What is different between DH and MDA and DA?!
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The question may come from a student pilot or PPL,
1)DA decision altitude- the altitude on an ILS approach at which if you do not have the required visual reference to land, you go around.
2)DH decision height- the same as above except with the altimeter set to read height above threshold (QFE) or from a radio altimeter if using this(eg CAT2 or CAT3 approach)
3) MDA minimum descent altitude- the minimum altitude you fly down to on a non precision approach at which (without visual reference) you either go around or maintain till missed approach point or final descent point depending on SOPs.
Just to add confusion, some non precision approaches now publish DAs which can be used if flying a constant descent approach.Also, If you fly a bus, the MDA box is used to set DH if using a barometric minimum.
1)DA decision altitude- the altitude on an ILS approach at which if you do not have the required visual reference to land, you go around.
2)DH decision height- the same as above except with the altimeter set to read height above threshold (QFE) or from a radio altimeter if using this(eg CAT2 or CAT3 approach)
3) MDA minimum descent altitude- the minimum altitude you fly down to on a non precision approach at which (without visual reference) you either go around or maintain till missed approach point or final descent point depending on SOPs.
Just to add confusion, some non precision approaches now publish DAs which can be used if flying a constant descent approach.Also, If you fly a bus, the MDA box is used to set DH if using a barometric minimum.
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that was great answer !thank you so much FatFlyer
i was wondering why pilot of airbuses always use MDA filed PREF page on ILS CAT2/3 instead DA!
and
for info of who are worry about my aviation situation!i m probationary first officer at IRAN and i knew enough about DA DH MDA and more...but its my habit to asking, always ,include which i known already because there is always something exist if u want for every thing
i was wondering why pilot of airbuses always use MDA filed PREF page on ILS CAT2/3 instead DA!
and
for info of who are worry about my aviation situation!i m probationary first officer at IRAN and i knew enough about DA DH MDA and more...but its my habit to asking, always ,include which i known already because there is always something exist if u want for every thing
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i was wondering why pilot of airbuses always use MDA filed PREF page on ILS CAT2/3 instead DA!
you set the baro minima (eg. npa or ILS CAT I) in the MDA box (or BARO box depending on software versions). You set the RA minima in the DH box (eg. CAT II / III app). That's it, no big deals.
Cheers.
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hawker750
Apart from being rude, you're wrong. It would have taken you less time to answer the question, if able. And, as it happens, Farid is a pilot.
From Tech Log Moderator - (a) anyone with an interest in aviation can ask any technical question .. and we intend "technical" to be interpreted fairly generally. Questions need not be about the flying side of things .. but will be welcome so long as they have at least a tenuous connection with aviation. Questions are asked and comments/answers provided by the most experienced through to the least experienced within the Industry according to their knowledge and interest in the subject.
Oh dear, I hope he is not a pilot, but there again I thought this was a forum for pilots
From Tech Log Moderator - (a) anyone with an interest in aviation can ask any technical question .. and we intend "technical" to be interpreted fairly generally. Questions need not be about the flying side of things .. but will be welcome so long as they have at least a tenuous connection with aviation. Questions are asked and comments/answers provided by the most experienced through to the least experienced within the Industry according to their knowledge and interest in the subject.
