Pros & Cons Of A Backbeam Approach

It's called a Backcourse approach(BC) in the US. You're correct, it doesn't have a GS. It's flown like a Localizer approach. The reason you would use one is in weather(wind) conditions that require a instrument approach but not in the direction of the normal ILS. It's more difficult than a ILS so pilots, given a choice, would rather not do this type of approach. If flown with a VOR/ILS indicator, you will receive reverse sensing. Using a HSI, with the front course of the ILS set, gives correct sensing. The BC also tend to be more sensitive because the Localizer antenna is located at the far end of the ILS runway. When you come in on the BC, you are closer to the antenna. Even though the signal is always there, you can't fly a BC approach unless one is certified for that airport. Many locations don't have BC approaches because it's not needed or terrain and or signal distortion prevent the certification.🙂

➡ http://www.naco.faa.gov/d-tpp/0611/00717LBC17.PDF

Also, they are rare to find, but Back Course Localiser courses sometimes exist with a glideslope, however, the majority don't.

😉

Gentlemen, thanks.

CRJCapt: I'm not sure why you think a back course approach is any more difficult than a localiser approach, True, a pilot executing a BC approach has to be able to walk and chew gum at the same time but any competent IFR pilot should have no difficulty at all with a BC.

As noted above, one disadvantage is that most BCA's produce reverse sensing on the VOR, HSI, etc. That should only be a problem for a pilot in his/her initial training stages. The other disadvantage, not noted above, is the minimum descent altittude for a BCA is normally higher than for an ILS. In marginal weather, that can sometimes make the difference in completing the approach or having to execute a miss approach and go to an alternate.

Having flown dozens, possibly hundreds of BCA's without the aid of an autopilot, I can assure you it is not a difficult approach to fly well. I'd much rather fly a BCA than an ADF approach, any day.