Posts about: "INS (Inertial Navigation System)" [Posts: 43 Pages: 3]

wiggy
7th Jan 2016, 19:15
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Post: 1918
Quote:
How exactly would you get the INS into memory mode so you could input the two digit code to activate the route section.
Just an observation and not my aisle but looking at flight deck images the INS display and keyboard looks like those I last witnessed on some older 747 classics in the very late 80s...in that case the "memory mode" was a page or pages on the flight plan containing lots of Lat/longs...
tomahawk_pa38
11th Jan 2016, 13:33
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Post: 1925
Thanks for the information guys - very helpful. Were the INS co-ordinates fixed or did they vary flight by flight please?
Bellerophon
11th Jan 2016, 23:25
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Post: 1926
FraserConcordeFan

... How exactly would you get the INS into memory mode so you could input the two digit code to activate the route section...

Concorde did have a facility to input a flight plan route segment into the INS and this facility was used on most flights. To explain this very briefly , let\x92s take a typical LHR-JFK flight as an example:

\x95 Press the amber REMOTE button on each INS CDU
\x95 Load the first waypoint (#1), usually Woodley, manually into an INS
\x95 Key WAYPOINT CHANGE and enter and insert \x930 to 1\x94 on each CDU.
\x95 Select DSTRK/STS and HOLD
\x95 Key WAYPOINT CHANGE
\x95 Key the DME catalogue number (from the flight log, usually 90 on a LHR-JFK sector) and insert
\x95 Key WAYPOINT CHANGE
\x95 Key the Route Segment number (from the flight log, usually 10 on a LHR-JFK sector) and insert
\x95 Cancel HOLD

Then the usual checking routine of:

\x95 Checking the lats and longs of the loaded waypoint lats with those given on the flight log
\x95 Checking the INS distances between waypoints with those given on the flight log
\x95 Checking the lats, longs and frequencies of the DMEs against the database guide

Return the displays back to WAYPOINT, cancel REMOTE, select AUTO and check the INS alignment.

Remember, with only nine waypoints available in the INS, this procedure would have to be repeated in flight, sometimes more than once. Takes much longer to write about than it did to do!


tomahawk pa38

... I'm just curious about what eastbound routings were into Heathrow...

The usual Eastbound routing on a JFK-LHR flight would be via track SN to 15\xb0W then on SL3 to BARIX to MATIM to PITEM to NIGIT and then OCK.


... and where the decel point was....

Let me just check we are talking about the same thing! The Decel Point was the point at the end of the cruise/climb, where we first throttled back and started to decelerate from M2.00 and then descend from, say, around FL 560.

The decel point was calculated in order that we would be just under M1.00 at the designated Speed Control Point , and so the Decel Point was obviously further back than the Speed Control Point.

The usual route was up the Bristol Channel, a bit to the South of our outbound route, crossing the Devon coast just to the North of Barnstaple, routing to a waypoint called MATIM, which is around 51\xb0N 004\xb0W.

In winter, on a JFK-LHR flight via SL3, the Speed Control Point was 110nm before MATIM , and we were required to be subsonic at this point. Typically, we would be just under M1.00, and around FL410, when we crossed the speed control point, having started down from FL 560 around 105nm earlier.

The decel point was of no real relevance to those living on and around the coast of Devon and Somerset, but the Speed Control Point was. The position and time at which we decelerated through M1.00 and became subsonic were always recorded on the flight log, along with the altitude and spot wind, in case of any future claims of boom damage due to a misjudged decel.

Best Regards to all

Bellerophon

Dedicated to the memory of Andr\xe9 \xc9douard Turcat (1921 -2016)