RVR and 1/4 mile?

[Kittyhawk1048]

Got a question for the forum:

If you have a flight taking off from lets say JFK and the ASOS is reporting 1/4 mile but it is not reporting RVR. When looking at the FAA website under the real time RVR it says all rwys are 6000 or better. Do you need a T/O alternate if the ASOS is not reporting RVR, but if the capt. radios the tower they tell him what the RVR is and it is better than 6000?

 

[homerjdispatch]

Is the aircraft CAT II or CAT III certified? If so, it doesnt matter.

 

[Kittyhawk1048]

No cat II or III

 

[ShutupandFly]

not requered on the release but would give him one anyways (good luck getting a Capt to take off without one). At least give the capt a pen and ink to a good altn with burns and wx. They won't need to get more fuel for it so no big deal.

 

[RJAA]

It does matter here

At my airline it does matter. Takeoff alternates are required whenever the existing conditions are below CAT I mins or applicaple higher landing mins regarless of CAT II or CAT III status. I think it's because we can't shoot CAT II or CAT III approach single engine, or it's highly undesirable to do so.

 

[DX Jake]

At my airline it does matter. Takeoff alternates are required whenever the existing conditions are below CAT I mins or applicaple higher landing mins regarless of CAT II or CAT III status. I think it's because we can't shoot CAT II or CAT III approach single engine, or it's highly undesirable to do so.

ditto for southwest. a t/o alternate is required when the weather is blo non-hgs cat 1 mins. it wouldn't hurt, it doesn't cost anything.

 

[DispaccioDaddyO]

To answer the question: No. As long as RVR is reported as above Cat I mins then the T/O Altn is not required. The RVR does not have to be reported in a METAR or ASOS to be used but simply "reported." Even for liability all ATC radio transmissions are recorded.

Hope this helps.

 

[propsarebest]

If the ASOS isnt reporting RVR, then it isnt existing, therefore RVR isn't controlling, so YES, you do need a TOA, because 1/4 is below CAT 1 landing mins.

 

[DispaccioDaddyO]

If the ASOS isnt reporting RVR, then it isnt existing, therefore RVR isn't controlling, so YES, you do need a TOA, because 1/4 is below CAT 1 landing mins.

Check out your AIM 7-1-16g:
Ten minute maximum and minimum RVR values for the designated RVR runway are reported in the body of the aviation weather report when the prevailing visibility is less than one mile and/or the RVR is 6,000 feet or less. ATCTs report RVR when the prevailing visibility is 1 mile or less and/or the RVR is 6,000 feet or less.

Therefore if the tower operator reports it then it DOES exist and the takeoff alternate is NOT required.

 

[ss9e]

If the ASOS isnt reporting RVR, then it isnt existing, therefore RVR isn't controlling, so YES, you do need a TOA, because 1/4 is below CAT 1 landing mins.

rvr is being reported by the tower, which makes it an official observation. takeoff alternate is not required because rvr is controlling.