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bluuskii
22nd Jan 2011, 14:37
Already did a forum search and found a similar topic in the tech log forum but it still was ambiguous..

Under Jar ops, we need 125m for all relevant reporting points and pilot assessment can be substituted for the TDZ.

If you're about to line up and tower now says TDZ 125m, mid 125m, rollout unavailable, can we legally depart..

Likewise, if tower says TDZ 125m, mid unavailable, rollout 125m, can we legally depart.

siftydog
22nd Jan 2011, 15:05
Depends on where you think an RTO just before V1 will leave you. If at the stop end, the answer would be no I think. At least that's my interpretation of 'relevant sectors'.

Sifty

towser
22nd Jan 2011, 15:12
If the midpoint or touchdown are not reported then they can be substituted for each other. So in your second example it effectively means you take it as 125m/125m/125m. So in your scenario then yes you can depart. The only thing that will stop you departing , I believe, is a reported RVR below minima.

KBPsen
22nd Jan 2011, 15:17
Are you sure you can replace TDZ RVR with a pilot assessment when RVR is 125 m?

As hinted at, you need RVRs for the relevant sectors. What is relevant would depend on ASD versus runway lenght. I doubt many people will know actual ASD for a given take-off.

For me it is easy as our ops-specs says RVR for all 3 sectors are required.

potkettleblack
22nd Jan 2011, 15:51
Under Jar ops, we need 125m for all relevant reporting points and pilot assessment can be substituted for the TDZ.

Our airline is now operating under EASA or EU-OPS. I am 99% sure the above has now been superceded. Now we need the visual segment on line up in addition to the RVR. Previously we could take off if we had the 90m segment (6 lights) irrespective of the reported RVR but that is not the case now under EU-OPS.

Your airline may still be operating under JAR in which case please disregard.

gatbusdriver
22nd Jan 2011, 18:59
My understanding is that you can only make a visual assessment for 150m but not 125m.

towser
23rd Jan 2011, 10:28
I can't find any reference for only being able to use pilot assessment if its 150m and not if its 125m. Our ops manual says all required RVR must be achieved for all relevant RVR reporting points but that 'The reported RVR/Visibilty representative of the initial part of the take off run may be replaced by pilot assessment'. In our case the stop end RVR is not relevant for either take off or landing.

Sir George Cayley
25th Jan 2011, 19:28
If you are going to count lights it might be worth knowing what distance apart they are. And there's two to choose from.

SGC

411A
25th Jan 2011, 20:58
For our ops...125 meters RVR required, prior to brakes release.
Seems to me...entirely reasonable.
Type, Lockheed L1011.