Jump to content

Marc Zeitlin

Verified Members
  • Content Count

    1,243
  • Joined

  • Last visited

  • Days Won

    45

Marc Zeitlin last won the day on October 12 2021

Marc Zeitlin had the most liked content!

Community Reputation

99 Excellent

2 Followers

About Marc Zeitlin

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

Flying Information

  • Flying Status
    Flying - 1600 hrs.
  • Registration Number
    N83MZ
  • Airport Base
    KTSP

Personal Information

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

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

3,041 profile views
  1. In a perfect world, if you could magically build exactly the same aircraft but mold/VB it, I've estimated that you'd save maybe 70 lb, max. The reason is that out of the 1150 - 1200 lb that a COZY MKIV weighs empty, or the 850 - 1050 lb. that a Long-EZ weighs empty, first you have to remove EVERYTHING that isn't composites, and see what you have left, and THEN see what you've got left that's moldable, since all assembly layups are not (and the plane wasn't designed to be assembled in molds or with features that use molds or VB'ing. Then you've got to remove the composite landing gear bows and nose strut. And once you do that, you realize that maybe you've got 300 lb. of composites, all told, that's modifiable without a redesign of the aircraft (which even this would need, to some extent). You're not going to reduce the weight of any of the fiberglass, so what you've got less is fill (but at 12 lb. / gallon for epoxy, MAYBE you can save 10 - 20 lb. of fill) and layup epoxy. If you assume that you can cut the glass/epoxy ratio from 45/65 (decent contact layups) to 55/45 (decent VB'ing), you can get a 100 lb. layup down to 82 lb. So for 300 lb. of composites, you'd save 3 x 18 = 54 lb. Add the 10 - 20 lb. of fill, and you're in the 60 - 70 lb. range. As Kent says, clearly not worth the time and effort unless you're in business manufacturing them. And don't expect hollow wings to weigh substantially less than solid core wings, even with bagging - they won't. Bill Simpson on the Homebuiltairplanes.com forum has posted regarding the comparative weights, and until you get to very large wings, solid core is at least as good from a weight standpoint.
  2. Is there some reason you're not addressing my questions, which could help to determine what, if any, problem you have?
  3. I turn on the fuel pump and lower the gear at the IAF - want to be completely configured and at 90 KIAS upon getting established. Generally, with no wind, I can maintain the 3 degree glideslope with the engine at idle, gear down, and 90 KIAS. Headwind, might need a bit of power, tailwind, might need both rudders. I don't extend the landing brake until I'm below decision height and know I'm landing, if I then need it. Which navigator did you get?
  4. B&C regulators are adjustable - read the instructions. You can set them to the voltage you want. Generally anything between 14.2V and 14.6V is used, and will work fine with most any auto or aircraft batteries. Do NOT go over 15V. Odyssey batteries will charge just fine at 14.4V - just a tiny bit more slowly. You stated that your electrical system is putting out 13.2V - which is it - 13.2V, or 14.4V?
  5. No battery will be charged to any great extent by an electrical system that only puts out 13.2V. You either have a problem with your alternator or regulator, or you're measuring the voltage when at too low an RPM. What alternator and regulator do you have? Have you read the instructions for setting the voltage on the regulator?
  6. No. If you want a canopy, go to: https://www.airplaneplastics.com/
  7. This Varieze, serial # 160, was started in 1976. It has been previously registered and flown as N289E, but is currently deregistered without an "N" number, registration or airworthiness certificate. A previous owner had reserved N26BG for it, but apparently that number was never used. The current owner, who was planning on refurbishing it, passed away two months ago and his widow would like to see it completed and flown. Pictures of the aircraft both when it was flying and in its current state of disassembly are available here: Overall, this looks to me to have been a fairly well built Varieze - the W&B (obviously long out of date, but still somewhat indicative of quality) showed a weight in the high 600's - most of the VE's I see are in the 720 - 750 range, so this is lighter and I BELIEVE that was with the O-235 on it, although I cannot be sure. The contouring of the wings and canard is very good and the interior is clean, from a layup perspective. Although external examination of wing attach fittings is NOT an indication of what may be going on internally, they look very clean with no corrosion whatsoever on either the wings or main spar attach fittings. On the wing attach fittings on the main spar, there is residue from duct tape adhesive. It looks as though it could be corrosion, but it's not. The plane is outfitted with long-ez main gear mounting rather than the wimpier Varieze gear mounting. Along with the gear, there's a large, removable hellhole access panel that allows for gear removal if required without any damage to the fuselage - this is, in my experience, a great maintenance help. Apparently the transparency in the canopy was damaged and a new oversize canopy (not installed) comes with the plane. It has a manual nose gear retract system, but there is a Wright Nose Gear actuator that was never installed as well. What looks to be a brand new Sterba prop in its box also comes with it. The O-235 engine is disassembled - there is no engine paperwork. I'd make the assumption that you'll need to work on the engine. The aircraft is located in Tehachapi, CA, at KTSP in a hangar. Make an offer to the owner - given the prop, nose gear system, and basic airframe, I'd expect an offer of at least $5K, but we'll see how it goes. If there are any technical questions about the aircraft / project, please contact me directly at: and copy the owner's wife, Denise. If you're interested in purchasing the aircraft, contact Denise at: Thanks.
  8. If David Hanson has touched it, stay as far away from it as humanly possible.
  9. The problem, as has been discussed many times previously in this and other fora, is that the worst corrosion is always in places that cannot be seen except by a full disassembly of the wing attach fittings from the spars in both the wing and the main spar. I'm sure I've posted this picture before: but as can easily be seen, one might think that things are reasonably OK when looking at the areas that contain the wing attach hardware (near the hand), but fairly obviously, this is not a safe plane to fly given the extreme corrosion and flaking of the part of the fitting buried in the composite. So "cleaning up" visible portions of the fittings is putting lipstick on a pig. If you do not take the whole fitting apart (probably 10 - 30 hours of work for all four areas - main spar and wings), you'll only be guessing at whether the inside of the fittings looks like this. Hence the disclaimer I put on all VE condition inspection reports that I write: "Both Wing Attach Fittings (ALL VARIEZES) - Due to the inherent design from RAF, it is not possible to check for internal corrosion of wing attach fittings. I recommend removing wings at alternate CI's and checking externally for corrosion, with the understanding that without ~40 - 100 hours of disassembly/reassembly, a full inspection of the fittings and full confidence in the condition of the fittings is not possible. Plan on wing removal for more extensive examination at the XXXX CI. Obey RAF's +2.5G / -1.5G limits"
  10. While it doesn't look like advanced intergranular corrosion, it definitely looks like some sort of corrosion (possibly early stage intergranular) and since there's rust on the steel screws, there's obviously been something going on here. It's not just "schmutz". If there's something like this that's visible on a lower surface AL part, I would be extremely suspect of all of the wing attach fitting parts on this aircraft, and would want to completely disassemble the fittings on both the wing and main spar to investigate. Now, I will say that trying to evaluate material properties via pics on the web is a losing battle, so I could be completely off base here, but I wouldn't fly the plane if this information and pictures were all I had to go on.
  11. The first place to look for information on engine limits is in the engine's operators manual, not on some random online forum. The MFG's info, available here: http://www.franklinengines.com/4a.cfm says that the maximum oil temp is 234F. You don't say what engine you have, but I'm assuming the 4 cylinder Franklin, and I'd be surprised if the oil temp limits were different. In any case, 200 < 234, so no - you don't need an oil cooler if the temps stay below 220F or so. On Long-EZ's, everyone uses an oil cooler (and needs them). On Variezes with O-200's, some have coolers, some don't. Don't know what the few folks with O-235's and O-320's on VE's do - I'd assume that like on the Long-EZ's, they'd need a cooler.
  12. Because you want to turn an airplane that has an incredible useful range into one that has no useful range? No. There's been one electric Long-EZ (Chip Yates'), but he was going for (and set) a speed record for electric aircraft (soon to be broken). He had about a 15 minute endurance. 60 HP is not nearly enough for a Varieze. Emrax makes some nice motors - I fitted a 45 HP Emrax to a Quickie Q1 for a customer, but he still hasn't flown it three years later. It would have had about a 30 minute endurance.
  13. You mean, like Section IIA of the Varieze Manufacturing Manual (otherwise knows as "the plans")?
  14. I'm not familiar with the specifics of the D-fly installation, but I'm going to make the assumption that it's approximately the same as the VE, LE, COZY, and all other canards with 1/8" NPT fittings for fuel drains. There's probably a 1/4" thick AL plate buried in the composite sandwich, and it's spinning between the layers of glass and chewing up the foam. Maybe it was too small - maybe the threads have just galled or something. Don't know - don't care. It's got to come out. You'll need to do some surgery: Drain all the fuel Using a dremel tool and permagrit grinding bits, remove the outer layer of glass around the AL plate, and remove the foam around the plate Sand the surrounding area at least 2 - 3" down to the glass - no paint/fill remaining Pop the plate loose from the internal tank glass layup Sand the internal glass smooth without damaging it or breaking through into the tank Fabricate a new plate - at least 1" square, preferably 2" square Drill and tap it for a 1/8" NPT thread - do NOT tap too deeply - make sure that you can screw in the fuel drain without coming close to bottoming out the threads - this is a guaranteed way to ensure that it'll leak down the road, if it can bottom out Using WET EZ10-87 epoxy/flox, flox the plate into the bottom of the fuselage so that the hole in the plate lines up with the opening in the inner skin - make sure that you don't get flox into the NPT hole Fill the area around the plate with wet flox Layup 2 - 4 plies of BID cloth over the top of the plate, each ply lapping at least 1/2" more onto the surrounding fuselage exterior glass surface (previously sanded) than the previous ply After cure, sand, fill, prime, paint Install a NEW fuel drain with appropriate teflon thread sealant This will take a few hours for the install, and then a few hours for the finishing.

The Canard Zone

×
×
  • Create New...

Important Information