Marc Zeitlin

20 hours ago, AYB said:

I got very, extremely impressed with Q2 and thinking about building my own. But there is a thing about it that may be a show-stopper — I have a dog that I definitely want to keep with me.
Also, that dog is about 30 kilograms, so I'd like to avoid overweighting the plane.

Another thing I'm concerned about is the range: about 800 kms will be too short for me, since there are not much places to fly to from Israel and I need to have 1200-1500km hops range to reach Europe. Any complete projects with doubled range you're aware about?

With all due respect, you've decided on an airplane that doesn't fit the mission you've defined. That's backwards. Determine the mission (one or two people, 30 kg dog, some baggage, 1500 km range). THEN go find a plane that can fill that mission.

I will tell you that if you're partial to canard planes, a COZY or Velocity will do it with no modifications whatsoever. If only ONE person and a dog, then a Long-EZ will fill the mission.

Mission first, THEN airplane.

There is no way to modify a Q2 to do what you're asking - stop thinking about it. For weight, CG, structural mods, fuel capacity - not going to happen.

57 minutes ago, Ron Springer said:

2) I can do what Marc did above. I assume he used a copper pipe with teeth as a drill???

First, I use the longest jobber drill I've got - maybe 2 ft, 3/8" dia. Then switch to AL tubing with teeth on the end. Doesn't work great - tends to tear the foam a bit and clog up easily. But I haven't found anything better, yet.

58 minutes ago, Ron Springer said:

I also assume I will need to drill a hole through the outside winglet attach layup? Can't go around it, right? Any recommendations on hole size or just keep it as small as possible?

No holes through primary structure. The hole I drill is from the area FWD of the LE of the winglet, where the lights will actually attach, aftward to the end of the aileron cove. Since there's no shear web in the outboard wing of a Varieze, the hole only goes through foam. I remove the aileron so that I can also drill from the aileron outboard, and pray to Cthulhu that the holes meet somewhere about 1/2 out.

Ha. Picture's worth (in this case) 75 words.

Interestingly, this (remove the section of the wing aft of the dotted red line):

is what the TE of my right wing looked like after the prop hit it on its way to Joshua Tree NP 9500 ft. below us in 2006. The prop took off the TE outboard of the aileron, plus a little bit of the TE of the aileron over the last 4 - 6 inches. Plus 2/3 of the lower winglet. Left me with this:

souvenir, stuck in what was left of the lower winglet.

While I was mostly concentrating on other stuff at that point, I did not notice any substantial difference in the flight characteristics of the airplane on the way to the landing at Desert Center.

When Mike Melvill flew me out to pick the plane up a few days later with a new prop and extension, as well as a bunch of AL tape, we taped up the TE of the wing to close out the exposed foam. It's called speed tape, right? He chased me home in the company Duchess, and I never went faster than 120 KIAS. Once again, there was no discernible difference in flight characteristics on the way home. After the flight, we ruminated on why anyone puts the last few inches of wing on the wing if it doesn't make any damn difference to how the airplane flies. But I fixed it back to the plans design anyway, not being an aerodynamicist :-).

12 hours ago, lelievre12 said:

I am finishing my SQ2000 project which has molded (not foam core) wings.  The 'as molded' trailing edge on my main wing is a pretty fat radiused edge which is ~1/4" radius (1/2" top to bottom)...

Looking at the Eppler 1230 design I see that the trailing edge is 'sharp' so the question is "what trailing edge are other folks using" on their Eppler main wings?

Trailing edges should be neither rounded nor sharp. Both lead to vortex shedding, drag, and unstable airflow. You want the TE to be a flat squared-off surface, no less than 1/16" thick and no more than ~1/8" thick, ,although as you say many Lancairs have TE's with 1/4" thickness on the squared-off surface.

This is particularly important (not to have a sharp TE) on the ailerons, so as not to affect control forces.

12 hours ago, Bugstrider said:

I was just wondering for those out there that own a Vari, how difficult would it be to retro fit a flying Vari with navigation lights for night time ops, including a possible landing light modification?

I've done it on two VE's. The hardest part is drilling a hole from the wingtip to the end of the aileron cove for the wiring without drilling through the top or bottom skins. Other than that, it's just running some wires and creating hard points in the wingtip for the LED lights to mount on to. 1/2 - 1 day's work, maybe.

Landing Lights on VE's are more problematic, as there just really aren't many places to put them. A fold down one, like on the Long-EZ, could be done, or something like this:

https://www.aircraftspruce.com/pages/el/landinglights_aveo/aveo_11-18453.php

on the bottom of the fuselage, next to the nose gear wheel well.

41 minutes ago, Voidhawk9 said:

In a year and a half, the only responses have been people asking if it is still available. Probably safe to expect it is either not available or the seller is no longer motiovated to sell it as he has not responded in that time!

C'mon, Cameron. Are we there yet? Are we there yet? Dad - are we there yet? When are we going to get there? Are we there yet?

1 hour ago, Bugstrider said:

Been looking at a Long that has a O-290-D2 that has been sitting for a long time.  Back in the day, it was dissembled, inspected and reassembled with updates and then parked.

There is nothing intrinsically wrong with an O-290-D2. I've had a few customers with O-290 powered LE's. Obviously, the performance will be in between the O-235 and O-320 LE's.

The operative words here are "has been sitting for a long time". ANY engine that's been sitting, unused, for a long time, particularly if it was not pickled or preserved correctly, is almost certain to have corrosion issues unless it's been sitting in the Gobi desert. Which then implies that at least an IRAN is required, if not an actual overhaul/rebuild. The engine would require a VERY extensive inspection to determine its actual state.

One of my customers with an O-290 had Lycon upgrade it to an O-320, so that's a possibility as well, if the engine's in good shape.

7 hours ago, lelievre12 said:

... I'm wondering to what extent the Whitcomb 'mini' lower winglets are as effective as full chord.

They're there for different reasons - one for reducing spanwise flow (large lower winglet) the other (small lower winglet) for reducing drag. So, apples and oranges.

7 hours ago, lelievre12 said:

I wonder if Nat tested them?

No - he just copied the large lower winglet that Burt designed for the Long-EZ. The COZY/etc. wings are all identical to the Long-EZ wings, aerodynamically. Only the strakes and spar cap structures are different.

4 hours ago, lelievre12 said:

I see these lower 'mini' winglets on older Vari/Longeze.  

I'm sure there is a long history of discussion about them. Can someone point me where I can read more?

At the moment I have only upper winglet/rudders (Berkut/SQ2000/ERacer style) and wondering about the tradeoffs the between nothing, 'mini'  winglets and full size lower winglets Cozy/Velocity style.  

 

Those are the first implementation of the original "Whitcomb Winglet" design, invented by Dr. Richard Whitcomb. Look that up. Burt was the first to use Whitcomb's theories on an airplane winglet. The idea was increased efficiency / lower induced drag.

The standard LE/COZY/Velocity/etc. slab winglet is there because it assists in extending the rear CG limit for deep stall protection. They also assist in aileron effectivity at low speeds. Some people remove them because they don't like the aesthetics or believe it will reduce drag (which it will, but not by anything you could measure at our normal cruise speeds). On a Long-EZ, where you don't have to worry much about deep stall because it's relatively easy to keep the CG fwd of the 103" rear limit since there isn't a lot of variation in front seat weight, removing the lower winglets isn't a really big deal (Berkut has the same argument). But in a COZY, where there is a LARGE CG motion with front seat loading and it's easy to get too far aft if you forget to put in enough ballast when flying solo, the lower winglets are more important. Extra margin... On a four seat SQ2000, I'd DEFINITELY have lower winglets, for all the same reasons as the COZYs.

Note the empty weight of 773 lb. That's an INCREDIBLY heavy O-200 VE, particularly since it's got manual nose gear and an ancient (probably original) panel. With 26 gallons of fuel (full fuel) a 181 lb. pilot (no baggage or passenger) will put this plane at the extended MGW of 1110 lb.

This is a single seater for a relatively (given the size of US persons these days) small person...

11 hours ago, Kent Ashton said:

Stop-crack drilling doesn't work on fiberglass like it works on aluminum or plexiglass.  On fiberglass it just cuts more of the individual strands and makes things weaker.  Marc's fix will be fine.  After the surface is filled, you will likely not be able to detect any bump

And it's the inside, so it won't be filled or finished, so no one even cares what it looks like :-).

34 minutes ago, sixfivelrp said:

Here is my dilemma, I had a small slip with the multitool trimming the canard cutout on the fuselage. My issue is if i do the standard repair of one inch per layer, i will end up grinding way out into the good stuff, as this is in the corner where the f22 reinforcement layup is.  See pics.  Second opinions are appreciated.

While this cut seems to go through the inside layups, including the 4 BID reinforcement (given what the pic looks like), the area under the torque tube cutout is a low stress region. What _I_ would do here is to fill the cut with flox and then add 4 plies of BID in the same orientation as the reinforcement layups, feathering them in. The first ply would be 1" long, the next 2" long, etc.

And call it good.

And obviously, in the future, be really careful when grinding/cutting/drilling into major structural members.

3 hours ago, macleodm3 said:

There is a 1” diameter hole at each end of the spar... antenna wires and wingtip light wires exit out these holes.  These holes are where cabin air freely exits.  The holes are protected from weather, so a flapper typically isn’t required.  

This is certainly one place where air might exit (that I forgot to mention), but in my case, I have covers over the main spar openings aft of the seats in the cabin, with only very small openings around some wiring, so while this might be part of where the air is going, it's hard for me to believe that all the air coming in through my vents is going out through a couple of 1/4" annuli around some wiring bundles. If you don't have a cover over the spar, then yes - this could be a major source of exit air.

3 hours ago, lelievre12 said:

I am wondering what folks do regarding letting cabin air back out.  I have arranged my inlets just fine but cant see any info in the build about how that air is getting out again!

Nick Ugolini is the only person that claims to have sealed their cabin up so tight that they actually need to provide a dedicated air outlet. Given the leakiness of most of these planes, it's rare that a dedicated outlet would be required. I can tell you that on my plane, I've spend a lot of time sealing my nose gear area, canard perimeter, elevator offsets through the fuselage sides, fuselage top perimeter, and canopy seal. It's pretty tight, with no noticeable air leaks in any of those places. My engine muff heater will keep my feet warm and the cabin at 30F - 40F above ambient. My two large diameter air vents:

https://www.aircraftspruce.com/catalog/appages/largealumavblack.php

will just about blow me into the back seat when fully open, taking in air from the NACAs on the fuselage sides.

But I have no dedicated outlet(s), and I can safely say that I have NFC how the air gets out, but it obviously does. Maybe through the two holes in the top of the landing gear bulkhead area, even though they have loosely fitted covers? Maybe through the electrical conduit channels into the lower cowl? Maybe through the rear curvature of the canopy, above and behind my head, so I wouldn't know if air was flowing in that area? No idea. Almost none of the planes I work on have dedicated outlets, and no-one complains that they can't get air to flow in through their cooling vent.

Now, that doesn't mean that you shouldn't install a dedicated vent, and I've seen a few in the turtleback, next to or aft of the passenger's head area. If you have one and don't need it, it doesn't hurt, but if you don't have one and need it (unlikely, but possible) you'll want one.

My $0.02.

50 minutes ago, Kent Ashton said:

IMO, the Cozy fiberglass strut and wheel pant are pretty aerodynamic and the speed increase you'd get from retracts (5-6 kts?)...

If you even get that. John McAvoy, after a 3 year retrofit on his Long-EZ, noted that at some altitudes he was getting exactly zip for a speed increase, and at best a 2- 3 kt. increase (IIRC) and still had the loss of fuel capacity.

I'm 100% with Kent here - completely against retractable mains on a standard Long-EZ or COZY that cruises in the 160 - 180 KTAS range. Do a good job on your wheel pants, gear leg fairings and intersection fairings and you'll be in about the same place with far less maintenance and cost.

1 hour ago, Rich Meyer said:

Is there an online repository with a Defiant POH?

I have a Defiant POH PDF. Email me.

On 11/19/2020 at 12:42 PM, Cmead said:

Where are you all mounting the control module for the LSI ignition system?

Depends on the type of plane. As Kent indicated, in COZY's and LE's, they generally go on the firewall above the spar. On VE's, that's not available, so they tend to go in the hellhole (which is a nightmare, unless you've got a hellhole access cover underneath the landing gear, and even then...

Some VE's have an enlarged hellhole access hole in the rear seat seatback, and mount the box on the back of a cover for the hole, with service loops for the wiring.

3 hours ago, montun23 said:

I have seen ppl hang it along the walls, using straps along the leading edge, not very comfortable with that.

Works perfectly.

2 hours ago, lelievre12 said:

The newer Garmin AP have 'ESP' which is a bit like the lane keeper steering in newer cars. It works a bit like a stick pusher when underspeed is detected but at all times the pilot is in 'control' and the AP is 'off'...

Of course if it all goes to hell and the Garmin goes beserk then there is always the CWS and APoff buttons on the stick.

So the manual says that if you have ESP turned on, ESP takes effect when the plane is 500 ft. AGL and the A/P is NOT engaged. I don't see anything about being able to disengage it with the CWS or A/P "off" button, since it's on even when the A/P is off. Now, I don't know if you've got a G3X or a G5 - with the G5, low airspeed protection is not available, but with the G3X, it is.

While discussing random stuff yesterday with an Air Force F-16/F-35 test pilot friend with whom I work on various projects and also whose COZY MKIV aircraft with a full G3X/GNS750 panel I maintain, he mentioned that he doesn't like the ESP functionality, because it will sometimes do unexpected things. A similar one of which, described below, has happened to him:

Imagine that for some reason, your IAS isn't working correctly - blockage in the pitot tube, bugs in the pitot tube, leak in the pitot tube - whatever. It's early in your test flight period, and you don't know the plane well yet. And you've told the system that the minimum airspeed you want to maintain is 75 KIAS. So you take off, but your IAS stays at 43 KIAS, for some reason. You've had enough instruction in a COZY MKIV to realize that you wouldn't be in the air if that's true, and that judging by the attitude of the airplane, you're probably at 80 - 90 KIAS. You get to 500 ft. AGL, the ESP freaks out and bunts the plane over to try to maintain 75 KIAS, but keeps pushing harder because all it sees is 43 KIAS. You're now impersonating Popeye, wrestling with a new plane early in the Phase I period that's trying to dive into the ground, while trying to figure out WTF is going on, and trying to figure out how to get into the correct menu to turn the F-ing ESP system off, if you even figure out that THAT's the problem within the next minute or so.

No thanks. No A/P, no retracting landing gear, no ESP, no automation (except data collection), until you've determined manually that the aircraft is working correctly per the plans and POH, and using electronic assistants, as much as I am an advocate for them in a PROVEN aircraft with KNOWN characteristics, is not what I'd recommend.

2 hours ago, lelievre12 said:

3. Testing at Castle (KMER) which is 11,800 feet long of wide concrete runway if that is permitted. Lots of room for taxi  / ground effect work.

Phase I activities are done regularly out of KMER - that's where the Valkyrie tests are ongoing (another project with which I had a small bit of review work). No problem testing there, and yes - with the huge runway and flat ground around, it's a good place for testing.

2 hours ago, lelievre12 said:

4. Will set the Garmin GFC to include stability protection below a set test number (80 KIAS initially?)

Hmmm. Not sure how I feel about that - I'd probably refrain from turning the A/P on until I knew how the plane flew...

2 hours ago, lelievre12 said:

5. Will do a first principles reset of the CG envelope and start only with forward limits.  I agree that the Glassic numbers seem optimistic and arbitrary.

Given the similarity in wing/canard positioning and fuselage size to the COZY MKIV, I'd normalize the COZY FS's to the SQ's, and use the COZY first flight box as my starting point, near the front. Not the front of the whole envelope.

2 hours ago, lelievre12 said:

6. Ensure vortilons and stability aids are actually fitted! I note one flying SQ also has aileron fences. 

Aileron fences work well on the highly swept VE wings. On Long-EZ / COZY wings (same as SQ) the reports are unclear - some folks say they made a difference in low speed handling - others say there was no difference. I have no data on this one way or the other - I haven't tested them on my plane (probably should, someday - its on the list).

2 hours ago, lelievre12 said:

And of course before the flights I hope to meet you and maybe fly you up for a candid  appraisal of progress. Of course others are welcome anytime at KVDO to share experience at anytime! 

Be happy to come up for a visit. Once or twice a year we fly into Gnoss to go sailing with a Long-EZ friend out of Sausalito, where he is a member of a sailing club. My wife loves Sausalito.

1 hour ago, lelievre12 said:

I ended up pulling the trigger and am the new owner of the SQ2000 built by Joel Conard...

To the extent that one can tell from digital pics, Joel's work certainly looks top-notch. Obviously a good thing. I would suggest that you read the accident reports here:

http://cozybuilders.org/N2992_Accident_Eval/index.html

and here:

http://www.kathrynsreport.com/2012/08/1-dead-in-crash-of-single-engine-plane.html

and make whatever changes to the aircraft's doors and seats are necessary to increase the safety of the plane. Given it's E-Racer heritage, I'd also recommend (not that I don't recommend this for ALL E-AB aircraft, but especially for kit aircraft that were never fully tested by the MFG's) that you perform an intensely complete exploration of the performance envelope during the Phase I period, both structurally and aerodynamically.

When I examined the SQ2K that's for sale in San Diego (and I strongly recommend that no one ever purchase that plane with the intent of flying it, as it should never leave the ground again) I saw many design and fabrication issues that I thought were marginal. I do not know enough about what the kit is or the plans say to determine whether those marginalities were part of the design, in which case modifications may have to be made (rudder pedal attachment to achieve necessary stiffness, Master Cylinder mounting, fuel vents inside the cabin, etc.) or whether they were builder mods, in which case you won't have to deal with those stupidities.

I'm also not at all a fan of the glassed in nature of the canard - I think that's a maintenance nightmare in the case of needing to modify or repair anything.

But it does look like you got the best of the breed in Joel's project, and I hope that you can get it flying safely and with the testing necessary to prove that it is so.

1 hour ago, lelievre12 said:

1. Plan View: prop flange square to centerline at BL O" (no P factor correction) and ;

2. Elevation: prop flange center at WL 21.5" (1.5" below top of longerons) with a 2 degree downthrust (aft higher than for'd). 

3. Prop flange station = 41-42" aft of firewall. 

Does that sound right to others?

(1) and (2), yes. Since the longeron incidence angle will be about 1.5 - 2.5 degrees (nose up) in cruise, that puts the thrust line just about level in cruise.

(3) is approximately correct, but will depend on what engine you're using and who you bought your engine mount from (or how you fabricated it).

4 hours ago, Evan said:

Im gonna do a little bit of work and fly it as much as possible needs mostly finish work

everything works on the plane

Ummm, I'm pretty sure you were informed that the engine needs a rebuild - that there's substantial corrosion inside, right? There's no way you should fly that engine in it's current condition. And that corrosion was diagnosed a couple of years ago, so it can only have gotten worse (corrosion never fixes itself...).

7 hours ago, A Bruce Hughes said:

I also have cotton fibers at OLM but I cannot find the order number to get some from ASSC.

I went to the Aircraft Spruce website and searched for "flox". This was the first link:

https://www.aircraftspruce.com/catalog/cmpages/flockedcotton.php

1 hour ago, jclisham said:

... I'm curious as to if anyone can hazard a guess as to by how much?  Are we talking 800 ft/min climb on an 85-90F day at field elevation of 635ft good?  Or worse/better at 1500lbs?

Joe D. gave you some useful reference points. I'd point you to pages 52 through 61 of the POH, which shows performance for an O-235 LE. That's at an MGW of 1000 - 1400 lb, so at 1500 lb., figure a bit worse than the 1400 lb. curves. CG actually has at least as large an effect on top speed as MGW, so flying at the rearmost CG position (103") will get you the best performance.