weather minima
Thread Starter
Join Date: Feb 2010
Location: minneapolis
Posts: 27
Likes: 0
Received 0 Likes
on
0 Posts
weather minima
on a recent line check a discussion came up if one can start an approach if lets saywith a reported ceiling of 200' ( DA(H) 300') and a visibility of 5000 m.As i have always thought visibility as being the controlling factor for an approach
Guest
Join Date: Apr 2009
Location: On the Beach
Posts: 3,336
Likes: 0
Received 0 Likes
on
0 Posts
on a recent line check a discussion came up if one can start an approach if lets saywith a reported ceiling of 200' ( DA(H) 300') and a visibility of 5000 m.As i have always thought visibility as being the controlling factor for an approach
Join Date: May 2002
Location: Permanently lost
Posts: 1,785
Likes: 0
Received 0 Likes
on
0 Posts
There is a clip on YouTube of a 738 doing an ILS into Venice. They are aware before commencing the ILS that the weather has been fluctuating around the minima. During the descent they are informed that the weather is below the minima and they commence a missed approach.
I queried whether they should have continued the approach to the DA and then, if not visual, commenced the missed approach. I was informed that the particular company's SOP was that once they were informed that the weather was below minima after commencing an approach that the crew was to conduct a missed approach.
I queried whether they should have continued the approach to the DA and then, if not visual, commenced the missed approach. I was informed that the particular company's SOP was that once they were informed that the weather was below minima after commencing an approach that the crew was to conduct a missed approach.
Join Date: Oct 2007
Location: fort sheridan, il
Posts: 1,656
Likes: 0
Received 0 Likes
on
0 Posts
it this simple...if you have the visibility you may start the approach....if you are below the minimum gs intercept altitude and the wx changes you can still continue to DA/DH
can even land ifyou see everything
now you and your company may have another idea if the apch says: ceilinou need the ceiling to be at or above published mins
can even land ifyou see everything
now you and your company may have another idea if the apch says: ceilinou need the ceiling to be at or above published mins
Join Date: Aug 2005
Location: fl
Posts: 2,525
Likes: 0
Received 0 Likes
on
0 Posts
Yes, that is the way it has always been in the US. Visibility for 121 or 135 operations, no ceiling requirement. At DH or MDA if you don't see the runway go around. I have done it dozens of times in 23,000 hrs.
Join Date: Aug 2005
Location: fl
Posts: 2,525
Likes: 0
Received 0 Likes
on
0 Posts
SSR, are you sure you have to be below the intercept altitude? I never knew that or was taught that. All I know is if you are outside the final approach fix and vis goes down you can't continue the approach. Inside you can continue to DH or MDA.
Join Date: Oct 2007
Location: fort sheridan, il
Posts: 1,656
Likes: 0
Received 0 Likes
on
0 Posts
bubbers
for all practical purposes the FAF, OM or LOWEST GS INTERCEPT altitude on an ILS e all the same point.
If you look at a profile view on a jepp ILS plate, the lowest GS intercept altitud eis so near the OM as to be the same.
LOWEST GS intercept altitude comes into play only in certain places when OM is ots
for all practical purposes the FAF, OM or LOWEST GS INTERCEPT altitude on an ILS e all the same point.
If you look at a profile view on a jepp ILS plate, the lowest GS intercept altitud eis so near the OM as to be the same.
LOWEST GS intercept altitude comes into play only in certain places when OM is ots
In the UK
You can commence the approach to the outer marker (4DME or equivalent, EASA its 1000ft) even if the RVR is below that required for the approach. If at this point the RVR is still below minimums you must Go Around. If you have passed this point you may continue to your DA/DH.
Join Date: Oct 2007
Location: fort sheridan, il
Posts: 1,656
Likes: 0
Received 0 Likes
on
0 Posts
just FYI...there is no final approach fix on the ILS approach. if you see the FAF symbol (maltese cross) it is for the localizer only approach. The lowest published GS intercept altitude is the FAF equiv.
if you look at a Cat 2 ILS you will see no maltexe cross at the marker.
if you look at a Cat 2 ILS you will see no maltexe cross at the marker.
Guest
Join Date: Apr 2009
Location: On the Beach
Posts: 3,336
Likes: 0
Received 0 Likes
on
0 Posts
bubbers44:
Not always for us OFs. I started in the 121 business in January, 1964. Ceiling was required in the U.S. until TERPs concepts came into being in November, 1967.
Yes, that is the way it has always been in the US. Visibility for 121 or 135 operations, no ceiling requirement. At DH or MDA if you don't see the runway go around. I have done it dozens of times in 23,000 hrs.
Join Date: Oct 2007
Location: fort sheridan, il
Posts: 1,656
Likes: 0
Received 0 Likes
on
0 Posts
I too remember when the changeover happened to just VISIBILITY for US approaches. I seem to recall when FLYING magazine came out with an article on the subject...prehistoric times...real paper magazine.
Join Date: Dec 2007
Location: paradise
Posts: 559
Likes: 0
Received 0 Likes
on
0 Posts
Approach ban is applicable to any approach precision or non precision. It's for a reason there! Approach ban differs from country to country so does the minima requirement. 
Guest
Join Date: Apr 2009
Location: On the Beach
Posts: 3,336
Likes: 0
Received 0 Likes
on
0 Posts
9.g:
Indeed, just as many countries still require both a reported ceiling of not less than the height above airport of the MDA or DA and visibility not less than that specified in the procedure. "Celing Required" above the minimums, at least on Jeppesen charts for those airports and/or countries.
Approach ban is applicable to any approach precision or non precision. It's for a reason there! Approach ban differs from country to country so does the minima requirement. 
