Guitarmaster Posted October 23, 2015 Report Posted October 23, 2015 The last few flights I have felt a slight vibration. So slight that if i didn't know the airplane so well I wouldn't have noticed. Admittedly, I didn't think much of it. Well... I landed in MDW this morning and found this during the postflight. . Needless to say, I am exceedingly happy it didn't depart the airplane! 70% of the screws are missing. I think I am going to replace a few of the screws with rivets. Quote
Marauder Posted October 23, 2015 Report Posted October 23, 2015 The last few flights I have felt a slight vibration. So slight that if i didn't know the airplane so well I wouldn't have noticed. Admittedly, I didn't think much of it. Well... I landed in MDW this morning and found this during the postflight. . Needless to say, I am exceedingly happy it didn't depart the airplane! 70% of the screws are missing. I think I am going to replace a few of the screws with rivets. That is amazing to see. There are a ton of screws on those doors. How did so many of them back off? Sent from my iPad using Tapatalk Quote
Guitarmaster Posted October 23, 2015 Author Report Posted October 23, 2015 It was being held by ONE #4 screw! Clearly I will be sticking my head under the wheel well more often. Quote
Andy95W Posted October 23, 2015 Report Posted October 23, 2015 Those chintzy little #4 sheet metal screws always made me uncomfortable too. I ended up replacing mine with 6-32 SS machine screws and locknuts. A little extra weight = lots of peace of mind! 2 Quote
Yetti Posted October 23, 2015 Report Posted October 23, 2015 It looks like your screws and clips are still on the hinge.... Which would mean you have a little sheet aluminum work to do. been through any grassy fields? Quote
navysix Posted October 23, 2015 Report Posted October 23, 2015 The same thing happened to mine. All of the screws were gone. Quote
KSMooniac Posted October 23, 2015 Report Posted October 23, 2015 Wiggling the gear doors is a good preflight check, or at a minimum tapping them with a finger and listen for the acoustic response...you'll tell a difference if they're loose or not. 2 Quote
Shadrach Posted October 23, 2015 Report Posted October 23, 2015 It looks like your screws and clips are still on the hinge.... Which would mean you have a little sheet aluminum work to do. been through any grassy fields? clips? Gear doors are held by #4 sheet metal screws that are screwed directly into a stiffeners on each side of the gear well. There are no tinnerman nuts as far as I know. That area is often saturated with oil. I would clean it thoroughly and go to #6 sheet metal screws with thread sealer. A small bead of titeseal between the mating surfaces wouldn't hurt... 1 Quote
63C Posted October 23, 2015 Report Posted October 23, 2015 Getting out and seeing that would be one of those "oh sh!t" moments! 1 Quote
N201MKTurbo Posted October 23, 2015 Report Posted October 23, 2015 Good thing you caught it before it left the plane, those things are expensive! 1 Quote
Shadrach Posted October 23, 2015 Report Posted October 23, 2015 The only reason it was not lost was the linkage. You're lucky true last remaining #4 held as well. Who knows what might have happened on landing with that thing flapping around by just a rod end! 1 Quote
Guest Posted October 23, 2015 Report Posted October 23, 2015 The last few flights I have felt a slight vibration. So slight that if i didn't know the airplane so well I wouldn't have noticed. Admittedly, I didn't think much of it. Well... I landed in MDW this morning and found this during the postflight. . Needless to say, I am exceedingly happy it didn't depart the airplane! 70% of the screws are missing. I think I am going to replace a few of the screws with rivets. The gear doors are held on with #4 PK screws and Tinnerman nuts. I would bet that if you take the exhaust fairing off you will find many of the Tinnerman nuts are in the belly stuck in years of dirt and oil. They usually fall off when the doors are taken off with little regard to the Tinnerman nuts. Clarence Quote
Guitarmaster Posted October 23, 2015 Author Report Posted October 23, 2015 Thanks Clarence! There were no Tinnerman nuts to be seen. I will do some digging behind the exhaust fairing. This airplane is like an archeological dig. You never know what you will find. Hopefully I am coming to the end of the surprises shortly. 1 Quote
Shadrach Posted October 24, 2015 Report Posted October 24, 2015 The gear doors are held on with #4 PK screws and Tinnerman nuts. I would bet that if you take the exhaust fairing off you will find many of the Tinnerman nuts are in the belly stuck in years of dirt and oil. They usually fall off when the doors are taken off with little regard to the Tinnerman nuts. Clarence To my knowledge there have never been tinnerman nuts on my gear doors. Quote
Guest Posted October 24, 2015 Report Posted October 24, 2015 To my knowledge there have never been tinnerman nuts on my gear doors. Other than the newer models which have doors held on with countersunk screws which go into plate nuts, everyone I've seen have #4 Tinnerman nuts, Mooney used them everywhere. Clarence Quote
RobertGary1 Posted October 24, 2015 Report Posted October 24, 2015 (edited) A good reason not to leave the annual inspection process solely to the IA. You should be going through everything from spinner to tail nav light yourself. I bet those screws have been loose for a long time. -Robert Edited October 24, 2015 by RobertGary1 1 Quote
Guest Posted October 24, 2015 Report Posted October 24, 2015 A good reason not to leave the annual inspection process solely to the IA. You should be going through everything from spinner to tail nav light yourself. I bet those screws have been loose for a long time. -Robert Or one could argue "good reason to keep amateurs from working on aircraft", it's just as likely that the mechanic didn't touch the door. Clarence Quote
Shadrach Posted October 24, 2015 Report Posted October 24, 2015 Other than the newer models which have doors held on with countersunk screws which go into plate nuts, everyone I've seen have #4 Tinnerman nuts, Mooney used them everywhere. Clarence Well, it looks like I'll be pulling the panels and making some additions. What about the wing root trim I just pulled a few weeks ago. Would that have tinnermans nuts as well? One would have to pull the interior to put tinnermans nuts in place for every screw. Quote
Yooper Rocketman Posted October 24, 2015 Report Posted October 24, 2015 Every time I have panels off, before reinstalling them I look for the tinnermans in the holes. They like to move off the hole if they are at all loose on the aluminum. Missing (or no longer aligned) ones will usually be pretty evident when tightening the panel (or in this case, the hinge) in place. If your screws won't tighten, you need to pull the panel loose and see why. I had the rear filler panel between the fuselage and the rudder assembly fall off on my way back from Salina KS after my TKS install (back in 2001). CAV Aerospace wasn't real happy to replace it, but photos immediately after my flight home made it pretty evident they were responsible. Of course, I had to paint it, all three colors, after they sent me a primed replacement. Quote
RobertGary1 Posted October 24, 2015 Report Posted October 24, 2015 Or one could argue "good reason to keep amateurs from working on aircraft", it's just as likely that the mechanic didn't touch the door. Clarence true but I didn't say working,just inspecting. An extra set of eyes can help. -Robert Quote
Guest Posted October 24, 2015 Report Posted October 24, 2015 Well, it looks like I'll be pulling the panels and making some additions. What about the wing root trim I just pulled a few weeks ago. Would that have tinnermans nuts as well? One would have to pull the interior to put tinnermans nuts in place for every screw. Most of the fairings on vintage Mooneys were held on with #4 PK screws and Tinnerman nuts. Over the years some fall off and are replaced with larger PK screws instead of opening things up and finding and reinstalling the Tinnerman nuts. Clarence Quote
N601RX Posted October 24, 2015 Report Posted October 24, 2015 Well, it looks like I'll be pulling the panels and making some additions. What about the wing root trim I just pulled a few weeks ago. Would that have tinnermans nuts as well? One would have to pull the interior to put tinnermans nuts in place for every screw. I have a 67 F also and the wing root trim has tinnerman nuts on the inside. I've had to replace a few of them. The interior panel on each side has to be removed. 1 Quote
Shadrach Posted October 25, 2015 Report Posted October 25, 2015 (edited) I have a 67 F also and the wing root trim has tinnerman nuts on the inside. I've had to replace a few of them. The interior panel on each side has to be removed. I'm hopeful that the interior adhesive insulation has held ours in place. Thanks to both of you! Edited October 25, 2015 by Shadrach Quote
N601RX Posted October 25, 2015 Report Posted October 25, 2015 You can probably take a small magnet and tell if they are still in place. Since I've cleaned the 50 years of crud and baked on oil off my underside my nose gear ones will no longer stay in place. Quote
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