Hi guys,

studying for my IREX i was just wondering 1 thing that came to my mind. When your on the ILS and do a altimeter check at the OM is there an acceptable leeway on the altitude you must follow, i'm trying to say that if you do an alt check and your just say 10ft off what is given on the approach plate, does that mean you have to discontinue the ILS and do the LOC for 10ft. I haven't been able to find an answer to that in the AIP


Cheers,
Raphael

i didn't mean to put it under important news could you please move it to General Enquiries or IREX

Hi Raphael
AIP ENR1.5 para 7.3.1 states if there is an unexplained discrepancy at a fix on the glidepath where an altimeter check is take place, the approach is to be discontinued.
Meaning, if the needles are centred and altimeter is not showing the required check height, then this would be an unexplained discrepancy. What you do have to consider is the lag in the altimeter, the position of the needles and what the reading was when the marker beacon sound was at its strongest.

Grey area, I know.

10ft would probably be considered as lag. One dot high on the glideslope and reading 100ft high would be an explained discrepancy. Therefore the approach can continue. Needles centred and 50+ft out, different story.

It used to be if you were low with the needles centred, you flew to the DA. And if you were high, you add the difference to the DA. It least it was a definite figure to work with.

I know 'unexplained discrepancy' is a bit fuzzy.

Hope this helps a bit.

Cheers ,
Mister W

Just wanted to let you guys know i passed my IREX today 85% first go, anyone that is struggling with this subject i would recommend buying the bob's online practice tests they helped a lot, just want to say thanks for all the help during my CPL & IREX. and now time to start the ATPL's

Cheers,
Raphael

Way to go Raphael! Well done. What a great job you've done with the theory components. Good luck with the ATPL exams.
Cheers,
Rich