I have just had an article published in "The Moth". "The Moth" is the magazine of the de Havilland Moth Club. Not the most fun article, but important. A year and half later I still furious that people I trusted knew better and went ahead and did what they did. Although the article involves a certified aircraft the philosophy applies to homebuilts. Research to the best of your ability and document it. That "improvement" could be fatal.
We have an ethical responsibility for how we maintain our aircraft. It has been said many times before, but it bears repeating. We are only the caretakers of these aircraft for future generations. We owe it to future operators to maintain the aircraft to the highest possible standards.
Aircraft get modified all the time for all kinds of reasons. This is why things get improved and a flying Tiger Moth is not the same one that rolled out of the factory. Flaws are identified; materials become obsolete and need to be upgraded to a modern equivalent. The sometimes irritating trail of paperwork is actually there for a purpose. To let those that follow, know what the current modification state of the aircraft is, and why things are as they are. There are procedures to follow if you want to modify an aircraft. In the case of the Tiger Moth, in most parts of the world, there are two basic methods; a Supplemental Type Certificate, or with permission from the holder of the Type Certificate. They both involve an engineering analysis of the proposed modification. In all cases the modifications need to be documented in the technical logs. The following unfortunately happened, causing ruined reputations and thousands of dollars in damage to a perfectly innocent aircraft.
I had been associated with a group that has been operating a Tiger Moth for a very long time. One of the members decided that manoeuvring the aircraft out of the hanger was beyond his ability without assistance despite the fact that no one else had had an issue in over 25 years of operations. His solution was to weld some lugs on to the undercarriage so a tow bar could be hooked up. Since he was not a welder, he got a maintenance engineer who was a welder to perform the work without consulting the engineer who had been maintaining the aircraft for years. For the sake of brevity, I will omit their qualifications, but rest assured both of these individuals were absolutely aware they could not perform this work legally. What then followed made me feel like I was dealing with children fighting in a sandbox.
It was pointed out to them by someone with decades of experience in the quite large aircraft manufacturing business that they could not just weld where they felt like it. They ignored him. It was then brought to my attention. The work was not in the logbook. A quick call to another welder confirmed my earlier points. An e-mail to DH Support with photographs of the work elicited a quick response with a recommendation that the aircraft not be flown as the legs were compromised.
This is where things descended into farce. I passed on the email from DH Support. What I got in return was a tirade against my interference in their work and a paraded list of qualifications of the welder-none of which were relevant. In the case of the Tiger Moth, the leg is not just a bent tube; it is made from high strength T50 thin-walled tubing that once heated by any form of welding, will have its strength reduced considerably. In other words the hockey sticks on the gear were now only useful as, well, hockey sticks. This refusal to accept the advice of DH Support finished with a commitment to remove the tabs because the purists had objected to the modification. The legs would then be re-certified for strength. Back to DH Support who proceeded to politely cut the response to ribbons by pointing out that re-certifying the leg was beyond the abilities of someone without access to the full engineering specs for the leg which are not publicly available, a fully equipped laboratory and the regulatory approval to do so. The usual engineer then paid a visit, restrained himself admirably upon seeing what had been done to the aircraft which was supposed to be under his care exclusively and stated the obvious-he would not be able to sign the aircraft off on its next annual inspection without the legs being replaced.
They kept flying it.
At this point I lost my sense of humour and made a call to the authorities-in this case Transport Canada. Upon their arrival they noted three violations: 1) no logbook entry 2) performing maintenance they were not approved to do, and 3) flying the aircraft without the maintenance being signed off. This is where we get to the sandbox aspect. When asked who performed the welding, the welder and the person who directed it responded they didnt know. The authorities let that slide and used their discretion, offering two options. The owners could ground the aircraft themselves and replace the legs or Transport Canada would ground the aircraft and the paperwork would get much more involved and serious. You might, as I have, find yourself thinking the following, An aircraft in a locked hanger had welding performed on it with no entries in the logs by persons unknown and you hopped in and went flying? Then someone cut the tabs off and you went flying again? I am at a loss for words. For the record, Transport Canada is in possession of an email identifying the welder.
Aviation is based on trust. An engineer performing work outside of his licence privileges can bring down an aircraft just as well as a pilot performing dangerous stunts. When somebody sends out the door an aircraft with a major structural component that will no longer meet its rated load, he is effectively saying that the life of anybody flying in the aircraft is unimportant. I didnt want to be responsible for an accident occurring years from now (or next week) because I chose the easy path and stood by and did nothing. Regulations do serve a purpose. They are usually paid for in blood. Primary structure of an aircraft is sometimes more complicated than it appears. I didnt know the properties of the steel in a Tiger Moth leg, but I did know to not weld on it without guidance. Mistakes happen. Willful disregard is reprehensible. When it comes to safety, you need to park your ego at the door and not act like a child caught stealing cookies. As my lawyer friend is fond of saying. Govern yourself accordingly.
Robin Tripp
Would you know this leg was scrap?
We have an ethical responsibility for how we maintain our aircraft. It has been said many times before, but it bears repeating. We are only the caretakers of these aircraft for future generations. We owe it to future operators to maintain the aircraft to the highest possible standards.
Aircraft get modified all the time for all kinds of reasons. This is why things get improved and a flying Tiger Moth is not the same one that rolled out of the factory. Flaws are identified; materials become obsolete and need to be upgraded to a modern equivalent. The sometimes irritating trail of paperwork is actually there for a purpose. To let those that follow, know what the current modification state of the aircraft is, and why things are as they are. There are procedures to follow if you want to modify an aircraft. In the case of the Tiger Moth, in most parts of the world, there are two basic methods; a Supplemental Type Certificate, or with permission from the holder of the Type Certificate. They both involve an engineering analysis of the proposed modification. In all cases the modifications need to be documented in the technical logs. The following unfortunately happened, causing ruined reputations and thousands of dollars in damage to a perfectly innocent aircraft.
I had been associated with a group that has been operating a Tiger Moth for a very long time. One of the members decided that manoeuvring the aircraft out of the hanger was beyond his ability without assistance despite the fact that no one else had had an issue in over 25 years of operations. His solution was to weld some lugs on to the undercarriage so a tow bar could be hooked up. Since he was not a welder, he got a maintenance engineer who was a welder to perform the work without consulting the engineer who had been maintaining the aircraft for years. For the sake of brevity, I will omit their qualifications, but rest assured both of these individuals were absolutely aware they could not perform this work legally. What then followed made me feel like I was dealing with children fighting in a sandbox.
It was pointed out to them by someone with decades of experience in the quite large aircraft manufacturing business that they could not just weld where they felt like it. They ignored him. It was then brought to my attention. The work was not in the logbook. A quick call to another welder confirmed my earlier points. An e-mail to DH Support with photographs of the work elicited a quick response with a recommendation that the aircraft not be flown as the legs were compromised.
This is where things descended into farce. I passed on the email from DH Support. What I got in return was a tirade against my interference in their work and a paraded list of qualifications of the welder-none of which were relevant. In the case of the Tiger Moth, the leg is not just a bent tube; it is made from high strength T50 thin-walled tubing that once heated by any form of welding, will have its strength reduced considerably. In other words the hockey sticks on the gear were now only useful as, well, hockey sticks. This refusal to accept the advice of DH Support finished with a commitment to remove the tabs because the purists had objected to the modification. The legs would then be re-certified for strength. Back to DH Support who proceeded to politely cut the response to ribbons by pointing out that re-certifying the leg was beyond the abilities of someone without access to the full engineering specs for the leg which are not publicly available, a fully equipped laboratory and the regulatory approval to do so. The usual engineer then paid a visit, restrained himself admirably upon seeing what had been done to the aircraft which was supposed to be under his care exclusively and stated the obvious-he would not be able to sign the aircraft off on its next annual inspection without the legs being replaced.
They kept flying it.
At this point I lost my sense of humour and made a call to the authorities-in this case Transport Canada. Upon their arrival they noted three violations: 1) no logbook entry 2) performing maintenance they were not approved to do, and 3) flying the aircraft without the maintenance being signed off. This is where we get to the sandbox aspect. When asked who performed the welding, the welder and the person who directed it responded they didnt know. The authorities let that slide and used their discretion, offering two options. The owners could ground the aircraft themselves and replace the legs or Transport Canada would ground the aircraft and the paperwork would get much more involved and serious. You might, as I have, find yourself thinking the following, An aircraft in a locked hanger had welding performed on it with no entries in the logs by persons unknown and you hopped in and went flying? Then someone cut the tabs off and you went flying again? I am at a loss for words. For the record, Transport Canada is in possession of an email identifying the welder.
Aviation is based on trust. An engineer performing work outside of his licence privileges can bring down an aircraft just as well as a pilot performing dangerous stunts. When somebody sends out the door an aircraft with a major structural component that will no longer meet its rated load, he is effectively saying that the life of anybody flying in the aircraft is unimportant. I didnt want to be responsible for an accident occurring years from now (or next week) because I chose the easy path and stood by and did nothing. Regulations do serve a purpose. They are usually paid for in blood. Primary structure of an aircraft is sometimes more complicated than it appears. I didnt know the properties of the steel in a Tiger Moth leg, but I did know to not weld on it without guidance. Mistakes happen. Willful disregard is reprehensible. When it comes to safety, you need to park your ego at the door and not act like a child caught stealing cookies. As my lawyer friend is fond of saying. Govern yourself accordingly.
Robin Tripp
Would you know this leg was scrap?
