BOI into the 2012 Tornado Collision over the Moray Firth
MB:-
Very well, because Air Safety spending was ring fenced, SVOs did not seek to subvert it by ordering the suborning of the Regulations, experienced and trained engineers knew the Regs and implemented them to the letter, instead of being sacked and replaced by those who didn't and weren't, and the Regulations were gradually modified and updated instead of being trashed and replaced from an MAA Year Zero.
In other words we had been spared an H-C 'Golden Period' back then!
How the hell did we cope 40 years ago when the RAF had more squadrons than it now has FJs?
In other words we had been spared an H-C 'Golden Period' back then!
Deliverance, nobody is saying that 40 years ago everything was perfect, it never was and it never will be. All we are saying is that a sustained attack on Military Air Safety was later made from which it still hasn't recovered. Why that is is the crux of the matter. It is my belief, and that of others, that it is because those who carried out that attack, and those who then covered it up, are still being protected.
If that is accepted then the only solution is to move Air Safety governance away from those who are thus subverting it, which means outwith the MOD. Ditto all the above wrt the MilAAIB. Once those two bodies are made independent of the MOD, and of each other, then the real business of Air Safety can begin.
If then the MAA requires all FJs to carry TCAS then they must, and yes the tax payer will pay for it. If they don't then they won't. The MAA will be the Regulatory Authority, not the MOD, not the SoS, not the RAF, not the CAS, certainly not me, but the MAA.
As to Accident Investigation, ditto wrt the MilAAIB.
As to GA, ditto wrt the CAA.
If that is accepted then the only solution is to move Air Safety governance away from those who are thus subverting it, which means outwith the MOD. Ditto all the above wrt the MilAAIB. Once those two bodies are made independent of the MOD, and of each other, then the real business of Air Safety can begin.
If then the MAA requires all FJs to carry TCAS then they must, and yes the tax payer will pay for it. If they don't then they won't. The MAA will be the Regulatory Authority, not the MOD, not the SoS, not the RAF, not the CAS, certainly not me, but the MAA.
As to Accident Investigation, ditto wrt the MilAAIB.
As to GA, ditto wrt the CAA.
Last edited by Chugalug2; 12th Jul 2014 at 06:52. Reason: Words, dear boy, words!
Deliverance
You make perfectly fair points which deserve discussion.
I think we must accept that very few accidents have a single cause. The “Reason Model”, which MoD teaches, characterises it as many slices of cheese, with many holes, whose size is constantly changing. The “accident trajectory” occurs when they momentarily line up.
Problems ARE always present (i.e. as you say, nothing is ever perfect) but the number of slices and fewer/smaller holes are defences in depth. Correct implementation of mandated regulations is one of the biggest and most important defences. In doing so, you avoid the avoidable, leaving time and resources to manage the unavoidable. In Tornado, CWS is one defence, which as you and others say we have done without until now.
But the problem Chug speaks of is that MoD has quite deliberately stripped away the defences. MoD staffs are now spending time and money on retrospectively managing the avoidable. Not just avoidable; but quite deliberate decisions taken to render aircraft unsafe, despite many warnings. For example, the un-ring fencing of airworthiness funding in 1991 and 3 successive years of 28% cuts. I accept that, to today’s staffs, they are faced with this frustration. But I also believe there to be very few in MoD who can articulate cause and effect, which makes it very difficult to make a case for resource.
The ASaC mid-air was a perfect example and the BoI, uniquely in my experience, talked about the defences being stripped so much that crews were only left with one; their own eyesight, at 0400, in pitch darkness, after a recent sand storm. Systems which many pilots had barely thought of (because, unwittingly, they had other defences) became critical. In that case, the BoI did very well given they were serially lied to and deceived, with crucial files “missing”. This Tornado mid-air isn’t too different in most respects.
But sometimes the defences you build just cannot prevent recurrence. Especially when the legal obligation to try to avoid recurrence is deliberately ignored and the oversight process suborned. (Chinook ZD576 is a good example). In this case, as Distant Voice said, there were far too many Tornado mid-airs and near misses and OR(RAF) correctly ran a requirement for a CWS. Sometimes you must temporarily accept the risk (and try to bolster other defences) because the technology simply isn’t available or, commonly, is too heavy and bulky for a small aeroplane like Tornado. For example, wire-strike warning technology has always been needed, but it wasn’t until 1986 it was miniaturised to an acceptable degree. Not sure when that Tornado requirement is going to be resurrected, or if it has been embodied in Typhoon and F35. (The designer sits patiently awaiting MoD – I’m off to see him shortly and perhaps waste a good walk!) It may be that the RAF decided not to proceed in 1986 because other defences were deemed sufficient, but I mention it because it has resonance with this CWS case.
One crucial piece of evidence Haddon-Cave used (but presented as his own) was the relative inexperience of the MoD staffs who manage all this. The last major aircraft programme I managed saw the prime contractor appoint the company’s most senior programme manager as Risk Manager. In purely grade terms he was more senior to the programme manager. By 1996 he knew all about MoD’s run down of its airworthiness system and exploited it mercilessly. (H-C studiously avoided this bit). By contrast, my 2 Star flatly refused to approve me having a Risk Manager at all. I did it myself, but senior management issued orders that no-one was to engage in Risk Management, or submit Risk Notifications. In 7 years, only one notification was submitted. Yet the biggest risk was inability to achieve airworthiness certification, RTS or enter Service, because the same management had directed that, for example, the Mission Trainer (among other airworthiness pre-requisites) should not be procured. Ever. The same management who ignored the recommendation to conduct fleet checks on Tornado IFF functional safety. Mitigation was to completely ignore our 2 Star, and treat him as if he didn’t exist. Which was actually pretty easy, as he made no effort to do his job anyway. Too busy making sure his ethos was embedded in his pet projects, Nimrod MRA4 and Chinook Mk3. Successfully, to be fair, as the predicted came to pass.
Therein lies the root of our problems. It only takes one or two to undermine the whole shebang. I often wonder what steps the MAA would take if that happened today. That 2 Star, and his bosses, may be retired, but he has been replaced by those he taught. Do they have their SQEP status withdrawn for example? If a procurement 1 or 2 Star isn’t a SQEP in his field, surely they must go? I hear whispers the MAA is quite robust in this area, which if true is good news. They’re learning to implement mandated regulations, and avoid the avoidable!
You make perfectly fair points which deserve discussion.
I think we must accept that very few accidents have a single cause. The “Reason Model”, which MoD teaches, characterises it as many slices of cheese, with many holes, whose size is constantly changing. The “accident trajectory” occurs when they momentarily line up.
Problems ARE always present (i.e. as you say, nothing is ever perfect) but the number of slices and fewer/smaller holes are defences in depth. Correct implementation of mandated regulations is one of the biggest and most important defences. In doing so, you avoid the avoidable, leaving time and resources to manage the unavoidable. In Tornado, CWS is one defence, which as you and others say we have done without until now.
But the problem Chug speaks of is that MoD has quite deliberately stripped away the defences. MoD staffs are now spending time and money on retrospectively managing the avoidable. Not just avoidable; but quite deliberate decisions taken to render aircraft unsafe, despite many warnings. For example, the un-ring fencing of airworthiness funding in 1991 and 3 successive years of 28% cuts. I accept that, to today’s staffs, they are faced with this frustration. But I also believe there to be very few in MoD who can articulate cause and effect, which makes it very difficult to make a case for resource.
The ASaC mid-air was a perfect example and the BoI, uniquely in my experience, talked about the defences being stripped so much that crews were only left with one; their own eyesight, at 0400, in pitch darkness, after a recent sand storm. Systems which many pilots had barely thought of (because, unwittingly, they had other defences) became critical. In that case, the BoI did very well given they were serially lied to and deceived, with crucial files “missing”. This Tornado mid-air isn’t too different in most respects.
But sometimes the defences you build just cannot prevent recurrence. Especially when the legal obligation to try to avoid recurrence is deliberately ignored and the oversight process suborned. (Chinook ZD576 is a good example). In this case, as Distant Voice said, there were far too many Tornado mid-airs and near misses and OR(RAF) correctly ran a requirement for a CWS. Sometimes you must temporarily accept the risk (and try to bolster other defences) because the technology simply isn’t available or, commonly, is too heavy and bulky for a small aeroplane like Tornado. For example, wire-strike warning technology has always been needed, but it wasn’t until 1986 it was miniaturised to an acceptable degree. Not sure when that Tornado requirement is going to be resurrected, or if it has been embodied in Typhoon and F35. (The designer sits patiently awaiting MoD – I’m off to see him shortly and perhaps waste a good walk!) It may be that the RAF decided not to proceed in 1986 because other defences were deemed sufficient, but I mention it because it has resonance with this CWS case.
One crucial piece of evidence Haddon-Cave used (but presented as his own) was the relative inexperience of the MoD staffs who manage all this. The last major aircraft programme I managed saw the prime contractor appoint the company’s most senior programme manager as Risk Manager. In purely grade terms he was more senior to the programme manager. By 1996 he knew all about MoD’s run down of its airworthiness system and exploited it mercilessly. (H-C studiously avoided this bit). By contrast, my 2 Star flatly refused to approve me having a Risk Manager at all. I did it myself, but senior management issued orders that no-one was to engage in Risk Management, or submit Risk Notifications. In 7 years, only one notification was submitted. Yet the biggest risk was inability to achieve airworthiness certification, RTS or enter Service, because the same management had directed that, for example, the Mission Trainer (among other airworthiness pre-requisites) should not be procured. Ever. The same management who ignored the recommendation to conduct fleet checks on Tornado IFF functional safety. Mitigation was to completely ignore our 2 Star, and treat him as if he didn’t exist. Which was actually pretty easy, as he made no effort to do his job anyway. Too busy making sure his ethos was embedded in his pet projects, Nimrod MRA4 and Chinook Mk3. Successfully, to be fair, as the predicted came to pass.
Therein lies the root of our problems. It only takes one or two to undermine the whole shebang. I often wonder what steps the MAA would take if that happened today. That 2 Star, and his bosses, may be retired, but he has been replaced by those he taught. Do they have their SQEP status withdrawn for example? If a procurement 1 or 2 Star isn’t a SQEP in his field, surely they must go? I hear whispers the MAA is quite robust in this area, which if true is good news. They’re learning to implement mandated regulations, and avoid the avoidable!
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What is ALARP?
In 1991 a specification was drawn up for Fast Jets for a piece of airborne equipment "to enable a very significant reduction in the risk of mid-air collisions"; in effect make the collision risk ALARP. The specification called for;
(1) Combined closing speed of 1000 kts
(2) Host bank angle of 60 degrees with 15 degree roll rate/sec
(3) 2g turns by host aircraft
(4) Maximum search range of 18 nm
(5) +/- 60 degree of azimuth from host's boresight and +20 degrees and -10 degrees of elevation
(6) Operates within the altitude range 200 - 5000 ft
(7) Provide alerts within 15 secs to interception (Tau). (a) Threat level 1, where Tau is between 5 and 15 secs. (b) Threat level 2, where Tau is between 0 and 5 secs, of pop-up target at 2 nm or less.
(8) Discriminate between threats separated by at least 1 nm in slant range.
The flight trial results and the 1998 OR(Air) document make it clear that the specification was met. Unfortunately, the programme was halted and with it the progress towards ALARP. Despite all the "smoke and mirrors" between 1998 and the time of the Moray Firth collision, the specification requirement was not fulfilled and the risk of collision remained NOT ALARP.
Currently, we are in the process of evaluating a piece of off the shelf equipment which falls short of the 1991 (ALARP) specification, and as a consequence the collision risk remains NOT ALARP. Probably that is the reason why the Risk Register shows no projected change in the Risk Index after TCAS has been fitted. It now seems a case of fitting any collision warning system simply to address the "societal concern".
N.B. This shold be read in conjunction with posting #250 "What is Tolerable"
DV
(1) Combined closing speed of 1000 kts
(2) Host bank angle of 60 degrees with 15 degree roll rate/sec
(3) 2g turns by host aircraft
(4) Maximum search range of 18 nm
(5) +/- 60 degree of azimuth from host's boresight and +20 degrees and -10 degrees of elevation
(6) Operates within the altitude range 200 - 5000 ft
(7) Provide alerts within 15 secs to interception (Tau). (a) Threat level 1, where Tau is between 5 and 15 secs. (b) Threat level 2, where Tau is between 0 and 5 secs, of pop-up target at 2 nm or less.
(8) Discriminate between threats separated by at least 1 nm in slant range.
The flight trial results and the 1998 OR(Air) document make it clear that the specification was met. Unfortunately, the programme was halted and with it the progress towards ALARP. Despite all the "smoke and mirrors" between 1998 and the time of the Moray Firth collision, the specification requirement was not fulfilled and the risk of collision remained NOT ALARP.
Currently, we are in the process of evaluating a piece of off the shelf equipment which falls short of the 1991 (ALARP) specification, and as a consequence the collision risk remains NOT ALARP. Probably that is the reason why the Risk Register shows no projected change in the Risk Index after TCAS has been fitted. It now seems a case of fitting any collision warning system simply to address the "societal concern".
N.B. This shold be read in conjunction with posting #250 "What is Tolerable"
DV
Last edited by Distant Voice; 12th Jul 2014 at 22:26. Reason: Addition
The flight trial results and the 1998 OR(Air) document make it clear that the specification was met. Unfortunately, the programme was halted and with it the progress towards ALARP.
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Is there any documentation which indicates why the programme was halted? For example, was the equipment (despite its apparently successful trial) deemed incapable of being integrated at reasonable cost?
The programme was costed and the the OR(Air) document states that "The maturity of the design and technology allows design to proceed straight into prototype/C model production". The ISD was given as 2004, which is in line with the 1998 SDR statement.
Perhaps the OR(Air) of the day will be able to give some sort of explanation at the FAI. I should add that that there were one or two big-hitters who were copied the 1998 OR (Air) document, including ACAS (Sir Jock Stirrup), and I of FS(RAF)
DV
Last edited by Distant Voice; 13th Jul 2014 at 18:32. Reason: addition
For example, was the equipment (despite its apparently successful trial) deemed incapable of being integrated at reasonable cost?
If you don't mind, I can answer.
The statement;
"The maturity of the design and technology allows design to proceed straight into prototype/C model production"
by definition means that the necessary Technology and System Integration Readiness Levels had been achieved, permitting the approving authority to sign for go ahead to launch production.
These two terms have changed a number of times over the years, but the meaning has remained constant; as directed by SofS based on advice from the Chief Scientific Advisor.
Regulations say that the overall TRL or SIRL for an aircraft or system defaults to the lowest TRL or SIRL. So, for example, on Chinook Mk2 in 1993, while much of the Mk2 was at TRL/SIRL 6 or 7 (necessary to achieve, in today's money, Main Gate), the FADEC Safety Critical Software was at no more than Level 3 (i.e. grossly immature, in fact "positively dangerous"), so the entire Mk2 defaulted to 3. This is a fundamental rule of programme management. That is, no (legal) RTS could exist, as there was no proper authority to even begin conversion. Hence, Boscombe's refusal to fly/ grounding.
In stating this in his submission to OR(RAF), the Staff Officer is confirming the programme is at the necessary maturity level. No Staff Officer would make such a Submission without first having drafts approved, if only because he would not wish to place a Star rank in the position of rejecting something he had already approved. Such prior approval, in this case to conduct a TDP, would have had an aim - to achieve a certain TRL/SIRL, or determine what TRL/SIRL extant technology was at. Confirmation that this had been achieved would already have been sougth and provided - not least because payment would depend on it.
Hope this helps.
ES:-
It had the misfortune to exist in H-C's 'Golden Period', as DV points out. You don't need to look much further than that, other than to identify who it was who pulled the plug on it
why the programme was halted?
Whilst in level flight in my 737 I experienced a resolution advisory with a tornado. Apart from the mandatory paperwork where I assessed the risk of collision as very low I was left with the impression that TCAS gave me better situation awareness than the tornado appeared to have as he crossed under me from left to right. We were VMC and ATC had warned me of the trafic. Nonetheless I was surprised by the event.
Possible TCAS on Tornados of non-Brit operators ?
Grüße Herr Lederhosen, das ist sehr interessant.
If I remember correctly from a long time ago, in order for a TCAS equipped aircraft to generate a Resolution Advisory (RA) the conflicting aircraft must also be TCAS equipped. If the conflicting aircraft is only transmitting IFF (squawking) the TCAS equipped aircraft will only generate a Traffic Advisory (TA.) The conflicting aircraft will know nothing except from ATC, eyeball or onboard radar.
In the case of the A319 and Tornado Airprox at Inverness Scotland, 20th April 2012 (See Distant Voice's Post 284) the A319 could only have generated a TA on the RAF Tornado – as the report confirms with the "traffic traffic" call. Even then, it requires the TCAS to detect an appropriate Squawk.
The difference roughly speaking between RA and TA – It is mandatory to follow a RA - If it says "Climb" you must climb. You would have some serious explaining to do if you did not follow an RA. It is not mandatory to take a specific action for a TA – because a TA will not include any manoeuvre instructions. If some other circumstance suggests action is required for a TA, such as turning away based on a visual, there is nothing to stop you taking it. Bear in mind that TCAS only issues height instructions – TCAS does not issue horizontal manoeuvre instructions.
For Lederhosen to experience a genuine RA on a Tornado, that suggests his particular Tornado was equipped with TCAS. Not Brit obviously, but perhaps German or Italian etc. The Tornado should therefore also have been aware of the 737 and received an RA via his own TCAS.
I am open to correction on any of the above.
Sofar I don't recollect seeing any mention of TCAS or CWS in relation to other Tornado operators. Perhaps they quietly got on with it years ago. This might spice up the current debate.
Does anyone have any info on possible TCAS or CWS equipment fitted to Tornados or other FJs of the Luftwaffe or other Air Forces ?
LFH
Whilst in level flight in my 737 I experienced a resolution advisory with a tornado. Apart from the mandatory paperwork where I assessed the risk of collision as very low I was left with the impression that TCAS gave me better situation awareness than the tornado appeared to have as he crossed under me from left to right. We were VMC and ATC had warned me of the trafic. Nonetheless I was surprised by the event.
If I remember correctly from a long time ago, in order for a TCAS equipped aircraft to generate a Resolution Advisory (RA) the conflicting aircraft must also be TCAS equipped. If the conflicting aircraft is only transmitting IFF (squawking) the TCAS equipped aircraft will only generate a Traffic Advisory (TA.) The conflicting aircraft will know nothing except from ATC, eyeball or onboard radar.
In the case of the A319 and Tornado Airprox at Inverness Scotland, 20th April 2012 (See Distant Voice's Post 284) the A319 could only have generated a TA on the RAF Tornado – as the report confirms with the "traffic traffic" call. Even then, it requires the TCAS to detect an appropriate Squawk.
The difference roughly speaking between RA and TA – It is mandatory to follow a RA - If it says "Climb" you must climb. You would have some serious explaining to do if you did not follow an RA. It is not mandatory to take a specific action for a TA – because a TA will not include any manoeuvre instructions. If some other circumstance suggests action is required for a TA, such as turning away based on a visual, there is nothing to stop you taking it. Bear in mind that TCAS only issues height instructions – TCAS does not issue horizontal manoeuvre instructions.
For Lederhosen to experience a genuine RA on a Tornado, that suggests his particular Tornado was equipped with TCAS. Not Brit obviously, but perhaps German or Italian etc. The Tornado should therefore also have been aware of the 737 and received an RA via his own TCAS.
I am open to correction on any of the above.
Sofar I don't recollect seeing any mention of TCAS or CWS in relation to other Tornado operators. Perhaps they quietly got on with it years ago. This might spice up the current debate.
Does anyone have any info on possible TCAS or CWS equipment fitted to Tornados or other FJs of the Luftwaffe or other Air Forces ?
LFH
Last edited by Lordflasheart; 14th Jul 2014 at 15:08. Reason: clarifications
Lord Flash,
Your memory has failed you; the quote below is from this Eurocontrol bulletin (see case study #3):
As far as I know there are no combat aircraft anywhere in the world fitted with TCAS (there are some fast-jet trainers that do have it now, e.g. Hawk T2 and Tucano). I think Tornado will be the first combat type. Some of the more modern ACMI pods have a collision warning function, but they only work cooperatively with similarly-equipped aircraft.
lederhosen,
I assume that congratulations are in order. Good game, great goal, very happy to see fellow Europeans on top! Anyway:
Very difficult to say what level of awareness that crew would have had. What airspace class were you in? If class E or G then it's most likely a case of the Tornado applying see and avoid, and misjudging the degree of separation required to prevent you receiving an RA. The only legal requirement on VFR aircraft in classes E and G is to avoid collision; there is no requirement to avoid other aircrafts' RA bubbles. It's good airmanship to do so, but it's very difficult to judge how much separation is required to avoid an RA. The only guaranteed way is to apply at least 1000ft vertical separation, which might not always be possible due to weather or adjacent controlled airspace. What looks 'close' to a 737 pilot may well look 'distant' to someone used to joining tankers, etc. Chances are, if you thought the risk was very low, they would have thought it non-existent.
Your memory has failed you; the quote below is from this Eurocontrol bulletin (see case study #3):
RAs are only coordinated between two TCAS equipped aircraft: If both aircraft are TCAS II equipped then the RAs are coordinated to ensure that manoeuvres are compatible. An RA can be generated against all altitude reporting aircraft (equipped with a Mode S or Mode A/C transponder) regardless of whether they carry TCAS.
lederhosen,
I assume that congratulations are in order. Good game, great goal, very happy to see fellow Europeans on top! Anyway:
Apart from the mandatory paperwork where I assessed the risk of collision as very low I was left with the impression that TCAS gave me better situation awareness than the tornado appeared to have as he crossed under me from left to right. We were VMC and ATC had warned me of the trafic.
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Some of the more modern ACMI pods have a collision warning function, but they only work cooperatively with similarly-equipped aircraft.
I understand that RAs will only be generated for aircraft above 1000 ft. Neither of the "Moray Firth" aicraft would have received one, had they been fitted with TCAS. On the other hand the bespoke equipment would have given a Threat Level II alert, as this was designed for the Fast Jet low level environment (200 - 5000 ft). See posting #313.
DV
Last edited by Distant Voice; 14th Jul 2014 at 17:17. Reason: Additional info
Not sure I understand your point DV? I expect most people would support a working bespoke FJ system, but why slag off TCAS? Basic TCAS would have provided traffic awareness. Surely your point should be that they were not even provided with TCAS, let alone a FJ optimised version.
OAP
OAP
DV,
I recommend study of the TCAS II specification before making posts which appear to imply that TCAS would have been of no use in the Moray accident, which is how I read your previous. TCAS gives Traffic Alerts at all heights. RAs with a descent component are suppressed below 1100ft radalt, while RAs with a climb component are suppressed above an altitude specified in type-specific software. All RAs are suppressed below 1000ft. This behaviour is all written in the TCAS standard. The Tornados would have known about each other's presence through TA had they been fitted with the equipment.
OAP,
DV is trying to show that even with TCAS on the way, the Tornado collision risk is not ALARP. Suggesting that TCAS would not have prevented the accident, either through ignorance of its function or deliberate omission of some basic facts, doesn't strike me as a particularly robust line of argument! Just as with RA 1210 a couple of pages ago, I've pointed him in the right direction for some corrective reading. Let's see where that takes us.
I recommend study of the TCAS II specification before making posts which appear to imply that TCAS would have been of no use in the Moray accident, which is how I read your previous. TCAS gives Traffic Alerts at all heights. RAs with a descent component are suppressed below 1100ft radalt, while RAs with a climb component are suppressed above an altitude specified in type-specific software. All RAs are suppressed below 1000ft. This behaviour is all written in the TCAS standard. The Tornados would have known about each other's presence through TA had they been fitted with the equipment.
OAP,
DV is trying to show that even with TCAS on the way, the Tornado collision risk is not ALARP. Suggesting that TCAS would not have prevented the accident, either through ignorance of its function or deliberate omission of some basic facts, doesn't strike me as a particularly robust line of argument! Just as with RA 1210 a couple of pages ago, I've pointed him in the right direction for some corrective reading. Let's see where that takes us.
Last edited by Easy Street; 15th Jul 2014 at 16:49.
Thank you for the correction and link, Easy Street - Re Post 320
I should have done my homework myself, instead of letting the dog do it for me. Apologies for my misleading post.
LFH
Lord Flash, Your memory has failed you; the quote below is from this Eurocontrol bulletin (see case study #3):
Quote:
RAs are only coordinated between two TCAS equipped aircraft: If both aircraft are TCAS II equipped then the RAs are coordinated to ensure that manoeuvres are compatible. An RA can be generated against all altitude reporting aircraft (equipped with a Mode S or Mode A/C transponder) regardless of whether they carry TCAS.
Quote:
RAs are only coordinated between two TCAS equipped aircraft: If both aircraft are TCAS II equipped then the RAs are coordinated to ensure that manoeuvres are compatible. An RA can be generated against all altitude reporting aircraft (equipped with a Mode S or Mode A/C transponder) regardless of whether they carry TCAS.
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But OAP is making the very good point that while a bespoke FJ TCAS would be great, holding out for the moon and stars may well leave us with nothing at all.
Re. your earlier response to Lederhosen, while it may not be a strict legal requirement to avoid an airliners TCAS bubble, not doing so without a good reason is surely inconsiderate and unprofessional? Even if he felt, as you charitably allowed, the risk was non-existent the tornado pilot ought to have considered the consequences of passing so close.
Re. your earlier response to Lederhosen, while it may not be a strict legal requirement to avoid an airliners TCAS bubble, not doing so without a good reason is surely inconsiderate and unprofessional? Even if he felt, as you charitably allowed, the risk was non-existent the tornado pilot ought to have considered the consequences of passing so close.
ShotOne,
I got what OAP was saying, thanks (and agree with it); I was trying to help him resolve his stated confusion at DV's rather misleading post.
As for avoiding the RA bubble, we're in violent agreement. I said it was good airmanship to avoid it, and explained why that is sometimes easier said than done. Did you read that bit?
I got what OAP was saying, thanks (and agree with it); I was trying to help him resolve his stated confusion at DV's rather misleading post.
As for avoiding the RA bubble, we're in violent agreement. I said it was good airmanship to avoid it, and explained why that is sometimes easier said than done. Did you read that bit?
Last edited by Easy Street; 15th Jul 2014 at 03:18.
A lot of this goes over my head but chug got it right in an earlier post. There are some who start attacking the individual if they don't like the facts. It doesn't help but says a lot.
What DV did was quote an entry in an MoD risk register which anticipated no projected change after TCAS has been fitted. Now you've pointed it out, will MoD change the register? That is the issue, not DV quoting what MoD claim.
Also, easy street, you floated the idea that CWS may be too expensive to integrate and tuc offered a reasonable answer (which I recognise from the Mull of Kintyre evidence.) I wonder if tuc's answer came as a surprise to anyone in MoD, which would explain a lot about why we are where we are.
I think we're losing sight of the thrust of the thread. Guys died and MoD told porkies about when the kit that may have prevented it could have been in the aircraft. A fatal accident inquiry is needed.
Suggesting that TCAS would not have prevented the accident, either through ignorance of its function or deliberate omission of some basic facts, doesn't strike me as a particularly robust line of argument!
Also, easy street, you floated the idea that CWS may be too expensive to integrate and tuc offered a reasonable answer (which I recognise from the Mull of Kintyre evidence.) I wonder if tuc's answer came as a surprise to anyone in MoD, which would explain a lot about why we are where we are.
I think we're losing sight of the thrust of the thread. Guys died and MoD told porkies about when the kit that may have prevented it could have been in the aircraft. A fatal accident inquiry is needed.
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Easy Street, what I said was;
What I did not say
What the SI reports says (1.4.4.129);
Correct. Because we are fitting a piece of civilian kit that was rejected back in 1991 due to its unsuitability for the FJ environment. This is supported by the SI report (1.4.4.109)
Furthermore, the Risk Register indicates that no risk reduction can be anticipated once TCAS II is fitted. A point that may have been lost on some people, but not Dervish. He sees the relevance of such a statement.
Onceapilot
You are correct, basic TCAS would have provided traffic awareness, and the SI report makes that quite clear. I am not slagging it off. The point I was trying to get across is that having identified the limitations of TCAS back in1991 a bespoke FJ collision warning system was successfully developed and flight tested. It was designed to operate at low level. Of course the RAIDS collision warning option could have been provided back in 2002, once someone decided not to go ahead with the bespoke system.
DV
I understand that RAs will only be generated for aircraft above 1000ft. Neither of the "Moray Firth" aircraft would have received one, had they been fitted with TCAS
What I did not say
TCAS would have been of no use in the Moray accident]
What the SI reports says (1.4.4.129);
ASTON 1 and ABBOT 2 would have been given a TA, 23 secs before impact and an audio warning. Neither oral nor visual alerts would have been generated, since both aircraft were below 1000 ft AGL (where the generation and announcement of RAs is suppressed by TCAS II logic).
DV is trying to show that even with TCAS on the way, the Tornado collision risk is not ALARP.
Correct. Because we are fitting a piece of civilian kit that was rejected back in 1991 due to its unsuitability for the FJ environment. This is supported by the SI report (1.4.4.109)
ACAS II has been designed for civil aircraft and the surveillance requirements are based on typical performance envelopes of such aircraft.........UK FJs routinely manoeuvre outside the design parameters
Furthermore, the Risk Register indicates that no risk reduction can be anticipated once TCAS II is fitted. A point that may have been lost on some people, but not Dervish. He sees the relevance of such a statement.
Onceapilot
Not sure I understand your point DV? I expect most people would support a working bespoke FJ system, but why slag off TCAS? Basic TCAS would have provided traffic awareness. Surely your point should be that they were not even provided with TCAS, let alone a FJ optimised version.
You are correct, basic TCAS would have provided traffic awareness, and the SI report makes that quite clear. I am not slagging it off. The point I was trying to get across is that having identified the limitations of TCAS back in1991 a bespoke FJ collision warning system was successfully developed and flight tested. It was designed to operate at low level. Of course the RAIDS collision warning option could have been provided back in 2002, once someone decided not to go ahead with the bespoke system.
DV