Cat 1 Rvr Limits.
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Cat 1 Rvr Limits.
According to EU-OPS I understand that during a Cat 2/3 app the mid point and stop end RVR figures can never be lower than the published Take off minima.On a Cat 1 app what governs the mid point and stop end figures? and are these figures always the same? Many Thanks.
Last edited by zuz; 4th December 2008 at 13:42.
Per Ardua ad Astraeus
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From: UK
In my ops manuals it says Touchdown RVR (550m) is the decider, and depending on which part of my OPs Manual I look at I either have to have at least 150mRVR (or 75m in another part???
) at the mid-point and 75m at the stop end - both of which (75m) are below the T/Off minima.
) at the mid-point and 75m at the stop end - both of which (75m) are below the T/Off minima.
) at the mid-point and 75m at the stop end
Per Ardua ad Astraeus
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From: UK
H8 - I agree with your figures: JAR (and now EU ops 1:405) say that.
To atttempt to answer Zuz's question (NB I HAVE ploughed through JAR/EU Ops but of course could have missed some sub-para!)
According to EU-OPS I understand that during a Cat 2/3 app the mid point and stop end RVR figures can never be lower than the published Take off minima.
I cannot see those words. In as much as the absolute minimum take-off RVR allowed is 75m and ditto the landing, I suppose semantically you are correct, although no reference I am aware of is ever made to 'Take-off' mins when determining landing mins.
On a Cat 1 app what governs the mid point and stop end figures?
Again, the book says:
"If reported and relevant, the mid point and stop end RVR are also controlling." with a note: "“Relevant”, in this context, means that part of the runway used during the high speed phase of the landing down to a speed of approximately 60 knots."
So, my interpretation is a 'normal' absolute minimum of 125m mid and 75m stopend - with the proviso that your operator may determine that stop (or even mid) are not 'relevant' - reduceable to 75m at each for certain a/c (IIIb).
and are these figures always the same? No
Anyone else got a different interpretation?
To atttempt to answer Zuz's question (NB I HAVE ploughed through JAR/EU Ops but of course could have missed some sub-para!)
According to EU-OPS I understand that during a Cat 2/3 app the mid point and stop end RVR figures can never be lower than the published Take off minima.
I cannot see those words. In as much as the absolute minimum take-off RVR allowed is 75m and ditto the landing, I suppose semantically you are correct, although no reference I am aware of is ever made to 'Take-off' mins when determining landing mins.
On a Cat 1 app what governs the mid point and stop end figures?
Again, the book says:
"If reported and relevant, the mid point and stop end RVR are also controlling." with a note: "“Relevant”, in this context, means that part of the runway used during the high speed phase of the landing down to a speed of approximately 60 knots."
So, my interpretation is a 'normal' absolute minimum of 125m mid and 75m stopend - with the proviso that your operator may determine that stop (or even mid) are not 'relevant' - reduceable to 75m at each for certain a/c (IIIb).
and are these figures always the same? No
Anyone else got a different interpretation?
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From: ? ? ?
According to EU-OPS I understand that during a Cat 2/3 app the mid point and stop end RVR figures can never be lower than the published Take off minima.
I cannot see those words.
I cannot see those words.
Quoting all the rest of BOAC post.
Last edited by Henry VIII; 18th December 2008 at 08:13. Reason: gram
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From: another place
Declared relevent distance is the distance in your ops manual for the aircraft take off or landing as appropriate.
If for instance on your aircraft the declared relevant distance is 900m for landing, then on a 3000m runway you can ignore any stop end RVR as it is not relevant.
Same sort of calc is used for take off but the relevant distance will be more.
D and F
If for instance on your aircraft the declared relevant distance is 900m for landing, then on a 3000m runway you can ignore any stop end RVR as it is not relevant.
Same sort of calc is used for take off but the relevant distance will be more.
D and F
