Marc Zeitlin

6 hours ago, Bob Martyn said:

Hi Marc:  I want to explore making the Long EZ into an electric version. I need help with the dimensions for the batteries, controllers and a determination of required thrust and propeller design.

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.

8 hours ago, Kent Ashton said:

This Berkut first seen in July reduced again--was $145,000.  Pics in the ad.  Barnstormers

BERKUT 360 • $120,000 • AVAILABLE FOR SALE • 2006 Berkut 360. S/N 46 TT 275; IFR; ADSB; Dynon D-10A; 215hp Performance Aero engine; Lightspeed Ignition; all logs, manuals, plans; current annual and flying; includes a Bruce’s Custom Cover. Recently appraised for 145k. $120,000 Call for details. Possible trade/part trade for two place SxS high wing tailwheel (Bearhawk; Rans S-21, Kitfox, etc) • Contact Frank Chenevert , Owner - located Flowood, MS United States • Telephone: 773-251-5132 • Posted July 23, 2021

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.

6 hours ago, Bob Martyn said:

I want to make some modifications on the Long EZ and may need an Engineer to check my work. Does anyone know of someone with experience on a Long EZ who can double check my ideas?

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

2 hours ago, Bob Martyn said:

I am new to the community and am seeking help with the completion of the build of a Long EZ in the Florida area. Specifically, I am looking for a person or company that can assist me with the build. Someone who has done this before. Any suggestions are much appreciated.  Bobby

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.

2 hours ago, lelievre12 said:

However I don't think you need to stall the main wing to calibrate the AOA.  The calibration if the AOA could be done in the Phase 1 testing like Chris Esselstyn where he started with FWD CG then slowly worked his way back until the aircraft until started to lose stability and stall recovery was less and less prompt. That setpoint would be what is needed.  ie. set the AOA to the comfortable flight limit, no need for the actual full stall. 

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.

2 hours ago, lelievre12 said:

Well I don't entirely agree with your statement "stalls can easily be prevented just by keeping CG in the approved range". My SQ2000 has a questionable "approved range" which cannot be relied upon. Further,  Chris's testing suggested that power on stalls were more likely to provoke a deep stall at an aft CG. Or put another way, accelerated stalls are harder and more dangerous to explore in Phase 1 testing than simple power off stalls.  Therefore the AOA indicator can help provide additional input in these more difficult  tests pilot so the power off 'comfort' baseline is not crossed. 

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).

3 hours ago, lelievre12 said:

I fly with an AOA in my spam can and have learned much in my circuit work on how close or far I am from the stall in accelerated turns and various weights.  The real merit of AOA is knowing what is happening in accelerated dynamic flight, not static straight and level.  For example, on a gusty day, its quite alarming what your wing is doing unless you add some speed on short final. And of course the critical base--->final turn is very interesting to watch on AOA if you are cranking her over tight because you turned too late.  In a canard at very flight condition you will expect to get a nose drop every time, however knowing the main wing AOA in each of these conditions won't hurt in such a beast as an SQ. 

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.

6 hours ago, lelievre12 said:

BTW, Chris reports 50KIAS stall speed with rear CG. Will a Cozy really fly that slow? I guess if it is light enough, yes.

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.

3 hours ago, Mike75 said:

Any recommendations for finding a prop for a Varieze?  POH recommends 56X70 for an O-200.  Internet searches aren't yielding any great finds, maybe someone can recommend a supplier.  

Get a Hertzler Silver Bullet. Can't go wrong.

3 hours ago, Mike75 said:

I think this POH was written by Burt Rutan himself, so I'm guessing he's an authority?  

A better question might be this:  Are there any Varieze owners out there that use O-200A?

Only just about 95% of the Variezes there. You don't need a special engine.

4 hours ago, velopilot said:

Long EZ N944SJ as previously for sale on this forum: 

These canards are tough...  Seems it buffed out: https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20060620X00771&AKey=1&RType=HTML&IType=CA

So back in 2015, when this plane was up for sale the first time, I did a Pre-Buy on it for a customer. While the owner stated that the landing gear had been totally repaired from the damage in the noted accident, when we jacked the plane up off the ground (I insist on BOTH wheels off the ground at the same time) I was able to move each of the wheels fore and aft approximately 2", with the motion occurring at the LG mounting points in the fuselage, on both sides. Usually, I get a bit perturbed if I can move the wheel 1/4", so this clearly was NOT an acceptable repair, and this was 8 - 9 years after the accident. I informed the owner of the need to re-repair it.

My customer did not purchase the plane - I have no idea what has happened to it in the intervening 6 years, but I'd look damn close at  the LG attachment if I was going to do another PB on the plane.

2 hours ago, A Bruce Hughes said:

The record says that he has a O-320.

But it also claims 180 hp.   Really?

An O-320 with 10:1 pistons, a good EI system and FI can put out 180 HP. Particularly with a good set of exhaust pipes. It's not common, but it's been done.

3 hours ago, SoDak Aaron said:

 It seems that sticking to the Cozy Mk IV might be a better choice...

If for no other reason than that it exists.

1 hour ago, Kent Ashton said:

Saw this one day:  Ad says "Dave Hanson built" but it seems more accurate to say "Dave Hanson built & re-built".  That could be OK but something you'd want to know.  I found the history below on this site which shows it has changed hands once before since Hanson worked his magic.   http://aviationdb.net/aviationdb/AircraftQuery    Hanson has been mentioned before here.  AFAICT, he was the builder/operator mentioned in the accident report.

I have examined multiple aircraft that Mr. Hanson has "built", "rebuilt" or just worked on. Suffice it to say that if anyone ever comes near a Hanson aircraft, they should run away as fast as humanly possible. I have a list of people who also know Mr. Hanson's work and ethics and feel the same way.

37 minutes ago, Ron Springer said:

Another thing to check for is looseness in the main gear. Jack the wheels off the ground and grab the gear legs and yank them fore and aft and check for any play. You can check for corrosion on the outside of the wing fittings, but ideally, you would want to pull the wings off and look at the exposed parts that are inside and hidden from view. I would also look over the condition of the fuel lines and other critical parts if you are going to be flying it soon.

While Ron is correct in all of this, unless you're intimately familiar with canard aircraft and have seen/built/flown them (all three - not just one of the above, and multiple, not just one) you're just not going to be competent to perform an adequate Pre-Buy examination. I wish it were otherwise and that you could just go kick some tires, get a ride, and be fine, but a substantial part of my work is fixing issues with airplanes that didn't get an adequate pre-buy examination, and now the new owner is stuck with expenses they didn't foresee or expect, and may not understand. So, good for my business - crappy for the new owner.

You need the right set of tools, the right knowledge, the right questions to ask, and an understanding of all the issues that have occurred on canards and what do do about them - particularly on VE's, with their uninspectable wing attach fittings that have potential corrosion issues. You need to be able to interpret the <possibly extremely thin> logbook entries, if there are any.

A good pre-buy involves a substantial amount of disassembly, and takes me about 5 hours at the plane, if not more, even with the owner's assistance. Borescope the cylinders, compression check, operations check, etc.

You want to gamble - go to Vegas. You want to buy an airplane, hire someone that knows their ass from a hot rock to examine it for you. Since you're in Socal, well, I know at least one person in the region who knows the difference... :-).

5 hours ago, Mark Wiygul said:

I want to add a question to this thread because I think it's relevant to newbees.,  For someone thinking about taking up aviation, and training in a Cessna 150 (or something similar) to earn a private pilot license, but who hopes to one day own and fly a Long-EZ, what training steps need to be taken to achieve that goal?

What Kent says is true - many folks have just "gotten in and flown them" and not crashed or died. And they are just higher L/D airplanes - they're not magic. But there are differences, and if you get training, you're less likely to screw up either the plane or yourself. While I've done transition flights for around 20 people (not training, as I'm NOT a CFI), I do have a CFII near me who flies canard aircraft (and is also an F-16 and F-35 test pilot at Edwards AFB) to whom I recommend folks for <n> hours of transition training - usually 10, as that's what most insurance policies require. So, figure if you're anywhere near a decent pilot after getting your ticket, another 2 - 10 hours will get you safe in a canard.

Everyone I've sent to my CFII has had extremely positive feedback about the utility of the training.

4 hours ago, Kent Ashton said:

Saw this idea somewhere for compact exhaust nuts that use a 12-point socket...

That was me, on the COZY list :-). Although I got them from Summit Racing - they sell them (as does McM) in both 5/16-18 and 5/16-24, depending on which studs you have. WAY better than the standard nuts, which can be freaking impossible to get at with a wrench, particularly if you have in-cowl exhausts.

3 hours ago, Kent Ashton said:

Pissch!  I can contour an award-winner with a concrete block!  Usually start with a regular block, then go to a red stepping stone for a finer finish.  Next airplanes we build, we will have to hold a contest  🙂

 

Hah! When I was a boy, we'd contour sand with a wet strand of spaghetti, wrapped with hot gravel. You try to tell kids these days, and they won't believe you.

In any case, it'll be a cold day in hell before I build myself another airplane, so this contest will have to occur in another lifetime...

1 hour ago, Kent Ashton said:

Well, whatever floats your boat but this block (16") and aluminum bar have finished three airplanes.  "The poor carpenter blames his tools."  🙂

 

Well, yeah, I could wrap a piece of 80 grit around a ball-peen hammer and contour a plane, but it wouldn't be pretty :-). I'm shooting for optimal, not adequate here :-).

9 hours ago, Upali said:

Can I adopt an aluminum tube similar to the one below? I can make sure it will be flat enough and I am looking for about 36" block.

Yes, that would work, _IF_ the extrusion is perfectly straight and flat. There are few 2x4's on the planet that are flat/straight enough to use for a sanding block - you'd never get a really good contour. 3" is a bit narrow, although it would take a 3" roll of paper.

I used a 1/2" thick piece of plexiglass as large as 3 sheets of 3M wetordry sandpaper, and glued a 2" x 2" AL extrusion to the back to keep it straight. With 3 sheets of paper on it, being about 33' - 36" long, you get really good coverage and straightness/flatness on your contours. 18" is marginal for wing/canard contouring, IMO. The larger the sanding block, the better your contour will be.

8 hours ago, Philg said:

Don't come across planes based at kamuela often. Sure! I wouldn't mind picking his brain a bit or flying over to test fit the plane for me if he doesn't mind 

Contact me via email.

18 minutes ago, Philg said:

Tl,Dr flying in Hawaii sucks 

I can put you in touch with the guy who has the COZY MKIV on the big island (PHMU) if you want to talk to him about shipping, owning, or flying a MKIV.

16 minutes ago, Kent Ashton said:

In a few cases, ferry tanks have been installed but I cannot think of a person who had done that at the moment or flown as far as Hawaii. LA to Hawaii is 2217 NM.  17 hours at 130 KtGS. 136 gallons plus reserve and that presumes you aren't fighting a west wind (which you would likely be fighting).

So there is a COZY III that has "flown as far as Hawaii". That's N22AZ, flown by Damon Meyer, which flew nonstop from Ontario, CA to Portland, ME, a distance of 2258 NM (longer than Santa Barbara to Hilo). I built the rear seat aux. tanks for Damon's plane. He could carry approximately 105 gallons, IIRC, which gave a no wind range of ~3K NM when flying at the Carson speed or a bit higher. He landed with 26 gallons on board, with a tailwind, after 13 hours, at an average GS of about 170 kts.

Damon had the tanks built because he was planning a round-the-world flight, but that's been indefinitely postponed.

Since a COZY MKIV has larger strake tanks and a larger back seat, I'm sure tanks could be built that could carry more than enough fuel. One COZY MKIV had a bladder tank that could carry almost 100 gallons fabricated to fit in the back seat, but the owner never did his planned round the world flight, either.

I'm sure you could have tanks built and installed, and find a ferry pilot, and then it would only cost you about 50% more than having it shipped - at least that was my experience.

50 minutes ago, Gigante said:

Almost everyone has gone either the 320/360 rute looking for more horsies (160/180+) and empty weights close to the 1,000 lbs mark . These are fast birds but need a runway suitable for an F16...

None of that is correct.

About 1/2 of the Long-EZ's out there are using 320's. There are a few 360's (maybe 5%) and the rest are 235's (with a smattering of 290's and other random stuff thrown in there). Empty weights of the O-235 models tend to be 850 - 900 lb, and the O-360's tend to be 900 - 975. There are 1000 lb. LE's out there - generally with O-360's and loaded with other stuff (including a lot of fill). While I understand that the reference to F-16's is hyperbole, I regularly fly my COZY MKIV (essentially the same performance as an O-320 Long-EZ - maybe a bit less, depending) out of 2000 ft strips at Sea Level, when at 1600 - 1800 lb. GW.

50 minutes ago, Gigante said:

I am considering going in the other direction I have a 912 ULS I have rebuilt  with the Edge 1484 big bore and camshaft , this will make the 912 a 120hp engine together with the MT variable speed prop she should perform as well as 150hp in regards to relative efficiency not to mention I suspect it can be built just under 650lbs ... yes the 915is would be nice but $50,000 for an engine is a little much ... any ideas ? 

If you can get 120 HP from a 912, that should perform reasonably well - about like the 115 HP O-235. I'm not a fan of VS or CS props - there's just no need for the extra weight and complexity on a Long-EZ, just to save 200 ft. on the takeoff roll (and you'll give up speed on the top end). But it'll work. Not nearly as well as the 150/160 HP O-320, but like the O-235, as I said.

I've inspected close to 40 or so different Long-EZ's (CI's or Pre-Buys). I've never seen one under 800 lb., much less even close to 700 lb. You're dreaming if you think you can build one that weighs 650 lb. Get it down to 750 - 800 lb. and you'll have done a hell of a job.

16 minutes ago, Kent Ashton said:

reviewed www.cozybuilders.com, the discussions in the Cozybuilders Googlegroup and reviewed some of the many builder websites listed at Cozybuilders.com

www. cozybuilders.org - not .com

23 minutes ago, sweekuh said:

Does anyone have any comps on what this should be worth? Im located in AZ and have been after a canard for years now, and side by side is even more preferable. Any more info would be great... Any prebuy recommendations in the area?

I'd expect an E-Racer to go for a bit more than a Long-EZ with the same equipment and same quality. Is this Lynn Erickson's plane? If so, I'm told that it was very high quality. But without knowing the state of the engine, it could be worth anything from $25K to $60K. The panel, while full, is old, but if everything works, there may be no need to do anything to it. If the engine's pristine, relatively low time, and the plane's show quality (doubtful from the two pics, but you never know) it could be worth more. All depends.

See:

https://www.burnsideaerospace.com/pre-buy-examination-information

for info on the services I provide. Phoenix is about a 2 hour flight from KTSP, and I've done numerous PB's in AZ.

4 hours ago, Emile said:

My most favoured option would be a canard or a tandemwing  where the front wing has the same angle of attack  as the rearwing.   Who can tell me if this would still yield a good pitch stability,  or is the pitch stability lost when the  a.o.a. of the  canard or frontwing is reduced below a certain number.

If you want static pitch stability, the front lifting surface on ANY aircraft must be at a higher AOA and be more highly loaded than the rear lifting surface. While there may be ways to modify the existing kite hydrofoils to have lower drag (which Is what I assume you're after) this rule cannot be broken and still have static pitch stability. So the simple answer to your question is "No, you can't have the same AOA on the front and rear lifting surfaces and still keep pitch stability".