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Intersection takeoff in LVO

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Intersection takeoff in LVO

Old 28th Oct 2013, 18:26
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Intersection takeoff in LVO

Guys, I had a FO asking if an intersection takeoff from LVO would be legal.
At first I thought no, but on a second thought I never seen anything about it anywhere.
Imagine this: RVR 150, 1 transmisometer down, intersection close to mid one, on that intersection ASDA is ok. Would it be viable under EU.OPS? Honestly I don't know, I think it wouldn't be legal, but I really would like to hear from you. Many thanks
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Old 28th Oct 2013, 18:35
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Not sure if it would be legal or not to accept such a clearance.

Pretty sure illegal to offer it though.

Therefore, likely to remain an 'academic' question only.
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Old 28th Oct 2013, 18:49
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That is my belief also, I surely wouldn't take it, but not sure if it really is illegal...
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Old 28th Oct 2013, 19:58
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Hi Flybartfcp,
RVR 150, 1 transmisometer down, intersection close to mid one, on that intersection ASDA is ok. Would it be viable under EU.OPS?
Affirm.
Also the us touch down RVR could be replaced by pilot assessment, permitting take off from full length.
If the stop end RVR was us, but the ASD was OK for the first 2/3rds of the runway, then you may ignore the stop end RVR because it would not be "relevant".
There are rules to permit most sensible operations.

Last edited by rudderrudderrat; 28th Oct 2013 at 20:01. Reason: Spelling
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Old 28th Oct 2013, 20:13
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Is it legal.

No. The question should be why you are considering doing this. Being legal or not does not protect you from an accident, but considering the risks in the situation might.
Does the airport have a designated LVO taxi pattern, equipped with ground radar, could the intersection be mis-identified, etc …

There may not be any specific regulation, but there is for the Captain’s responsibility for the safety of the flight.
Is it safe, this requires judgement not legality.
The question is not how can we do this (is it legal), but should we be thinking of doing this.

Last edited by safetypee; 28th Oct 2013 at 20:16. Reason: typo
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Old 28th Oct 2013, 21:03
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In Porto, Ryanair is regulary taking off during LVP from the intersection which is nearly at half the total RWY length...

They were even allowed to line-up at the intersection while we were backtracking for a full length departure ... To me a proof of very bad airmanship and atc.
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Old 28th Oct 2013, 22:25
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Some airlines require reading of the runway designator painted on the runway prior to takeoff during LVPs, to ensure correct runway etc. Pretty hard to do this if you're taking off from an intersection...

Last edited by NZScion; 28th Oct 2013 at 22:26.
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Old 29th Oct 2013, 16:09
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afaik yes as long as you have asda and performance, same theory as using only the first 2 rvrs if you can stop within the first 2/3rds of runway

only restriction i know is for 125m where the 15m lights are need for guidance aswell as assessment
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Old 29th Oct 2013, 16:47
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Hi binzer,
only restriction i know is for 125m where the 15m lights are need for guidance aswell as assessment
That's impossible to do at airports with inset landing thresholds (eg LGW 26L). When lining up from M3 (full length), the center line lights are 30m apart as they form part of the approach lighting.
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Old 29th Oct 2013, 20:48
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hi rudderrudderrat

yep know what you mean, but on the sim sessions i've done for 125 rvr, we're told we have to move forward to the 15 m lighting for 125 rvr as its part of the requirements. unfortunately performance needs to be calc'd again
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Old 29th Oct 2013, 22:10
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Hi binzer,
we're told we have to move forward to the 15 m lighting for 125 rvr as its part of the requirements.
As pilots, you are permitted to asses the visual requirements during the first part of the take off roll. (The maths is not that difficult knowing the lights are 30m apart). If you asses you can see adequately then you may continue the take off knowing that the reported RVR further along the runway is satisfactory and that you will have 15m light spacing.

e.g. Consider LGW 08R.
If you lined up at J, the 15m lighting starts 377m along the runway near G.
So having lined up at J, are you seriously expected to taxi over 300m to look at the visual clues adjacent to G?
Otherwise, you may as well taxi the full length of the runway and confirm the mid point and stop end visual requirements are also satisfactory.

Last edited by rudderrudderrat; 29th Oct 2013 at 23:54.
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Old 30th Oct 2013, 00:10
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Simple answer is don't line up at J. However, if you do then yes you must taxi forward until you satisfy the correct requirements.

This is one of the requirements for a Low Vis (150/125m) take off lifted straight out of my Part A:

High intensity runway centreline lights spaced 15 m or less and high intensity edge lights spaced 60 m or less are in operation
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Old 30th Oct 2013, 00:47
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EU-OPS about 125 m take offs:

(i) Subject to the approval of the Authority, and provided the requirements in paragraphs (A) to (E) below have been satisfied, an operator may reduce the take-off minima to 125 m RVR (Category A, B and C aeroplanes) or 150 m RVR (Category D aeroplanes) when:
(A) Low visibility procedures are in force;
(B) High intensity runway centreline lights spaced 15 m or less and high intensity edge lights spaced 60 m or less are in operation;
(C) Flight crew members have satisfactorily completed training in a flight simulator;
(D) A 90 m visual segment is available from the cockpit at the start of the take-off run; and
(E) The required RVR value has been achieved for all of the relevant RVR reporting points.

My understanding is that pilot assessment cannot replace RVR readings for take-offs in 125 m visibility. And taking the book literally I guess you need 15 meter spacing from the start of your take off. But this is not the case at LGW you say?
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Old 30th Oct 2013, 03:28
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Hi 172_driver & Lord Spandex Masher,

Please see this map of LGW.
http://www.ead.eurocontrol.int/eadba...2013-07-25.pdf
Low ViS Ops Procedures:
"1.3.3. DEPARTURE
1.3.3.1. RWY 08R
Entry via CAT III holding point at H3, J3, J4 or J7."

We are not replacing RVR readings for take-offs in 125 m visibility, we are confirming that the required visibility has been met using 30m spacing lights at the start of the take off roll, and verifying A 90 m visual segment is available from the cockpit at the start of the take-off run. All the RWCL lights are 15m apart after the landing threshold where the Touch down, mid point and stop end RVRs have been measured.

According to your logic, are we and ATC all wasting our time entering RW08 via J during low vis ops?

Last edited by rudderrudderrat; 30th Oct 2013 at 03:30.
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Old 30th Oct 2013, 09:16
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RRR, from my Part A again:
A minimum of 90 metres visual segment (six centre-line lights visible from the cockpit).

...and...

In the absence of, or as a substitute for the TDZ RVR, the Commander may make a visual assessment. Take-off is permitted provided the assessed TDZ RVR is equal to or greater than 150 m. A minimum of ten centreline lights should be visible from the cockpit.

Both of which require 15m spaced center line lights.

So the answer to your question has to be yes.
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Old 30th Oct 2013, 09:25
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Hi,

I was merely copying the text from the big Bible.

I for one understand that in real life rules and procedures are somewhat interpreted to fit reality. Ask 10 pilots - get 11 answers…
My interpretation is still that for less than the standard 150 m take-off minima (where you can replace RVR with pilot assessment), you technically need RVR readings giving at least 125 for the relevant parts.

Starting the take-off roll from J does not seem to fully comply with 15 m spacing, but hey.. if it's been done before why stop now..
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Old 30th Oct 2013, 11:42
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Intersection takeoff in LVO

Well, they are "in operation", just starting slightly ahead!
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Old 30th Oct 2013, 14:36
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Hi Lord Spandex Masher,

It sounds like your company's Flight Technical Department has added to the rules by specifying the number of lights to be counted and prevented themselves from taking off from J in LVOs at LGW.

I hope they have pointed this problem out to their crews and ask you to do the performance calculation from G.
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Old 31st Oct 2013, 00:26
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No, they're implying that 15m spaced centerline lights should be used. Which is exactly what EUOPS says.

It's a bit pointless having 15m spacing where you can't see them when they're required for 125m take offs.

Might as well bung a couple of 15m spaced lights at the far end of the runway then...after all they are in operation, no?
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Old 31st Oct 2013, 04:19
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Hi Lord Spandex Masher,
Might as well bung a couple of 15m spaced lights at the far end of the runway then...after all they are in operation, no?
No - because all the relevant sections of the runway have to have both the RVR & 15m CL Lighting, so that would include the touch down, mid point & stop end area, no?

172_driver quoted the regulations correctly - they don't specify the number of lights to be counted - only that "A 90 m visual segment is available from the cockpit at the start of the take-off run;"

If your OPS manual tells you to count N lights, then that's what you have to do. Better tell LGW Tower that you'll be taxing >300m forward, stop and count some lights before you start your take off roll though. Since LGW 08R lighting is approved for 125m TO, you'd think that your procedure would specified in the LVO notes, wouldn't you?
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