Marc Zeitlin

If David Hanson has touched it, stay as far away from it as humanly possible.

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"

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.

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.

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.

You mean, like Section IIA of the Varieze Manufacturing Manual (otherwise knows as "the plans")?

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.

I have PDF's of the Varieze plans. As well as Defiant, Quickie Q1, AeroCad, Long-EZ, and some others.

Not quite. The Long-EZ shown in that video (and in the video on the main page): https://www.merlinlabs.com/ is one that I have maintained for about 6 years, first for a private owner and then for Merlin, at which I was contractor/employee #2 starting in 2018 (as of 6 weeks ago, I'm no longer an employee). It's currently located in Mojave, CA (KMHV), as are the other planes shown in the video. While Merlin is working towards CAA certification in NZ, the test flying is being done in the US at this time. Achieving Certification Basis is a big deal.

Sorry, Kent, but since you're posting publicly, I'll respond the same. That is not at all my interpretation of what's going on. Since the sensor that is now on the plane is the exact same sensor with the exact same setup as the Dynon EMS was originally installed with, and the sensor was calibrated with a candy thermometer, any statement that the issue with high OT measurements was due to sensor issue is contraindicated by the evidence. Multiple flights with the calibrated sensor verified the high OT's. Only after the oil lines and cooler were cleaned and reinstalled, the OT's returned to a normal 180F - 190F from the previously noted 240F - 260F. Although no debris or blockage was found in either, those were the ONLY things (other than the flapper door removal in the oil cooler ducting) that changed. The problem was NOT the sensor. It may or may not have been the duct door, the cooler or the lines - maybe there was an air bubble somewhere that prevented flow - I don't know. But what I DO know is that it was NOT a sensor issue. Now, it's possible that the issue with high OT's was completely coincidental with the installation of the new EMS. It would be a substantial coincidence, since we did not touch the cooler or the oil lines during the EMS install, but anything's possible. In that case, both the RMI and Dynon EMS's would have been reading correctly. So no apologies needed and no forgiveness required. Zebras, indeed.

Did you purchase a fuselage only? Wings? Canard? Engine? What? If the fuselage ONLY, then there may be other options from what Kent is stating. There is, obviously, always the option of misleading the federal government, but that's NEVER a good idea and IS a crime. People do it, though...

It will be. I did a Pre-Buy on it for a prospective buyer in July - they did not purchase it. Although I flew in the plane and it was safe, there was a fairly long list of issues to be addressed, not the least of which involved the state of the engine. At the time, the price was far too high for what it was.

Usually, they'll be yellowish, but that's no guarantee, and it's no guarantee that it's not if it isn't yellowish. But since 99% of the VE's out there were built with non-alodined and protected wing attach fittings, it's a pretty good bet that any VE you look at will not have protected fittings. Based on my experience and the # of corroded wing attach fittings we know about in the population of ~2K - 4K VE's that have flown, I'd estimate that somewhere around 0.1% - 1% of VE's have corroded wing attach fittings that would compromise strength. Total guess, but a mildly educated one.

The only "fix" for a wing attach fitting corrosion issue is to completely disassemble and remove the metal parts, ensure that the composite spar is sound and wasn't damaged in the process of the original metal fitting installation, and then fabricate new fittings, protect them with alodining and appropriate coatings and then re-install everything with wet hardware. If you don't know what ALL of that means and how to do it, you're not in any position to do the work. As I've stated numerous times before, I believe that it all could be done in about 40 - 80 hours of work, assuming that the underlying composite spar is in good shape. As you surmise, there are many things that could bite you - the composite spar could be damaged, you might damage something in the removal of the corroded metal, or you might have trouble getting all the re-fabricated pieces to align and fit together correctly upon re-assembly. Paying someone $4k - $8k to do this work, with no guarantee of success, seems like a risky path to me. VE's change hands fairly regularly, and they don't fall out of the sky regularly, but there HAVE been at least 4 known instances, in around 2K Variezes, of corroded wing attach fittings. Who knows how many are corroded and haven't been discovered? Nobody. I most certainly would never buy one that had any visible corrosion anywhere on the wing attach fittings. See the picture below for a corroded fitting example - the visible portion, near the hand, is fairly decent looking - you wouldn't necessarily expect that the non-visible portion has severe interlaminar corrosion that has removed over 1/3 of the thickness of the material and damaged the rest.

Actually, the first thing wrong that stood out to me when I was asked about the plane by prospective buyers is the 789 lb. empty weight (per the dataplate - heaviest VE I've ever seen), which makes this a single seat aircraft for a light pilot with full fuel. Plus the corrosion on the wing attach fittings; the minimal time on the engine over the years and the ancient panel. I've already warned two people away from this plane, but I hope it works out for you. This is why I recommend Pre-Buy examinations... Just because something is cheap doesn't mean it's a good deal.

Many people know the real story. A) There is no "51% rule". There is a "major portion" rule, which states that the "major portion" of an aircraft must have been built for "education and recreation" in order to meet the requirements for an Experimental Amateur Built Airworthiness Certificate. Doesn't matter if one person or 735 people built it, as long as the "major portion" of the aircraft wasn't built by people getting paid to do so, but were doing it to recreate and learn. Since a Varieze is a plans built plane, as long as you're not paying someone to build it for you, it WILL qualify for an E-AB AC. Since there are no logs, you can't prove that it wasn't built by someone for $$$, but neither can anyone prove that it was. The chance that an FAA inspector or DAR will refuse an E-AB certificate for a Varieze, if you can talk knowledgeably about the build, is as close to zero as one can get. It's NOT what I'd be worried about. Finish the plane, take pics and document what you did, explain that you picked it up as an airframe built by other folks in their garages, and smile when they hand you the AC. And _IF_ you can prove to the FAA that you know enough about the airplane, you may also get the Repairmans Certificate, of which each plane can only have one and goes to the "primary builder", a term for which there is zero definition. Any of the many builders can be called the "primary builder" and get the RC. And if you don't get the RC, then you'll need an A&P for the annual Condition Inspection, but not for anything else. The EAA has more explanations on their website as well. If, for reasons that elude me, you want to build this Varieze from an existing project, do so - you'll get the AC without an issue.

Glad you think so. I'll give it a shot. a) There's no reason to believe that the interference drag of a wingtip mounted vertical stabilizer is any less than the interference drag of a fuselage (or boom) mounted vertical stabilizer - in fact, due to the very complex spanwise airflow caused by the swept wing and vortices at the tip, it could be more, less, or the same. Only extensive testing could say. b) Less weight - well, less than boom mounted vertical stabilizers, maybe, but given the additional structure needed to mount an inward force winglet at the tip of a wing, only maybe. Less than a fuselage mounted vertical stabilizer - doubtful. c) As I point out in the "Canard Aerodynamics" presentation, the theoretical efficiency gain of the Whitcomb style winglets, upon which the Rutan winglets were based, is never actually achieved because no-one flies these planes high or slow enough to be anywhere near the maximum L/D speed, so the induced drag is a relatively smaller portion of the overall drag, and the reduction in induced drag is tiny, if measurable. And ALL vertical stabilizers (well, almost all, on any plane) will have the rudder integrated with the vertical - it's just a really convenient place to put a rudder. d) The drag component (aft) of the rudder deflection is somewhere in the neighborhood of 10% of the moment contributed by the lift (inward) component. Drag is not the main component (one common misconception), and adds very little to the rudder effectiveness. So, yeah - it "improves" the effectiveness, but not by much, and isn't the reason for the winglets being on the tip. Winglets on our planes are on the tip of the wing because with the swept wing, it's the furthest aft they could get so they could be smaller in area; so that to the extent it exists, they could attempt to be Whitcomb winglets to increase efficiency; and because it was structurally simpler (if not necessarily lighter) than inboard boom mounted vertical stabilizers. It's all a compromise, and it's not at all obvious what an optimal solution is - there are a zillion ways to skin a cat.

Very little of this is correct. You may want to take a look at some of the presentations available at: http://cozybuilders.org/Oshkosh_Presentations/index.htm There are a lot of misconceptions about how these canard aircraft work, are built, and fly, both among those that love them and among those that dislike them. I'm in the first category, but I still find myself debunking old wive's tales and other incorrect information on a regular basis.

Dale Martin is NOT taking over Gary Hertzler's business. Gary can be contacted at: ‭(480) 229-5195‬ and: hertzler@yahoo.com

Until batteries have substantially higher energy densities, you'll have an endurance of just about an hour. Not long enough to actually go anywhere. But as Kent points out, you can see my website by clicking on the link in my signature.

A bit more investigation indicated that this plane may have some (not just a few) major issues. Be extremely wary and get a good pre-buy. And the folks that appraised it for $145K are almost certainly the same folks that apparently created some of the major issues that the plane has. Someone with extreme expertise in Berkuts and whom I trust implicitly with respect to the type indicated the above to me verbally.

Depending upon what you want to do, me, or a few other folks that I can recommend.

If you are considering paying someone to build a substantial portion of the aircraft for you, just realize that doing so (and being honest about it to the FAA) may jeopardize your ability to obtain an Experimental Amateur Built Airworthiness Certificate when you're done. You'd hardly be the only one to have done something like this, but you might (depending upon just how much help you got) have to be willing to lie to the FAA about how much of the airplane was built for $$$, and lying to the federal government is, well, contraindicated. Before contemplating this, I'd very carefully look into the rules surrounding E-AB aircraft and what is and is not allowed. Now, if you're looking for VOLUNTEER help, have at it - that's perfectly fine.

And if you know what your CG is when you reach that point in any stall modality, and you're not comfortable going any further aft in CG, then the AOA isn't calibrated to stall, but just to some arbitrary main wing AOA. Which is all fine and good, but since the main wing AOA at low speeds is going to be very different depending upon where your CG is (fwd or aft) and how heavily you've loaded the canard/elevator, it's not in any way giving you the same information that it does in a conventional aircraft, where it's measuring the AOA of the FORWARD wing, which is the critical one for stall behavior. First, with respect to the meaningless information provided by the SQ2K factory with respect to CG range, you address this directly in your first paragraph, where you stated that you slowly work your way back in CG during stall testing until you either reach the aft limit as defined in the POH or else determine that stall behavior is changing in an uncomfortable manner, and you use THAT as your rear CG limit. So you can/will ignore the POH and determine your own rear CG limit, which then become the aft end of "the approved range" for THAT aircraft. With respect to Chris's testing, with which I'm not totally familiar, the nose bob is definitely more pronounced under power (particularly full power) and the deck angle is VERY steep, so it's an uncomfortable (at least for me) condition. The higher nose bob certainly creates situations where main wing AOA can increase dynamically to too high a level. As a correction to terminology, though, power on stalls are NOT "accelerated" stalls. An accelerated stall means a stall that occurs at more than 1G, NOT a stall that occurs under power. Accelerated stalls (which I tested in my plane thoroughly) can be done with power on or off, and just require a constant bank angle - I stall tested at 15 degrees, 30 degrees, 45 degrees and 60 degrees of bank. The same comments as above apply to accelerated stalls - the main wing AOA will change substantially with CG location, so what is barely OK at rear CG will be more than adequate at fwd CG, and the AOA will display something very different. So my comment about "staying in the approved CG range" still applies - if you're forward of YOUR plane's aft CG limit, there's no deep stall danger (all other blah, blah, blah about vortilons, fuel baffles, ballast, etc. still apply). With respect to power on stalls with larger nose bobs, even if you had an AOA gauge calibrated to some arbitrary AOA of the main wing, a very large bob could put you past that dynamically if you're not being careful, but again, that will have been tested in Phase I in order to set the rear CG limit appropriately (something that the AOA gauge cannot help with, as it's not yet calibrated, and once the testing is done, you no longer need the AOA gauge). I am quite familiar with the usage of AOA gauges in conventional aircraft, and am in full agreement that when it's measuring the AOA of the FORWARD wing, it's an incredibly useful instrument that should be required by 14 CFR part 91.205. And while you are right that the AOA gauge won't HURT in a canard aircraft, it's not giving you any useful information that you don't either already have or do not need, IMO.

If people quote IAS, rather than CAS, the number means absolutely nothing in relation to another aircraft, for what should be fairly obvious reasons. It's a useful # for THAT plane, since it tells you where IT stalls given the airspeed indicator pointing to <something>, but as Kent says, his uncalibrated 55 KIAS might be exactly the same as my 60 KIAS / 65 KCAS (and probably is, at the same GW and CG). If you don't know the airspeed error, IAS is meaningless. With Chris's empty weight of over 1300 lb., MAYBE at very light weights he might be stalling in the low 60 KCAS region, but 50 and 53 KCAS aren't going to happen. There are very few, if any Long-EZ's that stall that slowly, much less COZY's. And as we've probably discussed here a few times, and I discuss in my "Canard Aircraft Aerodynamics" presentation available here, from Columbia, 2019: http://cozybuilders.org/Oshkosh_Presentations/index.htm an AOA indicator on a Rutan derivative canard airplane is kind of useless. There are a couple of folks that have installed them, one on a Velocity, in particular, but the owner could not explain to me what it was indicating to him or how he had calibrated it. He liked it a lot, though.