Heathrow Eastbound operations criteria

[Opher Ben Peretz 882232]

Hello,

has the old 5 Kt easterly wind component criteria been changed? Most everybody landing 9L with 050/5, let alone on 9R and a Cessna flying VFR without a flight plan3000 feet just NE of the airport. Reminds me that FSP[Mod - Happy Thoughts]engers plays flack hit sound while over Green Park / Buckingham Palace above 3000 on the BNN turn to 27.

[Anthony Lawrence]

Hello,

has the old 5 Kt easterly wind component criteria been changed? Most everybody landing 9L with 050/5, let alone on 9R and a Cessna flying VFR without a flight plan3000 feet just NE of the airport. Reminds me that FSP[Mod - Happy Thoughts]engers plays flack hit sound while over Green Park / Buckingham Palace above 3000 on the BNN turn to 27.

 

 

If the winds favour 09's then you always land 09L, depart runway 09R.

 

Regards,

A...

[Opher Ben Peretz 882232]

Thanks for your answer Anthony, however it is incompliant with my memory of airport procedures and the following current real world account:

http://www.heathrowairport.com/portal/page/HeathrowNoise%5ENoise+explained%5ECauses+of+aircraft+noise%5EUnder+the+flight+path/a817f847de609010VgnVCM10000036821c0a____/448c6a4c7f1b0010VgnVCM200000357e120a____/

 

Can you please answer this, thanks.

 

 

Hello,

has the old 5 Kt easterly wind component criteria been changed? Most everybody landing 9L with 050/5, let alone on 9R and a Cessna flying VFR without a flight plan3000 feet just NE of the airport. Reminds me that FSP[Mod - Happy Thoughts]engers plays flack hit sound while over Green Park / Buckingham Palace above 3000 on the BNN turn to 27.

 

 

If the winds favour 09's then you always land 09L, depart runway 09R.

 

Regards,

A...

[Anthony Lawrence]

I'm not sure which part is incompliant - it states that if the wind is 5knots or more, and it favours 09s, then thats what they'll use... ?

 

 

Regards,

A....

[Phillip Speer]

I think the improtant part here is if the winds "favour" easterlies. Looking at the current Heathrow METAR the surface winds are calm and the TAf is not that dramatic either but looking at the 3000ft winds there is a 30knot headwind from 080 showing that the winds "favour" easterlies. Now if the surface winds were 060/03 but the TAF and other winds were from the west or even the south then the winds would "favour" westerlies. It's all about looking at a general trend and not a spot METAR.

 

Phillip

 

edit: METAR just updated and winds now 050/08

[Robbie Garrett]

Heathrow Has been on 09's for a good month now Real world.

 

Kind of fun and it aint going to change either.

 

Sunday

 

Sunrise 04:57 (BST)

Sunset 20:59 (BST)

Sunday's predominant weather is forecast to be light rain.

 

15°C

 

12°C

 

Sunday's wind direction: North Easterly Wind.17

poor 1011 81

Sunday's UV index risk: 1.

 

Sunday's atmospheric pollution: Moderate.

Monday

 

Sunrise 04:56 (BST)

Sunset 21:01 (BST)

Monday's predominant weather is forecast to be heavy rain.

 

17°C

 

12°C

 

Monday's wind direction: North Easterly Wind.17

moderate 1011 92

Monday's UV index risk: 1.

 

Monday's atmospheric pollution: Moderate.

Tuesday

 

Sunrise 04:55 (BST)

Sunset 21:02 (BST)

Tuesday's predominant weather is forecast to be light rain.

 

20°C

 

14°C

 

Tuesday's wind direction: North Easterly Wind.7

moderate 1011 75

Tuesday's UV index risk: 2.

 

Tuesday's atmospheric pollution: Moderate.

Wednesday

 

Sunrise 04:54 (BST)

Sunset 21:03 (BST)

Wednesday's predominant weather is forecast to be heavy showers.

 

22°C

 

13°C

 

Wednesday's wind direction: East South Easterly Wind.9

good 1004 53

Wednesday's UV index risk: 6.

 

Wednesday's atmospheric pollution: Moderate.

Thursday

 

Sunrise 04:53 (BST)

Sunset 21:04 (BST)

Thursday's predominant weather is forecast to be heavy showers.

 

22°C

 

11°C

 

Thursday's wind direction: South Westerly Wind. 10

 

 

I have not got a clue but 1 hour ago when i was flying the Project Opensky 757 Project Openskies (BA) Livery.

 

I saw two take off from 27R becuase the VATSIM-UK Forum says so.

 

Winds at 070 (050) at 17mph is not going to make 27's in use.

 

I been flying into and out of Heathrow and some ask me what runways in use. They say why is people using 09's when on the forum it says 27s are in use and the Runway change at 15:00L.

 

I have lived under the 27R ILS for 15 years so i know when what runway is in use. The amount of traffic and the timings explains it all as a Spectator under the ILS.

 

 

IF it says 27's are in use that does not mean they are in use. It's just put there as it's a timetable of which runway is in use at which time when 27's are active.

 

 

Robbie

[Opher Ben Peretz 882232]

"Wind favours..." without specific mention of other factors I understand as any easterly wind, regardless of magnitude. This apparently is contra to my understanding of the procedure.

The whole issue dating back to 1965 is dense residential area noise abatement. Actually the closure of runway 9L for departures dates even earlier to the fifties. The "above 5 knots" switchover is there to protect aircraft, wheras all the rest is opposite- to protect residents.

This is one more reason why a) forecast and b) wind at 3000 feet for determining active runway, are irrelevant. The first one being aviation principles as I understand them.

 

 

I think the improtant part here is if the winds "favour" easterlies. Looking at the current Heathrow METAR the surface winds are calm and the TAf is not that dramatic either but looking at the 3000ft winds there is a 30knot headwind from 080 showing that the winds "favour" easterlies. Now if the surface winds were 060/03 but the TAF and other winds were from the west or even the south then the winds would "favour" westerlies. It's all about looking at a general trend and not a spot METAR.

 

Phillip

 

edit: METAR just updated and winds now 050/08

[Sean Reedman]

Opher - the switch due to noise only happens on 27's = it's been pretty well explained why they favour easterlies - landing 09L does not take them directky over Windsor Castle whereas landing 09R would - there may be times they do use 09R but very rarely.

 

Not sure what else you are after ?

[Aggrey Ellis 964561]

Heathrow director gave me 9R today because I was going to terminal 4.

[Anthony Lawrence]

Heathrow director gave me 9R today because I was going to terminal 4.

 

 

Is that the only reason he gave you 09R?

Just seems a strange reason that's all...

 

Regards,

A...

[Aggrey Ellis 964561]

Heathrow director gave me 9R today because I was going to terminal 4.

 

 

Is that the only reason he gave you 09R?

Just seems a strange reason that's all...

 

Regards,

A...

 

I was originally heading for 09L but he asked me if I was going to Terminal 4 and I replied yes and he set me up for that. I think there was another plane at the time either landing or taking off 9L.

[Opher Ben Peretz 882232]

I approached Heathrow yesterday around 1000 GMT, wind 050/5. Tower came online and specified 9L for approach.

In my second post above I provided a link to real world data regarding noise abatement and runway selection, let me quote:

"Heathrow and the ‘westerly preference’

But at Heathrow, the wind is not the only factor that governs how planes take off. There are also rules and agreements to take account of people as well as nature. So that planes don’t take off over central London every time the wind comes from the east (which in some years can be as much as half the time), Government policy is that planes should always take off to the west, towards Windsor, unless the wind is too strong. This policy, with a few changes, has been in place at Heathrow since 1962. A relatively new element of this is that late at night there is a ‘westerly preference’ (a preference for taking off towards the west) one week, and an easterly preference the next. This is so the burden of the noise of planes at night is shared more fairly between communities to the east and to the west of Heathrow.

So, at Heathrow all flights take off into the west, unless there is an easterly wind of 5 knots or more."

 

 

As I read it, these two do not live well together, regulation and actual ATC, this is what I want to understand. I haven't seen a reply which answered my question.

 

 

 

Opher - the switch due to noise only happens on 27's = it's been pretty well explained why they favour easterlies - landing 09L does not take them directky over Windsor Castle whereas landing 09R would - there may be times they do use 09R but very rarely.

 

Not sure what else you are after ?

[Anthony Lawrence]

I approached Heathrow yesterday around 1000 GMT, wind 050/5. Tower came online and specified 9L for approach.

 

Ok so the surface winds there favour 09s, and since you don't land 09R it'd be 09L, in my opinion the controller did right.

 

In my second post above I provided a link to real world data regarding noise abatement and runway selection, let me quote:

"Heathrow and the ‘westerly preference’

But at Heathrow, the wind is not the only factor that governs how planes take off. There are also rules and agreements to take account of people as well as nature. So that planes don’t take off over central London every time the wind comes from the east (which in some years can be as much as half the time), Government policy is that planes should always take off to the west, towards Windsor, unless the wind is too strong.

 

The important thing here is "unless the winds are too strong" - as phillip said earlier, you cannot soley base this on surface wind - look at the wind higher up instead of just the SURFACE wind.

 

The westerly preference is:

27L and 27R will normally be used in preference to 09L and 09R when the tailwind component is no greater than 5kts and the surface is dry.

 

This policy, with a few changes, has been in place at Heathrow since 1962. A relatively new element of this is that late at night there is a ‘westerly preference’ (a preference for taking off towards the west) one week, and an easterly preference the next. This is so the burden of the noise of planes at night is shared more fairly between communities to the east and to the west of Heathrow.

So, at Heathrow all flights take off into the west, unless there is an easterly wind of 5 knots or more."

 

Firstly, you approached LHR at 1000zulu - which is 10AM, therefore the night thing makes no difference to your approach - and secondly, you've answered your own question? If the wind is 5knots or more then it will dictate the runway in use.....

 

As I read it, these two do not live well together, regulation and actual ATC, this is what I want to understand. I haven't seen a reply which answered my question.

 

I'm with Sean on this one, I'm really not sure at what you are after here. The article you gave us details all the preferential stuff - and we've clarified it here...

 

Regards,

A...

[Michael Benson]

Ok so the surface winds there favour 09s, and since you don't land 09R it'd be 09L, in my opinion the controller did right.

 

ATC can land aircraft on 09R. The usual reasons are operational (e.g. an aircraft going to T4) or when TEAMing.

 

Firstly, you approached LHR at 1000zulu - which is 10AM

 

To be pedantic - at the moment 10Z is actually 11 Local. All the noise rules and regulations are based on local time as the local inhabitents tend not to operate on UTC!

[Opher Ben Peretz 882232]

It is simple. The determining factor is the runway tail wind component, not wind velocity.

 

The important thing here is "unless the winds are too strong" - as phillip said earlier, you cannot soley base this on surface wind - look at the wind higher up instead of just the SURFACE wind.

being 5 knots or more, not wind velocity.

Can someone explain how wind at altitude has any relation to the direction of traffic and duty runway selection? To me there is none.

 

I didn't raise as issue any late night operations, just brought the complete paragraph to your attention. The advantage is that now you know the whole story.

[Kayleigh Young 1060779]

Can someone explain how wind at altitude has any relation to the direction of traffic and duty runway selection? To me there is none.

 

Hello Opher,

 

Take hypothetically the SFC wind at Heathrow is 270 at 5kts and the wind at 1k is 090 at 15, 2k its 090 at 25 and 5k its 090 at 30 It is generally elected that Heathrow will be on easterlies, although some will say it's not a huge deal which way we swing it because essentially the wind will not effect the landing performance of anything that is allowed to fly into Heathrow it can effect the aircrafts climb performance. It could also be noted that the wind at SFC level may swing around in favor of the wind at altitude.

[Opher Ben Peretz 882232]

Thanks Kayleigh,

a. At my flight academy we learnt when I started flying in 1963, that such wind swing doesn't exist in our atmosphere. Its changes are much more gradual in both direction and magnitude. 10 degree direction and 5 knot magnitude per 1000 feet change is more like it in meaningful weather at low altitude.

b. At test pilot school where I mastered in 1975 among other things aircraft performance, there was never mention that winds affect climb performance (the term refers to rate of climb). It could affect climb gradient, but how is that relevant in the magnitude of real world wind swing and relevant low altitudes?

BTW how does the tower determine current winds at these altitudes?

Can someone explain how wind at altitude has any relation to the direction of traffic and duty runway selection? To me there is none.

 

Hello Opher,

 

Take hypothetically the SFC wind at Heathrow is 270 at 5kts and the wind at 1k is 090 at 15, 2k its 090 at 25 and 5k its 090 at 30 It is generally elected that Heathrow will be on easterlies, although some will say it's not a huge deal which way we swing it because essentially the wind will not effect the landing performance of anything that is allowed to fly into Heathrow it can effect the aircrafts climb performance. It could also be noted that the wind at SFC level may swing around in favor of the wind at altitude.

Edited May 26, 2008 at 05:28 PM by Guest

[Kayleigh Young 1060779]

All I can tell you Opher is what I have been taught, climb gradient was what I was referring to and a relationship between low level wind and surface wind does exist to some extent.

[David Winters 905945]

As others have already pointed out, choice of runway is not just based on current surface wind direction. Other factors such as predicted wind later in the day as well as upper level winds are also taken into consideration.

 

For example, the surface wind may be 360@5 which would favour according to the rules 27s. However, if the predicted winds say that later on in the day the wind will swing round to say 070@10 then ATC may opt to start off using 09s to avoid a switch over during busy periods. This is particularly the case if the surface wind is set to vary regularly over the course of a day.

 

While Kayleighs example was a little extreme, the general principle is correct. A significant tailwind on approach or climbout would cause more problems than a small tailwind on landing/take off.

 

Hope this helps

[Kayleigh Young 1060779]

While Kayleighs example was a little extreme, the general principle is correct. A significant tailwind on approach or climbout would cause more problems than a small tailwind on landing/take off.

 

Hope this helps

 

So he says

[Opher Ben Peretz 882232]

While Kayleighs example was a little extreme, the general principle is correct. A significant tailwind on approach or climbout would cause more problems than a small tailwind on landing/take off.

Hope this helps

 

So he says

This situation doesn't exist in our atmosphere. Even if it did, how can it cause anything?

[David Winters 905945]

Ok another example.

 

Surface wind 050@5

 

2000ft wind 060@15

 

Now this is quite possible. Looking at the surface wind information only 27s would be in use. However, when th upper winds come into play obviously 09s are preffered in this example.

 

Now this is the current real world situation:

 

Surface wind 340@4

2000ft wind 110@10

 

09s are currently in use

[Opher Ben Peretz 882232]

How does the tower controller know the wind at altitude in the VATSIM atmosphere?

How does this current data aid runway 9R westbound departures (CPT, MAY, MID, Southhampton) which I [Mod - Happy Thoughts]ume are near 50% of departing traffic? How does it help approaching aircraft?

 

Ok another example.

 

Surface wind 050@5

 

2000ft wind 060@15

 

Now this is quite possible. Looking at the surface wind information only 27s would be in use. However, when th upper winds come into play obviously 09s are preffered in this example.

 

Now this is the current real world situation:

 

Surface wind 340@4

2000ft wind 110@10

 

09s are currently in use

[David Winters 905945]

Ok well upper wind information in the UK can be found on the met office website. However, as far as I know, this information is not accurately depicted by the pilot clients. This said, controllers may check this information to be as realistic as possible.

 

The choice of runway has nothing to do with aiding certain departures (if I've understood you correctly). It is all to do with aircraft performance in the initial climb.

 

With regard to how the data suits arriving aircraft, a quick google search comes up with this:

 

History tells us that tailwind is especially dangerous during the approach and landing. When an approach is made with tailwind, the rate of descent has to increase to maintain the glide slope relative to the ground. With a constant approach speed, the engine thrust must decrease with increasing tailwind to maintain glide slope. In high tailwind conditions, the engine thrust may become as low as flight idle. Flight idle thrust during the approach is undesirable for jet aircraft because engine response to throttle input is slow in this condition, which can be a problem when conducting a go-around. It can also become difficult to reduce to final approach speed and to configure the aircraft in the landing configuration without exceeding flap placard speeds.

 

So, a small tailwind on landing, is preferabe to a large tailwind on approach. Of course, if the tailwind at surface level is signifcant enough as well, the alternative runway sould be used.

[Opher Ben Peretz 882232]

Ok well upper wind information in the UK can be found on the met office website. However, as far as I know, this information is not accurately depicted by the pilot clients. This said, controllers may check this information to be as realistic as possible.

 

VATSIM weather is to my understanding not synchronized with current real world conditions but rather delayed, about one hour.

 

The choice of runway has nothing to do with aiding certain departures (if I've understood you correctly). It is all to do with aircraft performance in the initial climb.

 

Both parts of what you show as contradicting are essentially the same thing. If the choice of actual runway selection is dependent on wind at altitudes like 2000 and 3000, they affect both departure and approach flying conditions. Careful analysis of both flight phases indicates the following: a. During departure while traversing these altitudes, 50% of the headings flown are with a tail wind component regardless of runway selection. While climb gradients are affected, the resultant wind effect is about symmetrical so no gain whatsoever is achieved. b. During approach ground speeds and rates of descent while traversing these altitudes are affected. Having 10-15 knot higher ground speed at 2000-3000 feet has no impact on aircraft or pilot performance, handling and safety, since the wind velocity gradually reduces along the approach.

 

With regard to how the data suits arriving aircraft, a quick google search comes up with this:

 

History tells us that tailwind is especially dangerous during the approach and landing. When an approach is made with tailwind, the rate of descent has to increase to maintain the glide slope relative to the ground. With a constant approach speed, the engine thrust must decrease with increasing tailwind to maintain glide slope. In high tailwind conditions, the engine thrust may become as low as flight idle. Flight idle thrust during the approach is undesirable for jet aircraft because engine response to throttle input is slow in this condition, which can be a problem when conducting a go-around. It can also become difficult to reduce to final approach speed and to configure the aircraft in the landing configuration without exceeding flap placard speeds.

 

So, a small tailwind on landing, is preferabe to a large tailwind on approach. Of course, if the tailwind at surface level is signifcant enough as well, the alternative runway sould be used.

I intended to have a professional discussion, but this clipped information and commentary is closer to myth than science, IMO. It is essentially unfounded, except as general statement, and doesn't properly address the issue I raised scientifically.

Thanks anyway.