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Marc Zeitlin

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Posts posted by Marc Zeitlin

  1. Originally posted by LargePrime

    That list is in the public domain and anyone can do whatever they want with it.

     

    You are incorrect. The COZY mailing list is NOT open to the public. Merely because something is posted to a mailing list does not automatically put it in the public domain, your opinion notwithstanding. If you'd like to reference some legal opinion refuting this, please do.

     

    Originally posted by LargePrime

    I guess I can just hope HE never finds my email address, or I'll be a victim of bullying too!

     

    Since I'm one of the four admins here, I have long since found your email address. Since I've never contacted you in any way other than our interactions on this forum, how have I victimized or bullied you?

  2. Originally posted by John Slade

    .....If I post somewhere - flyrotary, cozylist, my web-site, aeroelectric list, where-ever, I'm posting information or comment for public consumption. Period.

    And I feel the same way, but not everyone does. Since permission was not asked, the safe thing to do is not post it until permission IS granted, and not post it if it's not granted.

     

     

    Originally posted by John Slade

    How do other members feel about comments on this list being reposted on other lists? Marc? Is it ok the other way around? If so, why the difference?

    Nope. It's not OK to take anything off this list and post it anywhere else, without the writer's permission, either. Goes both ways. It's just common courtesy.

     

    Originally posted by LargePrime

    Anyone should post whatever they want here . Cross pollination is good, even great.

    I agree - cross pollination and information sharing is great. __IF__ the original writer agrees to it.

     

    Originally posted by LargePrime

    The posted content is public domain and let no one tell you different.

    You know, I'm sure I could go online, and for anywhere between $0 and $20, find out who you are, where you live, your bank account balances, whether you're married or divorced, what kind of car you drive, and how you feel about airplanes. I could then post that information here, or anywhere else, since it was "public domain", and you'd be OK with that, right? No, I thought not, and I would not do such a thing, because it would upset you, and rightly so.

     

    All I ask for is the courtesy of asking the original writer for permission to post their writing somewhere other than they originally put it. I really don't think that's an onerous request.

     

    Originally posted by Joe Patterson

    I surely meant to do nothing wrong.................

    Of that I've no doubt.

     

    Originally posted by Joe Patterson

    Whatever penalty you asses, I will submit to.

    The wife flogging thing sounded, ummmm, interesting, if you take some pictures.......

  3. Originally posted by Joe Patterson

    I agree whole heartedly

     

    Joe, it is extremely inappropriate to take a posting from one mailing list/forum and quote it, essentially in it's entirety, in another mailing list/forum. This has been discussed/requested here previously - must have been before you joined.

     

    If the writer of what you quoted had wanted the statement to appear here, s/he'd have put it here. If you want to reference the statement and paraphrase, that's a different story, but please, do NOT post messages from other mailing lists here without the original writer's permission, and at least attribution.

     

    Thanks.

  4. Originally posted by No4

    .... But in this instance I believe 300 true is possible, and I disagree that the plane will suddenly take a nosedive.

     

    If you read my statement carefully, I said that the designer of the airfoil BELIEVES that the critical Mach # for that airfoil will be around 0.5, or 346 mph at 25K ft. It could be higher, it could be lower. It's doubtful that it would be as low as 300 mph, and I never said that there's a problem at 300 mph TAS.

     

    Originally posted by No4

    Marc in fact quotes Vne ( I would call it Vmo, max operating) to be 300 True.

    No, what I said was that for the sake of having some safety margin, Richard Riley __recommended__ that 300 TAS be Vne or Vmo, whichever you'd like to call it. Berkut claims a top TAS of about 300 mph - no Berkut will INDICATE 300 mph - more likely about 260 - 275 mph, but that's a guess. I do not know exactly what airfoil the Berkut uses, either for the canard or the main wing - I do know that they do NOT use the same airfoil for the main wing as the L.E. and COZY.

     

    Originally posted by No4

    ... Have any Lancair's "Shock Stalled"? I doubt it.

    The issue here is with the specific Roncz airfoil used for the canard of the COZY aircraft. Please list all the other certified/homebuilts that use this airfoil for flight over 345 mph before making such cavalier statements about safety issues......

     

    Jim, others, See:

     

    http://142.26.194.131/aerodynamics1/High-Speed/Page2c.html

     

    for more information on this phenomena. I thank Richard Riley for pointing me to this reference.

     

    With respect to other questions, sweep in the canard, or a different airfoil MIGHT ameliorate the situation to some extent, but the factors that make this a good airfoil for a canard aircraft make it bad for "Mach stall", and the factors that give other airfoils a better "Mach stall" number make them poor performers as a canard airfoil in our type aircraft. Everything's a tradeoff. New airfoil or sweep - it's not even close to being a COZY anymore, and you better be an aerodynamicist.....

     

    With respect to Jim Price's L.E. - the fact that he went to 35.5K ft. with a 135 HP engine makes it even more amazing :-). Realize, of course, that he was not at gross weight, and that service ceilings are determined (at least in certificated aircraft) at maximum gross. I don't know if the AeroCad/COZY service ceilings were determined at gross weight, but that's how they SHOULD be quoted.

     

    To Evan's question, a normally aspirated COZY MKIV with a fixed pitch prop won't get close to 200 mph, much less 346 mph TAS at 25K ft. Some are proposing substantial power increases by turbocharging and/or substantially larger engines, and using CS props, and then the answer seems to be that 300 mph at that altitude should be achievable.

     

    Hence the warning.

  5. The question was asked "how high can a COZY go?". Jim Price has taken a normally aspirated 160 HP Long Eze to over 35,500 ft., and holds the altitude record for that weight class of single engine piston aircraft.

     

    Vance Atkinson has taken his 160 HP COZY III to 23K ft and performed a stall series there. His TAS was 152 KT at full throttle.

     

    Aerocad claims a Service Ceiling (100 fpm climb rate) of 25K ft. with a 200 HP engine. I have some vague recollection of Nat stating 26K ft. service ceiling for the COZY MKIV, although I can't find a reference.

     

    With respect to top speeds, the Roncz canard is suspected (by John Roncz, the designer) of having a critical Mach # of about 0.5. At that point, the canard will Mach stall, and the plane will become an uncontrollable lawn dart (per discussions with Richard Riley - one of the former principals in Berkut Aviation, the fastest homebuilt canard).

     

    0.5 Mach is 380 mph TAS at sea level (we don't ever have to worry about getting there). However, at the altitudes that some people are talking about, say 25K ft, 0.5 Mach is 346 mph. Notwithstanding flutter considerations (which a simple web search, left to the reader as an exercise, will show is dependent both on TAS and IAS), this critical Mach # is one limit that you do not want to get near. Since 200 mph IAS is ~300 TAS at 25K ft., that's not far away from 346 mph - a short dive to change altitude, or a distraction and small stick bump could easily lead to a large speed change in a short period of time in these slippery aircraft.

     

    Mach stall is unrecoverable, unlike a short stint above Vne, or even a short stint with flutter. In either of the other two cases, throttle reduction and/or stick pressure will reduce speed and most likely eliminate the problem. Once Mach stall occurs, the nose drops, the speed builds, the Mach stall gets worse, and as RR has said, you tie the low altitude record while pointed straight down.

     

    RR believes that no aircraft using the Roncz canard should use a number higher than 300 mph TAS for Vne. Since no COZY's now exist that can reach this #, the 220 mph IAS Vne has proven acceptable - if people put substantially more speed capability into their aircraft, such as Greg Richter, or some of the posters here, Mach stall will become a large factor in their considerations.

     

    Just thought this might help some people in evaluating their options.

  6. Originally posted by cncdoc

    If it is from Nat's specs, are those based on tested flying product or extrapolation derived from other known values of similar craft.

     

    The Vne and Va number I quoted were from the COZY MKIV manual. I will not presume to state where Nat got those #'s from, but the Va (which is what we're interested in here), seems to match up with the 3.8 G limit for Normal Category aircraft, as verified by the performance numbers of my plane in particular, and the published performance data from Nat's plane.

     

    Originally posted by Jim Sower

    180 mph (156 (use 155)) kts is the highest speed at which you cannot pull the wings off the airplane. .... The 180 figure ("corner" of the Vn diagram)

     

    The only issue I have is this 180 mph number, and it's relation to the 6 G figure. I have no clue where this 6 G limit came from - I don't ever remember seeing it in the owner's manual, or anywhere else, for that matter. If you've got some reference for that, I'd be very interested in seeing it.

     

    Personally, as a LIMIT LOAD #, I'd use the Normal Category limit of 3.8 G, which is what Nat seems to be recommending by his claim of 140 mph as the Va.

  7. Originally posted by Jim Sower

    Agreed. I would hazard a guess that FAA requires that spam cans withstand 4G to be certified as normal category, and he just went with that.

     

    Normal is 3.8 G, Utility is 4.4 G.

     

    Originally posted by Jim Sower

    Am I safe in assuming that Nat's Va is pretty much what I'm referring to as "maneuvering speed"?

     

    Yes.

     

    Originally posted by Jim Sower

    In future interaction with you, my friend, I will endeavor to be less assertive and righteous......

    And I to be more accurate in my statements.

     

    Originally posted by Jim Sower

    Why do we do this to ourselves?

    The lack of face to face interaction makes it easy to misunderstand and get bent.

     

    Originally posted by Jim Sower

    but don't think for a minute you can slip some bullshit by me!:D

     

    My raison d'etre is gone.......

  8. I've deleted all the stuff we agree on - let's continue:

     

    Originally posted by Jim Sower

    NO!! You can pull whatever G loading the pitch authority AND AIRSPEED will allow. ........ Ever look at a Vn diagram? I wouldn't be surprised if they don't make them for Cessnas, but the heavy iron needs them and pilots need to know them well.

     

    I am familiar with Vn diagrams, and they are available for GA aircraft. After a night of pondering, I agree that you are absolutely correct here - up to Va, you need airspeed to achieve a certain G loading - I missed that in my previous analysis.

     

    Originally posted by Jim Sower

    Incidentally, "maneuvering speed" is the lowest speed at which it is possible to load the airplane to it's G limit (6 for the Cozy).

     

    I'm not sure where that 6G comes from. I did some calculations from the stall speed and wing area on my plane, and here's what I come up with:

     

    Wing area (including canard): 110 ft^2

    Max average Cl: ~1.4

    Weight for calcs: 1800 lb.

     

    These come from a stall speed of about 72 mph at that weight. Given that (at Sea Level), the Vn curve below Va for the COZY looks like:

     

    0 degree bank - stall speed ~72 mph - 1 G

    60 degree bank - stall speed ~96 mph - 2 G

    70.5 degree bank - stall speed ~126 mph - 3 G

    74.7 degree bank - stall speed ~142 mph - 3.8 G

    80.4 degree bank - stall speed ~180 mph - 6 G

     

    Since the Va of the COZY is about 140 mph (IIRC), I've got to assume that Nat picked the 3.8 G from the normal category of certification to get his Va. If Va was 180 mph, then 6 G would be the limit.

     

    Anyway, given this info, increasing speed up to 140 mph will, as you said, give you the tightest turning radius - from ~125 m radius at 2 G to about 110 m at 140 mph and 3.8G.

     

    Originally posted by Jim Sower

    But if you would pull to buffet, you'd get a 110 m radius.

     

    Bingo - pretty good guess :-) - or did you calculate that?

     

    Now, at any speed OVER 140 mph, your radius will start getting larger again, since you're not allowed to pull more G's. So, for the conditions postulated (SL, any amount of power needed), Va will give the tightest radius turn.

     

    Of course, the COZY can't maintain 140 mph banked at 74.7 degrees in level flight even at SL, so it'll never get this good :-).

     

    The book I mentioned previously, John T. Lowry's "Performance of Light Aircraft", has some excellent explanations and graphs of maneuvering performance of GA aircraft taking power and altitude into consideration, and has some good examples of how to get yourself into trouble in a climbing narrow canyon.....

     

    Originally posted by Jim Sower

    I think that, once again, we find ourselves in Violent Agreement... :D :D

     

    Better that than violent disagreement :-).

  9. Originally posted by Jim Sower

    As a matter of fact, for max rate turns, G rules. Consider: your level turn radius is a function of speed and how many G's you're pulling (increases with speed, decreases with G).

     

    This much is true.

     

    Originally posted by Jim Sower

    The number of G's you can pull is a function of the square of speed. So if you double your speed at a given amount of G's you double your turn radius, but by doubling your speed you've increased the G's you can pull by a factor of 4, so if you pull all those G's, you reduce your turn radius very substantially.

     

    I don't know what you're remembering here, but it isn't your physics or flight dynamics. The radius of a level turn is:

     

    R=V^2/a

     

    Where "V" is the velocity and "a" is the acceleration. Doubling your speed will quadruple your radius, and doubling your "G" loading (acceleration) will halve your radius. You had that backwards.

     

    Originally posted by Jim Sower

    At some point (maneuvering speed) you've reached the point at which you can pull all the G's you're allowed to and that's your minimum turn radius. Sounds counter intuitive, but it's so.

     

    Sorry, but it is NOT so. Assuming you have enough power to maintain level flight, your minumum radius turn (level), as shown by the equation above, will occur at the MINIMUM speed with the maximum acceleration. I guarantee you that in a canard aircraft (or any aircraft, for that matter, that you're willing to fly at stall speed), flying at the maximum bank angle, stalled, with the stick all the way back, will get you the minimum turn radius. See Page 260 - 264 of "Performance of Light Aircraft" by John T. Lowry for graphs of the turn radii of a Cessna 172. It is obvious from looking at these graphs that flying right at stall at bank angles of 60 degrees or above AT THE MINIMUM POSSIBLE SPEED) will get you the minimum radii. He discusses the power needs as well.

     

    Originally posted by Jim Sower

    Again, we're talking level turn, and you have to pull to buffet at whatever speed you're at. If a Cozy will juuuuust pull 4 G's at, say, 130 kts, and will juuuuust pull 6 G's at 160 kts, and you're at 130 and I'm at 160, I'll turn inside you every time.

     

    This makes no sense. AOA determines G loading. Instantaneously, you can pull whatever G loading the elevator authority will allow, and it will last for however long the power available will let it (or else you'll start down). If you can pull 6 G's at 160 Kt, you can do it at 130 Kt, and the slower speed will have a smaller radius. Instantaneous G loading is not dependent upon speed - I can do a 60 degree, 2 G turn at any speed above 85 mph (canard stall) in my plane. I can't MAINTAIN it for very long at anything over 100 mph or so, but I don't need to to do a 180.

     

    At any rate, if it takes 2 seconds for me to roll to 60 degrees, and I maintain that at 100 mph, I've got about a 125 m radius turn. Having practiced these many times, I can tell you that it looks like I'm spinning on the inner winglet.

  10. Originally posted by Jack Kretmar

    Is this those new noise reduction earphones we hear about. If so, that's interesting because they would be great for the Cozy (even though they are very pricy). Is this the case, Marc?

     

    Yes. When I was at Bose, I worked on the Bose X noise canceling headsets for pilots, as well as the first generation of noise canceling headsets for the mass market (they're now selling 2nd generation mass market headsets). Noise reduction headsets (called ANR, for "Active Noise Reduction") have been around since Bose invented them about 18 years ago, but only recently (5-10 years) has the price on many of them come down far enough for them to become very popular.

     

    I have a pair of Bose ANR headsets, a pair of Lightspeed ANR headsets, and a couple of Peltor passive headsets. The Bose and Lightspeed are great - I won't wear passive headsets anymore - the Peltors are only used for the rare times there are people in the rear seats. The Bose X were the best headsets when they came out in 1999 - I don't know if that's still the case, but they're certainly still the most expensive :-). They are VERY good in the COZY - any ANR headset is better in any plane than any passive headset.

     

    I'm no engineer, but I suspect they work by "reading" the noise signal and then instantly generating a reverse amplitude "mirror" signal to cancel out the noise. Do I have that right?

     

    Pretty good guess, for not an engineer :-). There's a tiny microphone INSIDE the earcup, as close to your ear as they can get it. It picks up all the sound that ISN'T coming through the wires, and the circuit board inside the earcup generates the same noise, but 180 degrees out of phase, so it substantially reduces the incoming noise. It doesn't actually cancel it, because the microphone would have to be inside your ear to do that (which would be uncomfortable), and because the technology only works at the lower frequencies - generally there's no effect on anything above 300-400 Hz.

     

    The Lightspeed Engineering website has an excellent tutorial on ANR headsets. See:

     

    http://www.anrheadsets.com/

  11. Originally posted by LargePrime

    I think it's pretty smart to get many opinions, and pretty stupid to stand on a short list of opinions.

     

    Agreed.

     

    Originally posted by LargePrime

    Is there a limit on the asking?

     

    Not at all. It's just that he's more likely to get the information he's looking for if he asks a somewhat more specific question, that's all. That, and the fact that there are few people on this forum that CAN answer his questions, other than those that have already.

     

    No limit - just trying to maximize the information presented.

  12. Originally posted by John Slade

    Agreed, Marc.

    This is not the place for "shut up and build - you're stupid to even ask" slams. That's over on the other list.

     

    What, so you don't want any insulting behavior between members here, but it's OK to insult other "lists"? I assume you're still referring to the canard-aviators list, which had the characteristics you posit a couple of years ago, but since you're not on it, how would you know what it's like now? In fact, for the past 9 months or so, just about everything and anything has been discussed, since a new moderator came on board. You're way out of date.

     

    Originally posted by John Slade

    So ---- personally, I'd like to hear from anyone who has ANY experience of aerobatics in a canard.

     

    You've heard from Jim Sower, your hangar mate, me (in Ken Miller's back seat) - what else are you looking to hear about? Simple, positive G aerobatics are clearly doable, but the canard aircraft roll slowly, pick up speed too fast, and are generally not optimized for these activities. Is there something we've missed in this discussion? Ask a question about something in particular.......

  13. Originally posted by Hank Stauffenberg

    Here is the FAR Section I based my statement of a requirement for a fuel cut-off:

     

    Sec. 23.995 ........

     

    What YEE SAY?

     

    I say that (directly from the FAR's):

     

    Part 23: Airworthiness standards: Normal, utility, acrobatic, and commuter category airplanes

     

    Since Amateur Built Eperimental aircraft are not certified in any of these categories, Part 23 clearly does NOT apply to our aircraft.

     

    Of course, safety would dictate that most of the requirements in this section are probably good ideas, and might be intelligent to use, but they DON'T apply to Amateur Built Experimental aircraft, and the FAA inspector/DAR CANNOT fail you merely for not complying with part 23.

     

    I don't know what that implies for who owes who $$$, but those are the facts.

  14. I guess I was unclear on my question. I fly in the USA, not in Denmark. The regulations that Mike and I (and anyone else in the USA) fly in are not the same ones that are used in Denmark (even if Denmark has borrowed some from the FAR's).

     

    I was looking for:

     

    a) an indication as to whether Hank believes that a fuel shutoff valve is/is not required, and

     

    b) if he believes it IS required, whether he (or anyone else that believes it's required to pass the FAA inspection) can point me to a regulation (USA only) that states what equipment is required.

     

    We're only talking fuel system parts here - not instruments, etc.

     

    Thanks.

     

    P.S. - I now see that Hank has started another thread, so I'll move this discussion over there.

  15. Originally posted by Hank Stauffenberg

    ....... Largeprime is correct in the requirement for a manual fuel cut-off on the fuel line.

     

    I'm not sure I understand - are you claiming that there __IS__ a requirement for a fuel cutoff, or that there isn't?

     

    Can you point me to a FAR, AC, or other FAA document that is clear on this subject one way or the other?

     

    Thanks.

  16. Originally posted by mlefebvre

    Interesting... Why can't you not fly inverted in a LEZ/VEZ/Cozy?

     

    Couple of reasons. The airfoil of the canard has a LOT of camber, and will not be able to generate the lift necessary, which is coupled to Mike's statement about not having enough elevator (although if you built in enough elevator travel, you'd probably stall the canard at almost any speed - it would be interesting [via CFD analysis] to see what range of speeds could be maintained inverted). I wonder if anyone has done that analysis......

     

    Second, the fuel/oil systems are not designed/built for inverted flight. This might be remedied, but if the aerodynamics don't support it, there's no reason to build an inverted capable engine.

  17. Originally posted by dust

    The berkuit guy put on quite a show, oh wait a second he died, well ok build an acrobatic plane,the cozy is NOT an acrobatic plane

     

    While you are correct that the canard family of aircraft is not considered "aerobatic", this isn't a good example to use of why.

     

    Rick Fessenden was pulling over 9 G's at low altitude and blacked out, causing a roll and the crash. It was NOT a function of the airplane doing something - it was G-LOC. Could have happened in any plane pulling 9 G's. Actually, that would be a good example of how well built these planes are, that they can withstand 9 G's on a regular basis - more than the pilot, apparently.

     

    At any rate, as John pointed out, any positive G maneuver is possible in the L.E./V.E./COZY aircraft. I've sat in the back of Ken Miller's L.E. while he did a 1 G roll, and if my eyes were closed, I couldn't have told that we were upside down. Loops, as John says, are NOT trivial due to the ease with which Vne can be exceeded.

     

    So, the answer is yes, simple aerobatics are possible, and as long as the G loading is kept relatively low, and always positive, a TRAINED pilot should be safe. No negative G's, no inverted flight, no whip/hammerhead/etc. stalls.

     

    I'm not trained, and I don't do aerobatics in my plane.

  18. Originally posted by Jim Sower

    There are no flying Cozys with retractable main mounts.

     

    There's at least one. Marv Schuh's COZY III had 700 hours on it in 1995, and at some point he retrofitted the Infinity gear. There's a picture of his plane on the Infinity web site. Jim Marshall's MKIV has the Infinity gear as well, but I don't know if that plane has flown yet - I couldn't find an announcement in the newsletters.

  19. Originally posted by NativeSpirit

    What is the height of the fuselage,Cozy Mark IV .........Will it roll out of my garage, if door is only 6'11"????

     

    While the winglets are about 7 1/2 feet tall, as LP says, the wings come off. You do want to make sure that you have the height available inside the garage, though, so that you can mount at least one wing/winglet at a time and work on it.

     

    The fuselage on gear is about 5 ft tall or so (not 4 ft.) so that won't be a problem either. As you surmise, the width __is__ an issue. If you have doublewide doors, you're fine. If you have single doors, getting in and out after you put the strakes on is a pain. If the diagonal distance is more than about 11.5 ft., it's doable with a substantial amount of finagling and twisting - if not, you'll have to tear the garage apart, or build somewhere else. You need to bring it out and back in twice to flip it over, and then out one more time, so the "tearing apart" must be repeatable.

     

    Originally posted by NativeSpirit Also..........I would love to visit someone with a Cozy project, I would also love a ride in one.

     

    There are at least two builders and one flying COZY MKIV in New Mexico. AFAIK, none of them hang out on this list. If you're interested in contacting them, drop me an email and I'll put you in touch.

  20. Originally posted by LargePrime

    It is MUCH better than any sort of Gull Wing. It might not look as sexy, but it is way easier to pack, get in, and out of.

     

    While there may be some advantages to the canopy (and I LOVE the visibility), just about the only thing I _don't_ like about my plane is how much of a pain in the neck it is to get in and out, especially for the passengers (front and rear). Gull wing doors and folding seats would be MUCH easier - I've tried on a Velocity, and it's nice.

     

    Everything's a tradeoff - get good visibility, maybe less weight, but the fit isn't great, it's a bit noisier, and getting in and out is a pain.

     

    With respect to the reclining seat question, the seatback and headrest support structure are part of the fuselage structure, and (at least according to Nat) are very important in the torsional stiffness of the fuselage. I would tend to agree, and that's NOT a change that I would make to my plane.

  21. Originally posted by Spodman

    Burt decided to develop a grass field/rough field capabilty for the Long-EZ so it could be flown anywhere.

     

    Anybody know if this modification made it onto any aircraft, or is it still available? Anybody tried it on a Cozy?

     

    See:

     

    http://www.ez.org/cp25-p3.htm

     

    This is what the COZY has. Remember, the COZY weighs 600 lb. more than the L.E., which is why 6.00x6 tires and the other stuff would be better for the COZY on grass fields. Also, note that gravel and rough fields were still not approved - just average grass.

  22. Originally posted by Spodman

    I've seen references to avoiding rough runways, and others saying only use hard runways. I understand the issue is mainly FOD to the prop, but also a fairly brisk landing speed.

     

    If I want to base a Cozy at a nice, long, grass strip am I asking for trouble? Or is it just not possible?

    There are a number of issues.

     

    As you say, damage to the prop is one, but that can occur on crappy hard surface runways with garbage thrown up by the nosegear as well as on grass/sod/dirt. Some people will take off and taxi with the landing brake down on crappy surfaces to prevent this, and then retract it upon ground breaking.

     

    Another is the small size of the wheels - 5.00x5 are a bit small for lumpy surfaces. Doable, but not optimal. Some people have installed 6.00x6 main wheels, but this will entail larger and higher wheel pants, as well as more drag and a slight speed loss, as well as a minor adjustment in main strut length to account for the larger wheels. Eminently doable.

     

    Another issue is the marginal strength of the stock nose retraction mechanism. It just can't take much of a beating. With one of the electrical nose lifts, I don't think this would be a problem, as long as the casting area is beefed up with the normal set of modifications.

     

    I would also recommend setting the normal ground attitude of the plane a degree or two nose up, rather than at 0, to facilitate lifting the nose at slower speeds.

     

    There are some V.E. (Nigel Field, for one, IIRC) and other canard pilots that do/have operated from grass fields - even some small ones, but it's not very common. With larger mains, an electric nose, higher ground incidence, and judicious landing brake usage, a smooth grass runway should be no problem.

     

    I've operated off of a couple of pretty ratty paved runways (Jaffrey, NH for one) and the COZY tends to bounce a lot, but even with tight wheel pants on 5.00x5 wheels and the stock nose mechanism, it doesn't seem to be a major problem. I haven't hit any large potholes, though.

  23. Originally posted by LargePrime

    Has the CSA ever put old copies on the web like nat does?

     

    No, CSA only has indices online (put there by volunteers not associated with the newsletter, but with Terry Schubert's permission), not the actual newsletter.

     

    And by the way, Nat has never "put old copies on the web". All the newsletters that are on the cozybuilders web site were scanned, digitized, proofread, and put there by me, or by the volunteers listed under each newsletter. Nat gave me permission to do so, and restricted WHEN we could post them. ACS is now telling me that they'd like the newsletters posted as soon as they come out.

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