DME Arc - How?

[Guest malcolmt]

HiHow do you program a DME Arc into the FMC please?ThanksMalcolm

[Guest meyomyx]

No elegant way MalcolmBUTYou can do it by programming a series of colocated fixes at the appropriate distance from the navaid. You need to experiment with the spacing - you need fewer than you think for a 737. In fact, if you put too many in, the FMC cannot smooth the curve rapidly enough so if you're slightly out, the error gets magnified so by the third or fourth fix in the chain, it can start flying back on itself to overfly the fixes it missed!If you have enough enroute time, it's OK to do on the fly.A good example would be the Queenstown NZ VOR/DME Bravo approach. You only need about 3 colocated fixes. (Interesting and fun approach too! Especially if you have the NZ mesh). Then you can fly back to the ILS/LLZ/DME arc approaches at Wellington.If you want to see some more complex DME arcs, download my procedure file for Tribhuvan (Kathmandu) VNKT from Navdata and have a look. I've been there - it's every bit as fun as in FS9 - only your palms sweat more :)

[Guest Ray51]

Use the fix button to set a fix with the radius need. The FMC will not fly the arc but the dotted green line will give a a path to follow.

[Guest CS-THV]

With no FMC, the DME arcs are performed checking the distance to the station each 10 degress...So, with an FMC, what you do is (as a real pilot told me) this:1. Insert fixes each 10 degrees at the sames distance from the VOR/DME.Imagine you want to make a DME arc from FTM VOR (in Portugal) of about 100 degrees (from radial 100 to 200), at a distance of 15 miles.Insert the first fix like this:FTM100/15The second one, more 10 degrees as I told you:FTM110/15etc. etcuntill the last fix:FTM200/15And there you have a DME ARC. This arc was made to be performed from radial 100 to 200. If you want to do it around, start by the fix FTM200/15.