Air Cadets grounded?
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Sorry if I repeat myself here - but there's an important point that all pilots should understand.
You all have an absolute right to assume that the aircraft you sign for is airworthy. In a nutshell, that means that the assumption that it's safe to fly is based on a solid body of data and evidence that refers to the precise configuration of the aircraft you're flying. It also means that the aircraft has been properly maintained, modified and repaired throughout its life.
I repeat - you should not have to question this. But after seeing this shambles, if it's an Air Cadet glider, you should.
Ask to see the record of airframe repairs. Ask to see the register of Technical Instructions applied to the aircraft. Take a look at the Release to Service and have the engineers prove to you that the aircraft you are flying is exactly the same as the one specified in the RTS. If you're feeling fresh, ask who the ADA is. Or ask to see the latest Airworthiness Review.
You shouldn't have to do any of this. Your engineers might get grumpy. If they do, tell them "I'm doing this because you haven't been doing your job".
Oh, and don't accept any bromides such as: 'We were short of manpower because we had a problem with another aircraft', or 'The ATC was a bit of a backwater' or 'It was contracted out' or 'it was a corporate failure due to multiple reorganisations'. Get personal. Your engineer officers, every one of them, are officers in the Armed Forces who sign up to a code of ethics and assume professional responsibility in exchange for good pay - just like you. They are charged to do ANY job properly - just like you. They appear to have failed miserably at a basic core task.
Again, apologies for the tone here - I've thought this post through for a while, but I can't get past the extent of the RAF's failure to protect its aircrew, not to mention the civilian kids they were flying around. Like many who post on PPrune, I've done my share of funerals of young men. It's only the greatest good fortune that has prevented deaths in this case.
Best regards as ever to all those engineers looking after their pilots,
Engines
You all have an absolute right to assume that the aircraft you sign for is airworthy. In a nutshell, that means that the assumption that it's safe to fly is based on a solid body of data and evidence that refers to the precise configuration of the aircraft you're flying. It also means that the aircraft has been properly maintained, modified and repaired throughout its life.
I repeat - you should not have to question this. But after seeing this shambles, if it's an Air Cadet glider, you should.
Ask to see the record of airframe repairs. Ask to see the register of Technical Instructions applied to the aircraft. Take a look at the Release to Service and have the engineers prove to you that the aircraft you are flying is exactly the same as the one specified in the RTS. If you're feeling fresh, ask who the ADA is. Or ask to see the latest Airworthiness Review.
You shouldn't have to do any of this. Your engineers might get grumpy. If they do, tell them "I'm doing this because you haven't been doing your job".
Oh, and don't accept any bromides such as: 'We were short of manpower because we had a problem with another aircraft', or 'The ATC was a bit of a backwater' or 'It was contracted out' or 'it was a corporate failure due to multiple reorganisations'. Get personal. Your engineer officers, every one of them, are officers in the Armed Forces who sign up to a code of ethics and assume professional responsibility in exchange for good pay - just like you. They are charged to do ANY job properly - just like you. They appear to have failed miserably at a basic core task.
Again, apologies for the tone here - I've thought this post through for a while, but I can't get past the extent of the RAF's failure to protect its aircrew, not to mention the civilian kids they were flying around. Like many who post on PPrune, I've done my share of funerals of young men. It's only the greatest good fortune that has prevented deaths in this case.
Best regards as ever to all those engineers looking after their pilots,
Engines
All I can comment about is the situation on my squadron.
1 Night exercises; none in the last five years;
2 Gliding: (no comment);
3 Powered flying; our last session (the first this year) was binned the day before we were due to go. No reason given.........
Whether this is peculiar to our wing, or more widespread, I can't comment.
1 Night exercises; none in the last five years;
2 Gliding: (no comment);
3 Powered flying; our last session (the first this year) was binned the day before we were due to go. No reason given.........
Whether this is peculiar to our wing, or more widespread, I can't comment.
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Hi Arc
Also the way things 'played out' meant that there was no chance of any campaign/consultation to save any of the VGS's.
It is scandalous that nobody stepped in to oversee changes necessary to keep the gliders airworthy,but they just left it until it broke.It was a fashionable saying some years ago - sometimes you have to leave things until they are broken until you fix them ( I never bought into that myself).
The review that started in 2012 stated (something like) - any changes should have minimum impact on ACO flying - well that worked well.
I also believe they put the 'right' man in for the job (but that is my personal opinion).
Trouble is - in the usual MOD way - any attempt to save money usually ends up costing us lots !
As usual obviously there was no plan in place to replace the fleet,this could have been done in small batches over many years - but one should really have a fleet replacement plan - especially with gliders where the manufacturers capabilities are modest.
Also the way things 'played out' meant that there was no chance of any campaign/consultation to save any of the VGS's.
It is scandalous that nobody stepped in to oversee changes necessary to keep the gliders airworthy,but they just left it until it broke.It was a fashionable saying some years ago - sometimes you have to leave things until they are broken until you fix them ( I never bought into that myself).
The review that started in 2012 stated (something like) - any changes should have minimum impact on ACO flying - well that worked well.
I also believe they put the 'right' man in for the job (but that is my personal opinion).
Trouble is - in the usual MOD way - any attempt to save money usually ends up costing us lots !
As usual obviously there was no plan in place to replace the fleet,this could have been done in small batches over many years - but one should really have a fleet replacement plan - especially with gliders where the manufacturers capabilities are modest.
Edit: I said the RAF's fault, but actually I should have said everyone involved with airworthiness. I have no idea if they are all RAF, or ATC, etc.
Last edited by cats_five; 24th Nov 2016 at 07:43.
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Not sure that seeing the record of repairs will help since part of the problem is unrecorded repairs. If I send my glider for repairs / work I make darn sure the paperwork is in order when I get if back.
Have the gliders reached their maximum hours? I doubt it very much. The airworthiness problem is entirely of the RAF's making, and it seems to me is nothing at all to do with the age of the gliders beyond the people that f*cked up would have had less time to do so with new or newer gliders.
Also the 'airworthiness' aspect is only one part of this whole sorry tale,there is I am sure much more to it than that ! including the desire to close airfields/units as a 'cost saving' - as I posted previously this has been carried out in a devious way during the 'pause'.
By 'standard' gliders I mean unmodified by MOD/RAF
Longer ron
Correct. Every item in the inventory has a notional Out of Service Date from the day it is conceived. Every time you seek to spend money (but especially capital expenditure) you must be prepared to state this date, because financial rules prevent capital expenditure within 5 years of OSD, unless safety related. And even then, this safety caveat was removed in 1992/3 by AMSO, although ignored where possible by MoD(PE). This is directly linked to current problems.
Correct. Every item in the inventory has a notional Out of Service Date from the day it is conceived. Every time you seek to spend money (but especially capital expenditure) you must be prepared to state this date, because financial rules prevent capital expenditure within 5 years of OSD, unless safety related. And even then, this safety caveat was removed in 1992/3 by AMSO, although ignored where possible by MoD(PE). This is directly linked to current problems.
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Longer,
To add to Tuc's excellent point - there are often many good reasons for modifying a commercial design. Quite often, they are required to operate the design under military rules on the Military Aircraft Register.
Of course, that raises the point of why put ATC gliders on the Military Register at all. It was certainly a help when a previous CAS wanted to 'big up' RAF strength by including them as 'deployable aircraft'.
However, there should have been no problem whatsoever in bringing these aircraft on to the RAF's books. Any competent civil design authority would have already had a solid safety statement, plus the required certification evidence to allow the PT buying the kit to asses the extent of compliance with Def Stan 00-970 and to request the required modifications. Once these had been cleared by the DA, they would have formed part of the 'as contracted' configuration.
Once the aircraft were brought 'Under Ministry Control', the PT would have, as matter of normal course, been required to demonstrate compliance with the required regulations to the relevant MoD Committees and Boards. Part of this would have been the required PDS contracts and the mandated airworthiness reviews. The 'as contracted' configuration and its associated updated safety statement would have been the baseline for the RTS.
I stress again - all this would have been an utterly standard, well understood and quite easy process to do properly. Unfortunately, as Tuc and others have so well shown, RAF senior officers spent a good bit of the 1990s dismantling the experience base as well as the checks and balances that kept the show on the rails.
I agree that there have definitely been some fairly scummy politics around closure of many VGS sites. but the central issue (for me at least) is the RAF's failure to properly manage the airworthiness of their fleet of gliders. Why? Because there is absolutely nothing to stop this sort of c**p happening to other aircraft. In fact, I know that it is happening to other RAF aircraft right now.
That's a problem. A big one.
Best Regards as ever to all those good engineers out there trying to make the system work,
Engines
To add to Tuc's excellent point - there are often many good reasons for modifying a commercial design. Quite often, they are required to operate the design under military rules on the Military Aircraft Register.
Of course, that raises the point of why put ATC gliders on the Military Register at all. It was certainly a help when a previous CAS wanted to 'big up' RAF strength by including them as 'deployable aircraft'.
However, there should have been no problem whatsoever in bringing these aircraft on to the RAF's books. Any competent civil design authority would have already had a solid safety statement, plus the required certification evidence to allow the PT buying the kit to asses the extent of compliance with Def Stan 00-970 and to request the required modifications. Once these had been cleared by the DA, they would have formed part of the 'as contracted' configuration.
Once the aircraft were brought 'Under Ministry Control', the PT would have, as matter of normal course, been required to demonstrate compliance with the required regulations to the relevant MoD Committees and Boards. Part of this would have been the required PDS contracts and the mandated airworthiness reviews. The 'as contracted' configuration and its associated updated safety statement would have been the baseline for the RTS.
I stress again - all this would have been an utterly standard, well understood and quite easy process to do properly. Unfortunately, as Tuc and others have so well shown, RAF senior officers spent a good bit of the 1990s dismantling the experience base as well as the checks and balances that kept the show on the rails.
I agree that there have definitely been some fairly scummy politics around closure of many VGS sites. but the central issue (for me at least) is the RAF's failure to properly manage the airworthiness of their fleet of gliders. Why? Because there is absolutely nothing to stop this sort of c**p happening to other aircraft. In fact, I know that it is happening to other RAF aircraft right now.
That's a problem. A big one.
Best Regards as ever to all those good engineers out there trying to make the system work,
Engines
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As far as I know there is nothing to stop the Vikings going on the G-reg, except the problems that currently are preventing most of them from flying.
You mention replacements. The Vikings are fundamentally Grob G103A Twin II Acro gliders. Unfortunately I can't find what their lifespan, but for the K21 it is 12,000 hours which can now be extended to 18,000 hours. Where I fly they fly about 500 hours a year each, and we operate and instruct every day it's flyable except Xmas day. 12,000 hours has taken about 25 years to accumulate. I can't imagine the ATC gliders were flying anything like as many hours, I doubt their initial life was much different to the K21, so whilst the Vikings were built before 1989 I suspect they should have many hours left before needing life extension or cutting up, depending on if there is a suitable scheme of work for extension. Yes, thought is needed about replacing them, but there is no way they should need replacing for some years to come.
Does anyone know how many hours the Vikings usually have, and how many a year they might do?
You mention replacements. The Vikings are fundamentally Grob G103A Twin II Acro gliders. Unfortunately I can't find what their lifespan, but for the K21 it is 12,000 hours which can now be extended to 18,000 hours. Where I fly they fly about 500 hours a year each, and we operate and instruct every day it's flyable except Xmas day. 12,000 hours has taken about 25 years to accumulate. I can't imagine the ATC gliders were flying anything like as many hours, I doubt their initial life was much different to the K21, so whilst the Vikings were built before 1989 I suspect they should have many hours left before needing life extension or cutting up, depending on if there is a suitable scheme of work for extension. Yes, thought is needed about replacing them, but there is no way they should need replacing for some years to come.
Does anyone know how many hours the Vikings usually have, and how many a year they might do?
Once the aircraft were brought 'Under Ministry Control', the PT would have, as matter of normal course, been required to demonstrate compliance with the required regulations to the relevant MoD Committees and Boards.
I knew the mandated Defence Standard had been scrapped, but now read that DME500 (Design and Modification Engineering) does not mandate most of the actions necessary to maintain the build standard, which is a pre-requisite to a valid safety case. I now see why the Def Stan was cancelled. The 1993 AMSO policy to regard airworthinesss as optional, is now (unintentionally I hope) enshrined in some regulations. Time after time I thought – different people have contributed to this document, cutting and pasting various pieces, but there has been no proof reading or oversight that understands the linkages between the pieces.
While it and, for example, MAA02 (Glossary) mentions UMC, it doesn’t include the mandated procedures or even the checklist for achieving it. If you listed the problems with the gliders, alongside this checklist (which is two pages in the old Def Stan), you’d see the solution laid out in front of you. It isn’t long – 14 items. #8 requires the contractual arrangement for a valid safety case to be in place. It isn’t? No Release to Service. Item 11a requires the name, position and contact details of the individual responsible to be inserted in the contract (that comes into effect when the transfer meeting closes). The new regs don’t even require him to be present, so one wonders if anyone today is even trained to do the job. Item #7 is “Declaration of Hazards”. The first on my list would be the fact MoD is thinking of UMC, lacking a correct definition in the Glossary. (What it says is not actually wrong, but is akin to saying one maintains a car by checking the tyre pressure of your front off-side once a year).
“Achieved” is a key word, because UMC is a major achievement, warranting one of the biggest contractual milestone payments. Unsurprisingly, Westland’s entry in the Design Approved Organisation (Organization) Scheme document is the only one to mention UMC, confirming they are approved for “Modifications to aircraft that have achieved the status of UMC”. I’d actually be wary of employing anyone, company or individual, who didn’t understand this and didn’t trumpet such a high level approval. It is like saying you passed your 25 yard swimming certificate when 6 years old, but omitting that you’re now an Olympic gold medallist. It would surprise you how many well-known defence companies have never attained such an approval. However, I’m pleased the DAOS has survived, despite many years of political interference, with Defence Ministers insisting on major contracts being awarded to one man and his dog operations in their constituencies. Westland were major beneficiary, as we invariably went to them to dig out the favoured few.
I know, many are reading this thinking what a load of balls. But as Engines says, this is simple, basic stuff. So basic that few at an air station, and certainly no aircrew, ever see it happening. But it is money in the bank.
tuc:-
As an ex driver airframe I can appreciate that there is a sense amongst we two wing wonder gods that what Engines and tucumseh tell us is no doubt all true but is also rather esoteric arcane stuff, and life is too short to worry about it. I would strongly recommend reconsideration lest life become all too short, whether you drive gliders, helicopters, trainers, transports, or fast jets, etc!
I was blissfully unaware of how lucky I was that such a dedicated, experienced and knowledgeable team were watching my 6 o'clock when I served. I was indeed very lucky because that team isn't there anymore, they've been replaced by those who are inexperienced and lack knowledge, armed with a revised rule book that has replaced airworthiness maintenance with a tick box system that simply... ticks boxes.
So far the RAF has lost its ACO gliders, its Nimrods and its Sentries. You might note that none of them are core fleets for RAF operations, serving instead civilian youth, Royal Navy, and NATO commitments. The wagons are being drawn into ever tighter circles and pretty soon those core capabilities will be hit. Time is running out and the RAF needs to grasp this nettle, face up to the part that it has played in this scandal, and allow the return to full airworthiness of the UK military fleets by making Regulator and Investigator independent of it, the MOD, and each other.
Self Regulation doesn't work and in Aviation it Kills!
this is simple, basic stuff. So basic that few at an air station, and certainly no aircrew, ever see it happening. But it is money in the bank.
I was blissfully unaware of how lucky I was that such a dedicated, experienced and knowledgeable team were watching my 6 o'clock when I served. I was indeed very lucky because that team isn't there anymore, they've been replaced by those who are inexperienced and lack knowledge, armed with a revised rule book that has replaced airworthiness maintenance with a tick box system that simply... ticks boxes.
So far the RAF has lost its ACO gliders, its Nimrods and its Sentries. You might note that none of them are core fleets for RAF operations, serving instead civilian youth, Royal Navy, and NATO commitments. The wagons are being drawn into ever tighter circles and pretty soon those core capabilities will be hit. Time is running out and the RAF needs to grasp this nettle, face up to the part that it has played in this scandal, and allow the return to full airworthiness of the UK military fleets by making Regulator and Investigator independent of it, the MOD, and each other.
Self Regulation doesn't work and in Aviation it Kills!
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"As far as I know there is nothing to stop the Vikings going on the G-reg, except the problems that currently are preventing most of them from flying.
You mention replacements. The Vikings are fundamentally Grob G103A Twin II Acro gliders. Unfortunately I can't find what their lifespan, but for the K21 it is 12,000 hours which can now be extended to 18,000 hours. Where I fly they fly about 500 hours a year each, and we operate and instruct every day it's flyable except Xmas day. 12,000 hours has taken about 25 years to accumulate. I can't imagine the ATC gliders were flying anything like as many hours, I doubt their initial life was much different to the K21, so whilst the Vikings were built before 1989 I suspect they should have many hours left before needing life extension or cutting up, depending on if there is a suitable scheme of work for extension. Yes, thought is needed about replacing them, but there is no way they should need replacing for some years to come.
Does anyone know how many hours the Vikings usually have, and how many a year they might do?"
Vikings have been operated at over their civil max weight for some time (based on what justification?), and so would probably be difficult to transfer to the civil register. I believe a civil G103 has a life of 12,000 hours, with major inspections every 3,000. However a Viking has a life of only 27,000 launches (again based on what justification?) - perhaps only 2,500 hours. I'm guessing most Vikings are around the 2,000 hour mark? The question to ask is why have the differences to the civil certification been approved?
Phil
You mention replacements. The Vikings are fundamentally Grob G103A Twin II Acro gliders. Unfortunately I can't find what their lifespan, but for the K21 it is 12,000 hours which can now be extended to 18,000 hours. Where I fly they fly about 500 hours a year each, and we operate and instruct every day it's flyable except Xmas day. 12,000 hours has taken about 25 years to accumulate. I can't imagine the ATC gliders were flying anything like as many hours, I doubt their initial life was much different to the K21, so whilst the Vikings were built before 1989 I suspect they should have many hours left before needing life extension or cutting up, depending on if there is a suitable scheme of work for extension. Yes, thought is needed about replacing them, but there is no way they should need replacing for some years to come.
Does anyone know how many hours the Vikings usually have, and how many a year they might do?"
Vikings have been operated at over their civil max weight for some time (based on what justification?), and so would probably be difficult to transfer to the civil register. I believe a civil G103 has a life of 12,000 hours, with major inspections every 3,000. However a Viking has a life of only 27,000 launches (again based on what justification?) - perhaps only 2,500 hours. I'm guessing most Vikings are around the 2,000 hour mark? The question to ask is why have the differences to the civil certification been approved?
Phil
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Vikings have been operated at over their civil max weight for some time (based on what justification?), and so would probably be difficult to transfer to the civil register. I believe a civil G103 has a life of 12,000 hours, with major inspections every 3,000. However a Viking has a life of only 27,000 launches (again based on what justification?) - perhaps only 2,500 hours. I'm guessing most Vikings are around the 2,000 hour mark? The question to ask is why have the differences to the civil certification been approved?
Are you absolutely sure it's the actual Vikings that have the launch limitation, or was it the hook? Got any documentation backing that up? It's a totally bizarre requirement if it's true.
Tost release hooks need an overhaul every 10,000 actuations which is less than ever 10,000 flights depending on how the actuations are counted. 5 per flight is common - 3 checks (back release, free drop, release under tension) plus 1 for launch and the release at the end of the launch.
http://wingsandwheels.com/media/wysi...lisch_2001.pdf
A life of 27,000 launches when the primary use is circuits off a winch is not very long at all. The average flight time for one of our K21s, at a hill soaring site, is 15.62 minutes. At a non-hill soaring site I would expect it to be less.
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Cats
There was a specific programme of stress testing carried out on a Viking airframe at Swanton Morley as part of the entry into service - 1 airframe was sacrificed on a test jig/rig.
What the outcome was I am unsure but this cyclic testing led to the introduction of 27000 launches life. Since I would suggest that an average Viking probably does no more than 500 launches a year - we're probably only approx. halfway to that figure..................
Note that comparing a K21 and Grob 103 is not 'apples with apples' as the design and construction methods are very different. Therefore the fatigue life will be different.
Finally I am unaware that the Viking is operating overweight. I've not seen that documented anywhere. Since they are military aircraft the BGA dispensation is irrelevant anyway (even though the aircraft do have BGA numbers !). Actually some of the aircraft differ radically in weight (empty) as they have had various repairs and various schemes applied. It should be noted that the ones based at coastal airfields weigh more than those based more inland by a fair few kilos so apply a blanket comment about overweight is a bit broad brush !!
Note that it's 33 months now since the pause..........................and counting
Arc
There was a specific programme of stress testing carried out on a Viking airframe at Swanton Morley as part of the entry into service - 1 airframe was sacrificed on a test jig/rig.
What the outcome was I am unsure but this cyclic testing led to the introduction of 27000 launches life. Since I would suggest that an average Viking probably does no more than 500 launches a year - we're probably only approx. halfway to that figure..................
Note that comparing a K21 and Grob 103 is not 'apples with apples' as the design and construction methods are very different. Therefore the fatigue life will be different.
Finally I am unaware that the Viking is operating overweight. I've not seen that documented anywhere. Since they are military aircraft the BGA dispensation is irrelevant anyway (even though the aircraft do have BGA numbers !). Actually some of the aircraft differ radically in weight (empty) as they have had various repairs and various schemes applied. It should be noted that the ones based at coastal airfields weigh more than those based more inland by a fair few kilos so apply a blanket comment about overweight is a bit broad brush !!
Note that it's 33 months now since the pause..........................and counting
Arc
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Arc,
I'd be genuinely interested to know how a 'programme of stress testing' was carried out at (presumably) RAF Swanton Morley.
Apart from the technical aspects of how any 'stress testing' was devised on a composite airframe, and how it was applied, whether ultimate stress tests were carried out, the standard of the airframe selected, etc., the big question for me would be why this work wasn't carried out by the aircraft DA?
Oh, and what technical authority (and certification) did RAF Swanton Morley have to carry out such testing? And what was the DA's involvement in the testing? Who approved the 'cyclic' test profiles? And why was it necessary? Were the RAF planning to operate the aircraft outside its existing certified usage spectrum and/or configuration that underpinned the existing safety statement? Who approved the resultant 27,000 launch life? What fatigue monitoring and airframe inspection programme was put in place to follow on from this 'in house' 'stress testing'?
Updated - a subsequent post (thanks Why oh why) appears to confirm that the RAF are operating the aircraft at an increased MAUW (625 Kg versus 580 or 597 with a 'BGA uplift'). So is there documentation (and DA approval) for that? What's urgently needed is sone transparency here. This isn't a 'national security' matter - the ATC is a 'youth organisation' paid for by the RAF (i.e. us) and they have already admitted that they have had airworthiness 'challenges'. Time to find out what these were.
Best regards as ever to all those clever fatigue testing people,
Engines
I'd be genuinely interested to know how a 'programme of stress testing' was carried out at (presumably) RAF Swanton Morley.
Apart from the technical aspects of how any 'stress testing' was devised on a composite airframe, and how it was applied, whether ultimate stress tests were carried out, the standard of the airframe selected, etc., the big question for me would be why this work wasn't carried out by the aircraft DA?
Oh, and what technical authority (and certification) did RAF Swanton Morley have to carry out such testing? And what was the DA's involvement in the testing? Who approved the 'cyclic' test profiles? And why was it necessary? Were the RAF planning to operate the aircraft outside its existing certified usage spectrum and/or configuration that underpinned the existing safety statement? Who approved the resultant 27,000 launch life? What fatigue monitoring and airframe inspection programme was put in place to follow on from this 'in house' 'stress testing'?
Updated - a subsequent post (thanks Why oh why) appears to confirm that the RAF are operating the aircraft at an increased MAUW (625 Kg versus 580 or 597 with a 'BGA uplift'). So is there documentation (and DA approval) for that? What's urgently needed is sone transparency here. This isn't a 'national security' matter - the ATC is a 'youth organisation' paid for by the RAF (i.e. us) and they have already admitted that they have had airworthiness 'challenges'. Time to find out what these were.
Best regards as ever to all those clever fatigue testing people,
Engines
Last edited by Engines; 15th Dec 2016 at 10:44. Reason: Update
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The Twin 2 Acro is operating on the BGA registry at a MAUW of either 580kg or 597kg with the BGA 3% uplift.
The Viking is operating at a MAUW of 625kg.
On my VGS the typical use of the airframes was approx 20-22k launches each. This is pretty much fleet average
The Viking is operating at a MAUW of 625kg.
On my VGS the typical use of the airframes was approx 20-22k launches each. This is pretty much fleet average
"Tost release hooks need an overhaul every 10,000 actuations which is less than ever 10,000 flights depending on how the actuations are counted. 5 per flight is common - 3 checks (back release, free drop, release under tension) plus 1 for launch and the release at the end of the launch."
Really? You check the hook every launch?
Really? You check the hook every launch?
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Hi
Engines
Can't answer many of the questions I'm afraid - I only flew the end product
The Airframe was brand new, and the jig was set up to repeat multiple cycles of the stress loadings from winch launch cycles as I recall. There was a test rig and Hydraulic jacks which did the flexing and unflexing of components. I saw it only once on a visit to Swanton.
The cycle life was issued by Swanton at the end of the testing. I can only assume that the DT and NDT teams agreed the 27000 launch limit - based on what I am not sure.............. I don't believe that a follow on fatigue programme was in place although obviously usage figures were monitored across the fleet and some balancing undertaken.
and yes - surely the DA should have undertaken this..........
WOW
That figure of around 20,000 launches seems pretty much in line with what my VGS had on their aircraft. As there were more spare Vikings towards the end the balancing of hours across the fleet was a lot easier.
Also the Viking is not a Twin 2 Acro. The Acro has a different wing section. The nearest to the Viking 'off the shelf' would be a Grob 103b.
Thud
We test the hook every day - not every launch, then use it every launch
Hope this helps
Arc
Engines
Can't answer many of the questions I'm afraid - I only flew the end product
The Airframe was brand new, and the jig was set up to repeat multiple cycles of the stress loadings from winch launch cycles as I recall. There was a test rig and Hydraulic jacks which did the flexing and unflexing of components. I saw it only once on a visit to Swanton.
The cycle life was issued by Swanton at the end of the testing. I can only assume that the DT and NDT teams agreed the 27000 launch limit - based on what I am not sure.............. I don't believe that a follow on fatigue programme was in place although obviously usage figures were monitored across the fleet and some balancing undertaken.
and yes - surely the DA should have undertaken this..........
WOW
That figure of around 20,000 launches seems pretty much in line with what my VGS had on their aircraft. As there were more spare Vikings towards the end the balancing of hours across the fleet was a lot easier.
Also the Viking is not a Twin 2 Acro. The Acro has a different wing section. The nearest to the Viking 'off the shelf' would be a Grob 103b.
Thud
We test the hook every day - not every launch, then use it every launch
Hope this helps
Arc