Published Quarterly (Jan., April, July, Oct.) by:
Co-Z Development Corp.,
2046 N. 63rd Place, Mesa, AZ 85205
TABLE OF CONTENTS
It is mandatory for all Cozy builders to have Newsletters #4 thru 24, plus a current and continuing subscription to future editions. We are attempting to get this edition published a little early so we can wish all of you:
Also, please note the re-availability of Cozy flight apparel, in case you have Some last minute Christmas shopping to do (They also make excellent birthday gifts). Co-Z Development provides support directly to Cozy builders in the US and Canada; and all other countries indirectly through our good friends:
Co-Z Europe (Uli & Linda Wolter), Ahornstrasse 10, D-8901 Ried, West Germany
"I envy Vance for his spare time to accomplish all these nifty mods and changes. It seems that we just do not have enough time to do all we want. In your newsletter you stated that we had a variable pitch Hoffmann propeller on our Cozy. This was not correct -Please note -It is a MT (Gerd Muehlbauer) electric variable and constant speed propeller, e.g. you may select any position you want and after selected, this pitch setting will stay regardless of power setting. In the automatic mode, however, the propeller will maintain the selected RPM like any C/S propeller. On take off, I select 2700 RPM and after take off I reduce to 2500 RPM or what ever propeller speed I desire. This gave us a take off roll of 440 m or 1340 ft. with a gross weight of 1710 lbs. at sea level and calm winds during the EURO CAFÉ 540 this summer. By the way, we won the race again this year by beating a Glasair.
.I also mentioned in our last newsletter what we have, done with our Roncz canard. Since we cannot afford to take the Cozy in the shop during the flying season, I did not continue testing at aft c.g. positions past 100.5. During this winter I will increase the canard incidence by 0.5 degree and hope to have 0 degree elevator at mid c.g. with 160 KIAS cruise speed. More thorough testing will then follow."
Uli sent me literature on MT propellers. In USD the propeller costs $4,300 and the control unit $820. It was not clear whether this was delivered cost, or shipping and duty extra.
Those of you who also subscribe to the "Canard Pusher" ($14.00Iyr.) will note that we sometimes cover the same subjects. This is particularly true in this issue; there were a number of good articles in CP #57.
ANOTHER COZY FLIES:
We heard indirectly that S. Morgan Dean, in Burbank CA has finished a beautiful Cozy and is now flying off his test hours. We tried to confirm this by phone, but he apparently has an unlisted number. How about a written report, Morgan: Also, if any more of you are flying, please let us know so we can keep other builders up to date.
Keith Spreuer writes:
We had an incident in our Cozy N84CZ of which I thought you should be aware. The incident involved a nose-gear-first landing that, fortunately, resulted in very minor aircraft damage and no injuries.
We have a total of about 60 hours on the airplane so far and have been very happy with its handling and performance. We have been concerned with the relatively high takeoff speed at forward c.g.s, however. We took off at a gross of about 1400 lbs. and a c.g. of 98.2. We had a beautiful flight for about 2.7 hrs. which reduced our fuel down to about 6 gals. and put us at a c.g. of 97.6. We pulled the power to idle 10 miles from the airport at 5,000 ft. AGL and had an easy glide to the airport. I trimmed the airplane for a steady 700 fpm descent at 80 KIAS. Everything appeared perfect until I tried to flare. I pulled hard on the stick but got no noticeable change in pitch attitude. The airplane contacted the runway on all three wheels at the same time, or possibly a split second sooner on the nose. The landing was hard, but not as hard as I've seen in other aircraft. The nose gear collapsed immediately. The airplane lowered its nose to the ground and slid straight down the runway and stopped in about 200 ft. There was no discomfort to myself or my passenger.
Later, when we inspected the plane, we believe the following failure mode occurred. The first failure was the two lower screws that hold on the nose wheel assy. Before the other two screws failed, the rod ends on the shock strut buckled and the gear folded up until the wheel contacted the bottom of the fuselage just forward of the wheel well. The wheel assy. then came off entirely and contacted the prop. The NG-l strut never retracted entirely and acted as a skid, so that there was no damage to the fuselage. The retraction mechanism remained down and locked, there was no damage to the large spur gear. The tube through the center of that gear was bent, causing binding when near the full up end of travel. We replaced that tube, the shock strut and rod ends. The NG-l strut was ground down about 1/10 in. below original size, thru the BID plies and into the uni-S-glass. We laid up 2 plies of BID over the front of the strut and reinstalled the nose wheel assy. with AN hex head bolts. These repairs and a borrowed prop were adequate to ferry the plane back to home port. We are now replacing the NG-l strut and making cosmetic repairs. other than returning the configuration to 'per plans' we are using AN bolts at the top and bottom of NG-l and putting an 1/8" steel plate in place of aluminum on the NG-5 attachment. We also squeezed an extra 1/4" in length on NG-l to increase angle of attack during takeoff. We are considering a stiffer spring in the shock strut so that the gear compresses less at forward c.g.s, also improving angle of attack during takeoff. We understand that this spring is available but we have not ordered one yet. We sent the prop to Great American and to our surprise, it is repairable ($100).
So, what is the reason that the plane didn't flare? I think I would have to say, pilot error. Examination of the trim, after the accident, indicated it was not near full nose up. I believe that I was not out of elevator travel, but that due to the stiff trim spring we have, the forces were so high that I thought I was. We have a non-standard pitch trim system using a fiberglass cantilever spring and push rod on the torque tube instead of the double spring set up. our spring was too stiff to get full travel of the elevator when the trim is in the center position. The take-off and landing speeds were higher than we liked at a c.g. of 97.5, so we also moved the battery from the nose to the center spar so we are not on the forward c.g. limit with two people in the front seat. That means more ballast when I fly alone, but I think that is a better compromise. You should advise builders to keep the landing flare in mind when they evaluate forward c.g.s.
Sincerely, Keith Spreuer
I talked to Bill Spreuer after this incident. He and his son had originally installed the battery in the nose to minimize ballast when flying solo. However, when flying dual, they were very close to the forward c.g. limit, which gave them a nose-down attitude during takeoff, extended their takeoff distance, and required more nose-up elevator during landing. They had checked forward c.g.s during the test period, and had been flying dual with forward c.g. since without problem.
On this flight, however, they were testing power-off gliding range from 5,000' to touch down, and had trimmed the airplane for 700 fpm descent at 80 knts, and did not slow down to 70 knts on final (Owners Manual p.17), so they contacted the runway at an excessive speed and rate of descent.
Bill said that afterwards they tested their leaf spring pitch trim and found the spring constant to be 5 lbs./in., which required a heavy stick force to override. They have since modified it to 2 lbs./in. They have also moved the battery aft so they will have a more favorable c.g. position when flying dual.
The use of a fiberglass leaf spring for pitch trim has not as yet been recommended as a design change. Although simple in concept, it obviously should not be too stiff, and the friction nut must be adjusted so the trim can be overridden, without excessive force, and elevator travel not restricted.
The best flying qualities are obtained in the mid c.g. range, and your airplane should be balanced to be at midrange when flying dual. You will need ballast in the nose then, when flying solo. Although you can safely fly at forward c.g.s, it will extend takeoff distance and will place additional loads on the nosegear, obviously. There should be no problem flaring, if full elevator travel is available.
AVIATION CONSUMER magazine has reported that experimental home-built airplanes have a worse accident record than factory-built airplanes (even though a large percent of factory-built accidents are stall-spin related). This is due to a number of factors. In home-builts, there are more opportunities for non-conformity to occur (unintentional and intentional). Therefore, each home-built airplane should be considered a new, experimental, research, high-risk airplane. These aircraft are often tested (or even worse, not fully tested) by pilots who have very little time in type, and who often do not follow careful flight safety procedures in their testing. Also, because these airplanes have higher performance and are more fun to fly, many accidents are the result of high-risk flying and improper acrobatics. RAF reports that seven of eleven Long EZ accidents occurred during low altitude buzzing or acrobatic maneuvers.
Make sure you follow the instructions in the Owners Manual for weight & balance, preflight inspection, pilot qualifications and flight testing. Make sure you observe the limitations on gross weight, c.g., maximum speed and maneuvering speed. Acrobatics and low level buzzing are STRICTLY PROHIBITED:
In CP 57, RAF reported a fatal accident in a Varieze, which we mention here because it also relates to the Cozy. The Varieze crashed in Central California because the canard failed structurally due to flutter. In their investigation, the FAA and RAF determined there was a combination of causes.
1) NEVER allow yourself to be distracted while working on your airp1ane, such that you might not complete a task, and then forget to finish it later. We all have had the experience of visitors dropping in while we are working. Even if you have to be rude, finish the job before laying down your tools.
2) Your elevators should balance with the weights shown in the plans. If they do not, do not try to balance them by adding weight inboard. Instead, discard them and make new ones more carefully to make them lighter (you can probably re-use the torque tubes and other hardware). The mass balance called out for the elevator and the specification for balancing them applies only to an elevator fabricated with the same weight and stiffness as that which has successfully passed all the flutter testing. It is extremely important, and life-critical that the manufacturer or owner of each Cozy, or any plane for that matter, assure himself without a doubt, that the control surfaces are conformal to those which have passed flight tests and been shown to be flutter-free.
LANDING GEAR MELT DOWN
You have heard of nuclear melt-downs. Well, it is also possible to have landing gear melt-downs. The cause is the same in both cases, i.e., inadequate dissipation of heat. With the advent of heavy duty brakes, and brake cylinders up front, braking power has been greatly increased. When you brake hard, the discs absorb a tremendous amount of energy, which is converted to heat, and they can get red-hot. This energy can only be dissipated by radiation and/or convection. The gear leg is directly in the path of radiation, and if you install wheel pants without outlets in the top for hot air to escape, all of the heat will be contained inside the wheel pant. The result could be a disastrous melt-down of the landing gear legs. This has happened to a Cozy and at least one Long EZ. There are some simple rules which, if followed, will keep you out of trouble. They are:
SEPARATE TOE BRAKES
Some people think it would be nifty to have separate toe brakes, independent of rudders. We do not recommend this for several reasons. The most important is that you should ALWAYS have full rudder deployed before actuating brakes. There is no situation we can imagine where this is not true. Separating these functions would therefore require additional pilot skill and coordination, to apply rudder first, and then brakes. It is an unnecessary complication (more things to go wrong), it adds weight, and it obviously adds expense. In an airplane, you should ALWAYS use the simplest system which works. Complicating any system increases the likelihood of failure.
NOSE GEAR SHIMMY DAMPER
The shimmy damper in the plans requires religious attention to insure it is tight enough to prevent shimmy, and yet not so tight it overtaxes brakes when taxiing. If not tight enough, a vicious shimmy can occur at high speeds which can fail the fork, and likely also destroy the prop. Bob Davenport has designed, and offers for sale what RAF says is the best solution they have seen (we intend to order one for each of our airplanes). Contact:, Bob Davenport, PO Box 650581, Vero Beach, FL 32965-0581
CS-2 ELEVATOR HINGE BRACKETS
Several builders have reported receiving CS-2s from Brock Mfg. which were out of spec in regard to the perpendicularity of the surfaces, and the bushings located identically in all of the brackets. This is a heat-treated part, and sometimes distortion can occur during heat treatment. Both of these defects can cause difficulties in installing elevators which move freely without binding. We have contacted Brock Mfg. and they were not aware of any problem. If you discover any quality problems, contact them. They depend upon feed-back from their customers. They will also appreciate compliments.
HINGE PIN KITS
Aileron hinges take quite a beating over time from engine/prop vibration and will loosen in time due to wear. Gary Hall sells a Teflon/stainless steel hinge pin kit which solve this problem. The kit consists of stainless steel hinge pin material together with Teflon tubing sized to fit over the hinge pin and inside worn aluminum hinge knuckles. This is said to virtually eliminate further hinge wear. We haven't needed to install this kit yet, but are keeping the information for future reference. Contact: Gary Hall, 4784 NW 43rd St., Lauderdale Lakes, FL 33319, (305) 484-4949
MAGNETO WIRING CHECK
A propeller, mounted to an aircraft engine, is potentially a lethal instrument. It can strike a person hard enough to maim or kill. Propellers frequently must be turned for removal of cowlings, and many other reasons. The ignition should always be off, and the prop should always be turned backwards, against the normal direction of rotation.
The ignition (magnetos) are turned off by grounding the P-leads. This is done with a switch in the cockpit. However, if there is a poor connection, or a break in the p-lead wire due to engine vibration, a magneto can be live even though the ignition switch is off. Then, if the prop is moved in the direction of normal rotation, the engine could fire with tragic results.
It is therefore good practice to conduct a magneto check before shutting down the engine after a flight. To do this, while the engine is still running, turn the master avionics switch off (you have one, don't you?), and then momentarily flip both mag switches off, for only a second or two. If everything is OK, the engine will stop firing, but will start again when you flip the switches back on. Then you can shut down normally, pulling mixture to idle cut off and then switching ignition off. If the engine doesn't stop firing during this check, you have a wiring problem, and your engine is always "live"--a very dangerous situation. Make this mag check mandatory after every flight.
AEROQUIP 601 HOSE ALERT
We recently received a recall notice on Aeroquip 601 hose. Apparently there was a problem curing the rubber, and some of these hoses have been springing leaks with potentially serious consequences.
If you used 601 hose, and made up the lengths yourself between April 1984 and May 1988, you may have defective hose and should replace it. If your hoses were made up by a distributor, they should have a metal identification band. On this band there will be a cure date and an assembly date.
lQ87 = cure date 1st qtr. 1987
A2Q87 = assembly date 2nd qtr. 1987
Look for cure dates between 1st qtr 84 and 3rd qtr 87, which are bad and should be replaced. An authorized Aeroquip distributor will supply you with new hoses, and will give you full credit upon receiving the old suspect hoses.
We have been using Aeroquip 701 hose, which we were told has superior rubber, with no mandatory replacement, period. We evaluated the corrugated, all-stainless steel hoses, and decided they were not flexible enough. RAF is now using and recommends the Teflon "Stratoflex" hose.
Fuel leaks can cause an engine fire, with potentially tragic results. Compliance with this recall notice is MANDATORY:
FUEL VALVE ALERT
The Cozy plans call for the same fuel valve which was specified for the Long EZ; i.e., the 3-way Imperial 108HD-04. This was a metal valve with an unlubricated metal plug. When it was subsequently learned that this valve was susceptible to sticking, when used in fuel systems (which could cause a forced landing), it was recommended in a past newsletter that the 3-way Weatherhead 6749, or better yet, the 4-way 6747, be substituted. The Weatherhead valves have a Delrin (nylon) plug, and, to the best of our knowledge, have solved this problem. RAF reported in CP 57 that there is another satisfactory substitute. It is a Whitey SS-44xF4 valve. This valve has a stainless body, a stainless ball, and uses Teflon seals. It has a .281" orifice thru the ball, and female ¼" NTP threads which accept AN fittings. Flow rate is more than adequate. This is not a recommendation that you replace the Weatherhead, just a piece of information. If you are interested, contact: Whitey Co., 318 Bishop Rd., Highland Heights OH 44143
ELECTRIC FUEL BOOST PUMP ALERT
A Long EZ pilot had a forced landing due to fuel stoppage, even though fuel remained in his tanks. Upon examination of his fuel system, he found the Facet boost pump to be completely blocked. One of the two valves in the Facet had deteriorated, worked its way out of the metal cage designed to contain it, and sucked into a position where it completely blocked fuel flow. The part number on the mounting flange of the pump was 480615. The valve which deteriorated was made of VITON. This pump is no longer being manufactured.
Before your next flight, check the part number of your boost pump. If you have a #40023, 480615, or 480616, remove the pump and replace it.
The most desirable Facet solid state pump for a replacement is #40108 (12 volt) or #40154 or #480610 (24 volt). Both pump fuel at a regulated maximum of 6 psi, and the valves are made of nylon, which may swell slightly in avgas, but are otherwise unaffected and will not deteriorate. These pumps have valves designed so they cannot obstruct fuel flow. The have AN-style 37° flare fittings which fit 3/8" tube, AN 816-6 nuts. Facet manufactures over 100 variations of their solid-state fuel pumps, many of which have VITON or Buna N valves which will deteriorate in avgas. Only nylon is satisfactory for use with avgas (or auto fuel, heaven forbid).
If, after checking part numbers, you are still uncertain, look into the inlet and outlet with a flashlight. Verify that the inlet valve (foot valve) is a round white dome or ball (nylon), NOT a flat, black rubber disc. Verify that in the outlet there is a white nylon valve under a steel pin which crosses the port to retain the valve. If this valve is gray or black (Viton), remove the pump and discard it before your next flight. If you have to have a pump with female pipe threads due to firewall layout, choose one with ¼" or 3/8" NPT threads, rather than 1/8", and examine it closely as described above to be sure it has NYLON valves.
If your Facet pump is more than a year old, you probably have one which could go bad. At a cost of about $30, it is not worth risking a forced landing. This is a MANDATORY change!
Chap.2, p.l & p.5, Chap.21: Change EFP Electric Fuel Pump to Facet #40108 or equivalent with nylon valve parts.
Chap.2, p.2 & p.4, Misc.: Change 108 HD-04 fuel valve to Weatherhead #6749 (3-way) or #6747 (4-way).
Chap. 2, p.4, Chap. 4 Foam: Change (12) to (16) sq.ft. 0.2" thick 18 lb. Clark.
Chap. 21, p.5, Step 11: Delete "and the gascolator & fuel pump in Chap. 15".
Chap. 21, p.5, Fig.16: Change 108 HD to Weatherhead #6749 (3-way) or #6747 (4-way) .
Chap. 23, p.2: Change EFP Electric Boost Pump to Facet #40108 or equivalent with nylon valve parts.
IVHC (INTERNATIONAL VARIEZE HOSPITALITY CLUB)
This club was originally organized for Varieze builders and pilots to visit one another, or to call upon when traveling around the country, and has been extremely successful. It has since been opened up to all composite builders. They publish a newsletter, with the names, addresses, and phone numbers of all members, and organize a number of flying activities for example, flying trips to the Bahamas. They have a dinner-get together every year at Oshkosh. We are charter members, and encourage Cozy builders to join. Membership is $17/yr. If interested, contact: D & B Shupe, 2531 College Lane, La Verne CA 91750.
The IVHC banquet at Oshkosh is getting pretty large and we were wondering whether there would be enough interest to start a banquet just for Cozy builders on either Sat., Sun., or Monday? We would recommend our favorite restaurant, Robbins (excellent food at very reasonable prices). Any interest? Who would like to organize it?
FLIGHT APPAREL AND JEWELRY
Hats: (red, black, lt blue, dk blue, min. order 2)…. .$ 6
T-shirts: (same colors as above, S, M, L, XL)….. .$10
Sweat shirts: (same colors, S, M, L, XL)…………$15
Jackets, flannel lining: (Navy, red, royal, black, maroon, Sizes S, M, L, XL) ………..$42
Jackets, heavier quilted lining:(colors & sizes as above) ……………………………..$47
Jackets, Warm, Sherpa-type lining: (Navy, red, royal, black, kelly, Sizes as above) ….$47
Send money order & $2.00 postage & 4% tax MI residents: Cozy Wear, 7982 N. Masters Rd., Howard City, MI 49529
INSTALLATION OF MASTER BRAKE CYLINDERS IN THE NOSE
Installing the master brake cylinders in the nose eliminates cable stretch and results in much more positive braking. We have also discovered that we don't have to add fluid as often, with cylinders in the nose.
On this page is shown two different schematics. The upper drawing shows how normal Rosenhan, Cleveland, or Gerdes master cylinders can be installed upright. The lower drawing is a simpler installation, but requires acrobatic master cylinders and reservoirs. Both require tabs to be welded on the rudder pedals. Both require rod extensions. The bolt through the rod extension rides in a slot which allows the rudder to be deployed before the brakes are actuated, and the brakes still provide a stop for the rudders.
It is recommended that both right and left brakes be installed on the same side, preferably the pilot's side. Both drawings show installation of the right brake on the left NG 30. If the left brake is installed on the same side, the mechanism will have to parallel the fuselage side. This will require bending the tabs welded to the rudder pedals inboard about 20 degrees. It will also require building a pivot point on the fuselage side. We made a cone ½" high from two layers of birch plywood, sawed on a 45 degree angle, embedded a nutplate in the bottom, (after drilling a 3/16" hole through the center), floxed it to the fuselage side, and covered it with 2 plies of BID, lapping the fuselage side 1 inch in all directions.
The extra slots shown in the brake arm (above) and the tab (below) are optional. They allow you to adjust braking power, if you are not pleased with the normal setting.
Dear Nat, 10/18/88
Just a note to renew my newsletter and to let you know that I am still at it. I have finished the tub, the main spar and one wing. Hopefully, I will have more time in the coming year. I hope the suppliers keep supporting the slow Cozy builders. I really do enjoy building the plane. I wonder if you realize how much pleasure you have brought to your builders. My only regret is that I never had a chance to build the Mark IV, but I sure understand your position in this avaricious society.
Thanks again, Ken Brimmer
Enclosed is $7.50 for another year of the newsletter. I'm still making steady progress; slow, but steady. I believe I have just about finished all the glass work now. I still have fairings and minor additions to make, but most of the remaining work will be finishing and systems installation. There is a growing group of Long EZ and Cozy builders in Chapter 186. The mutual support of a large group of builders is beneficial to all of us. I still find the newsletter to be one of the best sources of information. Keep up the good work!
Sincerely, Dewey L. Davis
Due to recent changed circumstances, I am forced to give up my ambition to build a Cozy. I learned from the newsletter about another Cozy builder, and with heavy heart I sold him the materials I had bought. I would like to sell the plans. Could I ask your help in contacting interested parties? The plans, A drawings, Owner's Manual, and newsletters are all in good condition. My home phone number is (315) 633-9388. I can be reached there except during normal working hours. Between 9-4 I can be reached at (315) 255-3461.
I can't tell you how disappointed I am. May I wish you and Shirley a Merry Christmas and a Happy New Year!
Sincerely, Sakthi Vadivel
Dear Nat, 11/8/88
Just a few lines to let you know how Cozy #300 is coming along. Boy, I didn't expect the finishing process to be as much work as it was. It sure was good for my biceps. The entire airplane is now in primer, except for bottom which is painted with white Deltron. I really like the way the Ditzler K-200 primer with flex went on. It's quite a bit harder to wet sand (more like paint) than normal primer, but really sands to a very smooth finish. I located an engine 0-235-L2C and hope to have it mounted and running in a month or so.
I mounted my master cylinders on the firewall like the plans call for but noted a very mushy feeling when the brakes would be pumped. I called MATCO about this problem and they said a spring added in the lower part of the cylinder would solve this problem. I sent them the parts, they added springs and you can't believe the difference. The brakes are very firm now. I am looking forward to Sun & Fun in the spring. The people to contact about the brakes are: Al Burgander, MATCO Mfg. Co., 65 E. Kensington Ave, Salt Lake City UT 84115.
Thanks, Dave Mendenhall
The following are the ONLY approved suppliers for Cozy parts and materials. The only change since last published is a name change. The Airplane Factory consolidated with its parent company, Fox Lite. There is also a new address and phone number, which is that of its parent company.
Wicks Aircraft, 410 Pine St., Highland, IL 62249, (800) 221-9425
Aircraft Spruce, Box 424, Fullerton, CA 92632, (800) 824-1930
Alpha Plastics, 8734 Daffodil, Houston, TX 77063, (713) 780-0023
Brock Mfg., 11852 Western Ave., Stanton, CA 90680, (714) 898-4366
Fox Light Inc. (formerly Airplane Factory), 8300 Dayton Rd., Fairborn OH 45324, (513) 864-5607)
Feather Lite, PO Box 781, Boonville, CA 95415, (707) 895-2718
Great American, 1180 Pike Ln. #5, Oceano, CA 93445, (805) 481-9054
B & T Props, 3850 Sherrod Rd ., Marriposa, CA 95338, (209) 742-6743
Sport Flight, 22267 Powell Rd., Brooksville, FL 33512, (904) 796-1874