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Posted

I ended up pulling the trigger and am the new owner of the SQ2000 built by Joel Conard at Payne Field.  Details of his build are at http://www.sq2000.us

As Joel works at Boeing, the quality of his work is excellent which overcomes (at least some) of the issues of taking on such a novel design. Also the Infinity retract is a really nice setup which also added to the appeal of this build.  For the trip south to CA from WA we mounted the SQ on a flat bed 20' trailer canted up to keep the width roadable for the I5.  Video of the 'rig' is here. 

 

A LOT of work remaining but I wanted to introduce the project and start to get to know those folks in the community so you can see another project coming along.  

 

  • Like 4
Posted
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.

Posted

Thanks Marc,

I did read about N2992 and thought the report was invaluable. Not just for the SQ but for all folks Phase 1 testing canards.  Making the impossible turn is hard enough let alone with an untested out of limits aft CG based on 'factory' numbers. And as said, there may have been a 'macho' attitude on having achieved a similar turn on a previous engine failure.

The demise of N416 was also informative as a door failure, again is something that should never happen yet we see it again and again in the canard community.  There are a number of similar Velocity accidents.

However the deeper issues regarding specific to the SQ which are specific to this airframe require a detailed Phase 1 as you say.  I have a short list of mitigation items in my test plan (which may be some way off) which include:

1. Cabin/seat/restraint strength all being reviewed

2. I am using a certified engine.

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.

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

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.

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

etc etc. 

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! 

 

  • Like 2
Posted
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.

  • Like 1
Posted
On 11/5/2020 at 3:05 PM, Marc Zeitlin said:

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...

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'.

This from G5 manual:

"ESP engages when the aircraft exceeds one or more conditions (pitch, roll, airspeed) beyond the normal flight parameters. Enhanced stability for each condition provides a force to the appropriate control surface to return the aircraft to the normal flight envelope. This is perceived by the pilot as resistance to control movement in the undesired direction when the aircraft approaches a steep attitude or high airspeed. As the aircraft deviates further from the normal attitude and/or airspeed, the force increases (up to an established maximum) to encourage control movement in the direction necessary to return to the normal attitude and/or airspeed range"

My thinking is that Garmin ESP would be useful in Phase 1 testing if the test pilot (me) gets a helmet fire whilst distracted by some other 'aspect' of the testing. Underspeed protection can limit any 'premature exploration' of the stall characteristics. As testing progresses and CG envelope found 'safe', ESP can gradually be wound back. Also note that ESP disengages under 200ft AGL so anything below that is up to the pilot.

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.

Posted
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.

  • Like 1
Posted
15 hours ago, Marc Zeitlin said:

 

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.

Yup. Hard to argue with any of that.  Especially when your example sounds like MCAS! Yikes!!

ESP may make things worse not better in the early stages. Thanks for your input here.

I guess it comes back to stick and rudder and exactly as you say, flying the airplane.  Helmet fire or getting distracted is never an excuse for underspeed in a conventional aircraft with decalage. It therefore makes no sense to require a Phase 1 fix for a canard.  Just introduces more complexity that may add to the fire. 

And resisting the impossible turn is part of the same skill set. Trying to automate this out wont work either. The test card and takeoff briefing simply needs to call out the allowable envelope  and assuming its 15 bank, >75KIAS and >1000AGL before a turn to field then the Phase 1 pilot priority is that before all else.  Having done so much short field work in my career I should simply trust that I actually can fly the numbers and don't need no machine to help!

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