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Bristol Airport
- Thread starter shropslad
- Start date
stan the man
you are not capable
shropslad said:
sounds like it mark.....i wondered why blu was quiet on here,must be giving them shite over there bl4hbl4h
p0pc0rn41
R
R2B2
Guest
I wonder if they did!
It would be terrific ammo to hit the councils with re the campaign against the use of SMA now that the airport has caved in and are rectifying the problem tonight.
Gerry - any way you could obtain some inside info on whether Bristol used this stuff...??
It would be terrific ammo to hit the councils with re the campaign against the use of SMA now that the airport has caved in and are rectifying the problem tonight.
Gerry - any way you could obtain some inside info on whether Bristol used this stuff...??
Sorry Rob ... nowt to do with SMA I'm afraid.
A short "laymans potted version" is:
Runways achieve a good wet braking surface by one of two methods.
They either use a porus top section which allows any surface water to quickly move away. Or they use a grooved top section - I think this is the most popular method. The grooved section moves the water away via the grooves.
Both methods are to try and keep the section of tarmac in contact with the dunlops as clear of staanding water as possible.
Bristols problem is that with only a single runway they have to do the work in sections each night. I also believe that what they've been doing is not just "top section resurfacing" but "base section renewal"
Doing the base section means the work takes much longer and you may well find yourself having to put down a top layer one night that will be removed again the next night to carry on completing that base section!!!
The grooves are mechanically cut into the new surface, but it has to be allowed to "cure" before that can be done. if you're putting down a top section that will last only one day then I guess you'd proly try and avopid the cost/time taken to groove if you can.
Airports with single runways generally schedule this work for the winter months simply because the number of night movements (= lost revenue) will be less .... of course the weather is also worse so the chances of the work being delayed is higher...... bit of a catch 22.......
I believe that part of the problem had been that normally runway braking condition is generally put out in airport weather forcasts by way of a broad description applicable to three sections of the runway ...... so you get things like wet/wet/wet, good/good/good, good/poor/wet etc.
But where you have actual changes in the surface material that description may not really give a good feel to what it'll feel like when landing.
Bristols situation has been that the centre section has recently been the problem area. This means that the area of the runaway on which you proly need to do max braking regardless of landing direction is the area where it's most "iffy".
There have recently been a few aircraft reporting concerns of getting close to "brown trousers" which havn't made the general news.
In a few cases these a/c felt the dodgy braking so eased off, by the time they could use the brakes in anger while they did stop they were so close to the runway end that they either damaged some of the runway lights or didn't fancy doing a 180 turn and maybe sticking a wheel on the grass - so they had to send out a tug to turn and drag 'em in.
The problem has been at it's worst during crosswind landings, with the higher winds recently this made it more of an issue. High crosswinds mean you really want all the braking you can get to transition from flying to taxying as quick as possible.
Eventually the airlines started to apply much lower than normal corsswind limits to a/c into Bristol using their own assesment of the centre runway section effectiveness rather than the sections either side.
Result was then that any crosswind when the runway was wet meant they could't fly in.
It's interesting to me to see airlines operating similar a/c arriving at very different conclusions...... one low cost operator quickly decided to go elswhere despite the cost of this to them .... annother low cost operator with the same a/c type kept operating as normal!!!!! Hmmmmmmm........
Annother operator (turbo probs this time) continued to operate inot Bristol even though it was one of theirs had the most serious (I'm led to believe) "on the grass excursion".
Personally I think they've been a tad unlucky together with some piss poor decisions ........ if they'd listen more to some wise folks rather than counting the beans they might have made good decisions earlier. As it is they give the impression that they still don't think there's anything really wrong but they'll grudginly do something!!!
This is a bit a "potted explanation" which I hope gives some insight..... here are bits that can be clarified in more detail but this gives the gist I think.....:yo:
A short "laymans potted version" is:
Runways achieve a good wet braking surface by one of two methods.
They either use a porus top section which allows any surface water to quickly move away. Or they use a grooved top section - I think this is the most popular method. The grooved section moves the water away via the grooves.
Both methods are to try and keep the section of tarmac in contact with the dunlops as clear of staanding water as possible.
Bristols problem is that with only a single runway they have to do the work in sections each night. I also believe that what they've been doing is not just "top section resurfacing" but "base section renewal"
Doing the base section means the work takes much longer and you may well find yourself having to put down a top layer one night that will be removed again the next night to carry on completing that base section!!!
The grooves are mechanically cut into the new surface, but it has to be allowed to "cure" before that can be done. if you're putting down a top section that will last only one day then I guess you'd proly try and avopid the cost/time taken to groove if you can.
Airports with single runways generally schedule this work for the winter months simply because the number of night movements (= lost revenue) will be less .... of course the weather is also worse so the chances of the work being delayed is higher...... bit of a catch 22.......
I believe that part of the problem had been that normally runway braking condition is generally put out in airport weather forcasts by way of a broad description applicable to three sections of the runway ...... so you get things like wet/wet/wet, good/good/good, good/poor/wet etc.
But where you have actual changes in the surface material that description may not really give a good feel to what it'll feel like when landing.
Bristols situation has been that the centre section has recently been the problem area. This means that the area of the runaway on which you proly need to do max braking regardless of landing direction is the area where it's most "iffy".
There have recently been a few aircraft reporting concerns of getting close to "brown trousers" which havn't made the general news.
In a few cases these a/c felt the dodgy braking so eased off, by the time they could use the brakes in anger while they did stop they were so close to the runway end that they either damaged some of the runway lights or didn't fancy doing a 180 turn and maybe sticking a wheel on the grass - so they had to send out a tug to turn and drag 'em in.
The problem has been at it's worst during crosswind landings, with the higher winds recently this made it more of an issue. High crosswinds mean you really want all the braking you can get to transition from flying to taxying as quick as possible.
Eventually the airlines started to apply much lower than normal corsswind limits to a/c into Bristol using their own assesment of the centre runway section effectiveness rather than the sections either side.
Result was then that any crosswind when the runway was wet meant they could't fly in.
It's interesting to me to see airlines operating similar a/c arriving at very different conclusions...... one low cost operator quickly decided to go elswhere despite the cost of this to them .... annother low cost operator with the same a/c type kept operating as normal!!!!! Hmmmmmmm........
Annother operator (turbo probs this time) continued to operate inot Bristol even though it was one of theirs had the most serious (I'm led to believe) "on the grass excursion".
Personally I think they've been a tad unlucky together with some piss poor decisions ........ if they'd listen more to some wise folks rather than counting the beans they might have made good decisions earlier. As it is they give the impression that they still don't think there's anything really wrong but they'll grudginly do something!!!
This is a bit a "potted explanation" which I hope gives some insight..... here are bits that can be clarified in more detail but this gives the gist I think.....:yo:
R
R2B2
Guest
Thanks Gerry - very interesting insight as to what's really going on there!
If the operator who went elsewhere is right, then hats off to them for putting safety first. At the same time that would make the other operator wrong... therefore putting cost as the priority over safety.... and for that they should burn in hell.
Now that IS worrying!! Problem being - we don't know which one has it right.Duck n Dive said:
If the operator who went elsewhere is right, then hats off to them for putting safety first. At the same time that would make the other operator wrong... therefore putting cost as the priority over safety.... and for that they should burn in hell.