ontheair Posted June 15, 2011 Share Posted June 15, 2011 My question is not EFB related, it's just to satisfy my "curiosité". I'm currently practising some published Loc/dme BC (back course) approaches : 304° 111.7 ITUS LOC (BACK CRS) FRONT CRS 124° at Tucson/KTUS is one of them I just found with others of the same kind by googling "Loc dme BC" As they are no longer allowed in France (what about Europe ?) except for only 2 Loc outbound departures at Chambery/LFLB (DANB2C/rwy 36) and Annecy/LFLP (DAN2B/rwy 22) I'm wondering if such approaches are common in the US despite they are considered rather dangerous : to fly such approaches the HSI needle must be directional wich means the HSI course must be set to the normal ILS front course while flying back course... Isn't it confusing ? 4 people (all of them PPL qualified + IFR rating for the captain ) died in a crah-plane just because the HSI needle was set the wrong way (non directional). The plane was flying the DANB2C SID at LFLB ... Think about it next time you fly (virtual or real) a Loc dme BC inbound or outbound... Link to comment Share on other sites More sharing options...
bradrcfii Posted July 17, 2011 Share Posted July 17, 2011 They are common in the US and not considered dangerous. Yes, set your HSI properly, part of the standard approach checklist. What I find interesting about the backcourse is that the CDI is much more sensitive since the localizer antenna is located at the approach end of the runway in case of the backcourse. Normally, the beamwidth is set at the threshold to about 400 feet (if I recall accuraltly). So in the case of a backcourse, the beam width is 400 feet at about the runwway length from the approach end of the runway so maybe 1.2 mile final or so. You might think a more sensitve cdi might be safer. As for the crash, I am sure the cause was much more involved that a backwards CDI. Link to comment Share on other sites More sharing options...
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