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Long Ez modifications


zies8

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Are the Cozy landing gear legs beefed up to take on the 1000 lb useful load of the Cozy?

The Cozy IV main landing gear uses a bigger, heavier strut. Maybe 25-30% more glass there. The Cozy also mounts the MLG between bulkhead with lots of layups reinforcing the bulkheads. The LEZ mounts the strut on some aluminum angles bolted to the sides of the fuselage. AFAIK, no one has had problems with the CZIV gear mounts, but the LEZ mounts sometimes develop cracks in the angles, and have been known to tear the sides of the airplane in a high-stress landing. For me, the CZIV design is just more robust in that area (and heavier). I'm building a LEZ now using the CZIV bulkhead-mount idea. Just about ready to install the gear. I expect it to be an improvement over the original LEZ mounts. Picture attached

-Kent

Cozy IV flying

LEZ building

post-89-141090155259_thumb.jpg

-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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That being said is the wingspan longer because of the extra fuse width or are the wings the same and just sticks out further from the centerline?

The Cozy IV actually has a larger wing. 88sq.ft. versus 82sq.ft. of the Long.

Adrian Smart

Cozy IV #1453

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I beleive Tony is right about the gear being the factor for gross weight. It states that using the infinity landing gear on the long would increase the usefull load to 2000lbs. Ive seen this on the web sight and I think here in other threads. Also a long with the infinity gear came through the FBO where I work and I have to say it looks sharp.

 

Lynn

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"The Cozy IV actually has a larger wing. 88sq.ft. versus 82sq.ft. of the Long"

 

---> The Cozy designer has stated many times that the Cozy wing is exactly the same size as the Long EZ. The Cozy spar caps are thicker and the wing root is just a tad thicker. Otherwise identical. Can you point me to where the numbers came from?

Wayne Hicks

Cozy IV Plans #678

http://www.ez.org/pages/waynehicks

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"The Cozy IV actually has a larger wing. 88sq.ft. versus 82sq.ft. of the Long"

 

---> The Cozy designer has stated many times that the Cozy wing is exactly the same size as the Long EZ. The Cozy spar caps are thicker and the wing root is just a tad thicker. Otherwise identical. Can you point me to where the numbers came from?

From the LongEz plans/manual: (I own these plans/manual)

Wing Span/Area 26.1ft/81.99ft2

 

Cozy IV From Nats Site (and span verified on my plans):

Wing Span/Area 28.1ft/88.3ft2

 

The Cozy IV wingtips are at BL169, the LongEZ is BL157. But the span from the strake outer to the tip is 99" on both aircraft. So I stand corrected.

 

It appears the extra area Nat quotes is in the strake area. Unless the Cozy IV has a longer chord, I'll have to check that out.

Adrian Smart

Cozy IV #1453

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Upon further inspection, the Cozy IV training edge is from BL31 to BL 169 = 138"

 

The LongEZ is from BL23 to BL157 = 134".

 

Therefore the Cozy IV wing is in fact larger by 4" per side, 8" in total. The wings are not the same, as I posted earlier.

 

It might not sound like much, but 8" extra span at a minimum chord of 20" equates to an extra 1.11 sq ft area at the minimum, when actually the wing seems to be longer at the root section ie. less cowl (if that makes sense). As they say, every extra bit of area counts.

Adrian Smart

Cozy IV #1453

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It's the Cozy III wings that are identical in planform to the Long-EZ wings.

Thats what I said in an earlier post ;)

 

I am glad that is all sorted out now, and we agree. I was begining to think I was going loopy, in a non aerobatic way.

Adrian Smart

Cozy IV #1453

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Wayne and Raki: I have got to learn to use the "quote" feature. You both have Long Ez and Cozy IV plans. Can you tell me what the difference is between the spar cap and shear web layups between the two?

 

I am trying to determine the design perameters that allow the Cozy to have a higher useful load than the Long Ez. It was mentioned that the landing gear is beefier on the Cozy. Is that true of the structure in the wing also?

 

Mike

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Can you tell me what the difference is between the spar cap and shear web layups between the two?

Mike

 

I mentioned it either in this thread earlier, or somewhere else, that the Cozy IV spar caps have about 60-80% more plys than the LongEZ. I could tell you the exact numbers but I am worried that I might be stepping on Nats toes with regard to copyright issues (actually ACS own the copyright now).

 

The webs appear to be the same at first glance.

Adrian Smart

Cozy IV #1453

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I could tell you the exact numbers but I am worried that I might be stepping on Nats toes with regard to copyright issues (actually ACS own the copyright now).

You would not be violating any copyright issues if you were to announce that there are 23 and 17 plies, of variable lengths, for the top and bottom spar caps, respectively.

 

Can you tell me what the difference is between the spar cap and shear web layups between the two?

I wouldn't count on anyone giving you an exact difference between the two designs -- you'll need to do that yourself by comparing the two plans side-by-side.

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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Hey John; I realize the effort it would take to get a technical response from anyone about the exact design criteria on any of the planes. I am in the very early stages of conceptualizing my aircraft. All I am asking for is general statements as to the differences in design so that I can incorporate them into my plane.

I may be stepping over the edge or walking the slippery slope when I say that I as a non engineer would like to modify an aircraft but it seems to have been accomplished by many.

I appreciate the forum and their williigness to share. I look forward to meeting some of you guys at Rough River this year.

 

................Mike:cool: :cool: :cool: :cool:

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Therefore the Cozy IV wing is in fact larger by 4" per side, 8" in total. The wings are not the same, as I posted earlier.

Aside from this difference -- the 4" area closest to the fuselage AND the way the wings are mounted -- the airfoils are identical. The wing drawings are identical -- same size and quantity, just setup at different butt lines (+4" out from center).

 

It might not sound like much, but 8" extra span at a minimum chord of 20" equates to an extra 1.11 sq ft area at the minimum, when actually the wing seems to be longer at the root section ie. less cowl (if that makes sense). As they say, every extra bit of area counts.

You may be correct, but I think the additional lift (if that's what we're talking about) comes from moving the entire wing out 4" on each side to create more leverage to lift additional weight (?).

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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Therefore one could attach Long Ez wings on a Cozy and verca vica?

No. The wing attach systems are completely different.

 

If you want to make mods, you can -- just pick your baseline. Having started with the Cozy, and made a single mode to widen its rear, I can sincerely tell you that you should consider your modifications wisely. If I had to do it over, I would build a stock Cozy IV.

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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The Cozy IV, Cozy III, and Long-EZ wings are constructed using the same techniques. I.e., hot-wire the inboard, center, and outboard foam cores, apply the shear webs and spar caps layups, apply the outer skins, and drill the 3-point wing attach points.

 

However, HOWEVER, HOWEVER... the spar caps and possibly the shear webs are different on all three wings. The spar caps are progressively thicker from Long-EZ to Cozy III to Cozy IV so that the wings can carry greater amounts of weight. I --think-- the distance between the wing attach points are the same on the Long and the III. I --think-- the distance is different on the IV.

 

I can't tell you the differences in the lay-up schedules. It's not that I won't. It's just that I don't have copies of the Long-EZ or Cozy III plans. I only have Cozy IV plans.

Wayne Hicks

Cozy IV Plans #678

http://www.ez.org/pages/waynehicks

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I dont have cozy plans but I have aerocanard and long ez. I believe aerocanard is very similar to cozy (4 passengers). You can compare the differences between both planes. Shear webs are the same 6 plies for both planes. Long ez left aerocanard right.

Mac; Thank you for the graphic.

 

The aerocanard is significantly beefier at the spar! That is very interesting. I am guessing that the added weight of the four place wing spar would only be along the lines of 20 lbs. or so. This structural upgrade would logically be called for if the useful load were to consistantly be at max gross on a Long Ez.

The guys like Chris Eiselson and Jack Morrison Both with 540s on their planes must have made some modifications to their planes in consideration of useful load. Either that or they are using their planes as two place planes.

I am ....ass-u-me ing .... all of this as I do not know their weight and balance figures. It would be very interesting to know how they developed their specifications as they built.

Burt Rutan's original insistance that the 0-260 was the engine for and that modifications that " if you throw it up and it comes down it is too heavy" ( ie; retracts, heaters, auto pilots, etc. etc.) for the Long Ez has certainly evolved.

Has all of this come about just because the structure has proven itself or are there some aviation engineers at work out there or what?

 

Mike

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Long ez left aerocanard right.

The Long EZ spar cap layup schedule you posted does not match the info I have. :confused: I recognize the graphic from the plans... but it doesn't match the table nor is it complete without the "rest of the story" from the CP's.

 

Where did these Long EZ spar cap layup schedules come from?

 

D

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... Long EZ spar caps layup schedules come from TERF.

Wow! That's an eye opener about the TERF CD.

 

There appears to be a rather significant disconnect that I hope the Open-EZ folks are aware of if they're relying on the TERF info during their build. Perhaps the TERF published layup schedule is more than enough... perhaps not. I do wonder where their schedule came from, though?

 

Here's what I know:

 

The original Long EZ plans layup schedules for the spar caps (wings and centersection spar) assume the UNI tape used has a thickness between 0.035" and 0.038". Somewhere along the way, the "standard" UNI tape thickness became around 0.025"... which obviously reduces the total thickness of the spar caps when using the original layup schedule.

 

In response, CP25 (p.6) includes a UNI tape "test" to determine if mods are required. Make a 5-ply layup, cure it, then check the thickness. If it's ~0.18", stick with the plans layup schedule. If it's less (about 0.125" according to the CP), you're using "thin" UNI tape and need to use the revised layup schedule in order to arrive at the required spar cap thickness.

 

The issue was elevated further via a MAN GND plans change (LCP #56) in CP28 (p.9) to drive the point home.

 

I found another "approved" layup schedule published in an "EZE Builders of Fla" newsletter from August of '83. A fellow realized that his UNI ply thickness was only 0.022" and revised the layup schedules further to get the correct thicknesses. The top was increased to an 11 ply layup, the bottom to an 8 ply layup. The schedule was discussed with and approved by Mike Melvill according to the builder.

 

I wonder if the TERF layup schedule is yet another response to changes in UNI tape thickness? However, the ply lengths they published don't square up with the plans ply lengths, either (modified or not) and the graphic depicts the original plans layup schedule. My confidence is certainly shot in the TERF info unless there's more to the story in the text.

 

Does the TERF text provide BL details in addition to the lengths for the spar caps or are you left to guess where each ply starts/stops? Scary...

 

Very interesting info... thanks for posting it!

 

D

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Wow! That's an eye opener about the TERF CD.

 

There appears to be a rather significant disconnect that I hope the Open-EZ folks are aware of if they're relying on the TERF info during their build. Perhaps the TERF published layup schedule is more than enough... perhaps not. I do wonder where their schedule came from, though?

 

Here's what I know:

 

The original Long EZ plans layup schedules for the spar caps (wings and centersection spar) assume the UNI tape used has a thickness between 0.035" and 0.038".

The Terf CD plans say use 0.035" UNI tape, and DO NOT USE UND cloth.

 

As with all plans, the CPs need to be used to get the plans up to date.

 

The TERF CDs contain scans of Rutans LongEZ plans. They are not modified in anyway, however they are March 1980 first edition plans.

 

In the end as long as the CPs are referenced, there is no difference using these to build a LongEZ or first Edition Cozy plans to build a new Cozy.

Adrian Smart

Cozy IV #1453

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I'm afraid IT IS NOT any eye opener about TERF. Like Raiki said TERF contains scans of Rutan Long ez plans and they are NOT MODIFIED in ANYWAY. But they are the first edition so they contain some errors. Not because there is something wrong with them, but because there were some errors in original Long ez plans. For this reason they(RAF) were making newsletters for another 15 years. I decided to make that graph to show the difference between long ez and aerocanard design I thought that would explain why cozy or aerocanard can carry (4 passengers) and long ez can't. Now I see that was a bad idea because now we have another useless thread about quality of TERF. Of course TERF included a lot of text and dimensions to these graphic I didn't published them and I'm not going to do this. If someone is interested please go and buy original plans or TERF Like I did.

I believe that TERF makes great stuff and I'm appreciate them for this. I'm happy about the transaction and I would buy from them again if I had to. All this information which you gave us about layup schedule I have with text included with plans and newsletters which were also included in TERF CDs. But like I said it wasn't my intention to put the whole stuff here. My intention was to show why plans like cozy can carry 4 passengers and long ez can't. So I was going to show that overall thicknes of sparcaps is thicker (thats the whole secret about stronger wings). Everything else is the same (for aerocanard).I think it is really important to know for everyone doesn't matter if they have original or TERF plans, before you start building check this plans at least TWICE with newsletters to be sure they are UP-TO-DATE. I bought TERF CDs, printed them and now I have brand new stuff with complete newsletters, I think this is better option them pay 1000$ for plans on Ebay old and sometimes incomplete. Special if we realize that Burt doesn't support builders anymore. But that was a lesson for me next I should think twice before I publish something.

Mak

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The TERF CDs contain scans of Rutans LongEZ plans. They are not modified in anyway, however they are March 1980 first edition plans.

Hence the "eye opener" I was referring to, raiki. The spar cap layup schedules posted by Mak from the TERF CD do not match what is in my PAPER copy of the Long EZ plans (1st ed, March 1980), nor does the info reflect what the layup schedules should be after updates per the CP's that I referenced.

 

In the end as long as the CPs are referenced, there is no difference using these to build a LongEZ or first Edition Cozy plans to build a new Cozy.

... unless you start with the schedule provided by TERF under the assumption that it represents the original/unmodified March 1980 1st ed plans schedule and blindly modify it using CP info. Then you'll end up with spar caps that don't match the plans.

 

I'm afraid IT IS NOT any eye opener about TERF. Like Raiki said TERF contains scans of Rutan Long ez plans and they are NOT MODIFIED in ANYWAY.

Hold on a sec, Mak. I apologize if you felt like I was attacking you or TERF. That wasn't the case, Ok? :o

 

I understand and appreciate the intent of your original post for Mike. However, when I saw the layup schedules something didn't look right. I went back to my PAPER Long EZ plans (1st ed with the mods per the CP's) and found that your info from TERF and my info from the plans+CP's do not match... hence, my questions and concern AS A FELLOW BUILDER. Nothing more.

 

Now I see that was a bad idea because now we have another useless thread about quality of TERF. Of course TERF included a lot of text and dimensions to these graphic I didn't published them and I'm not going to do this. If someone is interested please go and buy original plans or TERF Like I did.

I do not believe that identifying the source of the discrepancy between the original plans + CP's and what TERF is publishing is "useless" info... and I appreciate you publishing the TERF info. I want to know whether TERF knows something I don't and whether I should update MY layup schedule (plans + CP's) to reflect what you published.

 

I was hoping that in the spirit of this forum (you know... sharing info about our builds) that you would look at the TERF info and see if they identify the source for the revised layup schedules. That's all...

 

I think it is really important to know for everyone doesn't matter if they have original or TERF plans, before you start building check this plans at least TWICE with newsletters to be sure they are UP-TO-DATE.

See, we're on the same page (... we're just using different plans). ;)

 

Seriously, I consider this a "check" of my plans because your TERF info doesn't match what I'm using... and I want to know what is correct.

 

If you wouldn't mind looking to see if TERF mentions the source for the revised layup schedule I would certainly appreciate it. If you do mind... well... that's Ok, too.

 

D

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