Swift Airframe - Horizontal/Elevator

REBULIDING HORIZONTAL STAB... (080100)
Subj: Re: control surface balancing
From: Michelle Dolin <swiftgal@hotmail.com>
Hi Jim, We are in the process of rebuilding the horizontal. We have to replace the forward channel piece, that ties the 2 forward spars together, and the trim cables run through it. Is there a trick to getting the trim cables off? We can only see one attach point for the cables, and it has the spring and the safety cable attached to it. It sure would be great, if we could get the cables off, without having to unwind the assembly... Thanks -- Michelle

Michelle,
At the cable drum in the left horizontal it is necessary to tightly wrap the cables with duct tape or make cable blocks with two pieces of wood and a screw to hold the cables on the drum and prevent them from "birdnesting." Then you must go in the aft fuselage and remove the tension spring and cut the safety loop. Then pull the cables free, after removing the stop blocks, pulling the one around the trim crank pulley. You may want to remove the whole trim mechanism from the aircraft next. Somewhere along here you will remove the stabilizer from the aircraft. I presume you can figure out the sheet metal procedures to replace the center spars. -- Jim

WHERE THE DEER AND THE ELEVATOR PLAY... (090300)
Subj: Where the deer and the elevator play
From: Terry Straker <TASGuitar@aol.com>
Hello Jim.
Hope you are feeling well. I am feeling great as I finally got the Swift back in the air today. However, during the annual today, the IA asked if I knew spec as to play in the elevators. Mine have a little up/down motion relative to each other. I searched all books to no avail. Am I missing a tolerance published somewhere, or thru your experience is a small amount of play normal? The play seems to start where the rod ends in the push/pull tubes attach to the bellcrank. When the trailing edges of the elevators are pushed up or down there is about 3/16 inch of play relative to each other at the trailing edge. Do I need to be replacing those rod ends? Or tightening the castle nut and bolt that attaches the rod end to the bellcrank? There doesn't seem to be any problem in flight--and I do want to keep it that way. Your insight is, as always, very appreciated. -- Terry Straker

Terry,
You won't find much published re: wear tolerances. The gear wear limits are in several AD notes. The elevators can be evaluated one bearing at a time. Are the 3 hinge bearings OK? They seldom show wear until they disintegrate from age or rust. There are rod end bearings at the ends of the elevator push/pull rods. Take a look at how much free play exists. Having said that, the problem is probably an AN3 bolt on the elevator horn. Access is by crawling in the aft fuselage. Remove the AN3 bolt which connects the two elevator push/pull rods to the elevator horn. Inspect the bolt for wear. If it is not worn, I suggest you replace it anyway. You will need a cotter key puller and a couple of 3/8" wrenches. Just tightening this bolt up will usually get rid of any excess elevator play. What happens if this bolt is at all loose, when one elevator is deflected down, the other elevator goes up slightly, just what you describe. If you tighten that bolt, I'm sure your problem will be fixed. -- Jim

SPRING HAS SPRUNG...(070501)
Subj: Elevator springs
From: Ron Williamson <rwwilliamson@earthlink.net>
Monty,
Bill Weaver and I were having a discussion about elevator springs since the aft facing one broke on 238. As I recall when I first acquired 40K, it had only one spring. I don't remember exactly why I put one facing each way when I reassembled things, but it works well and keeps the elevator centered, especially with the light controls resulting from the Lischer stick conversion. I'm sure you know the history and probably have explained it one or twelve times. How about once more? Ron Williamson

Ron
The parts catalogue only shows one spring. I too, installed springs both directions many years ago. I only have one in my present Swift. The 210 STC calls for removing both springs. Quite frankly, I don't know all the reasoning for the springs. I can see the centering effect and the bungee effect and I think the one spring may be there for a certification requirement. (maybe it should be called a "downspring.....". Perhaps someone familiar with the engineering will enlighten us. -- Jim

TIGHT ELEVATOR CONTROL... (070501)
From: Harlan Walker <HWalker@wii.com>
Subject: RE: July #4 GTS Internet Update
Dennis I have another problem, My elevator control is tight, as if I have a bearing not free in one of sheaves, I have checked them pretty closely and have not yet found anything. Harlan

Harlan
Strange you should ask that question today as that's the thing I intend to look at today on our project airplane, N80796. The first thing I will look for is excessive drag and lack of lubrication where the control yokes slide on the phenolic bushings in the instrument panel. Then I will look the cables over for alignment, tension and stuck pullys. Also, the general alignment of the cables under the panel. If necessary, I will disconnect the cables and try to determine where in the excess drag is coming from. I have good intentions to do that today, but It is supposed to be very hot and I may not get to it. I will let you know what I find, when I solve that problem. -- Jim

(Editor says: LPS works good for me on anything that hinges, pulls, spins, and rubs in the control colums and linkages up under the instrument panel and
 elsewhere.)

SPRING IS IN THE AIR... (080201)
Subj: Question
From: Swift238
Hi Jim,
I broke one of the springs on the elevator horn. Do you know where to get these? I tried the Assoc. but so far no joy. I noticed the parts book shows one spring but I have two ( Lischer sticks). I would like to buy two new ones and a couple of spares. Hope you can solve the mystery. Thanks, Bill

Bill
I suspect the springs were not an AN part when the airplanes were first built. I would match up the remnants of the spring you have with the inventory at your local hardware store. There might be a screen door spring that is similar. If you find one that is the right diameter but too long it can be shortened and a new hook fashioned at the end. Some of the Merlyn STC's call for removing the spring, so I suppose the spring is not real critical. -- Jim

ELEVATOR CONTROL HINGE WASHERS... (090301)
Subj: Question :
From: Bill Doty <wdoty@seidata.com>
Jim, I am reinstalling the elevators and have a question. I have the bevel washers that supposedly go on each side of the bearings... There is not sufficient clearance to allow the washers without bending the attachment points on the elevator... I would have to spread the attachments by .080--.100 ?? This would throw the faces of attachments drastically out of parallel... There does not seem to be any previous distortion .. Appreciate your help , as always... Bill Doty N80572

Bill
The elevators do not require those washers. The ailerons & flaps do. The elevators use K3L bearings, the ailerons and flaps use KS3L (S=Swivel) The rudder is the same as the elevators, K3L bearings. The swivel bearings at the ailerons and flaps need those beveled washers. -- Jim

GUESS HALF A HOLE IS BETTER THAN A WHOLE HOLE... (110401)
Subj: Horizontal
From: Larry LaForce <LaForce55@aol.com>
Hello Jim...
I have a question about the Horizontal mounting. Is this suppose to be a precision fit...or do they sometimes need some gentle persuasion? The previous owner of 80844 had made and installed a new rear attach fitting. The fitting is an exact copy of the old one. There is some slight misalignment at the rear attach fitting with the 4 front bolts in position. It is off about half of the hole. Is this normal...or do I need to re-do the rear attach fitting to get perfect alignment? Thanks.... Larry

Larry
Only off a half a hole? Thats pretty good! Just put a tapered punch in there and pry it into alignment. -- Jim

HORIZONTAL REAR ATTACH FITTING...(120101)
Subj: Tail feathers
From: LaForce55
Jim...Was it customary to change the horizontal rear attach fitting when converting a GC-1A to a GC-1B? If not....do you feel that it is worth the trouble to lower the rear attach fitting hole the 1/4 inch? I'm afraid that the fitting I just installed on 80844 is the GC-1A style. Thanks... Larry

Larry
It is not necessary. If you end up with an airplane that cruises at 140 mph or more you might have to carry a little nose down trim. If you can see the elevator balance weights in flight, that indicates the elevators are trimmed "down". You can always drill a different hole in that fitting later to permit the trim tab to fair in cruise. -- Jim

STIFF ELEVATOR...(120201)
Subj: Request advice
From: Dale Severs <dsevers@autpro.com>
I recently purchased a Swift, and have a "stiff elevator" in that it stays where it is put and expect it should move more freely. Noticed a similar question but no answer yet. Is there a typical location that causes the drag in the system, or is it more a matter of troubleshooting on a case by case basis. Are there cable tension spec's for the Swift? Best, Dale S

Dale
Most times the drag is caused where the tubes for the control yokes go thru the panel. You can simply lubricate them with silicone spray. Or you can substitute the phenolic bushings in the panel with Teflon or such. Caution: the stock panel is at a 7 degree angle. I have teflon tape applied to my tubes. Others have found teflon "roll wrap" -- designed for printing press rollers, the correct diameter, and after removing the yoke and panel bushing, slipped it over the tube and then shrunk it to the tube. Lubricate all the pulleys in the elevator system. There is a bungee spring installed near the tail -- see the parts book. Some Swifts have had two bungee springs installed mistakenly by previous owners who thought them necessary for elevator centering. The Swift Operators Manual calls out the cable tensions. The elevator cables are 20 lbs. -- Jim

SPRING HAS SPRUNG...(NOV 02)
Subj: Spring Question
From: Bill Weaver <Swift238@aol.com>
Hi Jim, I have not been able to find a suitable replacement spring for the elevator. One broke and the other is causing the thing to be unbalanced. Can I just take the other one off and have none? Is there any problem with this? Thanks in advance. Bill

Bill
The parts catalogue only shows ONE spring. Over the years evidently several owners have figured there should be two springs to make a "centering spring". Evidently, the one spring is a "downspring". Hugh Evans IO-360 STC calls for the removal of the spring so it must not be real important. -- Jim

N3741K HAS A NEW CARETAKER... (JAN 03)
Subj: Globe Swift Elevator question
From: Henry Dittmer <hdittmer@avaya.com>
Jim,
I recently purchased N3741K from the estate of Gerald Becker. I'm really excited to own a Swift! The airplane is in Wichita, KS. In the process of getting it ready to fly to Denver, I noticed that the elevator stays in any position that you place it, as opposed to dropping down. We removed the tube assemblies that run from the bell crank to the elevator in the tail. The elevator, once disconnected travels freely. However, we noticed two springs attached to the bellcrank. These are rigged in an opposing manner, such that it explains why the elevator would stay in any particular position. Is this normal, or has this been a past maintenance mistake. I don't see any springs on the drawings in the parts catalog or owners manual. Is there some other manual I should be using as reference (I bought the complete set from the Swift Foundation) Thanks in advance for any advice, Henry

Henry
If you go back through the logs to about 1980 you will find I did some work on N3741K then. Also, I flew it some at that time, it was a nice airplane! The elevator spring question has come up several times before. The parts catalogue shows just one spring. See figure 21 on page 36. The spring is item 10. 11-532-3271. The spring acts as a downspring, pulling the elevators down. I have seen two springs which would be centering springs, such as you have. I don't know if those are "factory" or not. With both springs on there the elevator will return to more or less a neutral position. The springs are not critical as several of the "big engine" STC's for the Swift call for their removal. I don't think the two springs are any cause for alarm either. I've been told a downspring makes an airplane cruise faster. Bill Weaver has some knowlege of this, I am cc'ing this to him. -- Jim

MONTY HAS AN "INTERESTING FACTIOD" RE: CONTROL SURFACES... (MAY 03)
From: Jim Montague <Swift31B@aol.com>
Subject: Interesting factoid
Denis
Perhaps you remember, some time ago, perhaps a couple of years ago, there was some discussion of the balance of Swift control surfaces. I knew the ailerons were balanced 100%. I still am not exactly sure of the elevators. Today, Mark Holliday had several elevators apart while doing some work on an elevator tip. They are different! Some elevator tips weigh 3 1/2 pounds and some weigh 4 pounds. This is mostly in the lead balance weight of course. What this means as far as the percent of balance I'm not sure but I think it is interesting. -- Jim

ELEVATOR QUESTION... (AUG 03)
Subj: Elevator Tolerances
From: Ed Lloyd <swift3856k@austin.rr.com>
Hi Jim. I've been helping Duane Golding do a stick conversion / installation in Dick Wilfong's 3313K. Something came up yesterday that doesn't seem right to me. I went back today and investigated some more and here is the situation.

With one side of the elevator clamped with wood blocks, top and bottom, so it can't move the other side of the elevator will move up and down an inch and a half! I went and did the same thing to Duane's Swift and basically the same thing occurred with movement of about an inch. I then went to Dorothy's airplane and checked hers and it was the same as Duane's bird. Went next to my bird and checked it the same way and it had way less movement, roughly 1/2 inch up and down. If you stand directly behind the airplanes and move both sides of the elevator simultaneously, I can move one side up while the other side goes down! I crawled in the aft section of 3313K and double checked the elevator bellcrank installation which was changed out during the stick conversion (Thomason STC) and all appears normal where the elevator push / pull rods are concerned with one possible exception. With a person moving the elevators from outside and me looking directly at the bellcrank, the bolt that attaches the push / pull rods (tube assembly) to the bellcrank, was moving back and forth (fore and aft). The bellcrank that was installed during the conversion had the hole drilled for the tube assembly and rod ends and a bushing pressed in. I had checked the bolt before hand and it is the correct size.......but that motha is allowing the rod ends to move and it's TIGHT. Strange, at least to me. Duane has the fuselage of the Swift he just bought from Vaughn Armstrong at National sitting in the shop. This Swift has sticks installed (Leischer STC). It has all the "tail feathers" removed and just the tube assemblies protruding out of the fuselage from the elevator bellcrank. They do not move fore and aft like the other three Swifts we checked.

Can you shed any light on what is going on? Is there any movement allowed from one side of the elevator to the other? It would seem to me the situation could lead to elevator flutter. I have flown Duane's and Dick's airplane and of course mine to redline many times, and there is no hint of anything wrong with the elevator in flight. Cheers........Ed Lloyd

Ed
I have seen that many times, where if one elevator goes down, the other goes up. That is caused by the little AN3 bolt being loose where the two elevator control push-pull rods fasten to the bellcrank. Sometimes the bolt is worn. Remove the bolt, inspect it for wear. Also check the bellcrank -- it seems to me there is a bushing in there, replace or rebush parts as necessary. Reassemble and be sure that bolt is tight. -- Jim

SOME TEXAS SWIFTERS NOW HAVE TIGHTER TAILS... (AUG 03)
From: Ed Lloyd <swift3856k@austin.rr.com>
Subject: Elevator Tolerances
Hi Denis. We got to the bottom of the "shaky tail syndrome". Dick Wilfong and I went to the airport yesterday and we readdressed the problem that was allowing opposite sides of the elevator to move up or down. The bolt attaching the elevator tube assembly to the bellcrank was too long! The bolts were tight, but simply too long allowing the nut to get "tight" on the shank of the bolt and not tightening up against the sides of the elevator bellcrank. Three of the four Swifts checked had AN3-17 bolts installed in the elevator bellcrank / tube assembly and the correct length bolt should be AN3-15A. I changed out the bolts, added the approprite type and number washers and the Zuehl Swift Fleet has the "tightest tails" on the planet. Thanks......Ed