cords here have had last digit dropped and rounded up as per the tutorial instructions:

ANCOL N43*12.7'/W80*01.2' on INS DME wheel 1
FAILS N41*50.5'/W81*25.3' on INS DME wheel 2
DJB   N41*21.6'/W82*09.8' on INS DME wheel 3
APE   N40*09.3'/W82*35.3' on INS DME wheel 4
KCVG N39*03.1'/W84*40.1' on INS DME wheel 5

I reverted to VOR NAV 90miles from KCVG by flying to FLM VOR 117.00, then heading on 314deg until intercepting the ILS for Rwy36R 004deg on 110.35 (not a true STAR, but good enough for this test flight).

I also performed a successful DME update using APE on 116.70, starting at 130 miles away.

So, apart from the quick align time not being so quick (plus the initial 75 PI reset to 95 PI) there were no issues to be found.
All the cords entered into the INS ok, no INSERT button staying lit problems.
No power/battery problems - electric power continuous from flight start to shutdown.
No autopilot over-control/loss of control problems, no rolling over while changing NAV or HDG values rapidly.

It's late again here so I'll be signing off for now, but if you think it'll help Bill, tomorrow I'll write out a step-by-step on what I'm pressing/clicking on the INS when I program it.....there is 'something' different in what we're doing somewhere along the way, if the above doesn't shed any light on things, maybe a step-by-step will.


Cheers Bill!

Rob

Hey Rob, I thought that the Lat was 5 digit and the lon was 6? So shouldnt your west lon read for example W080*01.2 not W80*01.2?

Cheers,
Nathan

Great story Bill, I had a look around it in Sydney Australia once too, was inside a 767 taxing when it took off and it was extreamly load still. Always wanted to fly it one way between London and New York and get the Queent Mary II the other way. Such a shame and loss to the aviation world.

Cheers, Nathan

Gentlemen!

Further to the discussion on the Tristar Delco Carousel INS included in the original release of the L-1011 by JustFlight:

As mentioned above, Latitude coordinates are 6 digit numbers, while Longitude coordinates are 7 digit numbers.
To clarify for others reading this thread, the coordinates are made up of 3 values written in order - degrees, minutes and seconds.
So, for example 51*47.10N is 51 degrees, 47 minutes and 10 seconds North.

The minutes are measured from 0 to 59 for any one degree,
The seconds go from 0 to 100 for any one minute of lat/lon.
Hence why on the JustFlight RAF Brize to Hannover tutorial flight, you will find cords such as N51*44.9/E001*36.7 - the last values of each coord has been rounded up, the North coord to 90 seconds, the East coord to 70 seconds.

When you enter coord data into the Tristar INS, the displays are initially zeroed:
00'00.0N or 00'00.0S
and
000'00.0E or 000'00.0W

If you find a coord with zeros in front (such as E001*36.7 for example) the zeros that are shown before the first digit with a value of 1 or more are 'dead' and do not need to be entered into the INS (this applies to N, S, E and W cords).
E001*36.7 would be entered as: 6(to select Easterly), then 1, 3, 6, 7, then INSERT.
The main thing to remember is that the degrees, minutes and seconds values end up in the correct 'data bracket' within the INS digital displays.
If a coord had a minute value with just a single digit, then we add a 'spacer' zero in front of it when it's entered into the INS. The zero in front does not alter the value of the minute - 05 for example is still the same value as 5.
For the seconds, if the value was from 00 to 05, we just input the value 0.

The seconds are limited to a single digit entry, which is why the final number is rounded up should the 'deleted' number have a value greater than 5.

Examples - if a coord were 001.01.41W, then we would press 4(to select Westerly) then 1, 0, 1, 4, INSERT.

If we had 001.01.46W, then we would knock off the end 6, and as it's greater than 5 we would round up the 4 to a value of 5 and in the INS press 4(to select Westerly) then 1, 0, 1, 5, INSERT.

If we had 001.01.98W then we would knock off the end 8, and as it's greater than 5 we would round up the 9 to a value of 0 and then round up the 01 of the minutes to 02 (001.02.0W). So in the INS press 4(to select Westerly) then 1, 0, 2, 0, INSERT.

Other things to remember:
When you're entering your start location on the ramp at any airfield (using the quick align method), make sure the Mode Selector on the INS is set to POS, the MSU knob is set to NAV and the DME wheel is rotated to '0' before you enter the coords in. Once that's done, then turn the MSU knob to ALIGN.
Don't enter any other waypoint coords into the INS until the Index Value has hit 5 or less.
When you're ready to enter waypoint coords, make sure the INS Mode Selector is set to WAY PT, the MSU knob is back to NAV, and that you remember to change the INS DME wheel to the next number for each new waypoint (1, 2, 3 etc).
The DME Update inflight works fine if you follow the procedure in the RAF tutorial. Remember to get an altitude level (rounded up or down to the nearest 1000ft) for any DME/VOR station on your route while doing the flight plan, as you need to factor the ground elevation of the transmitter into the data you enter when performing a DME Update.
The NAV1 must be used to tune into the DME/VOR you use to make the update from, and must be kept on until the update is completed (so be ready to use NAV2 and or the ADF for gathering additional nav data in the meantime).
Just like the tutorial, I find that starting a DME Update using a VOR/DME when it's just hitting 130nm away gives good results - this is while cruising at 32,000ft and 280kts on the autopilot.

I hope the above is of help and interest

How's things going with the Tristar and the INS Bill? Have you had chance to get any more flying time in on this one?

Cheers!
Rob