controlling obstacle

controlling obstacle

[kən′trōl·iŋ ′äb·sti·kəl]
(navigation)
In terminal instrument procedures, the highest obstacle relative to a prescribed plane within a specified area; in precision approach procedures where obstacles penetrate the approach surface, the controlling obstacle is the one which results in the requirements for the highest decision height.
Mentioned in ?
References in periodicals archive ?
It was tall and well-lit, and in my avionics' obstruction database, but it also was the controlling obstacle for the 2700-foot minimum vectoring altitude to the north of my destination, the direction from which I was arriving.
The procedure has a visual climb over airport (VCOA) to mitigate the non-standard climb gradient when the controlling obstacle is more than 3nm from the departure end of runway.
It's a controlling obstacle for my descent when arriving from that direction, and local ATC usually won't clear me any lower than 2700 feet until I'm past it.
This means the missed should be charted way back by WIMET, which makes much more sense since the controlling obstacle could be the 328-foot tower just inside WIMET.
In other words, if flying at the MEF value, you could be only 301 feet above the controlling obstacle.