In the UK at least, the front cover of this week's Economist is headlined 'Heathrow - Our Solution'.

http://www.economist.com/news/leader...rport-capacity-it-needs-reasonable

They cover the topic in a leader and also in a briefing. The gist of their proposal is to build four new runways over a reservoir (and the M25) to the immediate west of LHR's current position. The new runways would be parallel and in pairs. You can see the map of what they propose on near the bottom of the article below.

http://www.economist.com/news/briefi...rt-capacity-its-capital-going-need

Could this work? The reasons they give include reduced noise (as late final approach from the east would be over the 'old' airport rather than Myrtle Avenue etc.), avoidance of having to relocate staff/businesses across London to a Boris Island or Thames Hub, and bringing relatively few new people into the >55dB noise envelope (as the third runway to the north idea would).

What would they do with the current runways? I'm guessing they would just become taxiways like at LGW.

There are about 30 airports in the world that badly need a third runway, but they could also use 4... Is not just LHR with a room to expnad issue

Ahh this proposal again. There have been several threads covering the four runways to the west idea.

Quoting Eltomzo (Thread starter): Could this work?

No. Although the principle has merit, the design/operation envisaged by Tim Leonig is not remotely certifiable according to design regulations (or practical) and therefore could not be built. Using even the very minimum runway/taxiway spacing for parallel runways it would require the demolition of Terminal 5 and reduce the central area to a slither barely 100m wide - leaving no space for a terminal, as this graphic I drew up before demonstrates:



Brown = 300m runway strip
Pale brown = runway
Green = central taxiway
Blue = Taxiway strip

To achieve the desired flexibility (with runway operations) and central terminal area in Tim Leonig's plan you would need a footprint and layout like this:



My suggestion however is to use a layout similar to Manchester Airport. It is possible to add two offset parallel outer runways to the west at minimum separation (390m) and still meet certification requirements. The east and west runways could operate independently, arrivals on one pair and departures on the other. Parallel taxiways beside the two new runways wouldn't be needed as no aircraft would be landing on 27 or departing from 09, so the land footprint for the two new runways would be minimal; a 300-350m wide strip for each:



Oh, and if they chose this option, I'll send them an invoice for my services 


Dan  

The problem with Heathrow expansion is not ideas, there are plenty of those.

The problem is political will and power - few people outside the aviation industry want to expand Heathrow, and any politician who has leverage to bring a solution to fruition still has to face the prospect that the people that vote them in may not continue to vote them in if expansion went ahead.

Quoting moo (Reply 4): The problem is political will and power - few people outside the aviation industry want to expand Heathrow, and any politician who has leverage to bring a solution to fruition still has to face the prospect that the people that vote them in may not continue to vote them in if expansion went ahead.

I'm not so sure any more. In my view the Airports Commission is shaping up to be the vehicle which drives the will and creates the political rational for expanding Heathrow. I also feel there is growing public support for expanding our airport capacity, with a solid evidence base I can see there being a political platform to stand on and I can see the Conservatives doing that at the next election.


Dan  

Not to be a troll here, but LHR has 4 runways.

Runways go both ways, people  

Quoting lightsaber (Reply 7): 7. LGW (a question of when, not if)

LGW may have a minor obstacle to their preferred second runway site, namely the headquarters of the CAA. It's a large office block which IIRC is bang on the extended centerline.


Dan  

Quoting lightsaber (Reply 7): I have trouble coming up with 30 airports really that constrained which are not expanding already.

You may have forgotten MEX. There is no space to expand there. They need desperately to come up with a solution (there are a few, but not enough political power was in place within the last 2 governments, especially since Mr Fox's government backtracked with the "macheteros" protests.

All in all, MEX must expand/build new airport soon. But MEX is not in the top 50 anymore (but close enough)

If there is a large accident over central London, that would probably hurry up a solution. It is a bit scary thinking about how many large aircraft fly over the very densely populated London every hour.

Quoting PlymSpotter (Reply 8): LGW may have a minor obstacle to their preferred second runway site, namely the headquarters of the CAA. It's a large office block which IIRC is bang on the extended centerline.

IIRC from some old diagrams drawn up some years ago by the then BAA, they took this into consideration and gave it a huge displaced threshold, quite a bit more than what is on the current 26L.

Quoting lightsaber (Reply 6): Will you ride in a plane playing chicken with another aircraft?

Hell no  

I do think expansion is overdue but there's not many places to expand to; hence the discussions about an entirely new airport.

Quoting PlymSpotter (Reply 5): I also feel there is growing public support for expanding our airport capacity, with a solid evidence base I can see there being a political platform to stand on and I can see the Conservatives doing that at the next election.

So, the same people elected on a pledge for a third runway over their dead bodies would now campaign for four news runways ? Make sense... not !

Quoting sweair (Reply 9): If there is a large accident over central London, that would probably hurry up a solution. It is a bit scary thinking about how many large aircraft fly over the very densely populated London every hour.

As it would anywhere that you find planes and people.

Quoting kdhurst380 (Reply 10): IIRC from some old diagrams drawn up some years ago by the then BAA, they took this into consideration and gave it a huge displaced threshold, quite a bit more than what is on the current 26L.

Interesting thanks, I've only seen drawings without markings.

Quoting Aesma (Reply 12): So, the same people elected on a pledge for a third runway over their dead bodies would now campaign for four news runways ? Make sense... not !

I've noticed over the past year that 'the third runway' has increasingly become a reference specifically to the Sipson plan. A lot of internal party politics came to a head during Justine Greening's tenure as minister for transport, risking a major backlash against the party policy - Greening represents a constituency under LHR's flightpath and is vehemently opposed to LHR expansion, being a former campaigner against it. Within a month of Patrick McGloughlin replacing her the Airport's Commission had been launched into hub capacity - that's a pretty sharp change of direction.


Dan  

Quoting PlymSpotter (Reply 2): My suggestion however is to use a layout similar to Manchester Airport. It is possible to add two offset parallel outer runways to the west at minimum separation (390m) and still meet certification requirements.

The only problem I can see there is that when on a west configuration you'll have to cross departing aircraft over the current runways (which would be used for landing) in order to get the new runways for takeoff. It obviously works at MAN, but with the way that LHR spaces their arrivals that might not be so practical unless you built an end-around taxiway far to the west or east to get around the current runways without impacting arrivals. Or you could increase the arrival spacing, which would lower the arrival rate per runway, but you'd still come out somewhat ahead since you could use two runways for arrivals instead of one.

But for an east configuration it would be great.

-Mir

Quoting Mir (Reply 15): The only problem I can see there is that when on a west configuration you'll have to cross departing aircraft over the current runways (which would be used for landing) in order to get the new runways for takeoff. It obviously works at MAN, but with the way that LHR spaces their arrivals that might not be so practical unless you built an end-around taxiway far to the west or east to get around the current runways without impacting arrivals.

Yes indeed, a central taxiway would be located between the current and new runways, accessible via link taxiways around the end of the current runway 27s. These link taxiway would feed into the current infrastructure at a point between T5 and T5B, so the backtrack to reach the new pair of 27s (most likely 28L/R) would not be that great. To achieve an adequate safety area, the landing distances for the current 27s would be shortened, but with 27L currently having an LDA of 3,660m and 27R some 3,884m, knocking them down to around 3,000m would present no significant operational issues.


Dan  

Quoting PlymSpotter (Reply 16): To achieve an adequate safety area, the landing distances for the current 27s would be shortened, but with 27L currently having an LDA of 3,660m and 27R some 3,884m, knocking them down to around 3,000m would present no significant operational issues.

3000m seems a bit short for takeoffs, which the runways would still need to be able to support in the easterly direction. If you gave 27R a displaced threshold of 500m or so, you could put a taxiway on the east side of the airport and have aircraft from T1 go around that way onto a taxiway north of the airport (where the current perimeter road is). That wouldn't affect takeoffs from 9L at all. The other taxiway would probably have to be just to the west of the west perimeter road.

-Mir

Quoting Mir (Reply 17): 3000m seems a bit short for takeoffs, which the runways would still need to be able to support in the easterly direction.

Only for a select number of heavies - A343s, 77Ws and 744s mainly when departing very close to MTOW. There would be no significant change to the declared take off distances for 09L/R, so you would still have 3,500m+ TORA available if needed. However a departure using the full length would effectively halt movements on the link taxiway, due to jet blast, but as >95% of movements don't need the full TORA length, the majority could depart from an intersection with sufficient spacing that the blast does not affect the taxiway. Intersection departures would still have around 3050m TORA for 09R and 3150m for 09L.


Dan  

Quoting PlymSpotter (Reply 2): My suggestion however is to use a layout similar to Manchester Airport. It is possible to add two offset parallel outer runways to the west at minimum separation (390m) and still meet certification requirements. The east and west runways could operate independently, arrivals on one pair and departures on the other. Parallel taxiways beside the two new runways wouldn't be needed as no aircraft would be landing on 27 or departing from 09, so the land footprint for the two new runways would be minimal; a 300-350m wide strip for each:

On that note I always wondered why they didn't try to build that 3rd runway where cargo and T4 are currently located, rather than the latest proposal north of Bath Rd. It seems to me that there is almost enough space there for a 3rd runway, and they could have relocated the cargo center to that space north of Bath Rd. It's a lot easier to move containers over than distance than it is to handle passengers. Or maybe that option was considered and rejected too, and i just missed it.

Quoting airbazar (Reply 19): On that note I always wondered why they didn't try to build that 3rd runway where cargo and T4 are currently located, rather than the latest proposal north of Bath Rd.

Because they can't be side by side if you want to operate them simultaneously - they can be parallel, but there must be a stagger. Off the top of my head the separation should be 790m for dependent simultaneous operation of runways with parallel thresholds, but for every 150m which the thresholds are staggered this can be reduced, until you end up with a large stagger and the minimum separation of 390m - just enough to slip a Code F taxiway down the middle.


Dan  

Technology will overtake many of the problems that impact LHR before a) the politicians would be able to get an expansion approved in the first place (we are talking years here - T5 from studies to approval took about 10 years), and b) if expansion is approved, the actual build will take YEARS (T5 took about 6 years). Add the two together and you are looking at 15 years min before the "new" LHR is up and running.

Quoting planemaker (Reply 21): Technology will overtake many of the problems that impact LHR

Not unless we can learn how to control the weather. And believe me, if any country could have gained control of the weather by now and stopped it raining, it would have been the UK.  


Dan  

Quoting PlymSpotter (Reply 22): Not unless we can learn how to control the weather. And believe me, if any country could have gained control of the weather by now and stopped it raining, it would have been the UK.

BTW, I do like your proposal... and with some variations it could work well.

We wouldn't "need" to control the weather... we already have technology that would allow zero-zero visual approaches and takeoffs.

Back in the 70's Heathrow was a criss cross of 5 runways though never used as such. These runways have now been covered with terminals. If this 4 runways scheme is adopted then I shouul imagine the current runways will quickly be covered with new terminals and jetways.

Quoting planemaker (Reply 23): BTW, I do like your proposal...

Thank you

Quoting planemaker (Reply 23): We wouldn't "need" to control the weather... we already have technology that would allow zero-zero visual approaches and takeoffs.

Indeed, but it reduces the flow rate. Such approaches are already used at LHR, but I'm not aware of any forthcoming change in regulations which will allow the landing rate to be sufficiently sped up that capacity isn't slashed whenever the fog/rain... comes in. Then there is also the issue with ice/snow and runway contamination - you can't retrospectively install a heating system and closing down a runway for months to do this would not be feasible.

Quoting goosebayguy (Reply 24): If this 4 runways scheme is adopted then I shouul imagine the current runways will quickly be covered with new terminals and jetways.

Unlikely, much of the current runways would be in the PSZs of the new runways, which will prohibit development.


Dan  

Quoting airbazar (Reply 19): On that note I always wondered why they didn't try to build that 3rd runway where cargo and T4 are currently located,

   They should have preserved that land for that purpose long before they built T4 and the BA cargo center.

Quoting PlymSpotter (Reply 20): Because they can't be side by side if you want to operate them simultaneously - they can be parallel, but there must be a stagger. Off the top of my head the separation should be 790m for dependent simultaneous operation of runways with parallel thresholds, but for every 150m which the thresholds are staggered this can be reduced, until you end up with a large stagger and the minimum separation of 390m - just enough to slip a Code F taxiway down the middle.

This is true for simultaneous dependent operations of the same type (i.e. two simultaneous arrivals) in IFR weather. However the point being made is a configuration for segregated operations - one arrival and one departure on close spaced parallel runways. The departing aircraft is in position and receives its takeoff clearance the moment the arrival touches down as if its one 'operation', and so on. In VFR weather, you wouldn't even have that restriction. I don't even consider it a restriction, as wake turbulence separation is more limiting on capacity. Look at all the airports around the world with a similar arrangement - ATL, DFW, CDG, PVG, ICN.. the list goes on and on.

[Edited 2013-03-29 15:20:21]

Quoting PlymSpotter (Reply 25): Such approaches are already used at LHR, but I'm not aware of any forthcoming change in regulations which will allow the landing rate to be sufficiently sped up that capacity isn't slashed whenever the fog/rain... comes in.

I really was quite opaque in my post. The technology exists today but it has a way to go before full implementation on the ATC side and very few aircraft currently have the "black boxes" for visual zero-zero (and the regs haven't caught up yet, anyhow). But my point was that by the time that expansion were to become a reality, NextGen/SESAR would be functional and LHR bound aircraft would be equipped with enhanced EVS/SVS + HUDS.

Quoting PlymSpotter (Reply 25): Then there is also the issue with ice/snow and runway contamination - you can't retrospectively install a heating system and closing down a runway for months to do this would not be feasible.

Very true! However... by the time "the expansion" were to be operational there could be some options developed that would not require the closure of any runway.

Quoting PITrules (Reply 26): This is true for simultaneous dependent operations of the same type (i.e. two simultaneous arrivals) in IFR weather.

It isn't actually. For simultaneous dependent IFR arrivals you need a minimum spacing of 915m.

Quoting PITrules (Reply 26): However the point being made is a configuration for segregated operations - one arrival and one departure on close spaced parallel runways. The departing aircraft is in position and receives its takeoff clearance the moment the arrival touches down as if its one 'operation', and so on.

Yes I understand that, I should have said segregated not dependent simultaneous - my apologies. But the issue is still present; the minimum centerline spacing for parallel segregated operations under IFR is 760m (slightly less than the 790m I was remembering off the top of my head). This can be reduced by 30m for every 150m that the arrival runway is staggered towards arriving aircraft, down to a minimum separation of 300m, although in practice you need 390m as a very minimum to enable a central taxiway.

Say a new runway 27L was staggered by 1000m from the current threshold of 27L, that still means the separation between the two runways needs to be 550m. But this is presuming the threshold of the new 09R is also staggered 1000m before the current one. In practice a third runway doesn't need to be almost 4000m long, so you would either end up with a much longer runway than is needed or have to trade lower spacing for a shorter runway.

Quoting PITrules (Reply 26): I don't even consider it a restriction

At LHR you really should do. VFR can't be relied upon.

Quoting PITrules (Reply 26): Look at all the airports around the world with a similar arrangement - ATL, DFW, CDG, PVG, ICN.. the list goes on and on.

Unfortunately that's not how aerodrome licensing works in the UK. Just because other airports have chosen not to adhere to ICAO regulations doesn't mean that the CAA will allow it - they do things by the rulebook and are generally accepted to be the strictest aviation authority in existence. The second runway at MAN and the proposed second runways at STN and LGW all came across the same spacing issues.


Dan  

Quoting planemaker (Reply 27): I really was quite opaque in my post. The technology exists today but it has a way to go before full implementation on the ATC side and very few aircraft currently have the "black boxes" for visual zero-zero (and the regs haven't caught up yet, anyhow). But my point was that by the time that expansion were to become a reality, NextGen/SESAR would be functional and LHR bound aircraft would be equipped with enhanced EVS/SVS + HUDS.

I'd like to think the CAA would embrace these ASAP in the interests of safety alone. Although in another year it won't be the CAA's place to write the regulations, so I just hope they implement and changes.


Dan  

Quoting PlymSpotter (Reply 28): It isn't actually. For simultaneous dependent IFR arrivals you need a minimum spacing of 915m.

Didn't I agree on that?

Quoting PlymSpotter (Reply 28): But the issue is still present; the minimum centerline spacing for parallel segregated operations under IFR is 760m (slightly less than the 790m I was remembering off the top of my head). This can be reduced by 30m for every 150m that the arrival runway is staggered towards arriving aircraft, down to a minimum separation of 300m, although in practice you need 390m as a very minimum to enable a central taxiway.

You are totally ignoring the point. No one is suggesting 2 parallel arrivals or 2 parallel departures on close parallel runways, or a truly independent simultaneous ability of a combination thereof. What was said was:

Quoting PITrules (Reply 26): - one arrival and one departure on close spaced parallel runways. The departing aircraft is in position and receives its takeoff clearance the moment the arrival touches down as if its one 'operation', and so on. In VFR weather, you wouldn't even have that restriction. I don't even consider it a restriction, as wake turbulence separation is more limiting on capacity.

.

Quoting PlymSpotter (Reply 28): At LHR you really should do. VFR can't be relied upon.

Again, what was said is that current wake turbulence separation requirements would already account for whatever delay there would be in waiting to clear an aircraft for takeoff just as the other is touching down on the parallel.

Quoting PlymSpotter (Reply 28): Just because other airports have chosen not to adhere to ICAO regulations doesn't mean that the CAA will allow it

I don't see how the airports listed are all ignoring ICAO regulations?

[Edited 2013-03-29 17:44:52]

[Edited 2013-03-29 18:32:42]

Quoting PITrules (Reply 30): Didn't I agree on that?

No, you said that my comment regarding 790 (760m) spacing was true for simultaneous dependent operations of the same type. The correct spacing is in fact 915m.

Quoting PITrules (Reply 30): You are totally ignoring the point. No one is suggesting 2 parallel arrivals or 2 parallel departures on close parallel runways

No, I'm not, because that's not what I am saying either. Otherwise, why would I have written 'the arrival runway is staggered towards arriving aircraft'. Note it's singular, I am talking about only having one arriving runway, you can't stagger two arriving runways away from each other!

Quoting PITrules (Reply 30): What was said was: Quoting PITrules (Reply 26): - one arrival and one departure on close spaced parallel runways. The departing aircraft is in position and receives its takeoff clearance the moment the arrival touches down as if its one 'operation', and so on. In VFR weather, you wouldn't even have that restriction. I don't even consider it a restriction, as wake turbulence separation is more limiting on capacity.

OK, so in a nutshell that first sentence is a reasonable definition of parallel segregated operations. It doesn't matter if the departing aircraft is sat on the runway waiting for clearance or if it's already rolling when the arriving aircraft touches down, you are still operating two segregated parallel runways. It therefore doesn't change the fact that regulations stipulate adequate spacing between runway centerlines to put it into operation. Whatever other separation/operation (possibly FAA?) you are thinking about, forget it - the CAA have not allowed it in the past and will not allow it now.

Quoting PITrules (Reply 30): Again, what was said is that current wake turbulence separation requirements would already account for whatever delay there would be in waiting to clear an aircraft for takeoff just as the other is touching down on the parallel.

The thing is, all those little delays add up to a heck of a lot when you are operating at the kind of capacity which LHR experiences. For your suggestion to work you would essentially have to treat two physical runways as one, so operationally you are not getting a new runway. To factor in this mode of operation the arrival rate would have to be slowed quite considerably, excessively so compared to a segregated operation, pretty much to the point that you have no gain. It also defeats much of the object of adding a third runway, which is to maintain normal operations in the event that a runway is taken out of use.

Quoting PITrules (Reply 30): I don't see how the airports listed are all ignoring ICAO regulations?

A lot of airports ignore a lot of regulations, the US not being an exception, whilst conversely the CAA follows rules to the letter in most cases. Often discrepancies arise because the infrastructure was laid down before the current regulations/aircraft sizes existed and therefore these irregularities are given dispensations. Or because the various national aviation authorities have their own standards which pick and chose which bits of ICAO to follow - very often this involves allowing IFR based on VFR design standards.


Dan  

Quoting PlymSpotter (Reply 31): No, you said that my comment regarding 790 (760m) spacing was true for simultaneous dependent operations of the same type. The correct spacing is in fact 915m.

Well it was your comment after all ...

Quoting PlymSpotter (Reply 20): separation should be 790m for dependent simultaneous operation of runways with parallel thresholds,

and also said...

Quoting PlymSpotter (Reply 28): For simultaneous dependent IFR arrivals you need a minimum spacing of 915m.

.

Quoting PlymSpotter (Reply 31): No, I'm not, because that's not what I am saying either

Well, yes, you were up until your last post.

Quoting PlymSpotter (Reply 31): Otherwise, why would I have written 'the arrival runway is staggered towards arriving aircraft'. Note it's singular, I am talking about only having one arriving runway, you can't stagger two arriving runways away from each other!

You don't need to stagger one runway away from the other. Again, there are plenty of examples around the world.

Quoting PlymSpotter (Reply 31): The thing is, all those little delays add up to a heck of a lot when you are operating at the kind of capacity which LHR experiences

That's quite odd, that a third runway would cause increased delays. But of course its not true.

Quoting PlymSpotter (Reply 31): For your suggestion to work you would essentially have to treat two physical runways as one, so operationally you are not getting a new runway. To factor in this mode of operation the arrival rate would have to be slowed quite considerably, excessively so compared to a segregated operation, pretty much to the point that you have no gain. It also defeats much of the object of adding a third runway, which is to maintain normal operations in the event that a runway is taken out of use.

Finally, the heart of the matter. It's not just a "suggestion", it is used very practically all over the world. No, arrival rate would not need to be slowed down. In fact, it would remain exactly as is. The departing aircraft is the one which would be paired up with the landing of the arrival aircraft. As long as the arrival stream remains steady, so does the departure stream. Overall capacity is greatly increased as opposed to just the one runway.

[Edited 2013-03-29 19:51:51]

Quoting PITrules (Reply 32): Well it was your comment after all ...

Which I corrected and apologised for using the wrong name in post 20:

Quoting PlymSpotter (Reply 28): Yes I understand that, I should have said segregated not dependent simultaneous - my apologies.

Quoting PITrules (Reply 32): Well, yes, you were up until your last post.

As mentioned I corrected using the wrong name in my first reply to you (Reply 28) and then fully explained what was meant, just as I did in my last post too

Quoting PlymSpotter (Reply 28): Yes I understand that, I should have said segregated not dependent simultaneous - my apologies. But the issue is still present; the minimum centerline spacing for parallel segregated operations under IFR is 760m (slightly less than the 790m I was remembering off the top of my head).

Quoting PITrules (Reply 32): You don't need to stagger one runway away from the other. Again, there are plenty of examples around the world.

If you walked into the CAA aerodrome licensing department and said 'but they do it over there, so it must be OK!' they would promptly laugh you out of the building. That's not how things work, the ICAO and CAA regulations are very clear on design standards. As EASA are drawing their standards from ICAO I expect them to be the same.

Quoting PITrules (Reply 32): Finally, the heart of the matter. It's not just a "suggestion", it is used very practically all over the world

See above. You seem to think you know better though.

Quoting PITrules (Reply 32): No, arrival rate would not need to be slowed down. In fact, it would remain exactly as is.

Sure, you just wouldn't get to use the other runway for departures very often.

Quoting PITrules (Reply 32): The departing aircraft is the one which would be paired up with the landing of the arrival aircraft. As long as the arrival stream remains steady, so does the departure stream. Overall capacity is greatly increased.

In another country, then probably. At Heathrow you couldn't have more than one active aircraft on either runway at the same time, pairing wouldn't be an option, so with that in mind try fitting departures in without compromising the 40-50 arrivals per hour, and then calculate your advantage over the same operation on a single runway

Quoting PITrules (Reply 32): That's quite odd, that a third runway would cause increased delays. But of course its not true.

You're right, that's not what I said there. But thinking about it, when you consider that mixed mode (up to 25% extra capacity, if taken up) wouldn't be an option with two such closely spaced runways, it just might in fact be true.


Dan  

Quoting PlymSpotter (Reply 33): If you walked into the CAA aerodrome licensing department and said 'but they do it over there, so it must be OK!' they would promptly laugh you out of the building. That's not how things work, the ICAO and CAA regulations are very clear on design standards. As EASA are drawing their standards from ICAO I expect them to be the same.

But again, I'm not sure that all these other airports (ATL, ICN, CDG, etc) do not meet ICAO standards. If you're saying the CAA has standards for UK airports above and beyond ICAO, then I would be interested to know why that is.

Quoting PlymSpotter (Reply 33): See above. You seem to think you know better though.

Its not a question of me thinking I know better; I'm simply pointing out what is used very effectively at many other places. Did these other airports waste a huge amount of money building their airfields?

Quoting PlymSpotter (Reply 33): Sure, you just wouldn't get to use the other runway for departures very often.

Quoting PlymSpotter (Reply 33): But thinking about it, when you consider that mixed mode (up to 25% extra capacity, if taken up) wouldn't be an option with two such closely spaced runways, it just might in fact be true.

I don't see why this would be the case. You have your 40-50 arrival rate, then departures paired up with those on the parallel. Try getting that out of a single runway.


Instead of these schemes which will never happen such as building runways 2 miles to the west over a motorway and reservoir, I think a third runway to the immediate south would have been a good compromise, followed by the Sipson site for a 4th.

Quoting PITrules (Reply 34): But again, I'm not sure that all these other airports (ATL, ICN, CDG, etc) do not meet ICAO standards. If you're saying the CAA has standards for UK airports above and beyond ICAO, then I would be interested to know why that is.

The CAA are very conservative, it's only recently that they have come around to the idea of using EMAS as a supplement for insufficient RESAs, despite the FAA providing them with ample information many years previously. Generally though the CAA rules and regs, which I work with daily, are in my opinion the strictest in the world. Even so, look at any UK airport and they will almost certainly be numerous deviations and discrepancies from current rules. That's dealt with via dispensations, but when it comes to new or replacement infrastructure the rule book is followed to the letter. It can be a pain in the ass at times, but it works and means we have some of the safest airports in the world.

Quoting PITrules (Reply 34): Its not a question of me thinking I know better; I'm simply pointing out what is used very effectively at many other places. Did these other airports waste a huge amount of money building their airfields?

I'm afraid it came across that way. The rational for airport design in other parts of the world may well be 'they've done it, so we'll do it' - standards differ. Also as I mentioned previously, many other facilities are only designed to VFR standards where ~300m centerline spacing is acceptable, because that is the predominant condition - they may or may not continue the same operation in IFR conditions, I don't know. But, even if certifiable, for Heathrow a VFR reliant design is out of the question. Everything has to be done to IFR standard because that is when the extra capacity is needed most, or all hell would break loose when one runway becomes nonoperational.

Quoting PITrules (Reply 34): I don't see why this would be the case. You have your 40-50 arrival rate, then departures paired up with those on the parallel. Try getting that out of a single runway.

That is the issue, even LGW can only manage around 55 per hour, and that is the world's busiest single runway airport. So at best you would be getting a 5-10% increase in such a scenario, which is anticipated anyway.

Quoting PITrules (Reply 34): I think a third runway to the immediate south would have been a good compromise, followed by the Sipson site for a 4th.

Go South, but far enough for the operation to maximise the runway capacity.


Dan  

Quoting PlymSpotter (Reply 35): That is the issue, even LGW can only manage around 55 per hour, and that is the world's busiest single runway airport. So at best you would be getting a 5-10% increase in such a scenario, which is anticipated anyway.

Considering LGW only has one useable runway, I don't see how it's even a good comparison.

Lets look at the stated IFR design capacity of LHR vs CDG. 370,000 annual IFR ops at LHR (currently being exceeded by 23%) compared to 680,000 at CDG.

The difference of course is that CDG has two additional runways; these are closely spaced parallel runways, yet they increase CDG's IFR capacity by 300,000 over that of LHR. Our discussion at LHR considers one closely spaced parallel runway, so that would be an increase of 150,000 annual movements. Not too shabby, and much greater than what you are alluding to.

Quoting PlymSpotter (Reply 35): That is the issue, even LGW can only manage around 55 per hour, and that is the world's busiest single runway airport. So at best you would be getting a 5-10% increase in such a scenario, which is anticipated anyway

A single runway, in arrival mode only, should be able to accept anywhere between 30 and 50 arrivals per hour (mainly depending on aircraft type mix, and weather conditions). Put a closely spaced parallel runway next to it, and even without any stagger you would be able to virtually double the capacity. The point off course is that all that extra capacity is just departures. You would not be able to put in an extra single arrival (although there are also techniques to go to double mixed mode, where you maybe be able to sneak in some extra arrival capacity, but that heavily depends on weather conditions, and now runway stagger does come into play).

Quoting PlymSpotter (Reply 31): OK, so in a nutshell that first sentence is a reasonable definition of parallel segregated operations. It doesn't matter if the departing aircraft is sat on the runway waiting for clearance or if it's already rolling when the arriving aircraft touches down, you are still operating two segregated parallel runways. It therefore doesn't change the fact that regulations stipulate adequate spacing between runway centerlines to put it into operation. Whatever other separation/operation (possibly FAA?) you are thinking about, forget it - the CAA have not allowed it in the past and will not allow it now

Here you also lost me. On closely spaced parallel runways, you have one runway dedicated for arrivals, and the other dedicated to departures (there are other options, but this is by far the mostly used one). Now you can have the departure aircraft sitting on the departure runway (so not occupying the active arrival runway, and the departure aircraft not interfering with the arrival ILS!) ready to go. As soon as the arrival aircraft is on the ground and committed to stopping, you can have the departure rolling (theoretically even a little sooner, if ATC runway view is not compromised). That departure would be in the air around the same time the landing aircraft clears the arrival runway. By that time in-line horizontal spacing would be sufficient for the next arrival to land.

Now I readily admit that I’m not familiar (at all) with ICAO regulations, but since I have seen this practice at so many airports around the world in so many different countries, I have a hard time accepting that there is not some sort of ICAO regulation governing this type of operation. It is even applied in CDG which also falls under EASA territory. CDG runway centerline separation is less than 400m. CDG does have around 500 m stagger between the touchdown zone and departure runway line up zone.

Quoting PlymSpotter (Reply 2): No. Although the principle has merit, the design/operation envisaged by Tim Leonig is not remotely certifiable according to design regulations (or practical) and therefore could not be built. Using even the very minimum runway/taxiway spacing for parallel runways it would require the demolition of Terminal 5 and reduce the central area to a slither barely 100m wide - leaving no space for a terminal, as this graphic I drew up before demonstrates:

With the exception of some parts of Terminal 5, which are close to the new runways, could you not keep most of the existing terminals and just have a long-ish taxi between terminals and runways? The terminals would be far enough from the runway thresholds that traffic could land or depart over them, no? To the point made in The Economist, you could use electric tugs to tow the airplanes, reducing emissions and wasted fuel.

Quoting PITrules (Reply 36): Considering LGW only has one useable runway, I don't see how it's even a good comparison.

Gatwick demonstrates the maximum capacity you can get out of a runway, double that and you have an approximation of what Heathrow can expect in mixed mode. I believe the NATS study into mixed concluded the same, around 25% increase in capacity.

Quoting PITrules (Reply 36): Lets look at the stated IFR design capacity of LHR vs CDG. 370,000 annual IFR ops at LHR (currently being exceeded by 23%) compared to 680,000 at CDG. The difference of course is that CDG has two additional runways; these are closely spaced parallel runways, yet they increase CDG's IFR capacity by 300,000 over that of LHR. Our discussion at LHR considers one closely spaced parallel runway, so that would be an increase of 150,000 annual movements. Not too shabby, and much greater than what you are alluding to.

It would be, if you could operate two closely spaced IFR parallel runways. But you can't unless they are 760m apart, which is not possible on the footprint of land that we are talking about, so the added capacity is nothing.

Quoting PW100 (Reply 37): On closely spaced parallel runways, you have one runway dedicated for arrivals, and the other dedicated to departures (there are other options, but this is by far the mostly used one). Now you can have the departure aircraft sitting on the departure runway (so not occupying the active arrival runway, and the departure aircraft not interfering with the arrival ILS!) ready to go. As soon as the arrival aircraft is on the ground and committed to stopping, you can have the departure rolling (theoretically even a little sooner, if ATC runway view is not compromised). That departure would be in the air around the same time the landing aircraft clears the arrival runway. By that time in-line horizontal spacing would be sufficient for the next arrival to land.

Not just committed to stopping, exited the active runway. IIRC this was looked at for Manchester, but the response was that they needed 760m of separation to operate this way. So instead they staggered the runways (at much greater cost) and got it down to 390m.

Quoting PW100 (Reply 37): Put a closely spaced parallel runway next to it, and even without any stagger you would be able to virtually double the capacity. The point off course is that all that extra capacity is just departures.

But it has to meet the regulations in order to add any capacity, these state that the minimum separation is 760m unless you have a significant stagger at both ends. Close spacing (i.e. ~300m) is, rightly or wrongly, not an option otherwise under ICAO/CAA regs, so we can consider it all we like, it still won't be certified.

Quoting PW100 (Reply 37): Now I readily admit that I’m not familiar (at all) with ICAO regulations, but since I have seen this practice at so many airports around the world in so many different countries, I have a hard time accepting that there is not some sort of ICAO regulation governing this type of operation.

Oh their manuals and the numerous CAA equivalents make for thrilling bedtime reading.

As I've been saying in this thread, a lot of things are done around the world which either pass/passed local regulations, do not have to adhere to IFR regulations, or have been dispensated for because the layout existed prior to the current regulations taking effect. This results in some amazingly non standard infrastructure compared to today's ICAO standards, but it doesn't mean that they can be used as a precedent for design elsewhere.

Quoting PW100 (Reply 37): It is even applied in CDG which also falls under EASA territory. CDG runway centerline separation is less than 400m. CDG does have around 500 m stagger between the touchdown zone and departure runway line up zone.

France will come under EASA regulation from 2014-2016, when they have finished drafting the EASA aerodrome design standards manual. I believe they are on draft number three and it's still a mass of corrections and red ink. They are based on ICAO standards though, so I don't expect them to differ on runway spacing. If needed (depending on their operation) CDG will receive a dispensation, but in future all new designs will need to conform with EASA/ICAO regulations, so in my view the scope for getting close spaced parallel runways at Heathrow certified under EASA is just as unlikely as the CAA.

Quoting christao17 (Reply 38): With the exception of some parts of Terminal 5, which are close to the new runways, could you not keep most of the existing terminals and just have a long-ish taxi between terminals and runways? The terminals would be far enough from the runway thresholds that traffic could land or depart over them, no?

In the designs Tim Leonig produced, all of T5 would have to go. Not just because it's footprint would be required for the new runways he proposes, but because the associated runway surfaces would require you to lower the height of T5. Terminal 5 is (IIRC) about 40m high, that means the threshold of a runway in it's path would need to be 2km from T5's highest point to clear it as an obstacle.

Quoting christao17 (Reply 38): To the point made in The Economist, you could use electric tugs to tow the airplanes, reducing emissions and wasted fuel.

That I agree with.


Dan  

Quoting PlymSpotter (Reply 29): I'd like to think the CAA would embrace these ASAP in the interests of safety alone. Although in another year it won't be the CAA's place to write the regulations, so I just hope they implement and changes.

Regulation timing has always been problematic (for any number of reasons) and technology will certainly, and increasingly, outpace them. For example, Boeing has equipped aircraft with ADS-B since 2004 and the European mandate for all planes doesn't go into effect for another 2 years. Yet it could have a significant impact in increasing capacity at LHR... even now.

In addition to the previously mentioned NextGen/SESAR and enhanced EVS/SVS HUDS equipage, the noise and environmental impact reduction of the PurePower GTF that is coming on the NEO, CSeries, EJets NG, MHI RJ, etc, would expand nighttime ops at LHR.

With the advent of quieter aircraft, this is some wild speculating on my part that there might exist the possibility of putting a third runway almost within the boundaries of LHR at the east end. This might perhaps be accomplished by extending/shifting the existing 09R/27L runway west and that would free up space for a shorter runway that would roughly align with the old 52/232 runway (but obviously more west/easterly, perhaps ~65/245). And, obviously, several existing "buildings & infrastructure" would have to be moved/demolished.

[Edited 2013-03-30 12:35:25]

Quoting planemaker (Reply 40): Regulation timing has always been problematic (for any number of reasons) and technology will certainly, and increasingly, outpace them. For example, Boeing has equipped aircraft with ADS-B since 2004 and the European mandate for all planes doesn't go into effect for another 2 years. Yet it could have a significant impact in increasing capacity at LHR... even now.

Hopefully the Airports Commission will highlight this kind of benefit.

Quoting planemaker (Reply 40): In addition to the previously mentioned NextGen/SESAR and enhanced EVS/SVS HUDS equipage, the noise and environmental impact reduction of the PurePower GTF that is coming on the NEO, CSeries, EJets NG, MHI RJ, etc, would expand nighttime ops at LHR. With the advent of quieter aircraft, this is some wild speculating on my part that there might exist the possibility of putting a third runway almost within the boundaries of LHR at the east end.

I can't see that set up working at LHR, but I can see the environmental gains heralded by next gen regional jets being of strategic importance to the Northolt proposals. Noise is the big issue there, deal with that and you have the potential to re-open/protect regional routes to Heathrow via a Northolt connection.


Dan  

Quoting PlymSpotter (Reply 41): I can't see that set up working at LHR, but I can see the environmental gains heralded by next gen regional jets being of strategic importance to the Northolt proposals. Noise is the big issue there, deal with that and you have the potential to re-open/protect regional routes to Heathrow via a Northolt connection.

As I said, just speculating but... if 27R was displaced towards the M25 (approx 4,000 ft), it certainly seems that an 8,000 ft third runway constructed roughly parallel with Great South-West Rd could be quite feasible, and preferable to any Northolt proposal for many reasons, especially since ~41% of LHR pax are to/from Europe.

As for noise impact, both PW and CFM claim that the A320NEO will have a 75% reduction on noise footprint. If slightly steeper approaches were approved and implemented, then noise impact would be within airport boundary for the most part.

It sounds like the most CAA approved option would be to add some tracks for Eurostar and move say 25% of takeoffs and landings to CDG. It would only take an extra hour compared to the Tube and allow lots of slack capacity for when weather is bad. In case CDG cannot handle all the load, you can add some flights to BRU.

Quoting PlymSpotter (Reply 39): It would be, if you could operate two closely spaced IFR parallel runways.

Not "would be", but IS. Those are the declared operational IFR capacities for LHR and CDG. As you can see the numbers are much higher for CDG with the use of their close parallel runways.

From page 10 and onward it discusses the planned increases offered by the third then fourth runways at CDG (both of which are close parallel rwys):
http://wwwe.onecert.fr/projets/WakeN...ie_Chevallier_AeroportsdeParis.pdf

Quoting PlymSpotter (Reply 39): so the added capacity is nothing.

Its been shown several times now that it will add capacity, even if it is only a close in runway.

You have yet to show us how these other airports around the world are not compliant with ICAO in how they pair up departing aircraft with arrivals on these close (300m) parallel runways. If you can provide a link which shows ICAO prohibiting these kinds of operations, I would be very interested in reading that.

[Edited 2013-03-31 04:25:32]

Quoting PlymSpotter (Reply 39): France will come under EASA regulation from 2014-2016, when they have finished drafting the EASA aerodrome design standards manual. I believe they are on draft number three and it's still a mass of corrections and red ink. They are based on ICAO standards though, so I don't expect them to differ on runway spacing. If needed (depending on their operation) CDG will receive a dispensation, but in future all new designs will need to conform with EASA/ICAO regulations, so in my view the scope for getting close spaced parallel runways at Heathrow certified under EASA is just as unlikely as the CAA.

The key then would be for the UK to add / commence a project now which would be grandfathered in based on the limitations of LHR before the new regulations take place which will effectively mandate that any increase in air capacity to London be done at a new airport because LHR does not have the physical landmass available.
If I am reading the convo about CAA / ICAO rules and regulations.

Quoting PITrules (Reply 44): Not "would be", but IS. Those are the declared operational IFR capacities for LHR and CDG. As you can see the numbers are much higher for CDG with the use of their close parallel runways.

Quoting PITrules (Reply 44): Its been shown several times now that it will add capacity, even if it is only a close in runway.

OK, just to be clear, I'll try one more time. Such an arrangement could not be certified in the UK, therefore the added capacity is zero - zilch - nothing. What other countries have done is completely regardless.

Quoting PITrules (Reply 44): You have yet to show us how these other airports around the world are not compliant with ICAO in how they pair up departing aircraft with arrivals on these close (300m) parallel runways. If you can provide a link which shows ICAO prohibiting these kinds of operations, I would be very interested in reading that.

I've explained the separation, options for staggering and the potential reasons why other airports/countries may operate such a system several times now. The precedents in the UK are current/proposed parallel runways at MAN, STN and LGW and the regulations are all contained in ICAO manuals. I can't offer a link as I have paper/pdf copies, but I should think they can be found online with little effort. Gatwick is perhaps the most relevant of these precedents actually; BAA proposed a close spaced parallel runway there around twelve years ago, but the result of consultation with the CAA was that it would have to be treated as a single runway due to the spacing. Unsurprisingly the plan now includes adequate spacing, above 760m IIRC.

Quoting par13del (Reply 45): The key then would be for the UK to add / commence a project now which would be grandfathered in based on the limitations of LHR before the new regulations take place which will effectively mandate that any increase in air capacity to London be done at a new airport because LHR does not have the physical landmass available.

The regulations as they are have been in place for at least a decade, so it's much too late for that.


Dan  

Thought it would be interesting for everyone discussing to note the pax breakdown for LHR ( 2011/12 )

Domestic – 6.8%
Europe – 41.0%
North Atlantic – 22.8%
Other long haul – 29.4%

I don't know how many knew that Europe/Domestic pax total almost 48%, which would indicate that well over 65% of LHR air traffic is narrow bodies (see ATC Movements following). This has a whole host of implications from aircraft spacing/runway requirement to noise to pollution, etc, etc.

Air Traffic Movements:

Domestic - 45,130
Europe - 258,880
N. Atlantic - 76,524
Other long haul - 90,807

Aircraft Movements by airline (000)

British Airways - 226.1
Lufthansa - 22.5
BMI - 18.1
Aer Lingus 16.4
Virgin Atlantic - 14.8
Others - 171.0

Additional pax info:

International passengers: 93%
Domestic passengers: 7%
Business travellers: 31.3%
Leisure travellers: 68.7%
Transfer passengers: 34.6%

Pax by airline (000):

British Airways - 31,675
Virgin Atlantic - 3,719
Lufthansa - 2,386
American Airlines - 2,229
Aer Lingus - 2,069
Other - 27,916

Busiest routes:
New York (JFK) - 4.1%
Dubai - 2.7%
Dublin - 2.3%
Frankfurt - 2.1%
Amsterdam - 2.0%

[Edited 2013-03-31 08:43:27]

Quoting PlymSpotter (Reply 46): OK, just to be clear, I'll try one more time. Such an arrangement could not be certified in the UK, therefore the added capacity is zero - zilch - nothing. What other countries have done is completely regardless.

Thank you for taking the time and effort to make things clear. I'm not looking to stir things up, but I still don't quite understand the problems CAA has with these closely spaced parallels?

If I understand correctly, the CAA is perfectly fine with having aircraft landing on a runway next to a closely spaced taxiway (ie. LHR’s current runway-taxiway spacing is around 175 meters) having potentially dozens of aircraft full of passengers? But at the same time they won't allow an aircraft to take-off from a 500 m spaced parallel runway, not even when that landing aircraft is committed to landing, until that landing aircraft has actually vacated said runway? To me that does not make sense.

I could understand that they don't like these operations when visibility is such that ATC can not see both runways (or at least the touch down zone), but even with British weather, that won't be the case for more than 5% of the time, I would think.

PW100

Quoting planemaker (Reply 42): if 27R was displaced towards the M25 (approx 4,000 ft), it certainly seems that an 8,000 ft third runway constructed roughly parallel with Great South-West Rd could be quite feasible

Ooops, instead of 27R I should have stated 09R/27L (southern runway... for absolute clarity!) as I posted earlier...

Quoting planemaker (Reply 40): This might perhaps be accomplished by extending/shifting the existing 09R/27L runway west and that would free up space for a shorter runway that would roughly align with the old 52/232 runway (but obviously more west/easterly, perhaps ~65/245).

Apologies for confusion as my post no. 42 doesn't make any sense otherwise.