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Marc Zeitlin

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Marc Zeitlin last won the day on January 5

Marc Zeitlin had the most liked content!

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About Marc Zeitlin

  • Rank
    Flying Cozy MKIV N83MZ
  • Birthday 08/06/1957

Personal Information

  • Real Name (Public)
    Marc J. Zeitlin
  • Location (Public)
    Tehachapi, CA 93561
  • Occupation
    Principal - Burnside Aerospace
  • Bio
    www.mdzeitlin.com/Marc/bio.html

Flying Information

  • Flying Status
    Flying - 15200 hrs.
  • Registration Number
    N83MZ
  • Airport Base
    KTSP

Project/Build Information

  • Plane
    Cozy Mark IV
  • Plane (Other/Details)
    COZY MKIV
  • Plans Number
    386

Contact Methods

  • City
    Tehachapi
  • State/Province
    CA
  • Country
    United States
  • Email (Visible)
    marc_zeitlin@alum.mit.edu
  • Phone Number
    978-502-5251
  • Website URL
    http://www.cozybuilders.org/

Recent Profile Visitors

429 profile views
  1. Folks: I am assisting a customer in selling Aerocanard #1, built by Jeff Russell. For more information, see: Any questions, feel free to get in touch.
  2. Geez, what a lot of work for no purpose whatsoever except to satisfy a bureaucracy. In any case, what Kent asked above, and the following comment: I'd just like to point out that AS SHOWN, the wing load distribution will be incorrect, as the moment contribution from the inward forces from the winglets is not included (at least, I don't see any force applied inward to the winglet). This doesn't mean that the test is useless - it all depends on what's being tested, and to what level. But the distribution of forces will not be correct. Jochen Fuglsang had to do the same testing on his COZY III, and he did, in fact, impart the correct winglet forces to the plane to ensure that the moments were correct.
  3. Two things - first, you should ALWAYS get a Pre-Buy examination that YOU pay for when purchasing an airplane. Whomever did the CI on this plane (and since Nate built it and almost certainly has the RC for it, I'd bet a lot of $$$ that he signed it off) was working for Nate, if in fact it wasn't Nate. If you don't see a conflict of interest in using the CI as a Pre-Buy when it was signed off by the guy who's selling the plane (or who works for the guy who is selling the plane), well... And aside from that, as nice a plane as Nate has built here, it's overpriced, although I suppose if someone's willing to pay it, good for Nate (and for the rest of us, as it'll set a high bar for the rest of the planes). The $79K plane is also way overpriced, although it too is a very nice plane. All IMO.
  4. So I have an exceptionally qualified CFII (and you should get an exceptionally qualified canard expert to do a Pre-Buy for you on the LE) in Rosamond, CA that I recommend all my clients to. The first question is, what's the definition of a "signoff"? If they require actual instruction, you can't do "instruction" in a Long-EZ because (unless it's been modified) it doesn't have full dual controls. My CFII does checkouts in his COZY MKIV. If they don't require "instruction", the LE might be adequate, but I/we still recommend doing the training in the COZY, as the right seat is functionally identical to a LE, but the instructor is next to you rather than isolated in the back seat. Safer all around. You know how to contact me if you want to get in touch with him (or me, for the PB).
  5. Other than Perry Mick, who has (at last count, anyway) under 1000 hours on his plane in 25 years or so, please name some other members of the "canard aircraft with Mazda engines who swear by the conversion" camp.
  6. Mr. Quinton Oliviero. Which is a wonderful name, BTW.
  7. I went down and took a look at the plane with Bill O. and the owner. In my opinion, it is NOT safe to fly as is, and needs a LOT of work to make it safe to fly. It's extremely heavy, poorly built and a pig in a poke. I was hoping to be able to tell the current owner otherwise when I went to Chino to take a look (at my time and expense), but I couldn't in good faith say that anyone should fly the thing, even though Bill O. did once. He said (directly to me) that it was almost uncontrollable. The fact that Mr. Hanson signed off a CI on a plane that he himself had built, in my opinion, isn't worth (in the words of John Nance Garner) a bucket of warm piss. There are MANY safety issues with this plane that need addressing - I have a list... For QO, I wouldn't let Mr. Hanson look at any plane I was going to fly in, much less work on it.
  8. Bill has been trying to get the plane down to me for a Condition Inspection for months now, but between his schedule and the weather, we haven't been able to arrange it. It's still in the plan, though, as the weather improves in the spring. If you're truly interested in the plane, you can work with Bill to be here when the CI is done, so you can learn about the plane (and Long-EZ's in general). At this point, you can buy a flying Long-EZ for about 1/2 of what it would cost you to build one. It won't be as nice or exactly what you want, but it'll be flying 3 - 7 years earlier. All depends on what's important to you, what you want, and what your mission is. And you can upgrade/modify it to BE what you want over time, while it's flying.
  9. Can one of you send me her contact info? I may have an interested buyer...
  10. I wish that were true and you would hope that "good workmanship" is self-evident, but that is not the case. I have seen aircraft built by folks that have built multiple canard aircraft that have been average to below average builds and I've seen stuff built by beginners that's phenomenal. I've also seen a lot (wait for it - about half) that are below average builds. Thankfully, even a 5th - 10th percentile quality aircraft will probably be safe, but... There's no way that someone just LOOKING at a few aircraft under construction will have a clue what they're looking at, much less be a judge of what's "good" or even "good enough". I see a LOT of crap out there, and a lot of stuff that looks good from 20 feet away, that when you get close and know what you're looking at, have a lot of issues. The way you ensure a quality project, if you're buying one, is to have it examined by someone with the knowledge to do so, and just because someone has built one before doesn't mean they're qualified. This from someone that does 30 CI's per year, maybe 5 Pre-Buys per year, and has seen over 100 different canards over the past 5 years. Pretty sure that there are fewer than 5 people out there that can say the same, if that.
  11. There are only two reasons that anyone lists aircraft that are worth $35K - $50K for $75K or $117K. And those are that they're hallucinating, or that they've told their spouse that they're going to sell the plane but don't really want to. Because there is zero chance that either one of those planes (or a few of the COZY's that are for sale) will sell for anywhere near their asking price. This MIGHT be a $45K plane, but I'd have to see it to know.
  12. I'm not a lawyer, nor do I play one on TV, but the policy you point to above specifically say, in Section II(d): "While sponsors may adopt more restrictive rules for use of hangars, the FAA will generally not consider items to interfere with the aeronautical use of the hangar unless the items:" blah, blah, blah. So the FAA allows sponsors to be MORE restrictive, as long as you're not interfering with aeronautical use, with 5 "unless the items" definitions of interfering, none of which mention maintenance. I'm not arguing that they're not being assholes by prohibiting maintenance - I certainly believe they are - but it's not a slam dunk that you'd win any argument in court, given the statement that the sponsor can adopt MORE restrictive rules. I think an argument can be made that you're interfering with aeronautical use by prohibiting maintenance, but I also believe that an argument can be made that you're allowed to prohibit it. Don't know who wins that argument. Now, section 22 of the sponsor assurances document is stronger - paragraph (f) says: "It will not exercise or grant any right or privilege which operates to prevent any person, firm, or corporation operating aircraft on the airport from performing any services on its own aircraft with its own employees [including, but not limited to maintenance, repair, and fueling] that it may choose to perform." Which seems pretty clear, BUT, paragraph (i) gives them an out, by saying: "The sponsor may prohibit or limit any given type, kind or class of aeronautical use of the airport if such action is necessary for the safe operation of the airport or necessary to serve the civil aviation needs of the public." So all the sponsor has to do is claim (wrongfully, but they can claim it) that the activity will prevent the airport from being safe. Uggghhh.
  13. A few references: https://www.aopa.org/news-and-media/all-news/2011/may/19/impossible-turn-practice-makes-possible indicates (without any supporting evidence) BG speed and a 45 degree bank. They don't say whether that's BG in a turn or S&L, but since 1G BG is all anyone ever reports, that's what I'll assume they mean. In my plane at the GW's I was at, BG is somewhere in the 80 - 85 KIAS region. This: http://pilatusowners.org/wp-content/uploads/2014/01/US-Navy-turnback-study-1982.pdf is an empirical study that tested success with your parameters - just above stall speed, with different bank angles - 30 degrees and 45 degrees seemed to work the best in these test cases. This: http://peter-ftp.co.uk/aviation/misc-euroga/2013-turnback.pdf is a theoretical analysis, but is backed up with empirical results from testing, and recommends a speed of 5% above the stall speed IN THE TURN. So we may be saying similar things here, due to the differences between stall speeds in the 45 degree bank turns and at 1G (a factor of about 1.2). My airplane stalls, in the configurations I was testing, at about 62 KIAS. So with a 45 degree bank, the stall speed would be 74.5 KIAS. Now add on the 5% margin recommended in the last reference, and we're at 78 KIAS - almost exactly the 80 KIAS I noted was the best case for us. There's no way MY plane could do a 65 KIAS indicated turn at 45 degrees of bank - I'd be below my indicated stall speed and there's obviously be no margin on top of the stall speed. If we assume that (as is always the case) between min sink speed and stall, the descent rate increases, then it's better to be somewhat above stall, which the 80 KIAS gives me, per the last reference's recommendations. I think that the canard capability to get right up to stall speed makes this maneuver a lot safer than in a conventional plane, where a 45 degree bank at 5% over stall speed is pretty much begging for a stall/spin accident.
  14. I've practiced this in my plane as well. We did a Vx climbout until at 100 ft., then Vy climbout. At 400 ft. AGL, we chopped the throttle, and then waited 4 seconds (to simulate the "WTF JUST HAPPENED" reaction time of the average human being before the training kicks in). At that point, I started a turnback, set the airspeed to BEST GLIDE (NOT just above stall - BG is about 80 KIAS, with a 62 KIAS stall speed), and as Kent says, about a 45 degree bank (which IS optimal). It's certainly exciting - making 45 degree turns when 200 ft. AGL and offset a few hundred feet from the runway is not usual, to say the least. But in a COZY MKIV, it works. I think Kent could do it at 300 ft AGL because he didn't wait 4 seconds - if you do wait, I don't think you're making it back. I would tend to agree that 500 ft. AGL might be the lowest I'd try it in a real surprise situation, but it would also depend on what's around, CG, GW, etc. I was very surprised, the first time I tried this, at how close to not making it we weren't - it really wasn't a squeaker - we probably touched down a few hundred ft. from the threshold. We tried a few different bank angles and a few different speeds. The best performance was always at best glide (L/D) speed, and with about a 45 degree bank.
  15. OT here, but why do you think that installing HC pistons is a major change? I wouldn't consider them that, as an A&P. Per 21.93, the only part of the definition that this MIGHT apply to is the "operational characteristics", but I'd argue that "OC's" mean the operating envelope of the aircraft, and installing HC pistons does not change the stall speed or Vne, or the max. G load, or..... and so wouldn't be a major change. Now, it might be a good idea to get new OL's, just so that major changes can be made (many VE's have OL's that prohibit major changes without a new AC, so eventually, you might have to do this), but I wouldn't argue that more HP from the same engine is a major change. Obviously, YMMV.
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