RVR Question..Go or No Go?

[PCL_128]

How about call or ACARS your dispatcher?

I know that I know the OpSpecs, and our GOM, especially when it comes to takeoff mins, very well...

Most DX should...

That's all well and good, but I'm not going to solely count on the DX to make the decision. The Captain needs to know that stuff on his own.

 

[great cornholio]

At my airline if what the first guy said happened then I could still go. Touchdown is the controlling RVR for T/O and Landing. However if touchdown is INOP then we can sub the Mid RVR. On a 6/6/6 T/O I need at least 2 of the RVRs to be working AND above 600. SO INOP/600/600 = Legal. INOP/500/600 = Not legal. 600/500/600 = Not legal. Pay rampie 5 bucks to run the midfeild RVR over with a tug and now you get 600/INOP/600 and you are legal again. We also need certain things like runway CL lights, edge lights and the runway markings (so a snow covered runway is a no go unless its nice and plowed). If only 1 runway has RVR and the wind will let you then take another runway and make sure the tower has the vis down as 1/4 sm. Now I can take off with just addiquate visual references IE runway edge lights, markings, or anything that I think lets me see what is runway and what is not runway. Was told someone tried to say that the windsock counted, but apparnetly the feds didn't like that one so much.

 

[bafanguy]

That's all well and good, but I'm not going to solely count on the DX to make the decision. The Captain needs to know that stuff on his own.

PCL,

You beat me to it, so I'll just second what you said. After reading this I can only ask whether the respective airline training departments are teaching this or not. If not, they should be. In my experience, these hair-splitting legal calls were rare but that just makes the need for understanding all the more important because one doesn't deal with it every day.

These legalities can get fairly involved and are probably not something one should attempt to grasp by innnuendo, supposition, or half truth. An expert needs to explain it all so the crewmembers are comfortable making this decision to go/not go.

Just because Brand X chose to take off ahead of you doesn't mean you can/should. The feds will know what one should have done...

One could do the "when in doubt...don't" thing, but this sacrifices a degree of efficiency one could have had if the legal parameters were firmly in mind.

 

[ksu_aviator]

Just for future reference, it is listed in the ops specs. All three companies I've worked for (121 and 135) it is in section C. I think it is usually CO75 and CO57 that discuss take off mins.

 

[Dave Benjamin]

BTW, enlighten me on how you can takeoff 1600/0/0. I don't know if you're 91 or 135 or 121, makes a difference. For me, if all three work we couldn't go in that case. Plus I've never seen that much variance in the RVR units, a few hundred feet difference is as much as I've seen.

I work for a 121 operator.

Your interpretation is common but incorrect. When I taught recurrent we used hypothetical but unlikely situations like the 1600/0/0 example to illustrate a point. Our Ops specs state that if we have 1600 TDZ RVR and adequate visual reference we're legal to depart. I emphasize legal to depart, not necessarily smart or prudent. Most Ops Specs have 3 different criterias for TO minima. You are not obligated to follow the most restrictive. The first paragraph in my Ops Specs states 1600 TDZ (mid if TDZ inop) combined with adequate visual reference makes us legal to depart. There is nothing stating that all 3 must be considered. However if it was 1500/0/0 we'd be stuck waiting.

The way I taught TO minima was to start with the least restrictive and then work down the list. Here's a flow chart of sorts.

Do I have 1600 TDZ (mid if TDZ inop) combined with adequate visual reference? If yes - depart. If no - consider next criteria:

Do I have 1000TDZ (mid if TDZ inop) and 1000 Rollout combined with operative centerline lighting? If yes - depart. If no - consider next criteria:
(NOTE: We used to have 1200/1000 now it's 1000/1000)

Do I have 600/600/600 (OK if one is inop) combined with centerline lights and serviceable runway centerline markings? If yes depart. If no - go take a coffee break.

I realize some may not agree and that's fine. I taught TO minima in this fashion with our FAA POI in the room. I had a very senior captain who disagreed with the way I was teaching. He called our Director of Flight Standards and later apologized to me. AFAIK, this is the proper way to apply TO minima. You are not obligated to use all 3 sensors if the 1600 and adequate visual requirement is met.

Just keep in mind that we're talking legality not airmanship. If I had a situation where it really was 1600/0/0 I would probably not depart. Your mileage may vary. See your local training department for restrictions and warranty information.

 

[PCL_128]

Dave Benjamin, I can't really say that you're wrong, but it's different than the two airline's I've worked for taught it. I've always been taught that you can still go if the other RVRs aren't being reported (ie they're inop), but if they're being reported, then you have to use them. I'm not sure the regs or Op-Specs really make it clear enough to figure out which way is correct. I'll have to do some more research. With winter approaching, it might actually become necessary to know pretty soon.

 

[Dave Benjamin]

PCL,

I've always liked your avatar.

Like any other airline our recurrent training program had to receive a blessing from the FAA. Your Director of Flight Standards may want to chat with the POI. You might be using a more conservative method than necessary. Ultimately it's up to us as captains to decide if it's both legal and safe.

 

[sweptback]

Jepp plates are not tailored to individual airlines. The only thing tailored to your airline would be info pages like 10-7 pages that show information specific to your airline. The 10-9 page is generic and shows the lowest applicable RVR (or visibility) that the runway allows. Your airline may or may not allow what the plate says. It's all up to what is in your Op-Specs.

Jepp charts are absolutely taliored to airlines, if they order them that way and pay extra for the service. Even then not every single chart is tailored, just the ones that are chosen to be. I've never seen a tailored 10-9 page, but that doesn't mean they don't exist. I have seen tailored approach plates, as well as tailored enroute charts (to add things like company radio freqs, and offshore distance limits).

 

[Dave Benjamin]

In regards to TO mins the only thing I'm looking for on a 10-9 is whether the restriction is something more than "STANDARD." Our Ops Specs only allow us to use reduced TO minimums if the 10-9 does not show mins in excess of Standard. If the 10-9 shows greater than Standard mins then we have to use them. If it's standard or less we use what's provided in Chap C of our Ops Specs.