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Messages - Joe Person

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31
Hangar Flying / Re: Gross weight question - long EZ
« on: January 13, 2011, 06:18:06 PM »
I'd NEVER operate beyond the per-plans gross weight for an airplane that was built by someone else.  Furthermore, I would also not operate ANY experimental homebuilt above the max gross weight it is PLACARDED for (and I mean, "PLACARDED", as in, "what the original builder specified in HIS paperwork that was reviewed and accepted by the FAA as part of the Experimental Airworthiness process").  If you are looking to buy a Long-EZ, PLEASE get a qualified builder/operator (who knows how to build properly, BTW...) to have a look-over the prospective airplane.  Too many people build crap (IMO, one crap airplane is too many...), and rationalize things away, including the unfounded belief that, "well, it has been flown for xxx hours, so it must be OK...".  We've seen examples of seemingly nicely-built (read, "nicely finished") airplanes that had hidden flaws - several of these flaws have been fatal.



32
Hangar Flying / Re: Varieze Wing Attach
« on: January 10, 2011, 02:39:28 AM »
Yes, 2024-T3 was used for good reason - it provides sufficient strength for the required performance, it is easliy machined/fabricated, and it is cost-effective.  Deeper into the design requirements, properly built sparcaps and BID bearing pads, coupled with the choice of materials for the fittings (per-plans) give higher probability of shearout and/or bearing failure of the fittings (at the .125 thick plates) in an overload scenario (i.e. during a crash), rather than failure of the centersection spar buildup itself (thus yielding a better chance of maintaining fuel tank integrity).

There is more to airframe structural design than static strength analysis & testing.  The balance of materials selected & used is dicated (if the designer is a good one) by a host of design requirements, some of which are not evident when applying just basic engineering evaluation/analysis.

33
Hangar Flying / Re: Varieze Wing Attach
« on: January 07, 2011, 11:57:57 PM »
The "different" wing attach system that was used on Mike Drew's former VariEze (he sold it) was due to the wings being a set of a handful of Jiran pre-fab wings - very few of these wing sets were ever made.  The wing attach system for that configuration is no better/worse than the standard "per-plans" wing attach configuration, with respect to relative complexity, potential corrosion issues, etc., and, working to design that type of wing attach system, adapted to the full-foam-core wing configuration, would entail a lot more engineering, fixturing/jigging, etc., to render.


34
Hangar Flying / Re: Varieze Wing Attach
« on: January 06, 2011, 01:28:50 PM »
Don't know that I'd be considered one of Boeing's experts on metals/materials, but I was a structures engineer for about 17 years in the company, developing airframe structural repairs, mods, etc. 

As far as changing the plans, you HAVE to know what you are doing (TLAR  - "That Looks About Right" engineering will only be successful in certain situations).  I modifed my Eze a fair bit - one inch wider, re-designed strakes (4 gallons more per-side, which required analysis & testing (computed fuel volume & fuel CGs at different fuel quantities & angle of attack, etc., then, actual testing to validate fuel volume & CGs), and half the as-designed anhedral.  Major changes, but I was able to qualify/validate them through analysis & testing, and with an engineering background, I knew how to analyze & test, and how to ensure the results/data were valid.

Many builders will make changes, and call the changes "good" if things merely appear to work.  Again, you have to understand the engineering principles in play if making changes to structural configuration and materials. 

Ti will certainly work for wing fittings, and they may be the "ultimate" VEZ wing fitting design, as long as all pertinent geometry & other design requirements are met. 

Mis-fit the taper pins in the fitting stack-up, and eccectric loading starts to show up on the centersection spar-side of the joint.  This can overload the sparcaps via localized bending at stress levels associated with less than 4 g's of flight-loading.  Pin fit is critical here.

35
Hangar Flying / Re: Varieze Wing Attach
« on: January 05, 2011, 11:43:27 PM »
One other aspect associated with the 2024-T3 fittings - the taper pin fit in the bores formed by the fitting plates' stack has to be very, very good.  For "production" VEZ wing fittings (those assemblies made by Ken Brock), the cutting tooling for making the taper pins and the cutting tooling for making the bores in the fitting plates were ground to the desired taper on the same jig/fixture.  This ensured a very good fit, after machining.  Subsequent to the basic machining, the taper pins were lapped into the fitting bores.  Per-plans taper pins are 4130 steel, with a 125 KSI heat treat, followed by cad plating & baking.  With Nickel Alloy 718 & Ti, you'd have to ensure you achieve an adequate pin fit in the bores, without distorting the pins themselves (with modern digitally-base dmachining, I'd guess this is possible).  The 125 KSI heat treat on the per-plans pins, coupled with 2024-T3 for the fitting plates, allowed fine lapping & controlled wear of the aluminum, and little, if any, corresponding wear on the pins.

As noted, Alodine, or similar chemical film treatment of the bare 2024-T3 is satisfactory for the fittings - I have a VEZ in a marine climate (Puget Sound region), and with the Alodine treatment and wing removal every Condition Inspection, I have never had any corrosion problems.  Good marine-grade grease on the fitting mating surfaces, and LPS-3 or Boeshield T-9 on the bolts has served me well. 

If I were to do it all over, I'd stick with 2024-T3, and have a very light phosphoric acid anodize (no other anodizing process) for corrosion protection and epoxy bond.  I'd not do anything beyond a certian type of phosphoric acid anodize, on account of fatigue performance reduction induced by the more mainstream anodizing processes.

36
Hangar Flying / Re: Varieze question ? Please HELP!
« on: December 12, 2010, 08:37:45 PM »
Shoot me a message at ezejoe@comcast.net, and I can send you pictures of my rolling platform - it is easy to build, mostly wood, and it allows me to do all wheel/tire/brake work, via a salvaged Toyota scissor jack (50 cents at a scrap yard for the jack, no kidding!

37
Hangar Flying / Re: Forward controle pressure
« on: November 03, 2010, 04:07:46 PM »
1.  Elevator contour (check)

2.  Canard incidence (check)

3.  Any recent addition of wheelpants?

Don't go playing around with W&B or revised trim springs until you verify 1 and 2 above.  Note also that the aft CG limit for the Long-EZ was changed from FS 104 to FS 103 in Canard Pusher (CP) 39 (Long-EZ Plans Change (LPC) #116).

Addition of wheelpants will (or will have a high-probability to) change the pitch trim characteristics - it is possible to run out of forward trim at higher airspeeds if wheelpants are introduced onto the airplane where they previously were never installed.

Fly safely,


38
Hangar Flying / Re: What was it like?
« on: October 21, 2010, 09:33:38 PM »
One word:  "Magic".

In a feeble attempt to hitch ride on Bill James' literary coat-tails, the real kicfor me was on a cross-country flight from Havre, MT, to Arlington, WA a few years back in my VariEze.  Westbound, and mimimum winds aloft.  16,500 feet on the altimeter, 3.1 GPH, and 150 - 155 knots groundspeed.  I recall the ponderous thought, somewhere between Missoula, MT, and Thompson Falls, MT, that there I was, halfway to "jet" altitudes, turning a 14+ hour drive into a 3.5-hour flight, with spectacular scenery as far as the eye could see, and "I built this thing in a GARAGE?!?!?!?!"

Yowza!

39
Hangar Flying / Re: TE fences /blended winglets
« on: October 08, 2010, 01:31:41 PM »
Not hung up on anything.  My point is that it will take some level of good structural analysis & design if one is to truely develop a blended winglet for a VariEze.  As for your comparisons, yes there are similarities, but there are also differences in structural geometry that have to be accounted for.  Yes, structurally, these airplanes are very strong (if built correctly), but that does not automatically guarantee success when fiddling with the primary structural configuration, as-designed.  The VariEze main wing was built to the level of "robustness" more for ground-handling loads and flutter considerations, vs. being designed for loads imparted from other sources in the operational envelope.  With the aspect ratio and the limited real estate available at the VEZ wingtips, I'd be diligent & conservative with analysis & testing of a blended winglet design.



40
Hangar Flying / Re: looking for a few good airfoils
« on: October 08, 2010, 12:48:17 AM »
I would expect that the late, great (in so many ways) Mr. Steve Wright (the "Stagger EZ" guy...) consulted with others in the greater canard community to obtain the necessary Roncz canard engineering data/drawings (perhaps he even bought the plans for the Roncz canard from Rutan Aircraft directly and worked from that starting point, as Rutan sold those plansets for many years after he ceased airplane plan sales in 1985).  From experience, none of the many talented designers I have met in the aerospace field (including several of the canard-oriented engineers/aerodynamicists) fit the stereotype of "propeller beanie longhairs".

Regarding the net amalgamation of design data for the Roncz, remember that the design was contracted for and paid for by Rutan when working towards an improved canard airfoil for the Long-EZ.  I would not chalk the relative challenge of getting the necessary design data (airfoil profiles, etc.) to some stingy designer.  With the proper approach, someone may offer to help you acquire said information.

-Another "Propeller Beanie Longhair" (with an optimized propeller and high strength-to-weight beanie...),

41
For Sale/Wanted / Re: Long-EZ Plans & Main Gear for sale
« on: October 08, 2010, 12:36:08 AM »
Plans and the MLG have been sold.  Good hunting!

42
Hangar Flying / Re: TE fences /blended winglets
« on: October 08, 2010, 12:31:15 AM »
Alleycat,

Side-issues above aside (i.e. back to your original question), "blended" winglets, I'm sure, could be done on a VariEze, but, I'd not simply charge off and copy what you have seen on a few Long-EZs and a Cozy or 2.  Such an udertaking involves sufficient engineering experience to: 1.  Design the configuration,  2.  Build a good test configuration,  3.  Properly test (for strength), 4.  Properly test for aero effects (flutter, stability, etc.) and, 5.  Spend the necessary time, money, work, re-work, etc., to make a safe configuration.  If you have the time and money (and skills/knowledge, or can hire it) to do all this, go get 'em.  From my perspective as an aerospace engineer, I'd not tread lightly into such a significant modification.  Flutter qualification alone would entail a rather significant run of analysis and (ultimately) actual testing.

FWIW, the VariEze wing does not have the same structural configuration as the Long-EZ wing.  The Long-EZ wing has a full-span spar/shearweb configuration, whereas the VariEze has a half-span shearweb, slightly more than half-span sparcaps, leaving the majority of the outboard half of the wing a pure foam-supported monocoque structure.

My dollar-three-eighty's worth,


43
Hangar Flying / Re: Where do I begin?
« on: September 20, 2010, 02:14:02 PM »
Walt,

One thing you can do right now, to start familiarizing yourself with the Long-EZ, would be to go to www.cozybuilders.org, and download all the Canard Pusher (CP) newsletters from CP 24 on.  Plan on spending a fair bit of time in research & study, prior to beginning construction.

44
Hangar Flying / Re: Where do I begin?
« on: September 20, 2010, 10:04:54 AM »
Walt,

I assume that with your railroad work, you run on the Hi Line.  You may want to look into a trip over to Havre, MT, to talk to John Anderson - he built a fine VariEze back in the late 80's/early 90's, single-handedly.  If you want to pop over to Havre, let me know, and I'll see what John's availability is.

Meantime, the plans I have for sale are originals.  They have the original front & back covers (Thick light blue heavy paper), and the plastic spiral-binding (entails thin, rectangular perforations across the top of each 11 by 17 page for the plastic binding device).  Additional sheets (full-size templates) are what we call "Size D" drawings - approximately 2 feet by 2 feet).  Copies of plans will not likely have indications that I have noted.  Copies of the "full-size" sheets should be avoided, as reproduction technologies (unless one uses true "one-for-one" copy technology) will typically distort the images.  The full-size drawings are the source for critical shapes (airfoils being the biggie). 

One other thing I'll "second" - lean who to listen to on forums such as this - there is a lot of qualified help out here, and then there are just as many "theorists" who are still building, have not flown/maintained a canard, and who will offer all sorts of advice (some of which can turn out to be unfounded or unsound).

If you want a fast, efficient, long-range airplane that will get you from Glasgow, MT to anywhere else in the country, a Long-EZ is tough to beat (unless it is a light VariEze and your back seater is not huge, or is not there...).

45
Hangar Flying / Re: Where do I begin?
« on: September 18, 2010, 06:21:20 PM »
I have an unused set of Long-EZ plans (all original, not copies), a new (unused) main landing gear bow, and a set of the main gear attach tube/bushing assemblies (new and unused) for sale, FWIW - $700.00 plus shipping for the works.

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