Gearophobia
- Thread starter guzziduck
- Start date
I have been thinking of writing this for a while. If I understood the posts about JBs gear failure, it was the rear spar bracket that the retract strut goes to. On Cruisairs there is an AD to remove paint on the bracket and inspect at each annual. There have been many brackets found with cracks, and since I have parted out a number of Cruisairs I have seen almost half of the brackets that I removed with cracks in them. The scary part is that some of them had cracks that were only visible when the bracket was removed. I dont believe that the Cruismasters have that same AD because the bracket on them is designed better. There is not as much twisting force on the shorter 14-19 bracket. My Cruisair has the hand pump hydraulic landing gear STC, which uses the retract parts, including the rear spar bracket from the 14-19. A few monthes ago a friend looking at my plane said that he thought he saw a crack in one of my brackets. I could not find it when I looked so I assumed he had seen a crack in the paint. After reading about JBs gear failure, I went back and looked again and sure enough there was a small crack at one of the welds. 8 or 10 years ago, at a Columbia Fly In I looked under a 14-19 and noticed a badly broken rear spar bracket. I located the owner and told him about it and he elected to fly the plane home with the gear down. I was told that the plane was later lost in an unrelated accident._____The point of my rambling is that I think the 14-19s-/2 should have the same AD that the 14-13s have. An extra hour on an annual might have saved JBs plane and all of the heart ache that it has caused him. We all hate more rules,but we hate the sound of a prop hitting the runway even more._____Grant.
mhackens
New member
Wow, you guys are scaring me :!: :!: My bird is setting on a new?? rebuilt gear that I assumed would be trouble free. Lynn talks about the gear being the weak part of the airplane and now this. :shock:
My gear was broken off the aircraft from a ground loop. (side load) I stripped the rear fitting and inspected it on the aircraft. Now it is painted. I am considering, do to the history here, stripping it again before flight so I can better inspect it.
I have the fuselage more or less, done and have started cleaning up the engine, mount, and ext. for install. Found enough metal in the screen to warrant an inspection of the lifters.
Not a good day, they are bad.
I need a drill jig to remove several broken exhaust studs, right after I twisted them off I found one advertised that bolted right on the four studs. Now that I need it I can't find were I saw it. Anyone have any ideas :?:
My gear was broken off the aircraft from a ground loop. (side load) I stripped the rear fitting and inspected it on the aircraft. Now it is painted. I am considering, do to the history here, stripping it again before flight so I can better inspect it.
I have the fuselage more or less, done and have started cleaning up the engine, mount, and ext. for install. Found enough metal in the screen to warrant an inspection of the lifters.
Not a good day, they are bad.
I need a drill jig to remove several broken exhaust studs, right after I twisted them off I found one advertised that bolted right on the four studs. Now that I need it I can't find were I saw it. Anyone have any ideas :?:
Jonathan Baron
New member
Always making soft landings is a nice goal but it's not a solution...after all, who says to himself on final, "Hmmm....I think I'm going to make this one a hard landing...maybe add a bounce or two."
I'm attaching a photo of what broke. You'll note no twisting of metal...it simply broke and the landing was anything but hard. This is the bracket between the two blocks that hold the gear over-center, and the blocks butt against each other each time the gear are lowered. This design was changed later in the production run to something more suitable for the heavier Cruisemaster.
Metal, unlike wood, is made of crystals, pressed together. These crystals grind against each other over time. They call it metal fatigue but it's actually a bunch of crystals working their way apart until their little community can't be held together any longer. Bob Seals said there had been a crack where you can't easily spot it: behind the microswitch that let's you know that the gear is fully down. The solution would seem to be to remove the switch every annual and have a look...maybe that would work. I don't know. I also don't know if simply switching out this style of gear for the later one would be a better solution. Perhaps.
The NTSB is still pondering this accident. The folks handling this for them live in Hawaii, thus they can't simply go to the wreck and examine it firsthand as I suggested when I got tired of their phone calls and request for more and more photos. In the end you have a limited production airplane with an even more limited production landing gear drag strut. You have a gear failure unlike those other ones reported. This no doubt is what's troubling their minds.
In the end there's no all-purpose solution or approach to operating complex aircraft older than most of their owners. There will be a weak link somethere. Fortunatly most don't produce similar results.
JonathanView attachment 1
I'm attaching a photo of what broke. You'll note no twisting of metal...it simply broke and the landing was anything but hard. This is the bracket between the two blocks that hold the gear over-center, and the blocks butt against each other each time the gear are lowered. This design was changed later in the production run to something more suitable for the heavier Cruisemaster.
Metal, unlike wood, is made of crystals, pressed together. These crystals grind against each other over time. They call it metal fatigue but it's actually a bunch of crystals working their way apart until their little community can't be held together any longer. Bob Seals said there had been a crack where you can't easily spot it: behind the microswitch that let's you know that the gear is fully down. The solution would seem to be to remove the switch every annual and have a look...maybe that would work. I don't know. I also don't know if simply switching out this style of gear for the later one would be a better solution. Perhaps.
The NTSB is still pondering this accident. The folks handling this for them live in Hawaii, thus they can't simply go to the wreck and examine it firsthand as I suggested when I got tired of their phone calls and request for more and more photos. In the end you have a limited production airplane with an even more limited production landing gear drag strut. You have a gear failure unlike those other ones reported. This no doubt is what's troubling their minds.
In the end there's no all-purpose solution or approach to operating complex aircraft older than most of their owners. There will be a weak link somethere. Fortunatly most don't produce similar results.
JonathanView attachment 1
Larry Lowenkron
New member
So is the attached jpg the answer? The insurance adjuster for me when I had my lg event suggested so.
Jonathan Baron
New member
Larry, I must say I have wondered if a cleaned up version of the gear, set up as fixed, with the opening in the wing closed, and contemporary wheel faring applied might actually make for as fast or even a faster airplane.
Oh, and I'm not sure if I mentioned this but my favorite shop in your home state that I may have told you about <cough> notes in the logs that they detected damage in the left landing gear and overhauled it. Ah...how often I've fantasized about overhauling the owner of that particular establishment :twisted:
Jonathan
Oh, and I'm not sure if I mentioned this but my favorite shop in your home state that I may have told you about <cough> notes in the logs that they detected damage in the left landing gear and overhauled it. Ah...how often I've fantasized about overhauling the owner of that particular establishment :twisted:
Jonathan
lwford
New member
Monti, the gear is the weak link of the Cruisemaster, watch it like a hawk. Your stud tool is available from ATS 800-248-0638 and Gibson Aviation 800-992-4880. The -2 gear is a better design but still far from bullet proof. I get under the crate and eye that drag link like Dolly Partons jugs.I will be at OSH 1st part of the week and splitting for home Wed. Lord willin and the creek don' t rise. Lynn the crate
I see now that I was confused on what had let go on JBs plane. I cant get my computer to show me the photos, but I believe JBs must be a very early 14-19 , that had retract struts that hinge like a 14-13, with the pivot point being below the centerline of the strut. That design was flawed enough in the 14-13s that Bellanca issued Service Bulletin #24 on August 13 ,1948, to put down stops on the retract screws so that the butt plates that come together in the down position dont press too hard against each other and cause the kind of failure that JB had. I dont know what type of stops or limits the early 14-19s had on the hydraulic acuators , but if they are not adjusted right it could cause the fatigue ,and then failure. I can only assume that the engine driven hydraulics of a 14 -19 would put even more strain on the parts than the hand crank of a 14-13.______Grant.
Jonathan Baron
New member
I am told that the strut design on 14-19s was changed during its production run, though I'm not sure and it doesn't matter in my case. Mine was among the first ten built, I believe.
When you look at this two-blocks-butting setup, with the two blocks having to pretty much collide each time the gear is lowered, you may wonder why it took so long for it to let go. Easy to note after the fact, eh? I did not anticipate such a failure because I could only note its perils after it failed and there were sooooo many things that needed attending to that were of absolute priority such as the engine, the prop, the mods to make it flyable by me, and then getting the gear/hydraulic system to work at all.
One important cludge by Bellanca was the silly work-around involving the spinner and back plate, the latter of which was made of very thin aluminum and attached on top of the prop hub with many screws that made the plate press against large, raised letters (Hartzell Hydro Selective, as I recall, in all caps). This caused cracks, of course, and the back plate nearly came apart. Then another system would fail, and so forth. Hard to look around for stuff that hasn't broken yet under such circumstances unless you take the aircraft out of service for two years or so and restore it thoroughly.
Its final flight under my stewardship was its finest one. Everything worked wonderfully without a hint of a problem for over 26 hours in a row...until it didn't :roll:
This was the longest period it operated, without fail, during the eight years I owned it. Forgive me if my reaction when it came to rest for the last time was far from sadness or tears.
Jonathan
When you look at this two-blocks-butting setup, with the two blocks having to pretty much collide each time the gear is lowered, you may wonder why it took so long for it to let go. Easy to note after the fact, eh? I did not anticipate such a failure because I could only note its perils after it failed and there were sooooo many things that needed attending to that were of absolute priority such as the engine, the prop, the mods to make it flyable by me, and then getting the gear/hydraulic system to work at all.
One important cludge by Bellanca was the silly work-around involving the spinner and back plate, the latter of which was made of very thin aluminum and attached on top of the prop hub with many screws that made the plate press against large, raised letters (Hartzell Hydro Selective, as I recall, in all caps). This caused cracks, of course, and the back plate nearly came apart. Then another system would fail, and so forth. Hard to look around for stuff that hasn't broken yet under such circumstances unless you take the aircraft out of service for two years or so and restore it thoroughly.
Its final flight under my stewardship was its finest one. Everything worked wonderfully without a hint of a problem for over 26 hours in a row...until it didn't :roll:
This was the longest period it operated, without fail, during the eight years I owned it. Forgive me if my reaction when it came to rest for the last time was far from sadness or tears.
Jonathan
Alain1
New member
Well,well,well, after reading all this, I went and had a second look at my gears. Did it 6 weeks ago when I did the annual but I really adjusted and cleaned my glasses and stuck my nose in there. Guess what! After cleaning properly, L/H Aft spar gear fitting cracked on both side near the 2 bottom bolts. :evil: And refering to Richard's posting about the stop at the end of the screw, No crack on the R/H side where the stop is installed. :shock:
When gear down on R/H side, the stops are touching at the drag link hinge position near the gear down indicator switch and the stop on screw just at the right place too, no twisting jerk effect when I kick the wheel backward , (simulating same kind of shock as when it touch down).
On the R/H side, when I kick the wheel backward, since the stops have a little clearance in between, Like if the gear were not completely cranked down, The aft drag link move a bit downward near the hinge and I can ear a little squeeking sound like when a weld is broken.
I will fix or get a fitting, and install a similar stop on the screw like on the R/H side. Of course once back together I will adjust the R/H drag struts so all stops meet when gear down. :roll:
By the way, I am looking for a spare fitting if anybody has one.
Alain
When gear down on R/H side, the stops are touching at the drag link hinge position near the gear down indicator switch and the stop on screw just at the right place too, no twisting jerk effect when I kick the wheel backward , (simulating same kind of shock as when it touch down).
On the R/H side, when I kick the wheel backward, since the stops have a little clearance in between, Like if the gear were not completely cranked down, The aft drag link move a bit downward near the hinge and I can ear a little squeeking sound like when a weld is broken.
I will fix or get a fitting, and install a similar stop on the screw like on the R/H side. Of course once back together I will adjust the R/H drag struts so all stops meet when gear down. :roll:
By the way, I am looking for a spare fitting if anybody has one.
Alain
Alain, check out Service Bulletin #18, concerning the rear spar bracket. There was a reinforcement added to the bracket. It has not always been done to every plane. Also , the squeak you hear may be the bracket moving on the rear spar.I helped a friend change one of these brackets because of a crack and we discovered that it was loose on the spar and the bolt holes had elongated. We drilled the bracket and the spar for the next size bolt,and varnished the heck out of the spar (including the bolt holes) and snugged it all back together. All was well. As for the adjustment of the landing gear down stops, you might want to be careful of having them close too tightly. Service bulletin #24 is the one that called for the stops , and it is to prevent preloading of the drag strut. I was told by a highly experienced I.A. that there is supposed to be some set amount of clearance when the gear is at rest. I dont remember what amount he said,and I have never seen it in print,but maybe Dan C. or Larry L. know more about this issue .____Alain, call me with your mailing address and i will send you the missing down stop. I understand that you had to have the tach that I sent you overhauled. I owe you one because I thought it was good. 707-928-5538 ______Grant.
Dan Cullman
New member
The cracks in the face of the triangular flanges where the attach bolts are..........were caused by overtorque of those bolts. The cracks in the lower part of that "U" shaped fitting are what can cause the failure of the landing gear. Alain, by serial number of your airplane, you should have the updated rear spar fitting. Dan
Dan Cullman
New member
BTW........all these cracks are repairable by welding. Dan
Jonathan Baron
New member
Yes, the 709 ride...I forget what they call it but it's the aviation definition of adding insult to injury, Mike. When the Fed who was handling my situation at Columbia suggested one I lit him up. Lit him up several times because the poor guy had a dreadful problem: his lips kept moving. Had he attended to that we would have had no trouble at all.
I don't mean to suggest they're all the same. A great friend of mine is one. He said those rides have become much more commonplace. Then the NTSB, examining the same evidence, came to a very different conclusion and the subject has not come up since. If it does I'll just toss a Fed in my Luscombe, take off and land a couple of times and be done with it. It won't change the fact that the gear would have broke regardless, and at least I made a fool squirm. The former saddens me but the latter fills me with joy :lol:
Jonathan
I don't mean to suggest they're all the same. A great friend of mine is one. He said those rides have become much more commonplace. Then the NTSB, examining the same evidence, came to a very different conclusion and the subject has not come up since. If it does I'll just toss a Fed in my Luscombe, take off and land a couple of times and be done with it. It won't change the fact that the gear would have broke regardless, and at least I made a fool squirm. The former saddens me but the latter fills me with joy :lol:
Jonathan