CASA $1,000 Useless Compass Check
On 14 January 1962 James Knight commenced a flight from Ceduna, South Australia to Cook, South Australia in Wackett VH-BEC (ex-RAAF A3-139). He was never seen again. Over three years later, on 28 March 1965, VH-BEC was found by chance two hundred miles North of Cook. Knight had remained with the aircraft after it force-landed and inscribed a diary and his Last Will and Testament on the fuselage panels; the last diary entry was made on 20 January 1962. It was subsequently determined that the mount of the magnetic compass was loose and displayed headings that were 30 degrees in error.
Must be something in the water at Ceduna. Chap departed for a NVFR flight to Whyalla and ended up over Woomera due compass misreading - metallic object placed on glareshield, seem to recall it was the metal rings in the publications.
Beaufighter has an interesting note - Firing the 20mm guns causes a compass deviation. Deviation may be restored to the values on the compass card by firing a one second burst while flying level on compass north. This should be done at the first opportunity, and in any case before landing.
Must be something in the water at Ceduna. Chap departed for a NVFR flight to Whyalla and ended up over Woomera due compass misreading - metallic object placed on glareshield, seem to recall it was the metal rings in the publications.
Beaufighter has an interesting note - Firing the 20mm guns causes a compass deviation. Deviation may be restored to the values on the compass card by firing a one second burst while flying level on compass north. This should be done at the first opportunity, and in any case before landing.
I knew that would confuse you Creamie, 3 questions and not one answered.
If you believe that the scenario I gave would not present a potential problem, then ,hint, the answer is no, end of story. As for picking on factory aircraft, I'm not, it just so happens that the 2 I singled out were factory aircraft Did I suggest that that maintenance organisations don't make mistakes? (oops, another question.), well I'll answer that one for you, NO.
Seems to be fairly sensible to me.
If you believe that the scenario I gave would not present a potential problem, then ,hint, the answer is no, end of story. As for picking on factory aircraft, I'm not, it just so happens that the 2 I singled out were factory aircraft Did I suggest that that maintenance organisations don't make mistakes? (oops, another question.), well I'll answer that one for you, NO.
All the talk about unnecessary maitanence would have some merit if these checks were being done and no defects were being found. The facts are that defects are being found, serious ones at that. Isn't that the point of these test?
Dick is absolutely right - regular compass swings are a waste of good money better spent elsewhere. Good gyros, for example. Or a backup GPS.
Those crazy Canucks flying close to the magnetic pole have never been able to rely on magnetic compass. In pre GPS days the drill was to align the DG with the runway before take off then reset it at approximately 15 minute intervals by calculating precession. In summer this could be assisted by using a pelorus, but in winter darkness a whole flight of several hours could be done simply by estimating precession and having a rough idea of which stars were what. Amazingly, even with limited ground Nav aids and all the nasty effects on NDB reception at those latitudes, pilots rarely got lost. Some of that classroom theory actually did have a purpose.
Which makes the point - pre GPS we could and did fly in some places without a compass, so surely we can live with one with a small air bubble in it, or a few degrees out. Just so long as we keep track of its errors.
The unfortunate loss of the Wacket on the Nullabor was not entirely due to compass error, though because the pilot was unaware of it, it certainly contributed.
Those crazy Canucks flying close to the magnetic pole have never been able to rely on magnetic compass. In pre GPS days the drill was to align the DG with the runway before take off then reset it at approximately 15 minute intervals by calculating precession. In summer this could be assisted by using a pelorus, but in winter darkness a whole flight of several hours could be done simply by estimating precession and having a rough idea of which stars were what. Amazingly, even with limited ground Nav aids and all the nasty effects on NDB reception at those latitudes, pilots rarely got lost. Some of that classroom theory actually did have a purpose.
Which makes the point - pre GPS we could and did fly in some places without a compass, so surely we can live with one with a small air bubble in it, or a few degrees out. Just so long as we keep track of its errors.
The unfortunate loss of the Wacket on the Nullabor was not entirely due to compass error, though because the pilot was unaware of it, it certainly contributed.
Getting out of bed in the morning creates “potential problems”, Arnold.
I agree completely: It is ostensibly sensible.
Whether it is, in fact, sensible, is a related but different question.
What caused the defects? What objective risks did the defects create? What is the cost of dealing with that risk? Does that cost outweigh the potential consequences? Does the way of dealing with the risk cause more problems than it resolves?
For a maintainer, maintenance never causes defects. However, an objective analysis of the data shows that maintenance not only sometimes causes defects, but that more maintenance more often always causes more defects.
Maintainers don’t know – because they can’t know - what objective risks arise from an inaccurate compass, ASI or altimeter. It’s just assumed that because it’s mandated and defects are found, the risks must justify the mandate. It’s completely circular.
Megan: Pilots get lost with perfectly serviceable instruments providing perfectly accurate indications. What conclusions should we draw from that fact and the examples you provided?
All the talk about unnecessary maitanence would have some merit if these checks were being done and no defects were being found. The facts are that defects are being found, serious ones at that. Isn't that the point of these test?
Arnold E: Seems to be fairly sensible to me.
Arnold E: Seems to be fairly sensible to me.
Whether it is, in fact, sensible, is a related but different question.
What caused the defects? What objective risks did the defects create? What is the cost of dealing with that risk? Does that cost outweigh the potential consequences? Does the way of dealing with the risk cause more problems than it resolves?
For a maintainer, maintenance never causes defects. However, an objective analysis of the data shows that maintenance not only sometimes causes defects, but that more maintenance more often always causes more defects.
Maintainers don’t know – because they can’t know - what objective risks arise from an inaccurate compass, ASI or altimeter. It’s just assumed that because it’s mandated and defects are found, the risks must justify the mandate. It’s completely circular.
Megan: Pilots get lost with perfectly serviceable instruments providing perfectly accurate indications. What conclusions should we draw from that fact and the examples you provided?
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For a maintainer, maintenance never causes defects. However, an objective analysis of the data shows that maintenance not only sometimes causes defects, but that more maintenance more often always causes more defects.
Can you point me to a study of this? So you are saying I shouldn't get my car serviced? Extraordinary claims require extraordinary evidence
Next time I see a compass without (read that nil) any fluid. Should I not touch it in case I create more issues ?
What caused the defects?
An old operator once told me that you should leave a pilot with one aircraft. If you swap them around they find defects. If left they are accustomed to the faults they live with them. It is akin to a dripping tap in your house.
Psychology of pilots is fascinating. The Garmin trainer pointed out Pavlovian responses in pilots once . Since then I always chuckle when I see them displayed.
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CAStApo vs Anarchy
As much as I believe that the CAStApo and their political masters are out of control, there a lot of people in this thread throwing out the baby with the bath water. The great majority of GA aircraft are tooling around the sky with primitive out of date technology that in my view is highly unreliable.
I have little to no sympathy for the uber rich whining about their operating costs on multi million dollar helicopters which by the way Eddy Dean I have never signed for a compass swing on and don't intend to. Only the foolish operate a machine with so many critical moving parts. Live in that world and pay the price. On a fixed wing aircraft (read sensible practical and RELATIVELY economical) I can achieve a compass swing within .5 of an hour with two mechanics or about $100 bucks, which in the big picture is small change. What the pilot does with that after he/she leaves is of zero interest to me.
The instruments should be calibrated just like a torque wrench or any other tool that we ask for a constant and predictable measure. This is a basic foundation in the science that has evolved into the ability to defy gravity safely. The ASI, Altimeter and VSI provide information far more critical than the compass. I am firmly with Hasherufc and Arnold E on this one and I am somewhat bemused that the more learned among us are effectively promoting anarchy on the instrument panel as a method of questioning the CAStApo's regulatory shortcomings.
Gentleman, your effort would be better spent questioning why the whole country is going down the gurgler or why aviation is an ever increasing extortion racket. The CAStApo are a symptom not the cause. Unless the battle is fought on a political level you will continue to suffer from bizzare regulatory conditions, far removed from and infinitely more toxic than a simple instrument calibration.
I have little to no sympathy for the uber rich whining about their operating costs on multi million dollar helicopters which by the way Eddy Dean I have never signed for a compass swing on and don't intend to. Only the foolish operate a machine with so many critical moving parts. Live in that world and pay the price. On a fixed wing aircraft (read sensible practical and RELATIVELY economical) I can achieve a compass swing within .5 of an hour with two mechanics or about $100 bucks, which in the big picture is small change. What the pilot does with that after he/she leaves is of zero interest to me.
The instruments should be calibrated just like a torque wrench or any other tool that we ask for a constant and predictable measure. This is a basic foundation in the science that has evolved into the ability to defy gravity safely. The ASI, Altimeter and VSI provide information far more critical than the compass. I am firmly with Hasherufc and Arnold E on this one and I am somewhat bemused that the more learned among us are effectively promoting anarchy on the instrument panel as a method of questioning the CAStApo's regulatory shortcomings.
Gentleman, your effort would be better spent questioning why the whole country is going down the gurgler or why aviation is an ever increasing extortion racket. The CAStApo are a symptom not the cause. Unless the battle is fought on a political level you will continue to suffer from bizzare regulatory conditions, far removed from and infinitely more toxic than a simple instrument calibration.
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So Creampuff I spent about 2 hours researching researching the "Waddington Effect" and honestly I didn't find much. Most seems to come back to AOPA pages and Sports Aviation Webpages. The same article Written by Mike Busch.
EAA Sport Aviation - March 2011
EAA Sport Aviation - March 2011
and this article which is half plagiarised from wikipedia
The Waddington Effect « Opinion Leaders
http://cmapspublic.ihmc.us/rid=1HTKPYHY3-10D9MZ0-11ML/
Mike seems to have got his idea for this piece from a little history lesson article by Dr James Ignizio from the University of Texas. Dr James doesn't seem to any citations expect this paper
C. H. Waddington. "O. R. in World War 2: Operational Research against the U-boat", Elek Science, London, 1973.
Where its claimed that submarines are 20% less visible if painted white. Strangely they are still black now.
Wikipeda doesn't offer any clue to his CH Wallington war time activity's.
A Book : Cognitive Biology: Dealing with Information from Bacteria to Minds
By Gennaro Auletta Refers to the WaddingTon effect in Biological terms
The major claim seems to be:
Of course this could be true but be careful with cause and effect..
So the only modern (post 1970's) reference I could find was in a MIT paper. Unfortunately the context of the paper is unclear.
http://ocw.mit.edu/courses/engineeri...event_main.pdf
It states "Impact of Waddington Effect = 1.4% Availability"
So your statement of
seems nonsensical if it affects availability by 1.4%.
I wanted to find more. Hard facts!! But we are comparing a wartime environment to a Sigma Six environment. Many people in the war time environment would have been trained in a rush and working in adverse conditions. Now we have rules for maintenance hangars.
Okay that was thread drift but interesting bit of reading
EAA Sport Aviation - March 2011
EAA Sport Aviation - March 2011
and this article which is half plagiarised from wikipedia
The Waddington Effect « Opinion Leaders
http://cmapspublic.ihmc.us/rid=1HTKPYHY3-10D9MZ0-11ML/
Mike seems to have got his idea for this piece from a little history lesson article by Dr James Ignizio from the University of Texas. Dr James doesn't seem to any citations expect this paper
C. H. Waddington. "O. R. in World War 2: Operational Research against the U-boat", Elek Science, London, 1973.
Where its claimed that submarines are 20% less visible if painted white. Strangely they are still black now.
Wikipeda doesn't offer any clue to his CH Wallington war time activity's.
A Book : Cognitive Biology: Dealing with Information from Bacteria to Minds
By Gennaro Auletta Refers to the WaddingTon effect in Biological terms
The major claim seems to be:
Once these recommendations were implemented, the number of effective flying hours of the RAF Coastal Command bomber fleet increased by 60 percent!
So the only modern (post 1970's) reference I could find was in a MIT paper. Unfortunately the context of the paper is unclear.
http://ocw.mit.edu/courses/engineeri...event_main.pdf
It states "Impact of Waddington Effect = 1.4% Availability"
So your statement of
For a maintainer, maintenance never causes defects. However, an objective analysis of the data shows that maintenance not only sometimes causes defects, but that more maintenance more often always causes more defects.
I wanted to find more. Hard facts!! But we are comparing a wartime environment to a Sigma Six environment. Many people in the war time environment would have been trained in a rush and working in adverse conditions. Now we have rules for maintenance hangars.
Okay that was thread drift but interesting bit of reading
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although I rarely use them I check my instruments every flight.
the altimeter is set to airfield height by tweaking the QNH.
after a flight typically for an hour or more and altitudes up to 6000ft I return and land. the altimeter on the taxy back is reading the airfield height.
I'd say it was working satisfactorily.
occasionally I check my stall speed. 42 knots indicated. bang on the money every time. now I know that there is a 10 knot instrument setup error and I am actually stalling at 52 knots but that doesn't matter. I fly circuit speeds on the indicated speeds. in cruise I use a gps anyway. at 120 knots the error is 1 knot.
I never use my magnetic compass ever. I check it on the lineup every few months and if the leg is long and the air stable I compare it to the gps.
it hasn't been out in over 10 years.
to assume that aircraft are being flown with wildly inaccurate and never checked instruments is nonsense. they get checked all the time by pilots.
one of the things never mentioned in the race to deride old technology is that aircraft instruments are of the highest quality ever made. they are not shonky items. why would an instrument made to such quality go out of adjustment?
mine don't.
the wackett fatality had nothing to do with the compass in reality.
the pilot assumed that he would see the transcontinental railway line and be able to turn for forrest.
I took a photo on one of my flights in the position where he crossed the railway.
in the afternoon light, even when you know where the railway is, it is impossible to see it. a salutary warning for pilots flying pilotage in the gafa.
the gravel ballast is the same colour as the surrounds and the actual rails are only 4 inches wide. unless you get the shine on the rails they are invisible.
the altimeter is set to airfield height by tweaking the QNH.
after a flight typically for an hour or more and altitudes up to 6000ft I return and land. the altimeter on the taxy back is reading the airfield height.
I'd say it was working satisfactorily.
occasionally I check my stall speed. 42 knots indicated. bang on the money every time. now I know that there is a 10 knot instrument setup error and I am actually stalling at 52 knots but that doesn't matter. I fly circuit speeds on the indicated speeds. in cruise I use a gps anyway. at 120 knots the error is 1 knot.
I never use my magnetic compass ever. I check it on the lineup every few months and if the leg is long and the air stable I compare it to the gps.
it hasn't been out in over 10 years.
to assume that aircraft are being flown with wildly inaccurate and never checked instruments is nonsense. they get checked all the time by pilots.
one of the things never mentioned in the race to deride old technology is that aircraft instruments are of the highest quality ever made. they are not shonky items. why would an instrument made to such quality go out of adjustment?
mine don't.
the wackett fatality had nothing to do with the compass in reality.
the pilot assumed that he would see the transcontinental railway line and be able to turn for forrest.
I took a photo on one of my flights in the position where he crossed the railway.
in the afternoon light, even when you know where the railway is, it is impossible to see it. a salutary warning for pilots flying pilotage in the gafa.
the gravel ballast is the same colour as the surrounds and the actual rails are only 4 inches wide. unless you get the shine on the rails they are invisible.
So Creampuff I spent about 2 hours researching researching the "Waddington Effect" and honestly I didn't find much.
Must try harder.
The RAF discovered that continually fixing things that ain't broke quite severely reduced aircraft availability, and significantly, maintenance induced defects were a major contributor.
What the RAF discovered, refined and developed over the years, we would now call "on condition" maintenance.
The nearest Qantas ever came to losing an aircraft in flight (and I am thinking of two serious incidents, one a DC-4, the other a B707-338C) were maintenance error defects.
"Back in the day" I have taken quite a few aircraft on their first trip "out of the hangar". You expect to find defects, and are seldom disappointed. Some were really serious, ( keepers left off aileron pulleys, cable came off the pulley, as just one example, I could go on. Those of us with enough time under our belt all know that the first 10 hours "out of the shed" after a major inspection can be very interesting.
The whole point of what Dick and Creamie are saying is that much of the approach to GA maintenance in Australia allows little room for common sense, the framework of the law makes us all criminals, just some of us haven't been caught yet. And it maximizes cost, for no safety benefit, let alone a positive benefit/cost.
It is almost never "evidence based" maintenance.
Tootle pip!!
PS: Anybody remember the CASA rules for compass swinging about 2003, that were rapidly dropped? This was "how to do it", not "when to do it". The first "concession" was for the QF B747 and B767, a big enough compass base didn't exist, anywhere in the world, to do what CASA proposed to impose. The clown who wrote the CAO had never heard of a landing compass, and the order was substantially about building a compass base with brass plugs around the perimeter, surveyed to denote the cardinal points. Perhaps the most absurd, of many absurd things produced by CASA over the years.
So I think you have your answer, Dick.
A country whose GA fleet is mere rounding errors on the size and hours amassed in the USA knows better. You should feel comforted by the fact that your helicopter will be 'safer' in Australia.
If you fly your helicopter past the date on which the compass has to be calibrated, without having it calibrated, you'd be a dangerous criminal even if it remained accurate. However, if the calibrated compass suffered a random failure in flight, you're safe because the compass had been calibrated.
You see: It's all about 'safety'.
A country whose GA fleet is mere rounding errors on the size and hours amassed in the USA knows better. You should feel comforted by the fact that your helicopter will be 'safer' in Australia.
If you fly your helicopter past the date on which the compass has to be calibrated, without having it calibrated, you'd be a dangerous criminal even if it remained accurate. However, if the calibrated compass suffered a random failure in flight, you're safe because the compass had been calibrated.
You see: It's all about 'safety'.
Last edited by Creampuff; 12th Jan 2015 at 20:28.
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The RAF discovered that continually fixing things that ain't broke quite severely reduced aircraft availability, and significantly, maintenance induced defects were a major contributor.
What the RAF discovered, refined and developed over the years, we would now call "on condition" maintenance.
What the RAF discovered, refined and developed over the years, we would now call "on condition" maintenance.
The nearest Qantas ever came to losing an aircraft in flight (and I am thinking of two serious incidents, one a DC-4, the other a B707-338C) were maintenance error defects.
"Back in the day" I have taken quite a few aircraft on their first trip "out of the hangar". You expect to find defects, and are seldom disappointed. Some were really serious, ( keepers left off aileron pulleys, cable came off the pulley, as just one example, I could go on. Those of us with enough time under our belt all know that the first 10 hours "out of the shed" after a major inspection can be very interesting.
I really think you are comparing apples with oranges on the study. To which I am yet to find the original attributable source. In the book "The Ravens" it is mentioned that the Cessna Birddogs were unreliable. Until command changed from B-52 engineers to engineers who had worked on type. Could it just be that in 1941 they didn't have enough trained staff to service aircraft ??
Reliability Centered Maintenance
As a former aircraft engineer, current pilot and aircraft owner I am firmly with Creampuff on this one.
More damage has been done to my Cessna by engineers pulling it apart to do inspections than has been found by the inspections.
RCM is what should be used and in a way has been in Schedule 5 however that was based on post war aircraft not on later american manufactured machines.
The key with RCM is continuous review. There is a lot of scientific literature on the use of RCM to manage complex systems.
More damage has been done to my Cessna by engineers pulling it apart to do inspections than has been found by the inspections.
RCM is what should be used and in a way has been in Schedule 5 however that was based on post war aircraft not on later american manufactured machines.
The key with RCM is continuous review. There is a lot of scientific literature on the use of RCM to manage complex systems.
the altimeter is set to airfield height by tweaking the QNH.
after a flight typically for an hour or more and altitudes up to 6000ft I return and land. the altimeter on the taxy back is reading the airfield height.
after a flight typically for an hour or more and altitudes up to 6000ft I return and land. the altimeter on the taxy back is reading the airfield height.
Interesting read..
Flight into Nowhere. regarding the lost Wackett tragedy.
Apart from not spotting the iron rail..due visiblity or being well before expected eta for intercept time, due to the compass error, he ploughed on.
And the error was caused by; vibrating loose during the journey from Melbourne or some magnetic item interfering. The booklet states there was a reading difference in the cockpit compasses installed...so when he collected the aircraft, either not noted and rectified or the problem developed en route.
Flying on well past expectation of the rail sighting and not being able to return, put the poor guy into some of the worst country imaginable in the central gafa.
The huge search was done twice over the same area. Did anyone think out side the square and extend the block...alas, apparently not. And he wasn't that far from the NE corner. Vale James Knight
In those days compass (heading) clock, map, measuring stick and pencil was all there was.
Not so today. Have a look at the GPS..it says the destination is that way, xxxx miles away, and it will take you x hours and yy mins to get there.. too
easy. Until the power goes off !
Aah do love those paper maps, as one from the old school.
The compass importance just aint what it used to be, with all the alternative techo, of reliability and great accuracy in use today.
Wackett BEC recovered with some difficulty, resides in the Central Australian Air Museum, Alice Springs.
Apart from not spotting the iron rail..due visiblity or being well before expected eta for intercept time, due to the compass error, he ploughed on.
And the error was caused by; vibrating loose during the journey from Melbourne or some magnetic item interfering. The booklet states there was a reading difference in the cockpit compasses installed...so when he collected the aircraft, either not noted and rectified or the problem developed en route.
Flying on well past expectation of the rail sighting and not being able to return, put the poor guy into some of the worst country imaginable in the central gafa.
The huge search was done twice over the same area. Did anyone think out side the square and extend the block...alas, apparently not. And he wasn't that far from the NE corner. Vale James Knight
In those days compass (heading) clock, map, measuring stick and pencil was all there was.
Not so today. Have a look at the GPS..it says the destination is that way, xxxx miles away, and it will take you x hours and yy mins to get there.. too
easy. Until the power goes off !
Aah do love those paper maps, as one from the old school.
The compass importance just aint what it used to be, with all the alternative techo, of reliability and great accuracy in use today.
Wackett BEC recovered with some difficulty, resides in the Central Australian Air Museum, Alice Springs.
Imagine new aircraft instrument was invented. It only told you which way you were facing not the direction you were going. Relative to a grid system that varies over the earth, as long as you are not turning, climbing, or accelerating. The placement of other things near it rendered its readings useless and could be affected by the currents when other equipment was turned off and on. Would you pay good money to have it installed in your aircraft?
...makes me wonder why a compass is a required instrument and a GPS is not.
...makes me wonder why a compass is a required instrument and a GPS is not.
Once upon a time a seasoned old LAME looked at the compass in an aged but still absolutely serviceable aeroplane. Rubbing his chin, he pointed to the inoffensive little P9 and said . . .. "All you can say with certainty about that little number. . . . she'll tell you every time when you're pointing straight ahead."
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The ONLY thing that tells you is that the instrument has little or no hysteresis.
it is a calibrated instrument and is behaving exactly as expected.
hence it is probably still functioning within the 100ft allowance for a vfr altimeter.
...and it has no hysteresis.
It does me.
