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The FAA has just issued an emergency AD that appears to ground _all_ Beech
T-34 aircraft, all models, until further notice, after confirming that the Texas Air Aces T-34 that went down a few days ago suffered a wing separation. It only allows a few hours of flight under very strict restrictions to reposition aircraft to home bases, etc. See http://www.aero-news.net for more info, I just got the email from the FAA this morning and posted the news immediately. Juan |
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On Sat, 11 Dec 2004 14:57:45 -0400, "Juan Jimenez"
wrote: The FAA has just issued an emergency AD that appears to ground _all_ Beech T-34 aircraft, all models, until further notice, after confirming that the Texas Air Aces T-34 that went down a few days ago suffered a wing separation. It only allows a few hours of flight under very strict restrictions to reposition aircraft to home bases, etc. See http://www.aero-news.net for more info, I just got the email from the FAA this morning and posted the news immediately. Juan The following was posted on a Beechcraft Email List by George Braly of GAMI. They've been working to develop a fix for the original problem. This accident is the second Texas Air Ace crash near Conroe in 13 months. Conroe crash #1 a year ago was a near perfect application of the rule of insanity - - as it was a near carbon copy of the 1999 Rydell, Georgia T-34 crash involving Sky Warriors. Conroe crash #2 - - this December, is different. 1) The main wing spar (MWS) did have an approved AMOC for the used Baron Spars, although it may have been technically illegal until sometime late last spring when the paperwork was approved. 2) In Conroe crash #1 (CC1) the MWS failed in exactly the same location for the same reasons (substantial fatigue cracking) as the 1999 crash. However, during the investigation, there was some minor fatigue cracking noted at a rivet hole on the inboard side of the aft MLG trunion attachment fitting where it attaches to the lower rear spar. There is evidence that I consider to be compelling that the first Conroe crash involved g-loading in excess of 9 g's. Yes Nine. Probably 10 or more. 3) Raytheon had a 2001 AD that provided for eddy current inspection of this rivet hole found to be a problem in CC1. That RAC AD had, apparently been complied with - - but - - apparently, missed the crack in that location on the CC2 crash this week. HOWEVER - - THE WING DID NOT FAIL THERE SO THAT ISSUE HAD NOTHING TO DO WITH THE CRASH BUT it has caused the FAA to want to look closer at that inspection procedure. From our personal experience (we have a $20,000 dollar eddy current testing machine at our shop) that small hole is difficult to inspect, as a practical manner. 4) This structure is nearly identical to all Bonanzas and Barons, and the cracks in this area may be related to landing loads, not flight loads. We don't know for certain. Again, keep in mind that a Bonanza at 3650 lbs and 4.4 g is not stressing the wing at levels that are a lot different than a T-34 at 2900 lbs and 6 g's. But, few people ever see 3 or 4 g's in their A36, either. 5) We have developed and are testing a structural repair for that specific area that is relatively simple and relatively inexpensive. I was doing flight testing last week and recording the strains in that area, and the repair appears to work well. We are planning on doing some more testing with some more strain gages, but this should resolve that for the T-34s and in the future, for all Bonanzas and Barons. It will probably be a good idea for Bonanza Baron owners to install the repair, prophylactically at some point. 6) CC2 failed, apparently, just inboard of the lower group of Huck bolts (the same ones associated with the Bonaza/Baron spar issues) on the spar carry through section. There may have been some fatigue there in one of those Huck Bolts. On first glance we should be able to eddy current inspect in the T34's with a bolt hole inspection. 7) CC2 may have failed at the left rear horizontal stabilizer. If it did, (we still do not know if it failed primary or secondary to the wing) we may never know which failed first - - the tail or the wing. The area of fatigue on the tail is, apparently, an area that has been subject to a long standing tail inspection AD. If so, the inspection of this area was inadequate. This surface on the T-34 that revealed fatigue cracks in CC2 is shared by many straight tail Bonanza type airframes. 8) None of the approved AMOC's failed to do what they were designed to do. The bolt hole inspection of the one rivet hole on the aft spar as described by RAC in the 2001 inspection AD is disappointing, but until we have further information, it is hard to draw any particular conclusions from that. Obviously, the FAA wants to take another look at that, and properly so. 9) in the past I have suggested that commercial air combat type operations should be required to carry a recording g-meter and to set standards for exceedences at a threshold well below the 6 g rating of the airplane and those standards should be part of the operating certificate for that type of activity. As one participant noted, they were frequently encountering g-induced loss of vision. Depending on the person, that normally takes well more than 4 g's. Typically around 4.5 to 5, in my experience. Thus - - it is clear that the mock combat operations are imposing a highly accelerated loading spectrum on the airframes. |
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I wonder... are the aerobatic shows that air show performers putting on with
these aircraft much less stressful on their birds than what Sky Warriors and Texas Air Aces were doing when their wings broke off? Some air show performers are going to be depressed when they find out they won't be able to do any shows for a while. "Almarz" wrote in message ... On Sat, 11 Dec 2004 14:57:45 -0400, "Juan Jimenez" wrote: The FAA has just issued an emergency AD that appears to ground _all_ Beech T-34 aircraft, all models, until further notice, after confirming that the Texas Air Aces T-34 that went down a few days ago suffered a wing separation. It only allows a few hours of flight under very strict restrictions to reposition aircraft to home bases, etc. See http://www.aero-news.net for more info, I just got the email from the FAA this morning and posted the news immediately. Juan The following was posted on a Beechcraft Email List by George Braly of GAMI. They've been working to develop a fix for the original problem. This accident is the second Texas Air Ace crash near Conroe in 13 months. Conroe crash #1 a year ago was a near perfect application of the rule of insanity - - as it was a near carbon copy of the 1999 Rydell, Georgia T-34 crash involving Sky Warriors. Conroe crash #2 - - this December, is different. 1) The main wing spar (MWS) did have an approved AMOC for the used Baron Spars, although it may have been technically illegal until sometime late last spring when the paperwork was approved. 2) In Conroe crash #1 (CC1) the MWS failed in exactly the same location for the same reasons (substantial fatigue cracking) as the 1999 crash. However, during the investigation, there was some minor fatigue cracking noted at a rivet hole on the inboard side of the aft MLG trunion attachment fitting where it attaches to the lower rear spar. There is evidence that I consider to be compelling that the first Conroe crash involved g-loading in excess of 9 g's. Yes Nine. Probably 10 or more. 3) Raytheon had a 2001 AD that provided for eddy current inspection of this rivet hole found to be a problem in CC1. That RAC AD had, apparently been complied with - - but - - apparently, missed the crack in that location on the CC2 crash this week. HOWEVER - - THE WING DID NOT FAIL THERE SO THAT ISSUE HAD NOTHING TO DO WITH THE CRASH BUT it has caused the FAA to want to look closer at that inspection procedure. From our personal experience (we have a $20,000 dollar eddy current testing machine at our shop) that small hole is difficult to inspect, as a practical manner. 4) This structure is nearly identical to all Bonanzas and Barons, and the cracks in this area may be related to landing loads, not flight loads. We don't know for certain. Again, keep in mind that a Bonanza at 3650 lbs and 4.4 g is not stressing the wing at levels that are a lot different than a T-34 at 2900 lbs and 6 g's. But, few people ever see 3 or 4 g's in their A36, either. 5) We have developed and are testing a structural repair for that specific area that is relatively simple and relatively inexpensive. I was doing flight testing last week and recording the strains in that area, and the repair appears to work well. We are planning on doing some more testing with some more strain gages, but this should resolve that for the T-34s and in the future, for all Bonanzas and Barons. It will probably be a good idea for Bonanza Baron owners to install the repair, prophylactically at some point. 6) CC2 failed, apparently, just inboard of the lower group of Huck bolts (the same ones associated with the Bonaza/Baron spar issues) on the spar carry through section. There may have been some fatigue there in one of those Huck Bolts. On first glance we should be able to eddy current inspect in the T34's with a bolt hole inspection. 7) CC2 may have failed at the left rear horizontal stabilizer. If it did, (we still do not know if it failed primary or secondary to the wing) we may never know which failed first - - the tail or the wing. The area of fatigue on the tail is, apparently, an area that has been subject to a long standing tail inspection AD. If so, the inspection of this area was inadequate. This surface on the T-34 that revealed fatigue cracks in CC2 is shared by many straight tail Bonanza type airframes. 8) None of the approved AMOC's failed to do what they were designed to do. The bolt hole inspection of the one rivet hole on the aft spar as described by RAC in the 2001 inspection AD is disappointing, but until we have further information, it is hard to draw any particular conclusions from that. Obviously, the FAA wants to take another look at that, and properly so. 9) in the past I have suggested that commercial air combat type operations should be required to carry a recording g-meter and to set standards for exceedences at a threshold well below the 6 g rating of the airplane and those standards should be part of the operating certificate for that type of activity. As one participant noted, they were frequently encountering g-induced loss of vision. Depending on the person, that normally takes well more than 4 g's. Typically around 4.5 to 5, in my experience. Thus - - it is clear that the mock combat operations are imposing a highly accelerated loading spectrum on the airframes. |
#4
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![]() "Juan Jimenez" wrote in message ... I wonder... are the aerobatic shows that air show performers putting on with these aircraft much less stressful on their birds than what Sky Warriors and Texas Air Aces were doing when their wings broke off? Some air show performers are going to be depressed when they find out they won't be able to do any shows for a while. The group in Atlanta which suffered the first wing separation flew its airplanes very frequently. I believe they had 3 aircraft. Their practice/play area was about 5 miles north of my old house, and was able to sit on my back deck and watch the mock dogfights - smoke trails and all. On VFR days, even weekdays, they flew several missions, and on the weekends, they were extremely busy. So, yes, some most?, all? of these types of operations fly those airplanes a lot, and almost every flight gets involves a meaningful amount of high G flight. I would think that the air combat folks fly much more often, and in a much harsher environment than T-34 airshow performers. I imagine airshow performers fly an hour or two a week of acro practice, a show most weekends during flying season, and whatever ferry time is required to move the airplane from place to place. Also, from what I've seen, the airshow folks using T-34's do relatively gentle aerobatics. No snaps, no 4, 5, or 6 G rolling pullouts. My guess would be that Julie Clark rarely exceeds 3.5 G's in her routine... So, to answer the question, my guess is that the air combat application may fatigue the airplane at a rate that is several times higher than the rest of the T-34 fleet. KB |
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Absolutely! There's one female operator who has over 10K hours on the
airframe and it's still going strong. These airplanes are being twisted in ways not designed. Maybe you do those things forever in an MS Simulator, but not in real life. Added to the abuse, the age and unknown previous operation conditions, and it sums up as a menu for disaster. Anyone thinking of this type of recreation should do their homework, including knowing what aircraft they'll be flying, looking through the logs of the specific airplane you'l;l fly for PROPER AD compliance, inspecting the aircraft as well as verifying the experience of their "instructor". It's very well known that many of these guys are padding the logbooks. If you think that's too much to go through, try asking the NTSB for a copy of the video of the 1st crash where the wing decapitated the pilot as it separated. You'll think again. On Sun, 12 Dec 2004 00:56:21 -0400, "Juan Jimenez" wrote: I wonder... are the aerobatic shows that air show performers putting on with these aircraft much less stressful on their birds than what Sky Warriors and Texas Air Aces were doing when their wings broke off? Some air show performers are going to be depressed when they find out they won't be able to do any shows for a while. "Almarz" wrote in message .. . On Sat, 11 Dec 2004 14:57:45 -0400, "Juan Jimenez" wrote: The FAA has just issued an emergency AD that appears to ground _all_ Beech T-34 aircraft, all models, until further notice, after confirming that the Texas Air Aces T-34 that went down a few days ago suffered a wing separation. It only allows a few hours of flight under very strict restrictions to reposition aircraft to home bases, etc. See http://www.aero-news.net for more info, I just got the email from the FAA this morning and posted the news immediately. Juan The following was posted on a Beechcraft Email List by George Braly of GAMI. They've been working to develop a fix for the original problem. This accident is the second Texas Air Ace crash near Conroe in 13 months. Conroe crash #1 a year ago was a near perfect application of the rule of insanity - - as it was a near carbon copy of the 1999 Rydell, Georgia T-34 crash involving Sky Warriors. Conroe crash #2 - - this December, is different. 1) The main wing spar (MWS) did have an approved AMOC for the used Baron Spars, although it may have been technically illegal until sometime late last spring when the paperwork was approved. 2) In Conroe crash #1 (CC1) the MWS failed in exactly the same location for the same reasons (substantial fatigue cracking) as the 1999 crash. However, during the investigation, there was some minor fatigue cracking noted at a rivet hole on the inboard side of the aft MLG trunion attachment fitting where it attaches to the lower rear spar. There is evidence that I consider to be compelling that the first Conroe crash involved g-loading in excess of 9 g's. Yes Nine. Probably 10 or more. 3) Raytheon had a 2001 AD that provided for eddy current inspection of this rivet hole found to be a problem in CC1. That RAC AD had, apparently been complied with - - but - - apparently, missed the crack in that location on the CC2 crash this week. HOWEVER - - THE WING DID NOT FAIL THERE SO THAT ISSUE HAD NOTHING TO DO WITH THE CRASH BUT it has caused the FAA to want to look closer at that inspection procedure. From our personal experience (we have a $20,000 dollar eddy current testing machine at our shop) that small hole is difficult to inspect, as a practical manner. 4) This structure is nearly identical to all Bonanzas and Barons, and the cracks in this area may be related to landing loads, not flight loads. We don't know for certain. Again, keep in mind that a Bonanza at 3650 lbs and 4.4 g is not stressing the wing at levels that are a lot different than a T-34 at 2900 lbs and 6 g's. But, few people ever see 3 or 4 g's in their A36, either. 5) We have developed and are testing a structural repair for that specific area that is relatively simple and relatively inexpensive. I was doing flight testing last week and recording the strains in that area, and the repair appears to work well. We are planning on doing some more testing with some more strain gages, but this should resolve that for the T-34s and in the future, for all Bonanzas and Barons. It will probably be a good idea for Bonanza Baron owners to install the repair, prophylactically at some point. 6) CC2 failed, apparently, just inboard of the lower group of Huck bolts (the same ones associated with the Bonaza/Baron spar issues) on the spar carry through section. There may have been some fatigue there in one of those Huck Bolts. On first glance we should be able to eddy current inspect in the T34's with a bolt hole inspection. 7) CC2 may have failed at the left rear horizontal stabilizer. If it did, (we still do not know if it failed primary or secondary to the wing) we may never know which failed first - - the tail or the wing. The area of fatigue on the tail is, apparently, an area that has been subject to a long standing tail inspection AD. If so, the inspection of this area was inadequate. This surface on the T-34 that revealed fatigue cracks in CC2 is shared by many straight tail Bonanza type airframes. 8) None of the approved AMOC's failed to do what they were designed to do. The bolt hole inspection of the one rivet hole on the aft spar as described by RAC in the 2001 inspection AD is disappointing, but until we have further information, it is hard to draw any particular conclusions from that. Obviously, the FAA wants to take another look at that, and properly so. 9) in the past I have suggested that commercial air combat type operations should be required to carry a recording g-meter and to set standards for exceedences at a threshold well below the 6 g rating of the airplane and those standards should be part of the operating certificate for that type of activity. As one participant noted, they were frequently encountering g-induced loss of vision. Depending on the person, that normally takes well more than 4 g's. Typically around 4.5 to 5, in my experience. Thus - - it is clear that the mock combat operations are imposing a highly accelerated loading spectrum on the airframes. |
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I thought that the recent TAA airplane _was_ compliant with AD 2001-13-18
R1... Juan "Almarz" wrote in message ... Absolutely! There's one female operator who has over 10K hours on the airframe and it's still going strong. These airplanes are being twisted in ways not designed. Maybe you do those things forever in an MS Simulator, but not in real life. Added to the abuse, the age and unknown previous operation conditions, and it sums up as a menu for disaster. Anyone thinking of this type of recreation should do their homework, including knowing what aircraft they'll be flying, looking through the logs of the specific airplane you'l;l fly for PROPER AD compliance, inspecting the aircraft as well as verifying the experience of their "instructor". It's very well known that many of these guys are padding the logbooks. If you think that's too much to go through, try asking the NTSB for a copy of the video of the 1st crash where the wing decapitated the pilot as it separated. You'll think again. On Sun, 12 Dec 2004 00:56:21 -0400, "Juan Jimenez" wrote: I wonder... are the aerobatic shows that air show performers putting on with these aircraft much less stressful on their birds than what Sky Warriors and Texas Air Aces were doing when their wings broke off? Some air show performers are going to be depressed when they find out they won't be able to do any shows for a while. "Almarz" wrote in message . .. On Sat, 11 Dec 2004 14:57:45 -0400, "Juan Jimenez" wrote: The FAA has just issued an emergency AD that appears to ground _all_ Beech T-34 aircraft, all models, until further notice, after confirming that the Texas Air Aces T-34 that went down a few days ago suffered a wing separation. It only allows a few hours of flight under very strict restrictions to reposition aircraft to home bases, etc. See http://www.aero-news.net for more info, I just got the email from the FAA this morning and posted the news immediately. Juan The following was posted on a Beechcraft Email List by George Braly of GAMI. They've been working to develop a fix for the original problem. This accident is the second Texas Air Ace crash near Conroe in 13 months. Conroe crash #1 a year ago was a near perfect application of the rule of insanity - - as it was a near carbon copy of the 1999 Rydell, Georgia T-34 crash involving Sky Warriors. Conroe crash #2 - - this December, is different. 1) The main wing spar (MWS) did have an approved AMOC for the used Baron Spars, although it may have been technically illegal until sometime late last spring when the paperwork was approved. 2) In Conroe crash #1 (CC1) the MWS failed in exactly the same location for the same reasons (substantial fatigue cracking) as the 1999 crash. However, during the investigation, there was some minor fatigue cracking noted at a rivet hole on the inboard side of the aft MLG trunion attachment fitting where it attaches to the lower rear spar. There is evidence that I consider to be compelling that the first Conroe crash involved g-loading in excess of 9 g's. Yes Nine. Probably 10 or more. 3) Raytheon had a 2001 AD that provided for eddy current inspection of this rivet hole found to be a problem in CC1. That RAC AD had, apparently been complied with - - but - - apparently, missed the crack in that location on the CC2 crash this week. HOWEVER - - THE WING DID NOT FAIL THERE SO THAT ISSUE HAD NOTHING TO DO WITH THE CRASH BUT it has caused the FAA to want to look closer at that inspection procedure. From our personal experience (we have a $20,000 dollar eddy current testing machine at our shop) that small hole is difficult to inspect, as a practical manner. 4) This structure is nearly identical to all Bonanzas and Barons, and the cracks in this area may be related to landing loads, not flight loads. We don't know for certain. Again, keep in mind that a Bonanza at 3650 lbs and 4.4 g is not stressing the wing at levels that are a lot different than a T-34 at 2900 lbs and 6 g's. But, few people ever see 3 or 4 g's in their A36, either. 5) We have developed and are testing a structural repair for that specific area that is relatively simple and relatively inexpensive. I was doing flight testing last week and recording the strains in that area, and the repair appears to work well. We are planning on doing some more testing with some more strain gages, but this should resolve that for the T-34s and in the future, for all Bonanzas and Barons. It will probably be a good idea for Bonanza Baron owners to install the repair, prophylactically at some point. 6) CC2 failed, apparently, just inboard of the lower group of Huck bolts (the same ones associated with the Bonaza/Baron spar issues) on the spar carry through section. There may have been some fatigue there in one of those Huck Bolts. On first glance we should be able to eddy current inspect in the T34's with a bolt hole inspection. 7) CC2 may have failed at the left rear horizontal stabilizer. If it did, (we still do not know if it failed primary or secondary to the wing) we may never know which failed first - - the tail or the wing. The area of fatigue on the tail is, apparently, an area that has been subject to a long standing tail inspection AD. If so, the inspection of this area was inadequate. This surface on the T-34 that revealed fatigue cracks in CC2 is shared by many straight tail Bonanza type airframes. 8) None of the approved AMOC's failed to do what they were designed to do. The bolt hole inspection of the one rivet hole on the aft spar as described by RAC in the 2001 inspection AD is disappointing, but until we have further information, it is hard to draw any particular conclusions from that. Obviously, the FAA wants to take another look at that, and properly so. 9) in the past I have suggested that commercial air combat type operations should be required to carry a recording g-meter and to set standards for exceedences at a threshold well below the 6 g rating of the airplane and those standards should be part of the operating certificate for that type of activity. As one participant noted, they were frequently encountering g-induced loss of vision. Depending on the person, that normally takes well more than 4 g's. Typically around 4.5 to 5, in my experience. Thus - - it is clear that the mock combat operations are imposing a highly accelerated loading spectrum on the airframes. |
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It was, but there were a few discrepancies. They did the work using a
used Baron spar, which was a legal AMOC, but from what I understand there may have been something else that was passed over as not being listed. Hey Ronco, why not call George at GAMI and ask him what he knows. May make a good story. On Sun, 12 Dec 2004 19:37:18 -0400, "Juan Jimenez" wrote: I thought that the recent TAA airplane _was_ compliant with AD 2001-13-18 R1... Juan "Almarz" wrote in message .. . Absolutely! There's one female operator who has over 10K hours on the airframe and it's still going strong. These airplanes are being twisted in ways not designed. Maybe you do those things forever in an MS Simulator, but not in real life. Added to the abuse, the age and unknown previous operation conditions, and it sums up as a menu for disaster. Anyone thinking of this type of recreation should do their homework, including knowing what aircraft they'll be flying, looking through the logs of the specific airplane you'l;l fly for PROPER AD compliance, inspecting the aircraft as well as verifying the experience of their "instructor". It's very well known that many of these guys are padding the logbooks. If you think that's too much to go through, try asking the NTSB for a copy of the video of the 1st crash where the wing decapitated the pilot as it separated. You'll think again. On Sun, 12 Dec 2004 00:56:21 -0400, "Juan Jimenez" wrote: I wonder... are the aerobatic shows that air show performers putting on with these aircraft much less stressful on their birds than what Sky Warriors and Texas Air Aces were doing when their wings broke off? Some air show performers are going to be depressed when they find out they won't be able to do any shows for a while. "Almarz" wrote in message ... On Sat, 11 Dec 2004 14:57:45 -0400, "Juan Jimenez" wrote: The FAA has just issued an emergency AD that appears to ground _all_ Beech T-34 aircraft, all models, until further notice, after confirming that the Texas Air Aces T-34 that went down a few days ago suffered a wing separation. It only allows a few hours of flight under very strict restrictions to reposition aircraft to home bases, etc. See http://www.aero-news.net for more info, I just got the email from the FAA this morning and posted the news immediately. Juan The following was posted on a Beechcraft Email List by George Braly of GAMI. They've been working to develop a fix for the original problem. This accident is the second Texas Air Ace crash near Conroe in 13 months. Conroe crash #1 a year ago was a near perfect application of the rule of insanity - - as it was a near carbon copy of the 1999 Rydell, Georgia T-34 crash involving Sky Warriors. Conroe crash #2 - - this December, is different. 1) The main wing spar (MWS) did have an approved AMOC for the used Baron Spars, although it may have been technically illegal until sometime late last spring when the paperwork was approved. 2) In Conroe crash #1 (CC1) the MWS failed in exactly the same location for the same reasons (substantial fatigue cracking) as the 1999 crash. However, during the investigation, there was some minor fatigue cracking noted at a rivet hole on the inboard side of the aft MLG trunion attachment fitting where it attaches to the lower rear spar. There is evidence that I consider to be compelling that the first Conroe crash involved g-loading in excess of 9 g's. Yes Nine. Probably 10 or more. 3) Raytheon had a 2001 AD that provided for eddy current inspection of this rivet hole found to be a problem in CC1. That RAC AD had, apparently been complied with - - but - - apparently, missed the crack in that location on the CC2 crash this week. HOWEVER - - THE WING DID NOT FAIL THERE SO THAT ISSUE HAD NOTHING TO DO WITH THE CRASH BUT it has caused the FAA to want to look closer at that inspection procedure. From our personal experience (we have a $20,000 dollar eddy current testing machine at our shop) that small hole is difficult to inspect, as a practical manner. 4) This structure is nearly identical to all Bonanzas and Barons, and the cracks in this area may be related to landing loads, not flight loads. We don't know for certain. Again, keep in mind that a Bonanza at 3650 lbs and 4.4 g is not stressing the wing at levels that are a lot different than a T-34 at 2900 lbs and 6 g's. But, few people ever see 3 or 4 g's in their A36, either. 5) We have developed and are testing a structural repair for that specific area that is relatively simple and relatively inexpensive. I was doing flight testing last week and recording the strains in that area, and the repair appears to work well. We are planning on doing some more testing with some more strain gages, but this should resolve that for the T-34s and in the future, for all Bonanzas and Barons. It will probably be a good idea for Bonanza Baron owners to install the repair, prophylactically at some point. 6) CC2 failed, apparently, just inboard of the lower group of Huck bolts (the same ones associated with the Bonaza/Baron spar issues) on the spar carry through section. There may have been some fatigue there in one of those Huck Bolts. On first glance we should be able to eddy current inspect in the T34's with a bolt hole inspection. 7) CC2 may have failed at the left rear horizontal stabilizer. If it did, (we still do not know if it failed primary or secondary to the wing) we may never know which failed first - - the tail or the wing. The area of fatigue on the tail is, apparently, an area that has been subject to a long standing tail inspection AD. If so, the inspection of this area was inadequate. This surface on the T-34 that revealed fatigue cracks in CC2 is shared by many straight tail Bonanza type airframes. 8) None of the approved AMOC's failed to do what they were designed to do. The bolt hole inspection of the one rivet hole on the aft spar as described by RAC in the 2001 inspection AD is disappointing, but until we have further information, it is hard to draw any particular conclusions from that. Obviously, the FAA wants to take another look at that, and properly so. 9) in the past I have suggested that commercial air combat type operations should be required to carry a recording g-meter and to set standards for exceedences at a threshold well below the 6 g rating of the airplane and those standards should be part of the operating certificate for that type of activity. As one participant noted, they were frequently encountering g-induced loss of vision. Depending on the person, that normally takes well more than 4 g's. Typically around 4.5 to 5, in my experience. Thus - - it is clear that the mock combat operations are imposing a highly accelerated loading spectrum on the airframes. |
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We have someone working on that.
![]() "Almarz" wrote in message news ![]() It was, but there were a few discrepancies. They did the work using a used Baron spar, which was a legal AMOC, but from what I understand there may have been something else that was passed over as not being listed. Hey Ronco, why not call George at GAMI and ask him what he knows. May make a good story. On Sun, 12 Dec 2004 19:37:18 -0400, "Juan Jimenez" wrote: I thought that the recent TAA airplane _was_ compliant with AD 2001-13-18 R1... Juan "Almarz" wrote in message . .. Absolutely! There's one female operator who has over 10K hours on the airframe and it's still going strong. These airplanes are being twisted in ways not designed. Maybe you do those things forever in an MS Simulator, but not in real life. Added to the abuse, the age and unknown previous operation conditions, and it sums up as a menu for disaster. Anyone thinking of this type of recreation should do their homework, including knowing what aircraft they'll be flying, looking through the logs of the specific airplane you'l;l fly for PROPER AD compliance, inspecting the aircraft as well as verifying the experience of their "instructor". It's very well known that many of these guys are padding the logbooks. If you think that's too much to go through, try asking the NTSB for a copy of the video of the 1st crash where the wing decapitated the pilot as it separated. You'll think again. On Sun, 12 Dec 2004 00:56:21 -0400, "Juan Jimenez" wrote: I wonder... are the aerobatic shows that air show performers putting on with these aircraft much less stressful on their birds than what Sky Warriors and Texas Air Aces were doing when their wings broke off? Some air show performers are going to be depressed when they find out they won't be able to do any shows for a while. "Almarz" wrote in message m... On Sat, 11 Dec 2004 14:57:45 -0400, "Juan Jimenez" wrote: The FAA has just issued an emergency AD that appears to ground _all_ Beech T-34 aircraft, all models, until further notice, after confirming that the Texas Air Aces T-34 that went down a few days ago suffered a wing separation. It only allows a few hours of flight under very strict restrictions to reposition aircraft to home bases, etc. See http://www.aero-news.net for more info, I just got the email from the FAA this morning and posted the news immediately. Juan The following was posted on a Beechcraft Email List by George Braly of GAMI. They've been working to develop a fix for the original problem. This accident is the second Texas Air Ace crash near Conroe in 13 months. Conroe crash #1 a year ago was a near perfect application of the rule of insanity - - as it was a near carbon copy of the 1999 Rydell, Georgia T-34 crash involving Sky Warriors. Conroe crash #2 - - this December, is different. 1) The main wing spar (MWS) did have an approved AMOC for the used Baron Spars, although it may have been technically illegal until sometime late last spring when the paperwork was approved. 2) In Conroe crash #1 (CC1) the MWS failed in exactly the same location for the same reasons (substantial fatigue cracking) as the 1999 crash. However, during the investigation, there was some minor fatigue cracking noted at a rivet hole on the inboard side of the aft MLG trunion attachment fitting where it attaches to the lower rear spar. There is evidence that I consider to be compelling that the first Conroe crash involved g-loading in excess of 9 g's. Yes Nine. Probably 10 or more. 3) Raytheon had a 2001 AD that provided for eddy current inspection of this rivet hole found to be a problem in CC1. That RAC AD had, apparently been complied with - - but - - apparently, missed the crack in that location on the CC2 crash this week. HOWEVER - - THE WING DID NOT FAIL THERE SO THAT ISSUE HAD NOTHING TO DO WITH THE CRASH BUT it has caused the FAA to want to look closer at that inspection procedure. From our personal experience (we have a $20,000 dollar eddy current testing machine at our shop) that small hole is difficult to inspect, as a practical manner. 4) This structure is nearly identical to all Bonanzas and Barons, and the cracks in this area may be related to landing loads, not flight loads. We don't know for certain. Again, keep in mind that a Bonanza at 3650 lbs and 4.4 g is not stressing the wing at levels that are a lot different than a T-34 at 2900 lbs and 6 g's. But, few people ever see 3 or 4 g's in their A36, either. 5) We have developed and are testing a structural repair for that specific area that is relatively simple and relatively inexpensive. I was doing flight testing last week and recording the strains in that area, and the repair appears to work well. We are planning on doing some more testing with some more strain gages, but this should resolve that for the T-34s and in the future, for all Bonanzas and Barons. It will probably be a good idea for Bonanza Baron owners to install the repair, prophylactically at some point. 6) CC2 failed, apparently, just inboard of the lower group of Huck bolts (the same ones associated with the Bonaza/Baron spar issues) on the spar carry through section. There may have been some fatigue there in one of those Huck Bolts. On first glance we should be able to eddy current inspect in the T34's with a bolt hole inspection. 7) CC2 may have failed at the left rear horizontal stabilizer. If it did, (we still do not know if it failed primary or secondary to the wing) we may never know which failed first - - the tail or the wing. The area of fatigue on the tail is, apparently, an area that has been subject to a long standing tail inspection AD. If so, the inspection of this area was inadequate. This surface on the T-34 that revealed fatigue cracks in CC2 is shared by many straight tail Bonanza type airframes. 8) None of the approved AMOC's failed to do what they were designed to do. The bolt hole inspection of the one rivet hole on the aft spar as described by RAC in the 2001 inspection AD is disappointing, but until we have further information, it is hard to draw any particular conclusions from that. Obviously, the FAA wants to take another look at that, and properly so. 9) in the past I have suggested that commercial air combat type operations should be required to carry a recording g-meter and to set standards for exceedences at a threshold well below the 6 g rating of the airplane and those standards should be part of the operating certificate for that type of activity. As one participant noted, they were frequently encountering g-induced loss of vision. Depending on the person, that normally takes well more than 4 g's. Typically around 4.5 to 5, in my experience. Thus - - it is clear that the mock combat operations are imposing a highly accelerated loading spectrum on the airframes. |
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