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gadjo
7th Feb 2006, 21:34
We did a lahso (land and hold short) landing yesterday with a 737 landing on the crossing runway (clearly visible from the cabin).

On exiting the aircraft in (Adelaide, Australia), a flustered English passenger expressed his concern regarding the safety of this procedure. He added that he had never seen that done before and was afraid of the consequences should the active aircraft (the one holding short, us in this case) failed to stop in time.

Can anyone please tell me wether LAHSO are in operations elswhere in the world and wether it is controversial.

Thank you.

Jerricho
7th Feb 2006, 22:13
Ahhh, the good old LAHSO (or SIRO, or whatever).

Used here in Canada when our runways aren't contaminated with snow etc (wet runways increase the distances)

We have some operators who will not participate (requirement to inform ATC on first contact) either actively ie the one holding short or passively (on the receiving end ;) ) and even have one or two drivers for the regular operators that normally do that inform us they won't. It is a very useful procedure, although on radar it can look hideous. I'm guessing so many arguments can be put up regarding "Well, you can land on a runway of xxxx ft, what's wrong with landing on a runway of twice the distance and stop before the intersecting?". And (touch wood) I have never seen it, but a double go-around could be a little interesting for all involved.

From what I understand, it's not something pilots like to have droped on them at the last minute. I'm sure some of our drivers out there will be able to expand on this.

Port Strobe
7th Feb 2006, 22:39
I'm not entirely familiar with the LAHSO procedure myself (never come across it in the UK) but from what I can gather from two posts it's used for intersecting runways both being active and one get's told not to extend the landing run into the other.
On the back of Jerricho's comment about a double go around I was in this situation myself last week where the extended centreline at the upwind end of the runway I was on goes across the runway the other traffic was on, so not technically intersecting runways. I was in a light a/c and the other was also a light (but heaver than me :ouch: ) a/c and we were VFR so in the go around the rules are see and avoid. If we'd been IFR wouldn't this have compromised separation and so never been given clearance for similtaneous approaches? The other a/c passed directly over me in the go around because I kept my height in check to avoid collision. I just wanted to confirm what would happen with IFR traffic in this situation?
Cheers

Jerricho
7th Feb 2006, 23:12
Port, you got the idea. For example here in Winnipeg, our runway 18 is 11000 feet long. Using LAHSO we have 7200 available to remain clear for the intersection for our runway 13. Different aircraft categories require different lengths or do not hold short at all (can catch you out as earlier 737s do, yet the NG stuff doesn't have the required length here for the procedure). I can go and dig out the table if somebody wants.

Just to explain a little further (and things are a little different here in Canada to the UK regarding reduced separation in the vicinity of an aerodrome versus anadian Automatic Control Transfer or ACT), for LAHSO to be in effect our tower must be in VFR conditions with ACT in effect. Without VFR ocnditions, terminal/approch controllers cannot utilise LAHSO and must provide standard IFR separation.

TheOddOne
8th Feb 2006, 00:46
When 23 was active at LHR, the normal SOP was 23 arrive, 27R depart.

However, I do recall in the early eighties, some trials with 27L (or 28L, can't remember how long ago!) depart with 23 arrive. I don't think it was strictly LAHSO, but was done more on timing to avoid confliction. As I recall, there were only a few controllers who fancied having a go at it and it all sounded a bit fraught, but quite interesting to watch. A number of the Tridents/1-11s landing 23 would make best efforts to stop well short of block 85, especially if they were bound for the Delta stands.

All gone, now, of course. Are there many civvie airfields in the UK with cross runways capable of supporting this activity?

Cheers,
TOO

Tarq57
8th Feb 2006, 01:30
I'm an aerodrome controller at a single runway airport. Spoken to colleagues "across the ditch" who have operated this. Most don't like it much. Some have seen it fail to work in near spectacular fashion. Personally I wouldn't be too keen. If I worked at a place where this was SOP, I'd attempt to arrange the spacing so that there were no "dead-ringers", ie if the stopping distance was exceeded the other aircraft would have already passed the intersection, or been able to go around.

PortStrobe, I would imagine that in the event of a double IFR go round in this situation, the response of the crews involved would have been similar to yours, perhaps with the additional guidance of TCAS. It would also not be surprising to see a couple of very early turns. I would hope that the crews involved would happily accept that the concept of a standard missed approach (if applicable) would be defenestrated in the interests of noise abatement. All in all a fairly fraught situation I hope never to see, nor to experience as a passenger.

bekolblockage
8th Feb 2006, 01:49
Ahhh. The good old days of 27/34 simops (LAHSO) in Melbourne. Throw in northern departures off 34 and the overhead ML procedure for the Essendon bank flights on a hot day. Double go around with an Aerocommander over the intersection at 1500 ft? - :eek: . Do you guys still play that?

KeepItRolling
8th Feb 2006, 02:58
Not so much now, ML tower tends to space the Aero Commanders so that the triple dead heat doesn't happen.

Port Strobe
8th Feb 2006, 04:10
Thanks for the replies guys. I guess from what I've read the situation I was in is strictly confined to VFR, and for good reason!

Cheers

HEATHROW DIRECTOR
8th Feb 2006, 07:23
<<However, I do recall in the early eighties, some trials with 27L (or 28L, can't remember how long ago!) depart with 23 arrive. I don't think it was strictly LAHSO, but was done more on timing to avoid confliction.>>

23 against 28L departing was no problem, although that config was rarely used, and I don't recall any special procedures. 23(L) versus 28L landing was a radar controlled operation and there never was a laid down procedure for the use of both runways - just pure radar skill. If the wind on 23 dropped off the results could get exciting to say the least and a colleague faced with such a situation asked the 23 lander if he could land and hold short of 28L. For the 23 lander, being a clockwork mouse, it was no trouble and he cleared on the southern dual carriageway, miles before 28L. The pilot of the tiddler was mightily impressed with the "procedure" and wrote to the boss at Heathrow to offer thanks, etc. My colleague's feet never touched the floor as he was hauled downstairs to stand on the boss's bit of Axminster!!! We were emphatically instructed that LAHSO was not permitted!

chevvron
8th Feb 2006, 07:55
Watched it once on my one and only visit to Newark. Watching a DC10 land on the cross runway (looked like he did a visual) when two DC9's appeared,(restricted view from the terminal building) one on each of the two parallel main runways, both slowing to a halt.

tired
8th Feb 2006, 10:32
To answer dagjo's original question, LAHSO used extensively in the States. Didn't actually realise that Canada and Oz uses it too, so I've learn't something here :)

My mob (LHR-based longhaul operator) is not allowed by our Ops manual to participate in LAHSO ops - we must decline if offered. I think I'm correct in saying that the (UK) CAA bans - or, probably more correctly, declines to authorise - UK operators participation in LAHSO ops.

t

Jerricho
8th Feb 2006, 14:21
Tired, when you say participate, do you mean totally, as in not authorised to be the passive lander either?

letMfly
8th Feb 2006, 14:48
All gone, now, of course. Are there many civvie airfields in the UK with cross runways capable of supporting this activity?
LAHSO is used a lot at Aberdeen, but the LAHSO aircraft has to be a helicopter! Even so, there are several requirements to be met and a load of tongue-tying phraseology to be issued to both aircraft involved before the procedure can be used.

letMfly

tired
8th Feb 2006, 15:10
Jerricho - yes! Not allowed to participate at all in either capacity.

Spitoon
8th Feb 2006, 16:04
If I'm not mistaken, despite LAHSO is in the ICAO books, the UK does not play - perhaps with the exception of helis at PD - either at UK airports or with UK operators wherever they are because it's so darned dangerous!

Nah, sorry! Shouldn't use such emotive words. What I meant was that it couldn't pas a safety assessment in a month of Sundays.

Euroc5175
8th Feb 2006, 16:18
LAHSO procedures have been the subject of much debate during the IFATCA Technical and Operations Committee (TOC) meetings this year.
A draft Working Paper has been reviewed at both TOC meetings, and despite a considerable amount of time spent by the Committee debating the issues, a concensus could not be reached with all the TOC members (comprising multiple nationalities and various ATC disciplines). There were concerns expressed by a number of members, especially regarding controller liability, the delegation of separation, the concept of segregation rather than separation, and the general safety issue of a double go-around.
A LAHSO working paper will still be put to Committee B at the annual IFATCA Conference in April. However, rather than being a TOC submitted paper, it will probably be submitted by an individual Member Association (Australia) or as an Executive Board paper by the current Executive Vice President Technical (an Australian!).
LAHSO procedures are certainly in use in the USA, Canada and Australia. The only place I'm aware that they are used in the UK is Aberdeen, and this is, has been previously highlighted, reserved for helicopter ops.
If anyone is interested in having a copy of the Working Paper drop me an e-mail and I'll forward you a copy once the IFATCA Office distributes all the Conference papers.

Jerricho
8th Feb 2006, 16:35
Euroc, please check you Private Messages. :ok: