Minimums?

Airbus wrote in
:

In article
,
says...


Opps, sent a blank message.

Someone may have already pointed this out, if so, sorry for the
duplication, Brian, if one is flying a precision instrument approach,
like an ILS, that has a glideslope, when one arrives at 'minimums' the
runway environement must be is sight if the landing is to be
continued. It would not be uncommon for ILS minimum altitude to be
200 feet above ground, so there aren't too many seconds left to decend
that last 200 feet. See the runway or fly the missed approach.


There are other kinds of approaches, called non precision approaches.
These take you you to the vicinity of the airport for circling
approaches, or near the approach end of the runway, but do not give
altitude information. What happens with these is the airplane passes
over a final approach fix, which is some form of radio derived point,
and then the approach documentation permits the airplane to decend to
a fixed altitude. At that point it will have reached minimiums, but
the pilot in general will depend on a clock and airspeed estimates to
tell when (s)he should be over the airport. (S)he does NOT have fly
the missed approach when the airplane reaches the minimum altitude
permitted by the approach, but when the estimated position is close to
the airport. Think of a small airport in a flat region near the coast.
If the approach is from the water siide it might be reasonable for the
airplane to go down to 500 feet two NM from the airport, then continue
flying toward it for another minute (if speed over the bottom is120
kts), before flying the miss.

Sorry if this is all redundant.


Not necessarily redundant, but somewhat incorrect.
No obligation that the MDA and the MAP be close to each other, as you
suggest. Some pilots do try to descend progressively to arrive at the
MDA at or near the MAP, but others "dive and drive" losing altitude
first, then driving forward to the MAP. At the MAP, if one of the
visual items on the list is not in continuous view, (s)he MUST
initiate the missed approach. The missed approach may be initiated in
advance by climbing straight ahead, but no turns may be initiated
until reaching the MAP.




Yes, but not everywhere. The Brits regard MDA as a decision altitude.
They also don't allow a dive and drive type approach.

Bertie