Low visibility taxi and takeoff

[C77MD80]

Ok experts. In DTW the other day visibility was at 500/inop/500. The only operators able to go were AA and UAL. Most operators were waiting for 600 rvr. How come UAL and AA have 500 rvr but not others? If you look at the 10-9A for DTW it says 6/6/6. Isn't that controlling regardless of what's in your ops spec? Any UAL or AA guys (or those with an ops spec w/5/5/5 care to comment?
Most of us were stuck. There was a lack of comfort to go back to the gate since if you look at your 10-9f page (SMGS) the visibility for these taxi routes are RVR1200-RVR600. A good argument is that RVR is controlling for the runway and not the taxiways. Although I did hear someone say "we've got less than 300 feet visibility" while they were taxiing. So whose gonna taxi back to the gate (if you need to) and whose gonna stay put until RVR comes up?

 

[regionalcap]

You might try posting this on the majors section. You could get more responses there...just a thought. I always that your ops specs only allowed you to go lower as long as the chart was lower too. I didn't think you could ever go below what the chart says. Sounds like some fun times in DTW.

 

[ksu_aviator]

Ok experts. In DTW the other day visibility was at 500/inop/500. The only operators able to go were AA and UAL. Most operators were waiting for 600 rvr. How come UAL and AA have 500 rvr but not others? If you look at the 10-9A for DTW it says 6/6/6. Isn't that controlling regardless of what's in your ops spec? Any UAL or AA guys (or those with an ops spec w/5/5/5 care to comment?
Most of us were stuck. There was a lack of comfort to go back to the gate since if you look at your 10-9f page (SMGS) the visibility for these taxi routes are RVR1200-RVR600. A good argument is that RVR is controlling for the runway and not the taxiways. Although I did hear someone say "we've got less than 300 feet visibility" while they were taxiing. So whose gonna taxi back to the gate (if you need to) and whose gonna stay put until RVR comes up?

I'm not at AA or UAL, but I do know that ops specs can trump the -9. It all depends on the wording in the exemptions. Usually the exemption will allow for departures as low as 6,6,6 or 5,5,5 unless the airport has higher than standard miniums. So if the listed minimum is 600 and your ops spec goes to 500, you are good to 500. But if the airport is only good to 2 miles, than you are stuck with 2 miles.

 

[great cornholio]

I thought the ops specs trumped anything that jepp has out for that kind of stuff. I know when we have a alt airport we can derive our mins for that airport to make it legal for dispatch. We ignore all of the numbers that Jepp puts out for the "filing as alternate" table. Unless it says N/A then we can't use that approach. Its the same thing for us with the 6/6/6 takeoff we dont have to look at what the Jepps say we just need the requirements for what our ops specs say...centerline lights...centerline markings...2 working RVRs...etc.

 

[T206driver]

I am just going through my ATP books to take the exam. One of the test questions were that if you had only a 2 engine airplane then you needed 400 foot ceiling with an RVR of 6000 ft for departure. How does this all work? I guess Op Specs. trump everything.

 

[ksu_aviator]

I am just going through my ATP books to take the exam. One of the test questions were that if you had only a 2 engine airplane then you needed 400 foot ceiling with an RVR of 6000 ft for departure. How does this all work? I guess Op Specs. trump everything.

Ok....400 foot/RVR 6000 might be airport specific.

Ops specs only trump the things that they specifically list. That is why the original post is hard to answer correctly with out knowing the full ops specs. I just pointed out that most ops specs generally state that the carrier can use a lower than standard minimum for t/o unless the t/o mins are above standard. But that is just a generalization.

 

[Rally]

Its ops spec say a is'nt TO mins 1 sm? or 1/2 or so. If your ops specs state you can takeoff if the approach in use is above mins (1600 RVR etc). Also are some Jepps tailered to certain airlines?

 

[MATHEWS]

OPS Specs always trump the Jepps to echo what someone said earlier, end of story. I am gonna go out on a limb here and say all 121 carriers are not concerned with what the jepps have to say, they simply go off of what is in their manual. And some majors are indeed approved for a 5,5,5 take-off as was the case here I am sure.

FYI same thing goes for alternate minimums. You'll never see a 121 carrier concerned with alternate minimums listed on the back of the jepps unless there is a n/a in the box.

 

[bigsky]

standard part 121....
can take off with 1/4 mile or 1600 rvr(touchdown rvr is controlling) provided various lighting and ry markings or at least adequate visibility....etc

1200/1000 ...our ops specs say 1000/1000 if have ry centerline lights

600/600/600(500/500/500) all 3 rvr required( 1 may be inop) requires centerline lights and ry centerline markings visible

Our ops specs say 500 rvr.... in an airport like Seattle, the jepps say 300 than I am good to go. If the chart says 6/6/6, I believe you are limited by the airport restriction. Again I think this is due to airport has to have stop bars on ry below 600 rvr(smgcs)
I have heard it both ways from everyone from the FAA on down. Probably as long as there is no incident no one ever says anything, but God forbid something go wrong and I think this would be pinned on the crew.

My personal guess is some operators have 500 rvr in their op specs as this is alligns with the ICAO requirement of 150 meters.

 

[Deftone45075]

Newer versions of the OpsSpecs - C079 indicate 500 RVR(5/5/5)

There are two different ops specs for visibility below Standard:

C057 (I believe, don't quote me on the number) Allows T/O to be conducted provided visibilty is equal or greater than the lowest applicable Category I Landing Minimum. This authorization DOES require the information on the 10-9 to agree.

C079 allows T/O in conditions less than Category I Landing minimums (i.e. 1/4 sm or 1600 RVR, 1000/1000 RVR and 500/500/500 RVR). Due to the wording of C079, no reference is required to the 10-9. If all required visibilty and equipment restrictions are met, the minimums published in the operators OpsSpecs may be used.

We have had 500 RVR in our OpsSpecs for a couple years. It is interesting, when reading the fine print, that 500 RVR can apply to runways served by only two transmissometers.