SWIFT COWLINGS...
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Bob Runge's Cowl Latch Safety
Device
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GC-1A COWLING ON GC-1B...
I know that you will love this one. I was just looking at some of the beautiful
Swifts in the photo collection that is part of the Swift pages when I noticed
that the information describing N8888, Bill Whenchel’s airplane, indicates
that he is utilizing the cowling from a GC-1A (85 H.P.) Swift modified to
go on a GC-1B (125 H.P. & +) engine. It sure is a fine looking machine.
But, this trick was done in about about 1953 by my buddy Joe Zito of Baltimore,
Md on Swift N90806 when he installed a C-125 engine in his “85”
Swift. It worked out so good that when I modified N90305 I did the same thing,
except I got caught by the FAA’S man in Maryland, Inspector
W.G.”Bill” Kelley. It was necessary for me to get a Supplemental
Type Certificate (STC) to get it back in the air. I was issued STC No. SA1-82
in 1957 to cover the installation of a Continental C-145-2H and the cowl
modification, on the GC-1A airframe. I don’t think that anyone would
have a use for this certificate now, but if someone needs a copy I will be
more than happy to E-Mail it to them.
Larry Simms (larrys@abs.net)
BEEF-UP THOSE HINGES... (9199)
I need a set of steel cowl hinges for my 1948 Temco GC-1B. I have aluminum
hinges and have had to reinforce both due to cracks. I want to convert to
steel hinges. Anybody know of a source? Steve Roth N2397B
Steve: I don't know who might have some, but I have fabricated them. Make a paper pattern. Transfer it to a sheet of 4130 the same thickness as the aluminum hinges. Cut out on a bandsaw and drill the hinges, break 90 degrees same as the old hinges. -- Jim
FILLING-IN THE GAPS... (11299)
Subject: Re: Exhaust Stack/Cowl Clearance
To: Richard Aaron <raaron@pica.army.mil>
In the course of doing some cosmetic surgery on my cowl, I'm cleaning-up
the openings which the exhaust stacks pass through. What gap is sufficient
to allow for engine vibration while minimizing air loss? Are there any ways
to provide a seal (with a floating aluminum "washer" around the stacks and
inside the cowl or fiberglass maybe)? Also, I have the original style latches
which don't totally thrill me. Is there any history of problems with these
or any hints for adjusting? I have 1 or 2 ideas for adding a safety. Has
anyone come up with something before? Also, I'd like to add a quickdrain
for the oil; do you know the thread size and if they're available (from Data
Plate: C125-2, Quote Engine Number 8186-8-2)? I've also wondered about the
nomenclature difference between C-125, C-145 and 0-200, 0-300. Is the C-125
equivalent to an 0-200 and a C-145 equivalent to an 0-300? Lastly, I'd appreciate
an e-copy of the 0-300 manual. By now you can probably tell, I'm having a
slow morning at work!
Dick,
You probably want certain amount of leakage around the exhaust stacks which
would allow heat to be dumped overboard. Having said that, I did rig up a
stainless steel floating seal once which I'm sure cut the air loss and did
not appear to cause much of a rise in cyl head temps. My present Swift is
all stock and is not optimized, but I'm just content with it the way it is.
The stock latches have come open and caused the loss of several Swifts. I
also have the stock latches, but I safety wire the front two for every flight.
You want the detent to lock in positively when latching. But I still safety
wire them! The C-125 and the C-145/O-300 have a different thread for the
oil drain. I'm sorry, I can't tell you off hand which one you might have,
besides, I think some 125's had the same thread as the O-300. You'll just
have to look at what you've got. The 125 is like a 6 cylinder 85, both engines
have the same stroke. (3 5/8") The O-300 and C-145 are like a 6 cylinder
O-200, they have the same stroke. (3 7/8") -- Jim
INTERESTING AVIATION USES OF COMMON GARDEN HOSE AND HARDWARE STORE SPRINGS... (11399)
Subject: Swift Cowling
From: Ed Lloyd <edlloydaustin@juno.com>
Howdy Jim.
Recently I've noticed the top cowling on 3856K raises up 3/8 to 1/2 inch
in flight on the rear at higher speeds. The part that moves is between the
center hinge point and where the cowl starts to curve down around the outside
of the fuselage. I have the original Swift cowling. I raised the cowl and
looked it over good and it appears that the problem is created by air pressure
from within due to the updraft cooling on the O300. The angle stiffeners
along the inner trailing edge of the cowling appear to be too weak and the
inner pressure is pushing the cowling upward in flight. At rest on the ground,
the cowling fits reasonably well. Question is, have you seen this problem
and do you think thicker or stronger aluminum angle in this area would correct
the problem? Ed Lloyd
Ed,
The easy way to fix this is to simply put a short section of common garden
hose over the bolt extending out from the firewall that the hooks grab from
the top cowl. If the cowl persists in riding up, a hardware store spring
can be rigged up to pull it down. As a last resort, a couple of Dzeus fasteners
can be installed in the top cowl aft edge. -- Jim
SECURING STOCK COWL LATCHES... (11399)
From: Richard Aaron <raaron@pica.army.mil>
Subject: Re: Exhaust Stack/Cowl Clearance
As to the original cowl latches, this is the only thing keeping me on the
ground now. I have them off to try to work out a safety. I wanted to clarify
weather past failures were due to them just opening or if there were part
failures. Right now I'm intending to prevent them from unintentionally opening,
but if part failures were involved, I might opt for a completely redundant
latch (looks like it had some previously). Originally, there were no detents
so I filed some at the bottom of the "grooves", which helped a lot. I am
also curious as to exactly how you manage to safety-wire them. Thanks again.
Dick,
I have some AN3 bolts installed near the latches, one nut on each side of
the cowl skin. I have some small holes drilled in the latch handle, but you
can just as well wrap the wire around the handle. The latches just open,
the failures have been with the aluminum hinges between the top cowl halves,
these should have been replaced by steel parts years ago. If you have aluminum
hinges, I strongly suggest you replace them with steel. These used to be
available (cheap!) from Univair, but I suppose fabricating your own from
4130 or any steel is the only option today. (I just had a friend make me
a pair last week) I have also rat-tail filed detents in my latches. What
happens, an airplane is out of service for a number of years, then many times
when it is put back in flying condition an AD note or service bulletin gets
missed. Those hinges never were an AD note and they never made the "official"
service bulletins, as published. I rebuilt s/n # 8 some years ago and it
had not flown since 1952, several old AD notes had not been complied with.--
Jim
BOB RUNGE'S COWL LATCH SOLUTION...(11499)
Swifter Bob Runge wrote the following on the Yahoo Globe Temco Swift Club
site...
"Been reading about the stock cowl latches coming loose in the Internet News
letter etc. and thought I'd share the setup N80528 has on the latches. My
stock cowl latches have small holes drilled in the handles. Then when closed,
the latch handles bump into small studs that also have holes in them. These
studs are mounted at the very end of the latch handles detented travel. Then,
through the holes is put a cowl safety pin (Aircraft Spruce new catalog page
98 item #AN 416-1 or -2. The pin latches just below the through hole side
of the stud, therefore not allowing any upward travel. It's clean, neat and
easy to deal with going in and out of the engine compartment." Bob Runge
<ejectr@javanet.com>
(Click Here to see photos of Bob's latch safety
device...)
COOLING DRAG IN “STOCK” SWIFTS...
Swifter 77759, as well as the folks he referenced, are correct, a large portion
of parasitic drag of a reciprocating engine powered airplane is cooling drag.
The two rules on mods to my plane (N3378K) have been 1) no new holes in primary
structure or difficult to replace parts (wing fairings, engine cowl etc.);
2)no visible changes to the exterior (well, from ten feet or so).
As well as the usual holes and loose pieces, three of the major leaks on the Swift cowl are around the exhaust stacks (inside the high pressure volume internally and close to the lowest pressure areas on the cowl externally), behind the spinner (leaking out of both the upper and lower plenums, as well as between them), and around the carburetor heat dump vent on the bottom. I built silicon baffles (the blue stuff) for these areas, using nomex cord between the stacks and have noted minimal deterioration in a couple of hundred of hours over the last two and a half years. I noted even larger gains than 77759 when I accomplished these changes, with cruise speed up from 130 to 145 at 8,000 feet or above. Rebuilding the tired engine at the same time likely helped a lot too, unfortunately making separation of the two effects difficult. I gained an additional 5 mph and 80 RPM at max power at 3,000 feet by adding a control to the cooling flap and an exit ramp onto the lower corner of the firewall. From an old NACA report on jet thrust from the piston engine exhaust I calculated there is about 12 lb. of thrust (about 5 hp. at 150 mph) lost do to the strait stacks. With suitably shaped ejector nozzles an additional 2 or 3 mph could result. The major gain, however, would be an increased rate of climb, up about 60 feet per minute, and best rate of climb speed would be biased up a couple of mph to boot. I haven’t gotten beyond the analysis/sketch point on this mod and it would violate rule 2, but it would look cool (P-47 like) and would bolt on/off, so fudging may be in order.
The other major drag source is the “goofy, toothy grin. It’s much
too big (by a factor of about three) and it’s spread out all over the
pressure distribution around the front of the cowl. It would be interesting
to tuft the grill and see if air is exiting the cowl at the upper outboard
areas. Anyone have any data? Unfortunately it is out of the question for
me as the whole character of the airplane would be changed. As Lopresti
says, “Fly fast, life is short” or something to that effect.
Jared Smith, WA (jedswift@aol.com)
MATERIAL GUY... (12199)
Subject: Re: Baffle Material
From: Bud England <Dalswift1@aol.com>
What are you using for baffle material on original cowls? The red,orange
and blue silicone stuff seems too pliable. The old black stuff with the
fiberglass thread--well, I was never convinced that it sealed that well.
I really want to seal it up the best I can. -- Bud
Bud,
Joe still has the original type down there. When I put my new engine in a
couple of years ago, I bought a set of the original baffle seals from him
and used some of those and some newer stuff in several locations. Like you
say, some of that silicone seems a little too pliable, but I think you can
figure out a combination that will work out. -- Jim
NEEDS ORIGINAL STYLE COWLING HANDLE... (080201)
Subj: handle needed
From: marvin@accesstoledo.com (marvin-h)
Jim, I need a part. If anyone has a cowl closing handle for a stock cowling, I
need one. One of mine broke real bad, not repairable. You do not fly without the
cowling latched down so I need one real bad. -- N80740 Marvin Homsley
Marv
If it is the handle that is broken an interior handle from an antique auto may
substitute. I think a 1934 Ford used much the same type handle. If the steel
hook is damaged it might be repaired by welding or maybe some kind hearted
Swifter has a used one and he will offer it to you. -- Jim
STOCK COWL VS MODIFIED... (080301)
From: vincelc
Subject: Stock vs modified cowl [Yahoo! Clubs: Globe Temco Swift]
I've seen Lycoming and big Continental powered Swifts with either stock cowlings
or Corben or other style cowlings. How much speed improvement does a modern
cowling make for a given engine installation?
A clean downdraft cowl CAN help give a speed increase, but there is not much
difference. A stock cowl with a baffle for downdraft cooling will be very close
to a fiberglass cowl in speed. SuperModified cowls such as the one Scott
Anderson put on N80555 or the ones Jack Nagle made up with the round inlets go
pretty good. Also, the SwiftWorks modified stock cowl with the downdraft nose
seems to work great. A stock 145 with a stock cowl may be faster than a cleaner
downdraft cowl 145 because the carburetor is located in the high pressure
cooling air plenum and the engine may simply be getting more manifold pressure.
-- Jim
MORE COWL STUFF... (080301)
Subj: Cowls
From: Doc Moore <darladoc@sport.rr.com>
Jim:
3817K's 180 Lycoming is getting an overhaul and while that's going on I would
like to change cowls. I was emailing with Sam Swift concerning his cowl and he
says the paperwork indicates that its a Swiftech. Can you tell me who made or
makes that cowl? A fellow in Florida has a brand new cowl for sale but he
doesn't have the paperwork on it. I have seen some cowls with no scoops on them
that have carburated engines so am wondering how the induction system is
plumbed. Do you have any knowledge of this? Thanks for your help. Doc Moore
Doc
I think yours is a Swifttech, so you all ready have the paperwork. Hank Rill has
one, (727)797-1008. Also Jon Breese has one, (402) 697-8302. Be aware there are
different styles for Continental and Lycoming engines and there is also one with
no carb inlet for fuel injected TCM IO-360. The only versions that were STC'ed
were for the 145 Continental and the 150 Lycoming. Swift Alterair in San Diego
made these cowls, I don't know if they are still making them or not. They had a
link off the Swift site. The last phone number I had for them was (619) 463-9057
home and (619) 565-2131 work. (Frank Verbeke) -- Jim
COWL QUESTION... (JAN 04)
Subj: Corbin cowls
From: Larry LaForce <LaForce55@aol.com>
I have a question about the Corbin cowlings. How much heavier are they than the
stock Swift cowl? I know they have to be some heavier because of their age and
the glass techniques of that era. I'm sure the modern fiberglass cowls might be
a little more inline with the stock weights. I was admiring the pictures of
Mick's and Bruce Ray's birds with the Corbins on them. Thought that might be
something I wanted to pursue and I thought you could enlighten me a little. Ed
told me that is the reason he stayed with the stock cowl is because of the
weight. Thanks and hope you are feeling well. Larry >>
Larry
The Corben cowls are "a little" heavier than the stock cowl but I
never weighed them to determine exactly how much. They are made with a quality
fiberglass and I think are quite comparable to newer airplanes with fiberglass
cowlings. Mick Supinas hanger neighbor has a new Cirrus and I think Micks cowl
is just as good. I prefer the stock cowl if it in good shape but the Corben (Alterair)
is more efficient. We had both a Corben Cowl and a somewhat worn original cowl
for Micks airplane and we had to choose between the two. We used the Corben Cowl
because we had the whole installation, baffles, oil cooler, etc. We had a chance
to sell the 125 engine we had, but only if we included the original cowl. (C-125
engines are not easy to sell!) I would not worry about the added few pounds of
weight. Alturair may have lost their PMA to make the cowlings. If you are
interested in one, call them, their number is on the Swift site. -- Jim
(Alturair’s contact is Paul Ross <ross9290@aol.com>1405 N. Johnson Ave,
El Cajon, CA 92020, (619) 449-1570)
FIBERGLASS COWL WEIGHT...(MAY 04)
Subject: Re: May #1 GTS Internet Update
From: Mick Supina <masupina@mmm.com>
Someone a few months ago was interested in the weight of a Corbin Cowl. During
my recent annual I weighed mine. I can't remember who needed/wanted that
information. If you could publish or pass along the information, I would
appreciate it.Top piece: 12 pounds. Bottom section: 18 pounds. Total weight of
cowling: 30 pounds. -- Mick Supina