This is one of those “when-did-you-stop-beating-your-dog” kind of questions. There isn’t really any way to answer it without getting into trouble of some kind.
I am of the opinion that flight training is more than just practicing the manipulation of the flight controls. Of course, low visibility approach training surely IS to practice those flight control manipulations (particularly for CAT II and CAT III situations) – because as we all know, it might be some time between the requirements to do it “for real.” However, the piece that often gets lost is the piece of practicing the ability to see and recognize the cues a pilot must use to provide him or her the information needed to verify where the airplane really “is” on the approach, where it is “going” at any given time on the approach, and to practice the reactions to whatever is seen that leads to the appropriate flight control input (pitch, bank, yaw, power, trim) to safely continue the descent to the runway and land.
As you would probably guess, the traditional way to “simulate” a lower visibility when flying the airplane is an “all-or-nothing” approach (no pun intended). You use some vision restricting device; i.e., a hood or some sort of screen placed on the glare shield in front of the forward window. These methods produce very realistic “zero visibility” (meaning, you can’t see any farther than the hood or screen) until you remove that restriction, where upon you instantly have the visibility provided by mother nature. Of course in a “real” low visibility situation, “breaking out” doesn’t mean getting 12 miles and sunshine.
The aspect of this that I (personally) find a bit awkward is this is perfectly acceptable to the regulators in the US. While the advisory circulars describing the requirements for ground-based and airborne equipment as well as the operational requirements and training necessities, constantly use terms like “preferably in a simulator,” “typically in a simulator,” and “flight training should be accomplished in an appropriately qualified flight simulator,” there is no requirement to do so. Practicing in an airplane is OK.
My hearburn with this is that doing this practice in an airplane is really only ensuring the tick in the correct box. It simply cannot provide the training exposure that can be achieved in a properly qualified flight simulator. In today’s market, it would seem to me that the best method available for training what is actually going to be seen, felt, heard, etc., should be required – and we shouldn’t be accommodating that training using some cobbled-together work-around to fill the square … particularly when almost everyone recognizes the work-around done in the airplane as failing to provide what it really needs to provide!
Sorry, but you asked.