False localiser situation
 

hi

.. which is why one uses something else to establish the fact of being on course prior to following the needle.

Years ago, I was doing some contract training work for SAA on the B732 and the sim presented a textbook false localiser for (if I recall correctly) Cape Town. It was easy to set the scene for the problem if crews were other than disciplined in their descent navigation - especially if the automatics were set for capture too early - confused a few chaps over the period - but only once on the basis of once bitten, twice shy.

Plenty of articles such as this one on the net - https://flightsafety.org/asw-article...alizer-signal/

False courses exist on nearly all Localisers due to the design. Theyre normally around 35 degrees either side of the LLZ track. Same issue with Glide Path aswell (on a 9 degree profile normally). Alot easier to avoid these days with GNSS, however holding the same track whilst holding a really inappropriate heading should set off alarm bells.

It happens.

Eckhard

MEX 05 - exactly right. A place that is tough enough with the turn to final from the north east in a 'heavy' given the density altitude and approach speeds in a B747-400!

It's difficult enough intercepting the correct LOC with the radius of turn, without having to deal with a false LOC capture - nightmare - made even worse by it being after a 10 hour flight at about 0200 on the body clock.