-FZDR
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-FZDR
Today I overheard on the radio an aircraft that requested holding instead of initiating approach due light freezing drizzle. After a while ATC informed them that there were no more FZDR and they were then ready for approach.
This is the first time I have heard anything like this and other aircraft were landing normally during this time.
Does anybody know if it is type related or a company procedure? It was Luxair, dont know the type...
SB
This is the first time I have heard anything like this and other aircraft were landing normally during this time.
Does anybody know if it is type related or a company procedure? It was Luxair, dont know the type...
SB
Join Date: Aug 2002
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It is wide agreement on the fact that freezing precipitation is very dangerous to any aircraft type.
How it is handled is depending on the type and the operator. Most airlines I know allow flying into light freezing drizzle and fog. It goes into good airmanship and experience how far you want to apply that. But it is wise to be careful.
When ATC reports that FZDZ is over, the crew was happy and continued the approach. Makes sense.
I see a minus in front of your FZDR title in your thread, so I might assume that it was light?
hth,
Dani
How it is handled is depending on the type and the operator. Most airlines I know allow flying into light freezing drizzle and fog. It goes into good airmanship and experience how far you want to apply that. But it is wise to be careful.
When ATC reports that FZDZ is over, the crew was happy and continued the approach. Makes sense.
I see a minus in front of your FZDR title in your thread, so I might assume that it was light?
hth,
Dani
Join Date: Dec 2005
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The fact is that no aircraft is certified to fly into FZDZ or FZRA, being it light or moderate or severe. During certification, the aircraft is certified to fly through freezing precipitation up to a droplet size of 50 microns. FZDZ starts at 200 microns and FZRA 500 microns. Those 2 conditions are known to be associated to SLD (supercooled large droplets), which will freeze immediately after coming into contact with the aircraft.
The term light or moderate has nothing to do with the droplet size but with the number of drops...and that's what a lot of pilots forget.
As well, it is also not always related to the outside air temperature. Talking about freezing precipitations, we are talking about the droplet temperature, which in those cases would be below 0 degres. So sometimes you can get freezing precipitations with temperatures being even slightly above 0 degres.
The term light or moderate has nothing to do with the droplet size but with the number of drops...and that's what a lot of pilots forget.
As well, it is also not always related to the outside air temperature. Talking about freezing precipitations, we are talking about the droplet temperature, which in those cases would be below 0 degres. So sometimes you can get freezing precipitations with temperatures being even slightly above 0 degres.
It was most probably a Luxair Emb145; where it explicitly says in the OM-B operation in said weather is prohibited. In the Boeing manuals in normally is not that explicit; only "not recommended" or "should be avoided" wording.
So yes, if your manual says it is prohibited and the ATIS mentions Wx like this what would you do?
So yes, if your manual says it is prohibited and the ATIS mentions Wx like this what would you do?
