Bristol Airport - Filton

[Pacific231G]

21 hours ago, pwilson said:

This is certainly an interesting discussion I've provoked.  Looking again at the map and going into pure hypotheticals, if an airport station - "Bristol International" was to be built, would situating the station on the Stoke Gifford / Avonmouth line even work?

 

 

 

21 hours ago, pwilson said:

 

The General Aviation terminal at Filton was South East of the Eastern end of the main runway and next to the A38 fence with AFAIR a short walk to the security gate leading out onto the road  (and local buses) It was though close to your suggested airpiort station. It  had a fairly small aircraft apron with a very wide taxiway with a very shallow curve that "became" the end of the runway 

The "terminal" was though at the "Portakabin with a coffee machine and a desk to pay your landing fee"  end of aiport terminal design though I think there'd once also been a flying school there.

The better positioning of Filton was made clear to me by being able to catch a local bus into Bristol for lunch and it didn't take that long.  

 

Had Filton developed into a regonal airport it would have needed far better terminal facilities with a far larger apron probably further back from the runway but Gatwick developed with its original main terminal at one end of the runway so it's not an impossible location. That would have made the Avonmouth line the most accessible  in terms of railways but I think a station on the Cardiff line - Parkway with a people mover- would have made far more sense.  For a model though a small station on or spurred off the Avonmouth line with a shuttle service to Bristol TM and maybe Parkway might make sense. Bristol (Filton) could easily have become as large as Stansted and if it also handled mail.....

 

Of course, being Bristol, if you wanted to honour IKB there is a modern "Aeromovel" atmospheric railway at Salgado Filho International Airport connecting its terminal to the Porto Allegre metro in Brazil.   I think it;s suck and blow rather than just suck but it's the same principal though now using a modern rubber seal for the slot.

Edited August 17, 2020 by Pacific231G

[rob D2]

On 15/08/2020 at 17:37, Pacific231G said:

It's really landings that cause the problem over a larger area as airliners are at relatively high power over a long shallow (typically 3 degree) ILS glidepath all on the same line  whereas on take off, though at full power, they climb fairly quickly (even before crossing the perimeter fence)  and peel off in various directions. If you know the London suburbs on the 26 approaches to Heathrow the  aircraft noise over north Richmond is almost constant whereas when the wind is easterly you're just not that aware of them. You're right about direction though. I don't think even Brentford suffers that much from Heathrow.

Not true. 
airliners fly CDA - constant descent approaches to the ILS and then maintain minimum drag as long as possible  (1000’)so not too noisy TBH.

 

airliners rarely fly “ full power” departures , the engines are “ derated “ using various electronic means to ensure they are normally at about 75%.

Edited August 18, 2020 by rob D2

[The Johnster]

Atmospheric Railways suck...

[37114]

My parents lived less than 1 mile from Lulsgate until I was 10. They attended a public meeting with local officials in the mid 1970s when the extension of the runway was being floated (even at this stage Lulsgate was still tiny) and my dad asked the reasonable question as why was Lulsgate being considered for extension when Filton had a long runway, was better located etc. The meeting chair put his pen down sat back in his chair and basically said that it was 15 to 20 years to late to consider Filton due to the proximity of housing and politely asked all future questions be focussed on Lulsgate. Shame really as my ex home city is all the worse for it and seems to continually manage to make abysmal transport planning decisions to this day.

[PMP]

The other big reason Filton wasn’t chosen is the topography either side of the runway, and the A38. The runway looking west is uphill, and in a valley. ATC couldn’t see the western threshold and had a CCTV camera to monitor it due to the infamous ‘hump’. The costs associated with the moving of the A38 (which would have been needed) were stratospheric. 
 

Lulsgate had invested in infrastructure which meant that would always be a better and more cost effective option, particularly today with CAT3 capability and the improvements in aircraft performance. 
 

As far as noise goes departing traffic is the biggest problem. As @rob D2 mentions CDA approaches are making healthy inroads into minimising disruption from approaching traffic, departures will always be the biggest problem. 
 

Cardiff unfortunately won’t be a player in significant airport development and traffic growth. The market is simply too small, and always was. The M4 corridor allows the relatively quick access into Bristol, London and Birmingham for air travel. Whilst that might seem odd, it’s the same reason East Midlands hasn’t  developed passenger traffic like The London Airports, the passengers, drive to London. It has however done very well for night cargo operations, due to its central location and easy access to major road networks.

Edited August 18, 2020 by PMP

[The Johnster]

Exactly, Rhoose is a lame duck except as a local airport, but the M4 corridor does not make it easy for South Walians to access Lulsgate as you have to come off the M5 at Avonmouth and negotiate the Cumberland Basin County Fair Dodgems, then thread your way slowly along a one lane each way road through the southwestern 'burbs of Bristol until you get the the airport.  Alternative is to plug on down the M5 towards Exeter, risking the Avonmouth Bridge tailback, and come off at WSM, having been treated to a grandstand view of a/c taking off or landing only a mile off the M/way at the western end of Lulsgate runway, and then thread your way back through the country lanes, a taste of Zummerzet at it's most bucolic, which is pretty bucolic if you're late for your check in.

 

Birmingham or Heathrow are better choices than Lulsgate for South Walians. and Gatport Airwick or East Midlands about the same.  My advice to any South Walian trying to fly from Stanstead is, really, seriously dude, just don't!!!

Edited August 18, 2020 by The Johnster

[PMP]

13 minutes ago, The Johnster said:

Exactly, Rhoose is a lame duck except as a local airport, but the M4 corridor does not make it easy for South Walians to access Lulsgate as you have to come off the M5 at Avonmouth and negotiate the Cumberland Basin County Fair Dodgems, then thread your way slowly along a one lane each way road through the southwestern 'burbs of Bristol until you get the the airport.  

 
Clearly not actually done it then...

M4 M49 A4 A370 A38. That’s from Duffryn Newport, allow 1hr10mins. 

 

[The Johnster]

Actually done it then.

 

Dyffryn Newport is about as close as you can get to the bridge; I need another 20 mins from the Newport side of Cardiff in clear traffic, and anyone from Pontypridd, or Swansea, is probably better heading for Birmingham via A40/M50/M5/M42

 

2005 landed Lulsgate from Belfast 16.40, picked up hired minibus for group about 17.10.  A370/A4 Portway/M5/M42/M4 to drop off point Sophia Gardens (dropped 3 Newport members at Celtic Manor, for Dyffryn, in McDonald's car park 20.30), arrive Sophia Gardens 21.20.  Sunday evening, traffic, fog on M/ways but bridge and M4 clear Welsh side.  Give me Birmingham over that any day; no traffic once you clear the M5 and a more pleasant run, no urban traffic at all.  Outward journey start Sophia Gardens 0500 for 09.30 check in Lulsgate (there 07.30) for 10.30 take off.  A flight from Rhoose left 10 mins later and arrived 5 mins later; on the return journey a Belfast-Rhoose flight left  3 hour later, 18.50 and arrived Rhoose 50 mins later; would have had us at Sophia Gardens 20 mins earlier.  

 

Lulsgate was chosen by the group's treasurer, nomally pretty hot on this sort of thing, Easy Jet over BMIbaby from Rhoose, because flights were £35 cheaper per person, call it £15 after we'd hired the minibus and driver.  £15 pound for hours of minibus hell, getting up at 04.00 when a Rhoose departure at 10.35 would have meant another 2 hours in bed not landing in Belfast exhuasted and wasting a day, and just a load of faff; somebody could have easily gone out and picked up the Dyffryn girls.  Never again.  If I can't fly from Rhoose, then by and large I don't fly, but if needs must Birmingham or Heathrow over Lulsgate any day.  In fact, I don't fly from Lulsgate, ever, though have called there on a Flybe from Newquay, great way to take a bicycle to Cornwall, shame they've gone under. 

 

Incidentally, used my WAG bus pass as ID for security throughout this trip, expecting trouble.  Got none, fair play security Lulsgate and Aldergrove both ways.

[The Johnster]

BTW, Cornwall is WAY too hilly for bicycles...

[PMP]

2 minutes ago, The Johnster said:

If I can't fly from Rhoose, then by and large I don't fly, but if needs must Birmingham or Heathrow over Lulsgate any day.  

Time clearly not a factor then. 

[Legend]

1 hour ago, PMP said:

 
Clearly not actually done it then...

M4 M49 A4 A370 A38. That’s from Duffryn Newport, allow 1hr10mins. 

 

I’ve done it too , from Swansea and as you say it can be relatively fast , but equally it can be very slow and, of course if you are catching a plane you have to allow a reliable time to catch it .  Pinch points are around M5 which can slow down M49 . I have a feeling that when M5 is clogged Traffic comes off into surrounding roads .  Then you have slow speed through Avon Gorge . Plenty of time to admire the scenery , then that final three miles on the A38 . Sorry but the road system is far from fit for an airport .  In the summer in particular it can be chaotic .  Don’t get me started on the relocation of the car hire facilities necessitating a bus journey to the terminal, adding a further 20-30 mins.  If there is a plus point of Covid it’s that I haven’t had to do this journey since early March .  If there were flights by a reliable airline from Cardiff I’d certainly consider it . 

Edited August 18, 2020 by Legend

[PMP]

16 minutes ago, Legend said:

I’ve done it too , from Swansea and as you say it can be relatively fast , but equally it can be very slow and, of course if you are catching a plane you have to allow a reliable time to catch it .  

And that’s it in a nutshell. Obviously times will vary and BRS’ road access isn’t ideal. However compared to trying to get from Swansea to Heathrow or Brum involves a far greater distance and travel time, as well as local arrival ‘restrictions’ M4 Reading to M25 and M5 to M42 respectively. So BRS wins hands down for South/West Wales every time as far as simple connectivity and market access goes. Recent pax figures BRS 8m, CWL 1.2m per year.
 

As far as the OP goes rule 1 applies. The only thing to bear in mind is that the traffic will be 100% passenger into the terminal area. You could maybe (rule1) add fuel inbound, but that would be kept well away from the terminal area for obvious safety reasons.

Edited August 18, 2020 by PMP

[Pacific231G]

3 hours ago, rob D2 said:

Not true. 
airliners fly CDA - constant descent approaches to the ILS and then maintain minimum drag as long as possible  (1000’)so not too noisy TBH.

 

airliners rarely fly “ full power” departures , the engines are “ derated “ using various electronic means to ensure they are normally at about 75%.

Depends how you define too noisy. Try sitting in the Old Deer Park in Richmond when Heathrow is on 27L. By that stage (five NM from the threshold so, on Heathrow's three degree ILS approach, about 1500ft) aircraft normally have wheels down and flaps 3 (since I don't fly airliners into Heathrow I checked with the A320 procedures and the minimum height to start flap deployment is 2000) so they're fairly draggy.   I don't know the range of thrusts typically used during an airliner's approach but I do know how much noise they make at 1500ft. 

You're right about jet airliners using derated or reduced power departures as it saves maintenance and increases engine life *. The actual percentage used depends on umpteen factors. More power is used on departure and so more noise  but it is more localised. On approach the aircraft is at lower power (but not that low ) but closer to the ground for longer so there is a balance of nuisance.

 

Who was the genius who thought that building London's main airport on the western edge of the conurbation with a prevailing westerly wind was a great idea? 

 

(* Piston engine aircraft almost invariably use full power for take off so that's what I'm used to)

 

Edited August 18, 2020 by Pacific231G

[PMP]

21 minutes ago, Pacific231G said:

Depends how you define too noisy. 

That’s really easy, noise is ‘unwanted’ sound. People’s subjectivity to the source is the key. Jazz at any volume to me is noise. Departure noise is the biggest disruption and will remain so statistics/complaints and noise measurements prove this time after time.

Arrival noise is predominantly airframe rather than engine generated, and whilst work is ongoing to reduce it, only so much can be done. Arrival noise had gained a higher profile of late due to departures being so much quieter than in the past. Stabilised approaches are required so from about 5nm miles out (1500ft) the aircraft is normally at a fixed altitude and speed. On a CDA you minimise power increases, simply put you don’t want to accelerate downhill. Again that is unlikely to change in the foreseeable future. This gives a concentration of traffic on the approach path from roughly ten (NM) from the airport. Again unlikely to change anytime soon. 

Edited August 18, 2020 by PMP

[The Johnster]

3 hours ago, PMP said:

Time clearly not a factor then. 

It is, but in a holistic way.  Rhoose had the advantage on the Belfast trip I mentioned of being a later departure from home, and an earlier arrival back at home, with a much shorter cramped minibus journey and less stress.  Time isn't everything, neither is money; I would have more than willingly stumped up the extra £!5 and made my own way to Rhoose (as mentioned, I had and still have a Welsh Assembly Govt bus pass).  I am in any case unlikely to be doing a lot of air travel in my dotage; can't afford it!   Had I known what was in store I'd have made my own way to Belfast from Rhoose and met up with the group there.

 

2 hours ago, Pacific231G said:

 

Who was the genius who thought that building London's main airport on the western edge of the conurbation with a prevailing westerly wind was a great idea?

This was in the days when the premium Eastern Seaboard flights, New York and Washington, had to land at Shannon and Gander to refuel, until the introduction of the Boeing Stratocruiser, which could make Idlewild from Heathrow without refuelling, just, in about 16 hours.  Fuel was critical on the Transatlantic routes, the 1,800 miles Great Circle Shannon-Gander being as much as the aircraft of the day could safely undertake.  Positioning the airport to the east of London would have compromised the range by about 30 miles.  Of course, the distances on the European and 'Empire' routes would have been the same or less, but there plenty of places on mainland Europe to put down for fuel, but not so many over the North Atlantic; Rekyavik, quite often weatherbound in those days, and that's it.

[PMP]

Heathrow’s position had nothing to do with Transatlantic commercial flights.

 

Heathrow was The Fairy Aviation companies test and development airfield, and was a fighter satellite airfield for RAF Northolt. Towards the end of the war it was transferred to RAF Transport command to allow regular flights to the Far East and the Government bought the site which had a significant amount of land. VJ meant the requirement to get supplies quickly to that theatre of operations rapidly evaporated.
 

The east of London wasn’t/isn’t an option because ‘London’ is in the way for access, not to mention no suitable sites.

[Pacific231G]

12 hours ago, PMP said:

That’s really easy, noise is ‘unwanted’ sound. People’s subjectivity to the source is the key. Jazz at any volume to me is noise. Departure noise is the biggest disruption and will remain so statistics/complaints and noise measurements prove this time after time.

Arrival noise is predominantly airframe rather than engine generated, and whilst work is ongoing to reduce it, only so much can be done. Arrival noise had gained a higher profile of late due to departures being so much quieter than in the past. Stabilised approaches are required so from about 5nm miles out (1500ft) the aircraft is normally at a fixed altitude and speed. On a CDA you minimise power increases, simply put you don’t want to accelerate downhill. Again that is unlikely to change in the foreseeable future. This gives a concentration of traffic on the approach path from roughly ten (NM) from the airport. Again unlikely to change anytime soon. 

Ummm. If the aircraft was at a fixed altitude (though one normally refers to height above the runway as in 'circuit height' )  it would never land. I'm sure you meant a fixed rate of descent. 

 

Once it joins the ILS glideslope (or even on a visual approach) an airliner will be descending at 3 degrees (at most airports) There will be increases in engine power as flaps and gear are extended to maintain the appropriate  approach speed. I'm pretty sure it's in the phase of approach before joining the glideslope that a CDA approach improves on noise levels over the former step down approach. That improves the situation for a far larger population than the glideslope and initital climbout but at a relatively low intensity,  its people living out to about 6-7miles who experience high levels of aircraft noise. 

The noise contours for Gatwich are interesting

https://www.gatwickairport.com/globalassets/publicationfiles/business_and_community/all_public_publications/aircraft_noise/lgw_2018_annual_contours_report_final.pdf

 

Westerly approaches and departures were naturally predominant but, though the contour was more concentrated on the western side, the area affected was somewhat greater on the eastern side. 

 

I've landed at airfields with VASI - the red and green lights that tell you whether you're above, below or on the glideslope- and those approaches- one of them was to Filton-  felt very odd requiring far more power than I'd normally use.   If you look at the approach to Heathrow from the other side of the aerodrome in more normal times than now you'll see a line of aircraft all  on exactly the same line and passing over exactly the same streets and houses. 

[rob D2]

2 hours ago, Pacific231G said:

Ummm. If the aircraft was at a fixed altitude (though one normally refers to height above the runway as in 'circuit height' )  it would never land. I'm sure you meant a fixed rate of descent. 

 

Once it joins the ILS glideslope (or even on a visual approach) an airliner will be descending at 3 degrees (at most airports) There will be increases in engine power as flaps and gear are extended to maintain the appropriate  approach speed. I'm pretty sure it's in the phase of approach before joining the glideslope that a CDA approach improves on noise levels over the former step down approach. That improves the situation for a far larger population than the glideslope and initital climbout but at a relatively low intensity,  its people living out to about 6-7miles who experience high levels of aircraft noise. 

The noise contours for Gatwich are interesting

https://www.gatwickairport.com/globalassets/publicationfiles/business_and_community/all_public_publications/aircraft_noise/lgw_2018_annual_contours_report_final.pdf

 

Westerly approaches and departures were naturally predominant but, though the contour was more concentrated on the western side, the area affected was somewhat greater on the eastern side. 

 

I've landed at airfields with VASI - the red and green lights that tell you whether you're above, below or on the glideslope- and those approaches- one of them was to Filton-  felt very odd requiring far more power than I'd normally use.   If you look at the approach to Heathrow from the other side of the aerodrome in more normal times than now you'll see a line of aircraft all  on exactly the same line and passing over exactly the same streets and houses. 

Hmmm. 

 

VASIs are red and white, no green , and aligned with the TDZ. No extra power required As they are also 3 degrees, Largely disappeared to be replaced with PAPIs.

 

By fixed height ( and no we’d don’t refer to height above the airfield, normally AMSL).

 

Rate of descent VARIES, Because we start at a higher speed , you need higher ROD to stay on the GS, that then reduces to maintain the glideslope.

 

How do I know all this ? Because I actually do it.

[KeithMacdonald]

On 15/08/2020 at 10:57, jonny777 said:

 

A Welsh national airline? Do you mean like Air Cymru? 

 

I think they stretched to 7 aircraft at their peak, but then called in the receivers. 

 

 

They did at least have a better fleet than Yorkshire Airlines.

[Pacific231G]

1 hour ago, rob D2 said:

Hmmm. 

 

VASIs are red and white, no green , and aligned with the TDZ. No extra power required As they are also 3 degrees, Largely disappeared to be replaced with PAPIs.

 

By fixed height ( and no we’d don’t refer to height above the airfield, normally AMSL).

 

Rate of descent VARIES, Because we start at a higher speed , you need higher ROD to stay on the GS, that then reduces to maintain the glideslope.

 

How do I know all this ? Because I actually do it.

Indeed red and white. It's a long time since I've used them and checking back yes  they were PAPIs. They used to have them at Bembridge when it was still BNB's aerodrome but none of the airfields I regularly use has them. I think Kemble does but I've not been there for a few years. You're in Swindon so do you fly there, commercially or with the military?

You surely do need more power for a 3 degree approach than a 6 degree one and I always thought the term "glide slope" was a misnomer. 

 

Edited August 19, 2020 by Pacific231G

[rob D2]

14 minutes ago, Pacific231G said:

Indeed red and white. It's a long time since I've used either. They used to have them at Bembridge when it was still BNB's aerodrome- but none of those I regularly use has them. I think Kemble does but I've not been there for a few years. You're in Swindon so do you fly there?

You do need more power for a 3 degree approach than a 6 degree one. I always thought the term "glide slope" was a misnomer. 

 

6 degrees ? No such thing I don’t think unless you know one....LCY is 5.5 requiring special certification and special training 

[Pacific231G]

45 minutes ago, rob D2 said:

6 degrees ? No such thing I don’t think unless you know one....LCY is 5.5 requiring special certification and special training 

My normal approaches are a lot steeper than 3 degrees though I don't calculate them  as I'm obviously flying visually. I must measure them on the map and see. 

 

However, the point I was  making that we've rather wandered off from is that a standard 3 degree approach in an airliner or anything else does require more than a trickle of power especially when flaps and gear are out. and that does relate to the noise profile which is below 2000ft over a number of miles and at Heathrow 27 that's almost all over a denselly populated area.   

I don't think that was the case at Filton.

Edited August 19, 2020 by Pacific231G

[RJS1977]

4 hours ago, Pacific231G said:

   If you look at the approach to Heathrow from the other side of the aerodrome in more normal times than now you'll see a line of aircraft all  on exactly the same line and passing over exactly the same streets and houses. 

 

Indeed, I've observed such an alignment from both the old Met Office building in Bracknell, and from Reading Bridge, on numerous occasions.

[rob D2]

You couldn’t be on final at less than 5 miles for ILS as you have to be “ stabilised “ by 1000’ which means gear down , flap for landing , you can be idle power and ideally will be up to that point . Hence they all bore the same hole in the sky .

 

in future GPS RNP approaches will allow much more turns and variety of direction prior to touchdown 

[Pacific231G]

8 minutes ago, rob D2 said:

You couldn’t be on final at less than 5 miles for ILS as you have to be “ stabilised “ by 1000’ which means gear down , flap for landing , you can be idle power and ideally will be up to that point . Hence they all bore the same hole in the sky .

 

in future GPS RNP approaches will allow much more turns and variety of direction prior to touchdown 

Sorry Rob

That doesn't make sense. Do you mean you couldn't turn onto final at less than 5 miles?,*

 

At 5 NM  on Heathrow's ILS approach you would definitely be on final as the standard join is at 2500ft (2423 QFE) 7.5nm out  and would be till the landing phase. What I hear whenever I'm in that part of Richmond (which is about 5NM out) and Heathrow is on 27L is very definitely not engines at idle but by then  .

 

I do wonder about GPS approaches particularly after the New Yorker article I read today.

 

"These days, pocket-sized G.P.S. jammers go for a few hundred dollars each on the Internet and offer an easy out for anyone worried about, say, a surveilling employer. A few years ago, so many truck drivers on the New Jersey Turnpike were using jammers to thwart their bosses’ tracking programs that spillover interference eventually disrupted the G.P.S.-based landing system at Newark Liberty International Airport"

The whole article is here

https://www.newyorker.com/tech/annals-of-technology/how-vulnerable-is-gps?utm_source=pocket-newtab-global-en-GB

 

*(Obviously , I turn onto final at more like a mile or less but that's flying a visual circuit in a light aircraft to a small aerodrome. I aim to complete my turn onto final at about 500ft so if I'm about a mile out then my approach angle is about 6 degrees, even so I need some power on approach, a true glide approach is even steeper)