Originally Posted by
RudderTrimZero
"Maintain xxxx ft, cleared ILS XX approach". That, to 99.99% of pilots is totally unambiguous and keeps the airwaves quiet.
That saves about 4 syllables compared to “When established localiser XX, descend on the glide path.”
The ILS approach starts at 2500 and there is other IFR traffic at 3000 and VFR aircraft at 2400 and below. Clearing aircraft for the ILS approach at 4000’ in the past has led to some descending early to 2500.
If only 0.01% of pilots find it ambiguous, that’s about 2 incidents a month. (Although you might want to check my maths👍
I completely agree though, it does feel unsatisfactory to be at odds with most of the rest of the world but there is a strong safety case behind it.