Check Gear

lwford

lwford

New member
Boys I've said for years to keep an eye on the gear of your plane. I had another failure this morning on gear UP. When the gear came up all was fine until I hit a bit of turbulence and noticed that the right red gear up light blinked. I slowed lowered the gear all fine two green and then retracted it. This time the right gear red light did not light although the gear was up with the mechanical (MIG) indicators. I had this before with the left gear in May 2004. I returned to base and after landing discovered that the right gear bracket was cracked and broke. The bracket is p/n 18941-10 and holds the retract cylinder to the rear spar. Now the good and bad news. This happened to the right gear in March 1994 and was logged before I owned the crate. The good news for me is that in getting a new bracket from AAC I had one made twice the thickness in 2004, so that was installed and flew again today all fine. The bad news was that I called Carroll at AAC and there are no brackets to be had. I'm going to try and have another made twice the thickness so I will have another spare. I had 800 hours on that bracket and hundreds of landings. They break when they sit, they break when you fly---your choice. Lynn the crate
 
Is there a possibility of having a small run made? If this is a common problem, I would be interested in a set of thicker brackets for my ship.
-Adam
 
I'm meeting with a machinist friend next week. He made that part for me years ago and doesn't remember the job. I kept the two broken fittings so he can make a new one from the old. In all cases the fitting broke in the middle hidden by the hyd. cyl mounting. It doesn't take long after that for it to bend and now all the load is on the bolts that go thru the rear spar. The heads on these bend and if your gear switches are set right you know there is a problem the gear lights blink and go out. Again I advise all the Cruisemaster owners to give that fitting a real good look. I can't be the only one with this problem although the crate fly's a good bit with hundreds of landings. Lynn the crate
 
The ATC gear STC for hydraulic gear in a Cruisair has the technical drawings for that part. My copy burned up but I think Larry L. has the drawings or maybe I had sent copies to the club. Using a thicker metal is a very good idea. _____Grant.
 
This would be a WONDERFUL thing to distrubute/share with the group or crowdfund a parts run. I have also had the same issue.
 
Thanks for the heads-up Lynn... where did the bracket fail? Is there a weak spot because of a flaw in design? The thicker material will probably resolve the problem for the remainder of our lifetime (well, maybe not Adam's) but we might want to spend the extra money and effort to have the parts shot-peened as a final process. Tell your machinist that we are going into volume production! I would like two sets... Rob
 
Other than bad landings, I think the main cause of the bracket failure is an over pressure relief valve that is set too high. In the down position extra pressure just goes against the limit of the cylinder, but in the up position, too much pressure pulls the cylinder away from the rear spar and puts all of the strain on that little bracket. I dont know if the Bellanca power-pack is adjustable or not, but I have heard the number 850 PSI is what they are set/built at and I think that is much more than is needed to keep your gear up. Making the brackets stronger is a very good idea. ____Grant.
 
The bracket fails in the middle between the two tangs. It then bends enough to break one of the tangs and bend the bolt head by this time you know of the problem because your red up light has gone out. Grant is on the right track, the pump is set to 850 and the retract cylinder is under constant up pressure . I will check with my machinist friend as to what the costs would be to make a few of these. Making the bracket out of 1/8 stock fixes the issue. This is small potatoes on the Spartans it is the gear trunions and that my friend is $35000 dollars for two custom made. Sadly this should be a priority of AAC but I guess like all Bellanca's it's history. Lynn
 
Lynn,
Count me in for a set if they don't cost more than my airplane Haha!
Love Spartans but obviously can't afford one
 
Lynn,
I would be interested in a set, as well. I've got a 14-19, but it has the updated strut set up. Tom Robinson
 
Since the original brackets are rather thin metal, going to thicker metal is great, but remember that most Masters dont have the adjustable ends on the retract cylinders, so making the bracket thicker will change the geometry of your retract struts. Not by a lot, but you want the struts to be proper when in the down position. You will probably need to take that into consideration and drill the holes for the clevis pin THE SAME DISTANCE FROM THE SPAR as an original one was. That will be much easier than the expensive, time consuming machine work of adjusting a cylinder. Vikings went to an adjustable end on the cylinder ram, but they are not a direct replacement for the Master. Master cylinders can be modified to use the adjustable Viking rod by using the Master internal plungers/stoppers (cant think of the proper name) on the Viking rod. The outer cases are the same. ___Just another 2 cents worth. ___Grant.
 
Grant, I took that into consideration when I had the beefed up ones made. All specs are the same and only thing really different is the thicker material. Will be interesting to note what a set will set me back this time. There is lots of welding on the original so maybe these can be machined I don't know yet. We will see what my friend says next week. I had purchased the rear gear brackets 18939-20 from AAC years ago but have never needed them, that's a plus! Lynn the crate
 
We found a crack in my right cylinder bracket yesterday, so I am grounded until I get a new bracket. :cry: Lynn, did you get brackets made? Does anyone have a drawing?
Ralph
 
I took the brackets to my machinist friend and told him no rush. I am waiting for his response so this could take some time. He was talking about machining a solid bracket instead of the welded originals and would make a prototype. You could have your bracket TIG welded. I don't think my solution is going to be cheap and easy. AAC should be doing what I'm trying to do, as stated I will keep the Forum informed. Lynn
 
Larry L. Did I send you the drawings with the bracket information? I have several brackets that are bent all to hell, and none of them are exactly the same. I suspect that many machinists have made replacements over the years, or maybe the factory changed (beefed up?) them at some point and with the poor record keeping at Bellanca, no one would ever know. ____Grant. P.S. does anyone know of a source for a simple overpressure relief valve that isnt sized for a backhoe? The Cruisair hydraulic gear is supposed to have one and mine doesnt. I can find huge ones, but not something that matches our line size. Most of the hydraulic gear Cruisairs are missing it.
 
I just had another thought. I believe that the brackets on the Master are the same as the early Viking. Maybe a call to one of the salvage yards might locate one quickly. There are many more Vikings in the salvage yards than there are Masters. ____Grant.
 
Lynn, Thanks for the fast response.
I guess I will pull the cracked bracket off and make a drawing of it.
I run a machine shop as my day job, so I may be interested in milling out a bracket as well. What material are you planning on using for yours? I would guess the original is welded up out of 4130 sheet.
I am scheduled to take the Cruisemaster to the avionics shop in January so I really want to get this fixed soon; and I get panicky when there is no airplane to fly;)
 
I have made a bracket to replace the broken right main gear cylinder bracket. The one on the plane had a 5/16” flange bent up, and was .080” thick. The new bracket is .090” thick 4130, with a taller flange that should add to the strength and keep it from breaking again. The clevis portion is .071 on the original and the same on the new bracket.
When I get some time (when the plane is in the air again), I will use the same tooling to make another one for the other side should it fail. If anyone else needs one let me know.
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