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Nothing wrong with V/S wiley.
Just expressing my aversion to having procedures that are adopted on every occasion. Its a toolbox, and you use the right tool at the right time.
My apologies if my tone was offensive.
Open climb, similar to LVL CHG on the boeing.
I am probably not an airline pilot but then I am being paid as one so that'll do for me!
Just expressing my aversion to having procedures that are adopted on every occasion. Its a toolbox, and you use the right tool at the right time.
My apologies if my tone was offensive.
Open climb, similar to LVL CHG on the boeing.
I am probably not an airline pilot but then I am being paid as one so that'll do for me!
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Well gents, while we're all apologising, let me humbly do so as well.
I understood the term 'open climb' (and more particularly, 'open descent'), to mean climbing/descending in vertical speed with no 'safety net' like a built-in altitude capture mode at the end of the climb/descent, (hence the term open climb/descent, as in 'no end to it', or 'unprotected').
I think I'm showing my age in assuming that younger aviators would have the same understanding of what I thought to be a common term, which dates back to 707 days (and probably earlier).
The first generation passenger jets had pretty basic flight directors and autopilots with lots more traps for young players than today's do, and one of the real traps was the dreaded ‘open descent’, which was quite literally a killer, and which was part and parcel of selecting vertical speed as the descent mode. In VS mode, ALT CAPTURE mode was disabled, even with a lower altitude dialled into the FMA window. And so pilots quickly learned to avoid this trap by avoiding descending in VS mode.
The auto pilot/flight director designers learned from the shortcomings of their first designs and put in the fix of having altitude capture mode engage when VS mode was selected, (so long, of course, as a lower altitude was selected in the FMA window).
However, many 'old hands' had had it heavily drummed into them that VS mode was a serious no-no in descent because it gave you an 'open (ie, unprotected) descent', and even after the newer aircraft with the more sophisticated flight director/auto pilots came into general use, many old hand trainers and checkers still insisted that VS mode should never be used because that was what they'd been taught and had become used to, (and many's the FO or trainee captain who's had to swallow his objections and utter those well known and oft repeated three letters of the aviation alphabet - Oscar India Charlie - (“Oh, I C [see]”) when the ‘old hand’ trainer wouldn’t listen to his explanation that that particular trap had been made safe). It's still posible to get yourself into an open descent with the new kit if you forget to set a lower altitude in the FMA window, so the old salts still have a point.
jetset, apologies for the snide remark, but to belabour my point: I’m of the school that thinks that when you get really busy, you tend to fall back into the habit patterns you use every day. So I’m inclined to do ‘unnecessary’ things and follow ‘unnecessary’ procedures that 99.9% of the time aren’t in fact really necessary. But on the day when all the holes in the proverbial pieces of cheese line up, maybe that ‘unnecessary’ procedure I always do (and do the same way every time), even when I ‘know’ it isn’t necessary, might just provide one last piece of (hopefully solid) cheese in the line and, (to mercilessly mix my metaphors), break the error chain.
I understood the term 'open climb' (and more particularly, 'open descent'), to mean climbing/descending in vertical speed with no 'safety net' like a built-in altitude capture mode at the end of the climb/descent, (hence the term open climb/descent, as in 'no end to it', or 'unprotected').
I think I'm showing my age in assuming that younger aviators would have the same understanding of what I thought to be a common term, which dates back to 707 days (and probably earlier).
The first generation passenger jets had pretty basic flight directors and autopilots with lots more traps for young players than today's do, and one of the real traps was the dreaded ‘open descent’, which was quite literally a killer, and which was part and parcel of selecting vertical speed as the descent mode. In VS mode, ALT CAPTURE mode was disabled, even with a lower altitude dialled into the FMA window. And so pilots quickly learned to avoid this trap by avoiding descending in VS mode.
The auto pilot/flight director designers learned from the shortcomings of their first designs and put in the fix of having altitude capture mode engage when VS mode was selected, (so long, of course, as a lower altitude was selected in the FMA window).
However, many 'old hands' had had it heavily drummed into them that VS mode was a serious no-no in descent because it gave you an 'open (ie, unprotected) descent', and even after the newer aircraft with the more sophisticated flight director/auto pilots came into general use, many old hand trainers and checkers still insisted that VS mode should never be used because that was what they'd been taught and had become used to, (and many's the FO or trainee captain who's had to swallow his objections and utter those well known and oft repeated three letters of the aviation alphabet - Oscar India Charlie - (“Oh, I C [see]”) when the ‘old hand’ trainer wouldn’t listen to his explanation that that particular trap had been made safe). It's still posible to get yourself into an open descent with the new kit if you forget to set a lower altitude in the FMA window, so the old salts still have a point.
jetset, apologies for the snide remark, but to belabour my point: I’m of the school that thinks that when you get really busy, you tend to fall back into the habit patterns you use every day. So I’m inclined to do ‘unnecessary’ things and follow ‘unnecessary’ procedures that 99.9% of the time aren’t in fact really necessary. But on the day when all the holes in the proverbial pieces of cheese line up, maybe that ‘unnecessary’ procedure I always do (and do the same way every time), even when I ‘know’ it isn’t necessary, might just provide one last piece of (hopefully solid) cheese in the line and, (to mercilessly mix my metaphors), break the error chain.
Last edited by Wiley; 27th Dec 2005 at 00:39.
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This ATSIN ACAS INTERFACE WITH AIR TRAFFIC CONTROL describes to UK ATC their responsibilities following a TCAS RA/TA.
May be of interest in this discussion.
WF.
May be of interest in this discussion.
WF.
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Good link warped factor, and although it says that ATC no longer become responsible for standard separation I would not like to be the one that doesn't give any vectors and then have a nasty due to some problem in executing the RA's. If the blips are going to merge and a resolution reported by any pilot says that standard 1000' or 2000' isn't going to be maintained then I WILL issue vectors. I'd like to see any ATCO that can morally argue against that, after all we are providing a SAFE, orderly and then expeditious service.
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if i'm climbing or descending someone 1000ft below/above i'll almost always tell both parties,especially if the rate of change is particularly good. at least that way both crews are aware and so far,touch wood, it has meant no annoying paperwork.
theres tempting fate for you
.....
theres tempting fate for you
.....
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Good link warped factor, and although it says that ATC no longer become responsible for standard separation I would not like to be the one that doesn't give any vectors and then have a nasty due to some problem in executing the RA's. If the blips are going to merge and a resolution reported by any pilot says that standard 1000' or 2000' isn't going to be maintained then I WILL issue vectors. I'd like to see any ATCO that can morally argue against that, after all we are providing a SAFE, orderly and then expeditious service.
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I agree.
Although I've never had a RA occur on frequency, I would just acknowledge and pass traffic.
As said earlier, I'm sure I read somewhere that there was a concern that the large bank angles from asking pilots to take horizontal action could reduce the climb rate below that required by TCAS.
Although I've never had a RA occur on frequency, I would just acknowledge and pass traffic.
As said earlier, I'm sure I read somewhere that there was a concern that the large bank angles from asking pilots to take horizontal action could reduce the climb rate below that required by TCAS.
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Having had quite alot of RA's on frequency I agree that normally you just let the event happen and give traffic information, with updates if needed. However on one occasion I did face a situation which compromised obtained separation and avoiding action was subsequently given which was considered in the following investigation to have been pertinent to aid the safety of the a/c, not only against the RA traffic, but subsequent tracks that would have posed a threat if the courses of all continued.
ex-Tanker
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"Returning to level..."
5milesbaby,
In your previous post you mention reporting "resolution over, returning to level".
If this is supposed to be SOP after an RA then it is not good. Far better to check all round with ATC what is now the best action isn't it?
By following the RA we have followed the operation of last resort and hopefully averted an accident. By climbing or descending BACK to level without clearance or guidance we would be taking a big chance and possibly creating a second conflicting situation.
FC.
In your previous post you mention reporting "resolution over, returning to level".
If this is supposed to be SOP after an RA then it is not good. Far better to check all round with ATC what is now the best action isn't it?
By following the RA we have followed the operation of last resort and hopefully averted an accident. By climbing or descending BACK to level without clearance or guidance we would be taking a big chance and possibly creating a second conflicting situation.
FC.
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BFU Safety Recommendation No 16/2004
A quote from the BFU accident report -
"Utilizing its own mechanism and international resources available ICAO should ensure that all ACAS/TCAS users are consistent in their response to the equipment advice. ICAO auditing processes must pursue compliance with its ACAS SARPs and training objectives at all levels within the aviation industry."
Mike J's info above shows many of the good words have been written (and there are many more), and others have brought facts that reflect the intended use of TCAS within the aviation system. But the evidence shows that the level of understanding is lacking.
TCAS is good... but only if everyone knows what they are supposed to do. We don't. And someone should be driving this point harder.
The BFU considered it a 'systemic cause' that "the integration of ACAS/TCAS II into the [aviation system] was insufficient and did not correspond in all points with the system philosophy". If the Ueberlingen tragedy is repeated 'systemic cause' could be replaced with 'guilty parties'.
"Utilizing its own mechanism and international resources available ICAO should ensure that all ACAS/TCAS users are consistent in their response to the equipment advice. ICAO auditing processes must pursue compliance with its ACAS SARPs and training objectives at all levels within the aviation industry."
Mike J's info above shows many of the good words have been written (and there are many more), and others have brought facts that reflect the intended use of TCAS within the aviation system. But the evidence shows that the level of understanding is lacking.
TCAS is good... but only if everyone knows what they are supposed to do. We don't. And someone should be driving this point harder.
The BFU considered it a 'systemic cause' that "the integration of ACAS/TCAS II into the [aviation system] was insufficient and did not correspond in all points with the system philosophy". If the Ueberlingen tragedy is repeated 'systemic cause' could be replaced with 'guilty parties'.
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5milesbaby
Fair enough then, if you have plenty of practical experience I shall try to learn from it!
Thinking about it now, do you mean that horizontal AA was used to prevent further losses of separation with other A/C?
Thinking about it now, do you mean that horizontal AA was used to prevent further losses of separation with other A/C?
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Few Cloudy: from CAP 493 (Manual of Air Traffic Services Part 1) which is downloadable off the link
CAP 493 Supplementary Instruction No. 3 of 2005 Para. 3
cdb, what I'm saying is that I would be concerned of letting the blips merge with 2 a/c following RA's that compromises separation and yes, avoiding action was given to overt further losses with other a/c.
Effect on ATC Operations
The effect of advisories on air traffic control operations is as follows:
Traffic Advisory – Pilots are advised not to take avoiding action on the basis of TA
information alone but may ask for traffic information.
Resolution Advisory – Pilots are expected to respond immediately but have been
instructed to restrict manoeuvres to the minimum necessary to resolve the
confliction, advise the air traffic control unit as soon as is practical thereafter and
return to their original flight path as soon as it is safe to do so.
The effect of advisories on air traffic control operations is as follows:
Traffic Advisory – Pilots are advised not to take avoiding action on the basis of TA
information alone but may ask for traffic information.
Resolution Advisory – Pilots are expected to respond immediately but have been
instructed to restrict manoeuvres to the minimum necessary to resolve the
confliction, advise the air traffic control unit as soon as is practical thereafter and
return to their original flight path as soon as it is safe to do so.
cdb, what I'm saying is that I would be concerned of letting the blips merge with 2 a/c following RA's that compromises separation and yes, avoiding action was given to overt further losses with other a/c.
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Thanks for that quote 5milesBaby.
That looks a lot better than calling out "resolution over, returning to level", as it contains the important requirement "safe to do so", which the pilot alone cannot discern.
Thus it requires ATC advice / control to return to level.
FC.
That looks a lot better than calling out "resolution over, returning to level", as it contains the important requirement "safe to do so", which the pilot alone cannot discern.
Thus it requires ATC advice / control to return to level.
FC.
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Number of times the controllers issue a traffic advisory: "climbing traffic is leveling off 1000 ft below you" Then we simply have to watch the aproaching dot on our Tcas screen and confirm that the traffic is actually levelling off 1000 ft below, it works like a charm.
I dont know weather this is statndad ATC procedures, or simply up to the controller if the do this or not.
I dont know weather this is statndad ATC procedures, or simply up to the controller if the do this or not.
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Number of times the controllers issue a traffic advisory: "climbing traffic is leveling off 1000 ft below you" Then we simply have to watch the aproaching dot on our Tcas screen and confirm that the traffic is actually levelling off 1000 ft below, it works like a charm.
It makes me aware that an aircraft is approaching "my" level with high vertical speed so I can check that it is really leveling off. The climbing or descending aircraft is made aware as well and can adjust vertical speed to prevent a RA.
Changing software or modifying AP to match TCAS thresholds is a little bit overdone to my opinion. I am lucky to fly a modern aircraft and have never seen the AP significantly overshooting an assigned altitude. Although in some cases it might cause a RA for other aircraft. But when these situations arise VS can be reduced by pilot intervention.
We can ask the authorities to make more rules and regulations to try to cover any possible situation we run into. Or ask the technicians to better program our AP software. But to my opinion it should be up to the guys in front and the guys on the ground behind the screens to manage these situations. That's why we get the big $$$ isn't it?
Plumbum Pendular
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we simply have to watch the aproaching dot on our Tcas screenwe simply have to watch the aproaching dot on our Tcas screen