MONTY THE ANSWER MAN ARCHIVE 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
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