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Guest lbb

DIRECT navaid and Jeppessen RNAV procedures

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Hi guys,Two related questons.Some days ago the authors of the EHAM SIDs and STARs noted that the use of the DIRECT command would cause problems, as in the following exampleSID LEKKO1S RNW 24 NAVAID OVERFLY EH001 DIRECT NAVAID EH039 NAVAID LEKKO 6000where after passing EH001 the route line would disappear from the ND.Has there been any news on this?I checked it out for myself and indeed when I simply leave out the word DIRECT there is no problem. On stuydying the relevant Jeppessen chart I noticed that their RNAV procedure reads like thisTHR24 - EH001 - EH039 - Lekko Int.What exactly is the meaning of this information? Is it for the pilot to check that his FMC gives the same procedure? Or is this what the pilot would put in the FMC when there is no procedure? But then what about the distinctions between fly by and fly over? If you read the procedure as it is written out, it does look like you have to overfly the EH001 waypoint before turning, so does that mean that EH001 is "pre-defined" so to speak in the FMC to be fly-over and EH039 is not? You can't tell from simply looking at the RNAV procedure, so how would the pilot know?Questions, questions, questions :-) I guess you could say this sim is thought-provoking!Leo Bakker

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Leo,On My Jepp Charts for Amsterdam,EH001 is defined as a circle with a 4 point star in the centre.The other RNAV Waypoints are defined as a 4 point Star.it seems that the circle is used to define a fly over waypoint in the charts. Flyover and Flyby would be hard coded into the Sim.With no procedure in the FMC, the pilot would fall back to the following:track 240 degrees until SPL @ 4 dme.intercept 154 bearing towards NV NDB.intercept 180 radial from SPL vor to LEKKO.This could be set up in say the FIX page, with SPL and NV as the 2 fixes. a 4DME Range ARC drawn from the SPL VOR. The 180 Radial entered. For NV you would enter the reciprocal of 154 (334) to get the Bearing displayed.You would then set the Radios etc up to display the RAW Data needed for the procedure.HTH

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Ok,But with no procedure in the FMC you can enter the RNAV waypoints in the FMC to build up the procedure (if they are mentioned in the latest navdata that is), that's why they called RNAV fixes.The only drawback of this is the earlyturn to EH039 before EH001 is reached...Erm... that's how I think it is :()Greetz,Marc Nieuwhof

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