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jour-no-list
4th Jul 2002, 18:45
AIRPROX

Could anyone help me on this ASAP. How significant is this - do these happen all the time? I understand they came within a 1000 feet of each other (is this close)

email me at [email protected]

PRESS RELEASE FROM THE CIVIL AVIATION AUTHORITY WEBSITE

An Aircraft Proximity (Airprox) report has been filed with the Civil Aviation Authority involving an Embraer 145 and a De Havilland Canada Dash 8. The incident took place 10 miles east of Llandrindod Wells, Powys on Wednesday 3 July at 1915 hours.

The Embraer 145 was in-bound to Bristol and the Dash 8 was en-route to Newcastle. Both aircraft were receiving an air traffic control service from the London Area Control Centre. The incident took place at approximately 18,000 feet.

These details are subject to assessment by the independent UK Airprox Board. During January to June 2001 there were 44 airprox incidents involving civil air transport and 33 of these were assessed as having no risk of collision.

Carnage Matey!
4th Jul 2002, 19:01
1000 feet is a fairly long way apart (in fact its the normal vertical seperation, but as this is classed as an airprox then I guess you mean they were laterally seperated). The severity of the incident is dependent on a number of factors including relative tracks of the aircraft, closing speeds, whether the aircraft were visual with each other or not, etc etc. As none of these details are in your initial post its rather difficult to comment. Airproxes are rare in the UK and flying is still the safest way to travel by far. That said I have no doubt the media (and that includes the beeb) will be reporting the 'near death' experience of these passengers tomorrow regardless of what we say here. After all "HUNDREDS CHEAT DEATH IN JUMBO NEAR MISS - PILOTS IN PANIC DEATH DIVE - more bad news for troubled ATC centre - is it a gypsy curse?" is a lot more news worthy than "Rare loss of ATC seperation reported over Wales. Both aircraft continued safely to destination"

Ex Servant
4th Jul 2002, 21:24
We're about to find out how it's reported. The beebs news website has a latest saying 'inquiry into how two BA aircraft came close to collision' No further posted just yet.
I for one have in the past spoken to the press and regreted it afterwards. Rather than everyone saying nothing and the press printing sensationist headlines is there a case for those currently working in the industry (ie not those of us who used to, recent views noted) having some organised links to the press to advise them on what the truth actually is when these sort of things occur/appear to occur? Might it make for more accurate reporting and less concern for the fare paying public?

Long Sleep
4th Jul 2002, 21:42
It was one of the closest !!

ERJ145 descending to cleared level 1000ft above Dash-8 in level flight opposite direction. TCAS RA "Descend" for the 145.
Traffic info given, pilot follows the RA and dives through the Dash-8`s level, head on and very close.

Very worrying in view of this weeks tragic event!!!

Carruthers
4th Jul 2002, 21:52
I would have thought that Journ-o-list and others monitoring these forums will lap up such 'sensational' stuff as the above without necessarily understanding what is happening. Don't talk to the press / media folks, leave that to the clowns of Flight and Channel 4.

fireflybob
4th Jul 2002, 21:57
Whenever we are faced with challenges then it's best to tell the truth.

The facts are that flying is risky!!

If you are going to pack scores of fragile people in narrow tubes and shoot them through the air at 600 mph supported on wings full of inflammable explosive then you shouldn't perhaps be surprised if, occasionally, things go wrong!! Throw in the odd proximity of other flying machines then you increase the risk factor.

This is not a reason for complacency since those of us who are intimately involved in the industry are constantly striving for perfection.

The problem with the media is that they have to appeal to the ranks of the "great-unwashed" and dumb down the facts to keep them hungry. Bad news sells the newspapers!

What about circa 3,500 pople killed on UK roads every year (that's about 10 a day!!!) - if ever there was a national tragedy to report this must be it. Compare this to the hysterical media reaction to the Hatfield train accident (by this I am not belittling the loss of life in this or any accident).

Personally I have decided not to read a newspaper or listen to he news - we have a choice, use the off switch and cancel the papers!

I am not saying we shouldn't be concerned with what's going on in the world but it's also important to keep it in perspective.

Big Nose1
4th Jul 2002, 22:12
Look in ATC Issues "Nasty Incident" Guys.

Carnage Matey!
4th Jul 2002, 22:55
Flying is not risky, but it is very dangerous. The actual risk of anything happening is extremely remote.

High danger x extremely low risk = safe travel.

The thread on the ATC forum contains an excellent explanation of the workings of TCAS when issuing RAs which cross levels. The system worked as designed - panic over.

Long sleep - by 'one of the closest' do you include the well documented F15/767 airprox over DTY last year which was very close, or the more recent Air UK/F15 inbound to MME, which was estimated to be around 500 ft seperation? Perhaps it would have been more accurate to say:

"Traffic info given, Embraer pilot follows the RA, Dash 8 pilot follows the RA, Embraer descends through DH8s level to achieve optimum seperation as determined by TCAS."

TCAS doesn't really command 'dives' as such, just descent rates which would not be out of place in normal operations!

Big Nose1
4th Jul 2002, 23:16
Carnage,

Yes the thread contains an excellent explanation, however i disagree that the system worked as designed. TCAS is there to back up ATC when we get it wrong as we do sometimes, in this situation ATC got it entirely correct..ie Embraer descended 1000 on top of DH8-panic over.

For the Embraer to then descend through the DH8 level in response to TCAS RA as discussed is a TCAS induced loss of separation. Imagine the poor ATCO, 2 days after the DHL collision he watches an a/c descend through another 2 miles head on working on 100 mile range, labels garbled, blips merge, Embraer appears out the other side 300ft below DH8. If he is not off work with stress for some days i will be surprised.

We need to continue to develop TCAS and use all incidents to make aviation safer for all.

Woodman
5th Jul 2002, 06:46
Following the thoughts above that we should have a 'spokesperson' to explain aviation matters to the media, the question is who?
Almost everyone has an axe to grind and such 'bias' would be immediately shouted down by others and the matter would descend to farce, probably to the joy of sections of the media. See almost any thread in PPrune:)
I would nominate the Civil Aviation Authority to take the role but I wouldn't want to be the one to do it.

Seriph
5th Jul 2002, 07:02
We already have 'expert' commentators, certain idiots from Flight and ex navs from the back of Tornado's. They unforunately seem to be either incompetent or playing the media game.

MarkD
5th Jul 2002, 09:13
Maybe PPRuNe should have an "Editorial" forum where Danny can tell the journos how it is - god knows they quote him so often these days he should be demanding some shekels from them to keep the servers running :D

Konkordski
5th Jul 2002, 10:50
The irony is amazing. One minute you're condemning journalists for making exaggerated statements and not reporting the truth, the next you're committing the very same crime yourselves by denouncing all journalists as idiots, clowns, etc.

Want respect? Respect others. It's been said countless times on this forum and still some of you don't learn. You'll reap what you sow.

Air Vent, well said. Trustworthy links with respected media (and there are some) are the way forward.

activewaypoint
5th Jul 2002, 11:13
It does seem rather unlikely that having descended to a level 1000above the dash 8, that TCAS would command a further descent..........it doesn't work that way.

Suggs
5th Jul 2002, 11:26
The amount of traffic in the air especially in some parts of the world is very high. This was not the case that night in Switzerland.

The TCAS symbols often change on a normal flight from clear white to solid white. Indicating that the other A/C is fairly close within 1000' or so. Occationally they change from Solid White to Solid Yellow. This is highlighted by an oral TRAFFIC.

This is a great big wake up call and will wake the dead.

If it then goes red then you are instructed to climb or descend, it's called a resolution advisory. I've had 1 RA go off not on my A/C but on frquency. Both pilots were trying to negoicate with ATC a resuce plan before each A/C was told to climb or descend. In busy airspace the controller c.ocked up apologised and informed everyone that he was going to file a report.

Everyone at all stages new what was happening and acted professionally, didn't panic, didn't need to panic.

Accidents don't happen becasue of one thing. They are a chain of events. 5 men got it wrong, 2 russian, the DHL lads and the controller.

We can see everone on TCAS(Radar) and the bottom line is that it's the Captains ultimate responsability to ensure the safe operation and seperation of that A/C. In clear conditions at night or during the day, that means looking out of the window and visually identifying to teh best of his abilities the other A/C.

We are trained to follow proceedures but at the end of the day if a pilot thinks that following procedure will endanger the A/C he should and will do exactly what he thinks is nessessary. That is why pilots flyy A/c and not computers.

I don't trust journalists, whatever conlcusions they draw and publish lets hope they try to match the same professional standard that every airline pilot that I have ever met works to.

under_exposed
5th Jul 2002, 11:34
activewaypoint, BBC site says the dash decended and the EMB climbed

Konkordski
5th Jul 2002, 11:47
Those disgraceful journalists have been saying terrible things about those two outstanding professional America West pilots recently.

I look forward to the inevitable clearing of the names of these professional members of the pilot community and their immediate reinstatement as flight crew.

After all, if they were intoxicated (as it's alleged, dear me, can't possibly be true) it stands to reason that every pilot in the world is fundamentally untrustworthy. Or does that kind of reasoning only applies to journalists...?

A-V-8R
5th Jul 2002, 12:34
Being the slug I am I left my manuals in Operations at the airport; however, I do recall reading in the TCAS section a warning about;

Reducing the rate of Climb or Descent the last 1500 feet upon leveloff to preclude nuisance RA's with other Climbing/Descending traffic.

I can't recall the exact FPM climb our manuals say (And your manuals might have something different; there are different versions of the software out there) but I do know that it can make the difference in having an RA or not.

By the way, also in our manual, it says while the displayed range of targets can be up to 40 miles; only 7 miles range is garanteed.

Scimitar
5th Jul 2002, 14:47
This sounds very like what is known as a "TCAS crossover", of which there have apparently been a few occurences in the States.

It happens when one aircraft is descending towards another which is climbing. Basically the TCAS equipment of each aircraft "sees" the other as head-on and then makes its decision on which way to organise the separation. If it decides that the descending aircraft should pass beneath the climbing aircraft, and both crews follow the TCAS, then both will go through their cleared level, crossover, and then return to their assigned levels. This is much easier to describe with a diagram!

The moral, of course, is to reduce the rate of climb or descent to less than 1000ft/min when within the last 1000ft. And for you controllers out there, it will always help to remind pilots of this if you advise us that there is opposite traffic climbing/descending to 1000ft of our cleared level.

The really frightening time comes when one of the crews decides to ignore the TCAS (probably because they have visual contact). As happened over Japan not too long ago a 747 and DC10 missed by something in the order of 20ft.

Deadleg
5th Jul 2002, 16:25
Listen, I'm on the Dash 8 fleet for BACX(no it was'nt me nor do I know who was involved)but can I plead for all of you, including journalists to wait for the CAA to investigate and publish its findings.

In the meantime I'm simply relieved beyond words that there was'nt a mid-air!!!

trolleydollylover
5th Jul 2002, 20:26
In the Army we had a hard and fast rule...Say **** all...and let the person who is paid and trained for to speak to the jornos. That way any little phrase that you say even in jest, cannot be interpreted as a shock horror story for the gutter.

They will do it, it is our jobs that we are speaking about, some of you should be ashamed of yourselves... probably spotters...if the cap fits, wear it. Shut Up.

I listerned to radio one today, and I can only say that the radio news service is complete and utter garbage...garbage and yet more dumb garbage.

The language and content of the news stories is insulting to the listener much is fabricated. It is amazing how the real news is missed for sentsationalism.

I am sure that you have observed how many have read this forum and not commented.

"Please help ASAP..." says it all really...

Seriph
5th Jul 2002, 20:54
So Suggs you don't like jurnos, doesn't stop you airing complete crap on these pages though does it. So five guys got it wrong did they, what the hell do you know about it.

Cough
6th Jul 2002, 00:09
Just taking a pause from the main thread for a while, and just delving into the journo-bashing bit.

I would just like to take 2 minutes of the collective audience from the media to suggest something. And that is, once an article is written why don't you send it to the Ops department for the airline/airport concerned for them to comment on its factual content. If they don't want it published then that’s one thing, but they may be able to point out that the 'Jumbo' was in fact something completely different. Post Sep11 we need passengers to have a positive attitude to flying, by taking out the little mistakes contained in the articles may enhance that a little. You may even get some more respect from the readers of this forum!

Your thoughts please...Cough:)

5milesbaby
7th Jul 2002, 06:54
It does seem rather unlikely that having descended to a level 1000above the dash 8, that TCAS would command a further descent..........it doesn't work that way.

Seems that this is what actually happenned. We'll wait for the final investigation to take place but the results I fear will not be in favour of TCAS. This has happenned before on a much less severe scale, and is triggered by high rate of descent/climb, TCAS assesses the closure rate and decides to act accordingly. Its why ATC, when able, will give traffic info to IFR in Classes A/B. Our conflict alert will be activated, so we ensure both aircraft are aware of each other and re-inforce the cleared levels. I say 'when able' as its not a requirement, and there are times when far more important things need to be done.

zonoma
7th Jul 2002, 07:04
Are pilots losing faith in TCAS or even ATC as a result of all these incidents?? I ask as the usual night time short cuts we ATCers are happy to comply with, seem to be getting turned down recently as soon as the 'outside CAS it'll be a RAS' is added. Its very unusual for this to happen as in my experiences a/c are not descended below FL100, and its officially night time, so if anything is out there it has to display Mode A AND C and will normally be in contact with an ATC unit somewhere. Even if its not our unit we can decifer from the Squalk which it is and then communicate accordingly. Have airlines imposed any restrictions concerning this because it baffled me when one after another turned down the short cut :confused: :confused: :confused:

Hand Solo
7th Jul 2002, 15:20
Well I'll still be following the TCAS. We have yet to see anything concrete on the TCAS status of the Tu154, or whether or not it issued an RA, or whether or not it was followed were it issued. That, to me, means there is no evidence of a TCAS failure in this situation. A smoking hole in the ground there may be, but until such time as there is proof positive of a TCAS failure I'll go with the untold number of potential collisions averted rather than the one incident in which it may have been a causal factor. What I think we will see is an increased awareness of the risks of high climb/descent rates when proximate with other traffic and a reduction in the number of RAs as a result. Perhaps its time to specify maximum as well as minimum rates of climb and descent in congested airspace?

nightman
17th Jul 2002, 21:10
Hope I'm not too late to get involved in this or add my tuppence worth, but I think the idea of having some
members who are willing to talk the press is a great idea. And yes I work for a newspaper. Personally speaking,
I think the idea of having experts in their fields to talk to is incredibly useful and would welcome links
between journos and professionals on here.

In an ideal world a paper's transport correspondent would have contacts who could answer all their questions,
and would be available on the end of a phone as and when they needed to talk to them. Unfortunately that doesn't
always happen. Transport corrs usually cover a huge area - trains, planes, boats, cars, unions involved with
these areas, professional bodies, regulatory bodies, the government to name but a few. It's a lot of work and
it will not always be easy to get answers from official press officers who may be trained to withhold information
(when there's a disaster of some sort) rather than release it as and when they get it.

Now, I've only recently found this website, but I've found it very useful. Mostly in terms of understanding terms
and things because I haven't really had much contact with anyone else on it. In trying to answer cough's
question: in my own experience I haven't had the luxury of time to send copy to airlines to get them to go
through it for mistakes. I've been working nights and the two recent crashes I've covered (simply because I'm
working - I'm not the transport corr and have no background in transport) have been a matter of hours before our final deadlines. They've also happened in the evenings and that's also not a good time to get most people at work.
When you do get someone they seem more concerned at limiting liability than telling you what happened.

Professionally speaking I, like most journalists I would think, don't like to get things wrong but it does happen
given the time constraints we work under. The paper I work for has a policy of trying to correct any mistakes
as soon as possible if we're notified of them. I believe the paper is happy to do this, because we know we don't
always get it right. We also think it means people will trust us more if we're seen to be willing to correct our
errors. A case of we got it wrong, we'll hold our hands up and say, sorry we'll try not to do it again.

As for why we try to find out what has happened I think it is because people want to know. If there's been a
crash or a near miss, that is news and people want to know about it. I'm not advocating that we speculate as
to why these things happen, but if by talking to professionals who can give educated opinions on something
then we'll try to use that in context. Waiting for an official investigation and report (while still reporting it
when it comes out) does not tell people the news, and if a plane has crashed then people need to be told. I agree
that we shouldn't (and would like to think we don't) jump to any conclusions about a crash, but if there's
relevant information then we should include it.

This post is a bit longer than I intended so I'll stop now, but what I will say is that if anyone has any questions
they think I can answer I'll gladly do my best to reply. Most of us see our jobs as letting people know what has
happened, and reporting accurately on the events. I know sometimes that doesn't always happen and that
sometimes papers will run stories that are sensationalist - if you read those sorts of papers then you can
probably expect it. My advice would be don't read them. But do remember, we're less likely to make mistakes
if we have people who know what they're talking about who can tell us, and help us get it right.