Date: Fri, 22 Jan 1999 03:47:19 -0500 From: Glenn Murray Subject: COZY: First flight Hi Guys, Well after waiting weeks for a gap in the weather here,my test pilot finally got my bird into the air. What a feeling watching this plane through its paces.Keep building it is the most rewarding experience you will ever have!!! Now for some advice from the more experienced of you please. The engine wouldn't rev beyond 2100 rpm (0-320 E2A) ex Cherokee 140 I suspect the prop is too course.The cylinder head temps were all at 475 degs. could the two be related? Also the canopy which is forward opening was lifting an inch at the rear against the latches.Al wick might have the answer there. Everything else worked perfectly and the aircraft was extremely stable. Keep building,your efforts will be rewarded many fold Glenn Murray From: cdenk@ix.netcom.com Date: Fri, 22 Jan 1999 16:35:56 -0600 (CST) Subject: Re: COZY: First flight On 01/22/99 03:47:19 Glenn wrote: > > >The engine wouldn't rev beyond 2100 rpm (0-320 E2A) ex Cherokee 140 >I suspect the prop is too course. Cutting an inch off diameter should give you a 100 RPM increase. Is the engine healthy - good compression, mixture OK (should get roughly 20 RPM increase with a little leaning), is valve lift spec. (not worn cam lobes), spark plug color OK? Who's prop, pitch diameter, model number. Maybe someone has a similar, and can compare experience. Too early for you, but what is cruise/climb performance, RPM at various altitudes. The cylinder head temps were all at 475 >degs. >could the two be related? Maybe, lean mixture or ignition timing cause high temps in addition to poor fitting baffles, and others. >Also the canopy which is forward opening was lifting an inch at the rear >against >the latches.Al wick might have the answer there. Whose latches are you using? The Cosy Classic, like Nat's but both sides, tied together. Mine stay down! Date: Sat, 23 Jan 1999 17:36:28 -0500 From: "Marc J. Zeitlin" Subject: COZY: First Flight Glen Murray wrote (but once again, majordomo outsmarted itself and didn't deliver this [because the word "who" was the first word on the 8th line]); >Hi Guys >Many thanks for all your letters of congratulations ,and as most of your >asked the same questions here are the answers to most questions. >I'm measuring the temps using thermocouplings under the spark-plugs, >With an outside air temperature marginally above freezing, temps were:- >N01 cylinder reading constant 400 and all the rest 475 degs.I'm hoping it's >due to the course pitch prop. I've sent the prop back to the manufacturers >who have assured me that they are able to "speed it up" by shaving it. >I'm hoping that works. >I also de-glazed the bores of all cylinders and fitted new piston rings and >ground the valves in.I'm also using 100 straight Oil for the running in >period. >I'm hoping that all of theese things combined are having the effect of >putting >added strain on the engine causing the high-cyl temps and reduced engine >R.P.M. Do you agree?If not is there anything else I can try?The test pilot >said he had difficulty breaking ground with just 2100 RPM and thought it >wouldn't lift two adults as it stands. >I paid particular attention the engine baffling as the subject was well >discussed on this site as the most probable cause of high cyl-head temps. >The temps on the ground during static run reached 475 after about 10 mins >with an OAT of 1 deg Celcius.The test pilot said they never dropped below >the 475 until he was on base turning finals . >Once I've had the prop back and carried out the second test flight I'll >let you all know how we have fared. >Bye for now >Glenn From: cdenk@ix.netcom.com Date: Sat, 23 Jan 1999 19:16:25 -0600 (CST) Subject: Re: COZY: First Flight Glen Murray wrote >>using thermocouplings under the spark-plugs These are about 50 degrees higher than the bottom bayonets, but you are still high. >>"speed it up" by shaving it. Don't know if I would have jumped to this without knowing what cruise is. >>I also de-glazed the bores of all cylinders and fitted new piston rings and >>ground the valves in. For up to about 10 hours or so, the engine could run hot like yours, usually though after a couple of hours it settles down to normal. >>said he had difficulty breaking ground with just 2100 RPM At what indicated airspeed does the nose break ground with full back stick? Could be,whats you weight and balance?? How much weight on your nose wheel when you weighed it empty?? Check canard shape and incidence! and dragging brakes, you should be able to roll it around on level concrete with one hand. Tire pressure! >>I paid particular attention the engine baffling What is the gap at the top and bottom of the barrels (where wire is holding together), and is the opening flared for smooth airflow. Can you get pictures scanned, and attach to E-mail? >>The temps on the ground during static run reached 475 after about 10 mins SHOULD only ground run at high power briefly, certainly less than ONE minute. Check cylinder bores for scuffing, mainly at the top. DO you have a 1/2" high fence where the rubber baffling touches the cowl top and bottom? You should not be able to see any light through around the baffles, except where air is supposed to go. Caulk cracks and voids with red RTV. From: cdenk@ix.netcom.com Date: Sat, 23 Jan 1999 19:16:25 -0600 (CST) Subject: Re: COZY: First Flight Glen Murray wrote >>using thermocouplings under the spark-plugs These are about 50 degrees higher than the bottom bayonets, but you are still high. >>"speed it up" by shaving it. Don't know if I would have jumped to this without knowing what cruise is. >>I also de-glazed the bores of all cylinders and fitted new piston rings and >>ground the valves in. For up to about 10 hours or so, the engine could run hot like yours, usually though after a couple of hours it settles down to normal. >>said he had difficulty breaking ground with just 2100 RPM At what indicated airspeed does the nose break ground with full back stick? Could be,whats you weight and balance?? How much weight on your nose wheel when you weighed it empty?? Check canard shape and incidence! and dragging brakes, you should be able to roll it around on level concrete with one hand. Tire pressure! >>I paid particular attention the engine baffling What is the gap at the top and bottom of the barrels (where wire is holding together), and is the opening flared for smooth airflow. Can you get pictures scanned, and attach to E-mail? >>The temps on the ground during static run reached 475 after about 10 mins SHOULD only ground run at high power briefly, certainly less than ONE minute. Check cylinder bores for scuffing, mainly at the top. DO you have a 1/2" high fence where the rubber baffling touches the cowl top and bottom? You should not be able to see any light through around the baffles, except where air is supposed to go. Caulk cracks and voids with red RTV. From: cdenk@ix.netcom.com Date: Sun, 24 Jan 1999 08:18:10 -0600 (CST) Subject: Re: COZY: First flight On Gmurray wrote: > >The engine wouldn't rev beyond 2100 rpm (0-320 E2A) > Have you checked the tach for accuracy? Date: Sun, 24 Jan 1999 08:48:07 -0600 From: David Domeier Subject: Re: COZY: First flight Carl, Re " Have you checked the tach for accuracy?" The test pilot reported that he did not think the airplane would lift off with 2 people on board.....the rpm indication probably is correct and the prop needs to be reworked. Take off rpm should around 2300, IMHO. dd From: cdenk@ix.netcom.com Date: Sun, 24 Jan 1999 15:32:21 -0600 (CST) Subject: Re: COZY: First flight Gmurray said My static RPM's for the various props I have run the last year have been between 2150 and 2300 Rpm, and takeoff distance maybe ranged between 1700 and 2200 feet. Need to know more info as checks and balances as to whats happening, I wouldn't jump to any conclusions yet! 1: What is runway length & material (paved), and Altitude? If you are at Leadville, probably 6000 feet may not be enough. 2: What is the indicated airspeed that you can get the nose wheel off the ground, do you have enough runway to do that safely? A second person could easily double the distance. 3: What was the weight on the nose wheel when weighed?? Will the plane set on the nose wheel when level without any other weight onboard? 4: Check the canard crossection shape, if necessry, start from scratch with making new templates, is its surface contour/ finish smooth and free of defects? 5: Are the elevators correct shape, travel, gap to canard? 6: Who's propeller, model, pitch, diameter? What does the manufacturer say? Has he furnished to another similar plane, who, talk to him. 7: I'm not confident your engine is putting out the proper power, check mag timing, mag drop, compression, mixture - leaning at high power should give an increase in RPM. We are trying to get you flying safely as quick as possible, but need know the above to start to figure out what the issues are. From: "Nat Puffer" Subject: Re: COZY: First flight Date: Thu, 28 Jan 1999 19:24:27 -0600 Builders, The horsepower produced for takeoff is a function of engine rpm. I like to have a prop which delivers 2400 rpm full throttle static and 2700 rpm full throttle at altitude. Without looking at my 0-360 operating manual, if you are only getting 2100 rpm static, that would probably equate to about 100 hp, and you might have to go quite a distance to lift off the ground with 2 people on board. If you are only getting 2100 rpm static, you should ground your airplane until you find out what is wrong. It is either a very sick engine or a grossly mis-matched propellor. Regards, Nat ---------- > From: David Domeier > To: cdenk@ix.netcom.com > Cc: GMURRAY@compuserve.com; cozy_builders@canard.com > Subject: Re: COZY: First flight > Date: Sunday, January 24, 1999 8:48 AM > > Carl, > > Re " Have you checked the tach for accuracy?" > > The test pilot reported that he did not think the airplane would > lift off with 2 people on board.....the rpm indication probably is > correct and the prop needs to be reworked. > > Take off rpm should around 2300, IMHO. > > dd > Date: Thu, 24 Jun 1999 08:48:46 -0700 From: Eric Westland Subject: COZY: First Flight! After 7 years and five months of some of the most enjoyable work I have ever done, our Cozy Mark IV made it’s first and second flight yesterday at Arlington Municipal Airport. N325PD is built almost true to the plans. The engine is a 200 H.P. Lycoming IO-360-A1A with a C series sump to accommodate the Bendix fuel servo on the accessory case end of the engine. It’s pretty much stock as well with the exception of a Jeff Rose electronic ignition on one side. The prop was made by Props, Inc. in Newport, OR, a two blade wood prop. Inside, I added to the VFR instrumentation a Navaid wing leveler, Jeff Rose’s electronic tach, and an AV-10 engine monitor with the fuel flow function. The radios are a II Morrow SL40 comm, a Garmin transponder and a panel mounted Lowrance hand-held GPS. The angle valve Lycoming weighs 34 more pounds than the parallel valve O-360 according to the Lycoming book and N325PD weighed in at 1,175 pounds. Getting the engine to fit in the Featherlite cowls required some serious chopping of the lower cowling. Had I known at the time, I would have ordered Jeff Russell’s set of Cozy cowls already set up for this engine as it would have saved time and weight. I have been very fortunate to have some good friends that helped me along the way. One of them is a aero engineer whose business is fixing airplanes that don't quite fly as they should. He's consulted and fixed the flying qualities of many of the planes you see daily, both in the certified market as well as many of the “kitplane” companies; He set me up with Len Fox, a professional test pilot that has flown just about everything in the Navy and since retiring a few years ago, has flown on many projects – he is highly respected and the person that Vans and Stoddard Hamilton have called when they need flight test data. Len arrived Sunday evening for a week's worth of flying on a King Air project that my friend is consulting on. When the King Air developed a fuel leak and could not come to Arlington, Len asked me how soon I could be ready. I told him I thought I was, so he gave me an 8 page, single-spaced list of things to check that day and if it all checked out, we would go over it together Tuesday morning and he would conduct the first flight that afternoon. Well, it took about 12 hours to go through the list, but it all checked out and he was ready to go after lunch on Tuesday. Unfortunately, the weather wasn't. The weather in the Pacific Northwest has been pretty much constant overcast/rain since last fall. Tuesday was no exception, but by 5 PM Len thought the weather was looking acceptable and was in the run up area ready to go. However, after looking to the South one final time, he decided to wait another hour and came back which was fine with me. Sadly, after another hour the weather closed in gradually, so we decided to wait until the next day. We woke up yesterday to rain and 1,600-foot ceilings which continued until 3 PM when Len came to me to say he thought it was breaking and wanted to give it a go. The first flight test card he prepared was for a 20 minute flight to check the controls, nose gear, engine temps and pressures and landing characteristics. Max speed would not exceed 140 knots. By 3:30 PM he was in the air running through the flight test card and 20 minutes later he landed and gave me a big thumbs up as he passed me by on the way back to my hanger. There we pulled the cowlings to check everything out. Other than a very small oil leak, all was great, so we buttoned it all back up for the second flight. Included on this test card was flight up to VNE (190 knots) to test all the controls for effectiveness and flutter, slow speed to check controllability and stall speed, checking to see how it would handle in a runaway trim event. Once again he would also record all the engine functions and do a bunch of other checks related to it’s flying qualities. This flight was to last 90 minutes. By this time, a patch of blue sky opened up east of the airport, which allowed Len to climb to 9,000 feet. Being well away from local traffic this time, he would report back to me by radio as he ran through all the tests. I was thrilled to hear him tell me it performed great at VNE, was fully controllable at 55 knots and flew hands-off straight. Other than a couple of alternator field trips when he adjusted the electric pitch trim, the flight was uneventful and Len was very happy with all of it’s flying qualities. He is going to write up a report for which I can share later. For now, it’s time to get some rest and go though the plane again. It’s once again foggy and rainy and there is no relief in sight in the forecast. There are just too many folks to thank and I’ll do that personally to each. However, I do need to thank many of you on these lists that have provided so many tips, answers and suggestions over the years. You have saved me much time/money and aided to the quality of our plane. Much of this still has not sank in. When I think about it, it’s all really quite amazing. You order plans (which are excellent), you get a bunch of raw materials and start making parts. One year you make a wing and the next you make another. Then you put them all together, wipe micro all over the parts and start sanding. One day you step back and it looks like a plane, but will it fly (or if it does, will it fly straight)? Not a day went by that I did not wonder that. After all, I'm not an engineer and I've never built a plane before. When it actually happens and the answer is a firm yes, to me it’s most amazing. What a deal! Eric Westland Mukilteo, Washington From ???@??? Sat Jul 03 17:34:47 1999 Return-Path: owner-cozy_builders@betaweb.com Received: from twc2.betaweb.com (majordomo@betaweb.com [206.43.209.18]) by acestes-fe0.ultra.net (8.8.8/ult/n20340/mtc.v2) with ESMTP id JAA21108 for ; Mon, 28 Jun 1999 09:47:35 -0400 (EDT) Received: (from majordomo@localhost) by twc2.betaweb.com (8.8.5/8.8.5) id IAA18318 for cozy_builders-list; Mon, 28 Jun 1999 08:57:12 -0400 X-Authentication-Warning: twc2.betaweb.com: majordomo set sender to owner-cozy_builders@betaweb.com using -f Received: from post.larc.nasa.gov (post.larc.nasa.gov [128.155.4.45]) by twc2.betaweb.com (8.8.5/8.8.5) with ESMTP id IAA18313; Mon, 28 Jun 1999 08:57:07 -0400 Received: from htgpc.larc.nasa.gov (htgpc.larc.nasa.gov [128.155.44.142]) by post.larc.nasa.gov (8.8.8.1/pohub4.3) with SMTP id IAA02317; Mon, 28 Jun 1999 08:56:50 -0400 (EDT) Message-Id: <3.0.32.19990628085852.012074d0@larc.nasa.gov> X-Sender: p.w.krasa@larc.nasa.gov X-Mailer: Windows Eudora Pro Version 3.0 (32) Date: Mon, 28 Jun 1999 08:58:53 -0400 To: canard-aviators@canard.com, cozy_builders@canard.com From: Paul Krasa Subject: COZY: First Flight Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-cozy_builders@betaweb.com Precedence: bulk Reply-To: Paul Krasa X-UIDL: 119e3a2fa38f8e8ea4e9a5944e8a4b93 After four years of work Long Ez 214LP took to the air the first time on Sat. 6/26. The flight was uneventful and short. The handling is great, and I really had to throttle back to keep the speed below 140. I have two problems to fix before the next flight. My landing brake would not stayed deployed, and the CHTs where in the red during climb out. To solve these I will increase the strength of the springs on the landing brake, and set up the manometer and tubing to find out what is going on in the cowl. Paul Long EZ 214LP p.s. God I am glad the first flight is done. What a relief! From: cdenk@ix.netcom.com Date: Mon, 28 Jun 1999 15:22:22 -0500 (CDT) Subject: Re: COZY: First Flight Landing brake won't stay extended: The linkage is supposed to go "Past Center" slightly, check the dimensions carefully, I don't think the fix is stronger springs. Cylinder Temps: several possibilities: Timing advanced - check, lean mixture - should get increase RPM before drop when leaning, Fresh ring on pistons - give a few hours to break in, and other issues. Date: Mon, 28 Jun 1999 21:43:37 -0500 From: David Domeier Subject: Re: COZY: First Flight Paul, re "My landing brake would not stayed deployed," Could be you were a bit high on speed. My LEZ brake used to blow shut at about 90KIAS....I wouldn't do anything with it until you fly again. They land just fine without it. Congrats on the first flight. Makes it all worth it.... dd Date: Sun, 27 Jun 1999 07:49:15 -0400 From: "L. Wayne Hicks" Subject: Re: COZY: First Flight! Congrats Eric! Looks like the perserverence paid off. Some questions if you don't mind: 1. Where did you get your engine? (Trade-a-plane, rebuilt shop, etc?) 2. If you had the engine rebuilt by a shop, could you comment on who rebuilt it and if you were happy with the experience? 3. Sounds like you had a thorough pre-flight inspection checklist. Would it be possible to get a copy of that checklist? 4. Would it be possible to get copies of the test cards too? Again, congratulations! Wayne Hicks Cozy IV #678 Chapter 13 http://www.geocities.com/yosemite/falls/2027 Date: Sun, 27 Jun 1999 09:17:02 -0700 From: Eric Westland Subject: Re: COZY: First Flight! "L. Wayne Hicks" wrote: > > Congrats Eric! Looks like the perserverence paid off. > > Some questions if you don't mind: Sure! > > 1. Where did you get your engine? (Trade-a-plane, rebuilt shop, etc?) I looked everywhere - I mean everywhere. 360 cubic inch Lycomings are really tough to find. My goal was to find one that had some time left on it before overhaul so I would not have to test the airframe and break in new cylinders at the same time. Many have done this successfully of course and since I have found mine, many have reported Bart up at Powersport(?) in B.C. as an excellent choice for a rebuilt engine. He's doesn't do it for free, but then again, I don't think I'll end up doing it my way for any less - as a matter of fact it could end up costing me more once I split the case. We'll see. I found Trade-A-Plane almost a total waste of time and money. The market was just too hot while I was looking. I also joined the insurance company salvage bid lists, but never found a plane/engine that I could even bid on. The internet at the time gave me the most promising leads, searching various aviation for sale sections. I joined the RV and Mooney e-mail lists amongst others to learn where others were getting theirs. While reading the Mooney list, I discovered that occasionally someone would be converting their perfectly good Mooney's IO-360 to a bigger engine to go faster. That lead me to some private parties and some companies that do conversions - Rocket Engineering in Spokane, WA and Mod Works in Florida. I ended up getting a good IO-360 from Mod Works. Since then they have started advertising in Sport Aviation, so the "secret" may be out. You must continually call places back. If you leave your name and number for when an engine becomes available, they will probably sell it to the next person that happens to call. You really, really need to educate yourself on engines if you buy a used one. The word _overhaul_ is probably the most loosely defined word in aviation. You need to know what someone is selling you. Find all the AD's, get a copy of the logs, call the mechanics, determine how often it's been flown annually, search the internet for accidents by tail number. Any of the above ways can work and there are probably others. > > 2. If you had the engine rebuilt by a shop, could you comment on who > rebuilt it and if you were happy with the experience? Mine has 2100 hours total time, but the compression is still great, so I hope to get the hours flown off and then finish overhauling what I already have not done. All the AD's have been complied with including the one for oil pump gears. The ignition system has been done (new mag stuff and electronic ignition), new mechanical fuel pump, vacuum pump, alternator and starter. Don Rivera did the OH on all the Bendix fuel injection parts - he has been great to work with. So that basically leaves the crank, case and cylinders and I'm not exactly sure where I'll have that done yet. > > 3. Sounds like you had a thorough pre-flight inspection checklist. > Would it be possible to get a copy of that checklist? > > 4. Would it be possible to get copies of the test cards too? > Many have asked and I'll be happy to share them both provided that my test pilot gives his permission. I should see him again in the next couple of weeks. These are items he generates as part of his business and I'm not sure if they are mine to share. I'll gladly ask though. -eric Date: Mon, 28 Jun 1999 01:09:58 -0600 From: rlacour@trib.com Subject: Re: COZY: First Flight! >Well another first flight!!! On June 26 1999 a saturday I flew my cozy mkIV after five years of intense builder,lost a year to the winters of Wyoming. The flight was uneventful,except that I flew about 12:30 in the am,after a small airshow was finished at our airport.Flying at this time made the air very angry and it and the thermos proceeded to give me an interesting ride. I performed about 2 hi speed taxi tests up and down the runway to get a feel of the a/c and to check out any shimming that might be there.I found some shimmy,but at about 65k the shimmy went away and the a/c rode straight.When you taxi test make sure you donot skip the hi speed taxi,this will give you a feel for the whole plane.After 2 taxi test I was ready for the " big one".I taxied out to the centerline,applied power and was off,at about 80k I lifted the nose and started to fly,after the customary bob I established a ascent of what I thought was 110k and started downwind,having previosly flown a C172 for bi-annual it was interesting to see a 140mph at the start of my downwind.Before I could plan anything I was in position to start my landing.I trimmed out the plane for 85k(that goodness for the Strong elevator trim)proceeded to get back on the centerline,this thing moves fast,lower the belly board and set up the landing.When my spotter on the ground told men I was about 10 feet in the air I started a gentle flare and Bingo I was on the ground,I lifted the nose for better braking and proceeded to the hangar,where the first one to greet me at the plane was my DOG(People are scarce here in Wyoming). My next flight should be monday the 29th of june,will write a more complete report then. Rick LaCourse Flying Cozy MKIV #237 N8191VICTOR Date: Thu, 01 Jul 1999 08:26:41 -0400 From: Paul Krasa Subject: COZY: CHT and Landing Brake Problems solved. Well, I made the second flight yesterday. A solid .7 hours. The day was overcast, and I went up to 2000 ft. and flew patterns above the runway at 120-130 kts. FUN, FUN, Fun! The airplane handles nicely, and boy is it responsive even at these low speeds. I had no problem slowing the airplane down from this speed or lossing altitude. I flew a standard pattern for landing, and I trimmed for 90kts on final and touched down at 75kts. Not a bad landing for a second attempt. I did end up about 1500ft down the runway, but with a 6000 ft. runway, no big deal. I never touched the brakes letting the airplane role out. Thanks to all that provided me with the information on the speed brake. After adjusting the geometery, it works as advertised. Thanks again. As for the CHT being high, I checked the vernitherm valve and it was bad. Put a new one in and the CHT is now 420 F on climbout with a washer type thermocouple and less 350-380 in cruise. Oil temprature stays around 200 deg. Paul :') Long EZ 214LP Hobbs time including high speed taxi: 7.0 33hrs of testing to go. Date: Tue, 10 Aug 1999 11:39:13 -0500 (CDT) From: Steven Eberhart Subject: COZY: Test Flight Plan For those of you getting close to test flying, you might like to take a look at http://www.evansville.net/~boeing/project_viking Chapter 11 Test Plan. THis is a comprehensive flight test plan put together by Rick Junkin, a professional test pilot for McDonnel Douglas/Boeing. THe plan is tailored for the KR-2S but most everything, with the exception of the performance numbers, would apply to any Sport Aviation aircraft test flight program. Steve Eberhart mailto:newtech@newtech.com THE WING FLIES! - http://www.newtech.com/nlf for info on the new, flight tested, KRnet airfoils. Good job KRnet, you can be proud of your contribution to Sport Aviation. One test is worth a thousand expert opinions but a thousand opinions are easier to get. --plagiarized from an unknown author All information, in any of my aircraft related correspondence, is strictly food for thought requiring additional, qualified, engineering analysis. From: FLYCOZY@aol.com Date: Thu, 28 Oct 1999 20:55:48 EDT Subject: COZY: Re. inspection / first flight Fellow builders After 20 months of intense building there is really and end. Yesterday, The F.A.A. inspector out of Des Moines, Iowa came to my hangar to do the inspection on Cozy Mark IV N 92VT . The inspection went very smoothly with nothing to do but attach the data plate in the appropriate place. " Under the wing strake below the sump blister is where he wanted it". He said the aircraft was the most well done that he has ever inspected. He was very impressed with the design and really liked the visability from the cockpit. After I showed him all the little creature featured that we all like , He asked me if after I had the flight time flown off if he could have a ride!!! he issued me a airworthiness certificate and a temporary builders certificate. Today, wind 5 knots clear skies. N 92VT flew for the first time. And yes it's just as much fun as my first flight in my cozy three 12 years ago. The mark IV weight in at 1258 lbs. Cg is 108.16. I think this is about in the ball park as far as weights even though some would disagree! Doug Kosters now weighs right at 1300 lbs with a IO- 360, Tim Merills 1320 with a 0-320 and constant speed propspeed prop and full IFR panel. And next year were bringing scales to Osh Gosh to see what some other airplanes really weight. My mark IV is completely per plans as far as dimensions and length . I consider major modifications to airfoils and fuselage major modifications. N 92 VT is stock Engine is 0-360 180 hp. A1A, Ellison Throttle body, Steve Wright nose lift, Vision micro system engine analizer a King 76A transponder and encoder King KX125 nav/com, Garmin GX65 GPS/Com. Garmin audio panel with marker becons and built in intercom. I installed a different heat system than the standard heat muff. I don't care what anybody says Heat muffs are ok for carberators but it's a long way to my toes and the just don't cut it in Iowa . So I installed a second oil cooler in the nose on the passenger side took a blower fan out of a Honda CRX junk car. " Home builders are such scroungers" and built a squirrel cage fan out of a block of foam to push the air through the cooler and just heat the cabin air . There is another oil cooler mounted on the engine mount that cools engine oil. I ran the oil lines throught the center duct which the plans say to use for hot air. I ran 3/8 aluminum lines exiting the duct underneth the co-pilots thigh support and into bulkhead fitttings where they go through the instrument panel along the floor to a ball valve on the floor on the passengers side to the cooler. IT WORKS GREAT!!! I GOT HEAT. and lots of it. To regulate it just adjust the oil flow to the cooler.Leave the fan on high. So far I can feel the heat coming out from underneath the instrament panel I'll keep ya posted. Oh, The airplane flies great, I DON"T have one thing I have to adjust or change. Oil temps were 198 with a 0 time engine and CHT's were right at 380 I flew the airplane for an hour first flight. varying the rpms between 2100 and full throttle. I built the baffling and lower cowl baffles exactlly per plans!! Nats right, the ailerons don't have to be changed or made bigger the roll rate is much faster in the 4 over the 3 place. The canard has been shortened the 3in. he recomended. Ground handling is supurb with the big brakes. I even got the chance to try out my own rudder pedal design. I really like them. Nat , Thank you!! .... You deserve alot more credit and respect than you sometimes get for all you've done in designing such a wonderfull airplane . I guess sometimes when I see some of the changes that some people are thinking about and the things some people worry about are really foolish. In fact some times I'm laughing so hard I can't even get up off the floor to respond. These are also the builders that will probably never finish ther project because their to busy changing things. Then I think back and remember I had those same fears and dumb ideas and I take a lesson in humility. I was glad I asked alot of questions. But I have to admit most of the answers are in the plans if ya read further and study the drawings.Usually major mod changes cost you 3 ways time , money and weight. sometimes safety!! When I built my cozy 3 I usually waited till somebody more experienced than I did a change then waited a few months to test it , then decided if it was worth it for me. That's still my policy. Some facts, when ya get all the glass work done your half done. Just keep going. Ask questions no matter how dumb ya thing they are! It's all worth it in the end. I need a beer!! Dennis Oelmann