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Marc Zeitlin

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Marc Zeitlin last won the day on July 6

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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 - 1600 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

1,427 profile views
  1. Hopefully, the pilot still has a head, though, and the back seater can't see through that. The lack of headrest will help forward visibility a bit for the rear seater, but in tandem planes, rear seat visibility forward isn't great. Every other direction is great, though. Yeah, I can see the pants on the plane, but they're the old football style - Tim's goal was to put the newer pressure recovery style wheel pants on the plane and pick up a few kts. I've got them sitting in my hangar... Either convince Tim to bring the plane to KTSP for a Pre-Buy, or pay for me (or someone else competent) to go to Phoenix to spend a day examining the plane. See my website (in the signature) for my services. There are a couple of other folks I can recommend for PB's as well.
  2. That canopy will have exactly the same forward visibility as the standard one part canopy. It will make it harder to get in and out of the plane (which is bad), and will have less "bowing" with temperature changes (which is good). There is zero rollover protection from the headrest (it's a headrest, not a roll bar), so nothing is lost other than a headrest. _IF_ the existing canopy hoop was constructed well, possibly per Mike Melvill's instructions on installing a rollover hoop into the canopy, it will be better than nothing, and possibly better than the original headrest. It's a PITA, but with composite aircraft, everything is doable. A far more reasonable solution would just be to polish them, using something like one of these: https://www.aircraftspruce.com/categories/building_materials/bm/menus/cs/windshieldrestoration.html No. Compressions are almost meaningless - upper 60's are fine, 70's are fine, 45 is fine, _IF_ the engine is making rated power, not using oil, and not making metal. Far more important is a borescoping. I suggest reading Mike Busch on compression testing. I've seen engines read 30, then 77 after a 10 minute run (and need a rebuild), and others that read 45 measured hot after a couple of flights and was perfectly fine for hundreds of hours afterwards. Compressions are a HINT that MAYBE something's going on, or not, but they're hardly the last word. People make WAY too much of compression checks. This plane has flown an average of 11 hours/year SMOH. That's almost always a bad sign for engines - just enough time to let the moisture build up, the corrosion start, and the little bit of running to beat the crap out of it. BUT, if it's lived the whole time in the desert, then the chance of corrosion is pretty low. Pulling a jug would tell, BUT (again, per Mike Busch) has its own risks and costs associated with it. Since it's a rarely used plane, I'd probably want a local A&P who's NEVER SEEN THE PLANE BEFORE to CAREFULLY pull a jug and borescope the cams and lifters. What you ACTUALLY need is a real Pre-Buy examination along with the engine check - none of that will be cheap. This MIGHT be a decent, albeit slightly overpriced plane given the panel, or it might be a $20K - $25K plane that needs a new engine. Strangely enough, I was scheduled to install wheel pants on that plane here in KTSP until weather and COVID got in the way - not sure what the plan is now. Nope. All easily fixable in an afternoon, even if there is a slight fuel leak around the drains.
  3. Well, actually, if you go to the second link and search for "Rotorway", there are five approved designators depending upon which Rotorway model it is - no need for the "ZZZZ". But you're correct that ATC doesn't give a crap about what the FAA's database says the plane is, as long as you call it the right thing when you talk to them. Now, being somewhat obsessive, _I'd_ want to correct the wrong information in the database, and I'd ask the current owner to do so before I bought it - they could contact their local FSDO to get instructions on how to change the incorrect information (and there's no "major change" involved - you're only changing data in the database - you're not actually changing the aircraft). If the owner doesn't want to, since the helicopter's been flying just fine for 15 years with incorrect info in the database (which could be an issue for the insurance company, since THAT's the info they use to determine how much they're going to charge you), you can always make the corrections yourself after you buy the thing. The FAA isn't going to argue with you about it - you just have to fill in and submit the right forms.
  4. Easier to "use", yes. Please provide evidence of FADEC piston engines being more fuel efficient than a manually adjusted fuel injection engine. Thanks.
  5. For aircraft plans sold by companies no longer in business and for which no copyright owner can be found (or who has given up the rights to the copyright), have at it. For the COZY MKIV, owned and sold by ACS, you're restricted to the agreement you sign with them. Al neither has nor needs permission, since he's not selling COZY MKIV plans, but only parts. Only the plans are copyrighted - nothing in any of these planes is patented.
  6. Give me a clue what "fuel leak issue" you're talking about. No and no. MAYBE using some fuel cell foam in the tanks might be useful, but given the relative paucity of evidence of fuel tank fires (the few canard aircraft fires have been engine compartment fires, not tank fires in the air or on the ground, and there have been no "explosions") there's no evident issue with the construction of these aircraft's fuel tanks. Posting a reference to what you're talking about will help others respond in a useful manner, rather than having to guess what you're talking about.
  7. Kent buried the lede :-). If you're building a COZY MKIV, you should join the COZY mailing list at: http://cozybuilders.org/mail_list/ read through the whole http://cozybuilders.org/ website, as well as all the links that Kent pointed you to, particularly Wayne Hicks'. Then read through all the presentations at: http://cozybuilders.org/Oshkosh_Presentations/index.htm many of which will be repetitive, but there's a LOT of what you asked there. Plan on changing as little as possible, within reason, unless you're interested in having your kids be fully grown before you fly it :-).
  8. Were you to bring that plane to me for a Condition Inspection and we found that crack in the bracket, there is no way I would sign off the CI, which says that the aircraft is "In a Condition for Safe Flight". Were I to see that crack on a Pre-Buy examination, I'd tell the buyer not to purchase the plane until it was fixed, or ensure that the plane was trucked to a place where it could be fixed. I'd tell the seller not to fly the plane until it was fixed - maybe ONE flight to the place of repair, but that's it. Landing gear collapse, which is what a failure of that bracket could lead to (however unlikely it may be, and given the crack, it's not ALL that unlikely) can be a catastrophic event. Land hard, hit a small pothole, etc...
  9. Well, I wouldn't say "obsolete", as Kent says - just sub-optimal. Thousands of canards have the old plain bushing style NG-6, and if installed correctly and adjusted on occasion, they work fine. Tapered roller bearing is better, but expensive. Pays your $$$ and takes your choice. Agreed - a close-up of the pic you posted shows a raw nose gear strut with no torsional wraps - you can't see any weave; it's shiny; and there's no peel ply texture. This is a clear indication, in my opinion, of the intensely sub-standard and unsafe work that Mr. Hanson continuously cranks out. That said, the nose gear strut is <$100 from Aerocomposites, and the upper and lower castings, as well as the NG-3/4 are easily salvageable. Heat and a hammer will break them free of the strut, and you can grind out the residue. Or just grind the strut out of the castings, since you're not trying to save the strut. Actually, for bonding, JB Weld is probably superior to flox in a laminating epoxy - the bonding strength is higher. No one in the industry uses laminating epoxies for bonding - various Hysols are common bonding agents, and JB Weld is in type of family. So that was the least of the issues with the nose strut assembly - really, the only issue was that the strut wasn't wrapped - if it had been, you could have easily lived with the JB Weld and older style NG-6.
  10. No, that's not at all what I'm saying. You have a horizontal surface relationship to CG that needs to be maintained (CG forward of Aerodynamic Center) in order to have static longitudinal stability. However it can't be TOO far forward, or else the airplane becomes unable to rotate for takeoff, and TOO stable in pitch to the point that you lose maneuverability. You also need to have an equivalent vertical surface relationship to the CG in order to have lateral stability. Read up on aircraft stability requirements and calculations. Moving CG forward might address the lateral stability issue, but completely screw up the ability of the aircraft to get off the ground and be maneuverable once it does. Everything is a balance, but having as much vertical area at or forward of the CG position (about where the pilot is going to be in one of these planes) is going to make the plane want to fly sideways or backwards, or at least be happy to do so if it happens to be perturbed in that direction. I suggest googling "aircraft design book" and purchasing a number of the ones that come up - Raymer's is good, as is Roskam, just for starters. Also "Perkins and Hage" for "Stability and Control". You cannot design anything other than a standard looking aircraft (think C-172 or Piper Warrior) using "that looks about right" techniques. Particularly with canards and/or tandem wing aircraft.
  11. Are you talking about a horizontal stabilizer or a vertical stabilizer? Vertical surfaces forward of the CG (as any vertical surface attached to the canard will be) are destabilizing in yaw, and would require substantially larger tail vertical surfaces to offset. The vertical (or at least partially vertical) surfaces attached to the wing tips are not far aft of the CG, and will have only a very weak stabilizing effect, particularly due to their small size and cant angle. While interesting looking, this configuration, even with a vertical tail at the aft end of the fuselage, would have poor directional stability at best, and be directionally unstable at worst.
  12. Eureka uses a CNC hotwire machine - it's still hotwiring. Steve does not machine the foam. Accurate, but hotwire, nonetheless. I'm at a loss to understand the belief that fabricating ailerons is rocket science - building a set of new ailerons, if required, should take a long weekend - maybe 3 - 4 days, just because there are about 4 serial cure cycles. Two skins, end ribs, and some reinforcing. Use 7/16" steel rod or tubing to put lead weight inside, and ensure good balance. It's just NOT that hard.
  13. The balance pic you show is from page 7 of the aileron addendum. Look at page 5 - there are two templates that show WL's and external skins. You can use these to create an external level "jig" for determining the WL. In any case, if you balance the VE ailerons so that the top skin is closer to level than the bottom skin, you're good. And that's after ALL paint.
  14. Sand all the paint and excess fill off and repaint it so that it balances correctly. Put the minimum amount of fill, primer and paint on, particularly on the bottom which never sees UV exposure - NEVER paint control surfaces over old paint without removing it. Only then, if the elevator is not in balance, add extra weight, and then only outboard.

The Canard Zone

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