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Wing sweep and recent crashes
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gboothe5(at)comcast.net
Guest

Posted: Wed May 16, 2007 1:40 pm Post subject: Wing sweep and recent crashes

Andy,



When my daughter was in High School she came home one afternoon very upset

about the fact that girls were not allowed on the wrestling team. After a 30

minute discussion about the pros & cons, I asked her if she wanted to join

the team. She admitted that she never had any intention of doing that!



So, now, I'm asking you, after all this intellectual discussion, after

looking at your web sight and all your careful work, are you going to

install more ribs & beef up your spar?



Gary Boothe 

Cool, CA 

601 HDSTD, WW Conversion 90% done, 

Tail done, wings done, working on c-section



--

ashontz

Joined: 27 Dec 2006
Posts: 723

Posted: Wed May 16, 2007 1:58 pm Post subject: Re: Wing sweep and recent crashes

 	  gboothe5(at)comcast.net wrote: 	
		  Andy,



When my daughter was in High School she came home one afternoon very upset

about the fact that girls were not allowed on the wrestling team. After a 30

minute discussion about the pros & cons, I asked her if she wanted to join

the team. She admitted that she never had any intention of doing that!



So, now, I'm asking you, after all this intellectual discussion, after

looking at your web sight and all your careful work, are you going to

install more ribs & beef up your spar?



Gary Boothe 

Cool, CA 

601 HDSTD, WW Conversion 90% done, 

Tail done, wings done, working on c-section



-- 	




I'll check with Zenith first as far as official analysis goes. I'm not looking forward to extra work, but if I feel it needs it and there analysis shows no negative effects I will do it. I don't think I'll mess with the spar. I have .040 for spar cap angles as it is, the extrusion was just an after thought. It wouldn't be too hard to install more ribs, making them will be a pain in the ass because I hated making the forms. They're reall time consuming.

gboothe5(at)comcast.net
Guest

Posted: Wed May 16, 2007 2:17 pm Post subject: Wing sweep and recent crashes

Whew!!! I'm glad to hear you say that! I truly hope that someday we can fly

wingtip to wingtip and compare the oil canning we each have in our

respective wings - you in an XL and me in an HDS. 



Of course, I'll be flying behind a Corvair, so I may have to throttle back a

little.... 



Gary Boothe 

Cool, CA 

601 HDSTD, WW Conversion 90% done, 

Tail done, wings done, working on c-section



.. I'm asking you, after all this intellectual discussion, after

 	  Quote: 	
		   looking at your web sight and all your careful work, are you going to

 install more ribs & beef up your spar?

 

 Gary Boothe 

 Cool, CA 

 601 HDSTD, WW Conversion 90% done, 

 Tail done, wings done, working on c-section

 

 --


	




I'll check with Zenith first as far as official analysis goes. I'm not

looking forward to extra work, but if I feel it needs it and there analysis

shows no negative effects I will do it. I don't think I'll mess with the

spar. I have .040 for spar cap angles as it is, the extrusion was just an

after thought. It wouldn't be too hard to install more ribs, making them

will be a pain in the ass because I hated making the forms. They're reall

time consuming.



--------

Andy Shontz

CH601XL - Corvair

www.mykitlog.com/ashontz





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=113198#113198

skyguynca

Joined: 05 Jun 2006
Posts: 128

Posted: Wed May 16, 2007 4:12 pm Post subject: Wing sweep and recent crashes

Wow, this discussion has really gotten to comparing apples and oranges.

True we all need to wait and see what CH has to say after the new test.

I built a HD and will build another one but trying to compare it to the 

XL??? You can't two different airplanes. Personally I don't understand the 

rush to build a XL, the HD and HDS performance and durability is proven and 

the HD will fit in Sport Pilot. IT is a much simpler airplane. Oh and yes I 

do have plans for the HD (new set just purchased for my second build), HDS 

wing plans also and yes the XL plans.



One thing we might all remember, there have been several planes built by 

factories with lots of really smart and cutting edge aerodynamicists and 

engineers. Some of these planes were built really well and proven in public 

service over years....before they started coming apart due to unforseen 

problems. The Nimrod is just one example....it went into public and military 

service for a few years before the airframes started cracking and failing. 

There are several others too, google it. As far as dynamic with instability 

and flutter, google that too, there are several designs that had to be 

modified because the condition very rarely presented itself but when it did 

it was catastrophic. Trying to duplicate the condition was hard and almost 

impossible on the ground. Through careful flight testing, taking baby steps 

to completely simulate the conditions that caused the wing flutter it 

happened. It was studied and then the wing modified to keep the planes in 

service.



The whole point is people need to quit saying "the wing has a problem" 

because it might not. Also people need to quit saying "it is a proven design 

and hundreds are flying" because again, that is not true either. I did a FAA 

registraition search and it only comes up with 132 601XL's in the USA. Out 

of that only 89 carry a current airworthiness which means the others are not 

flying yet. I am not discounting ones in other countries but lets not 

stretch the truth about the number of actually flying ones. Also everyone 

keeps saying the pilots over stressed the plane either thru rough air faster 

than Va or Vne, no one knows that except the one who died in the plane.



Lets just wait and see what CH comes up with, also see if any more instances 

happen.



David Mikesell

23597 N. Hwy 99

Acampo, CA 95220

209-224-4485

skyguynca(at)skyguynca.com

www.skyguynca.com

robert.eli(at)comcast.net
Guest

Posted: Wed May 16, 2007 5:15 pm Post subject: Wing sweep and recent crashes

David and other interested folks,



Thanks for the reminder that flutter can be a very tough problem to 

diagnose. My earlier comments about the possibility of XL wing flutter were 

made prior to the announcement that Chris Heintz was going to do a complete 

review of the structural design of the XL. My original concern was that our 

many good friends on this Zenith list were overlooking the flutter 

possibility.  That is no longer an issue, given the many comments exchanged 

regarding this mode of failure over the past week. Now, I am confident that 

Chris will thoroughly revisit every aspect of the wing design to assure that 

the XL remains one of the best homebuilt designs available. I now will sign 

off on this topic and return to building.



Bob Eli



---

ashontz

Joined: 27 Dec 2006
Posts: 723

Posted: Thu May 17, 2007 3:49 am Post subject: Re: Wing sweep and recent crashes

Hey, I'll be behind a Corvair too.



What's cruise on the HDS with a Corvair?



 	  gboothe5(at)comcast.net wrote: 	
		  Whew!!! I'm glad to hear you say that! I truly hope that someday we can fly

wingtip to wingtip and compare the oil canning we each have in our

respective wings - you in an XL and me in an HDS. 



Of course, I'll be flying behind a Corvair, so I may have to throttle back a

little.... 



Gary Boothe 

Cool, CA 

601 HDSTD, WW Conversion 90% done, 

Tail done, wings done, working on c-section



.. I'm asking you, after all this intellectual discussion, after

 	  Quote: 	
		   looking at your web sight and all your careful work, are you going to

 install more ribs & beef up your spar?

 

 Gary Boothe 

 Cool, CA 

 601 HDSTD, WW Conversion 90% done, 

 Tail done, wings done, working on c-section

 

 --



	




I'll check with Zenith first as far as official analysis goes. I'm not

looking forward to extra work, but if I feel it needs it and there analysis

shows no negative effects I will do it. I don't think I'll mess with the

spar. I have .040 for spar cap angles as it is, the extrusion was just an

after thought. It wouldn't be too hard to install more ribs, making them

will be a pain in the ass because I hated making the forms. They're reall

time consuming.



--------

Andy Shontz

CH601XL - Corvair

www.mykitlog.com/ashontz





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=113198#113198

ashontz

Joined: 27 Dec 2006
Posts: 723

Posted: Thu May 17, 2007 3:54 am Post subject: Re: Wing sweep and recent crashes

Thank you! Thank you!



Yes, the possibility is there (just like in these other examples) that something could in fact be wrong with the XL wing that isn't showing up til now, and not only that, but it's something that doesn't present itself often under most conditions. Not only that, but there were mods made to these other planes that fixed the problem. That's all I was getting at and then just interpretting what I believe could be a problem, which I think may be slightly anemic twist resistance due to widely spaced ribs.



 	  skyguynca wrote: 	
		  Wow, this discussion has really gotten to comparing apples and oranges.

True we all need to wait and see what CH has to say after the new test.

I built a HD and will build another one but trying to compare it to the 

XL??? You can't two different airplanes. Personally I don't understand the 

rush to build a XL, the HD and HDS performance and durability is proven and 

the HD will fit in Sport Pilot. IT is a much simpler airplane. Oh and yes I 

do have plans for the HD (new set just purchased for my second build), HDS 

wing plans also and yes the XL plans.



One thing we might all remember, there have been several planes built by 

factories with lots of really smart and cutting edge aerodynamicists and 

engineers. Some of these planes were built really well and proven in public 

service over years....before they started coming apart due to unforseen 

problems. The Nimrod is just one example....it went into public and military 

service for a few years before the airframes started cracking and failing. 

There are several others too, google it. As far as dynamic with instability 

and flutter, google that too, there are several designs that had to be 

modified because the condition very rarely presented itself but when it did 

it was catastrophic. Trying to duplicate the condition was hard and almost 

impossible on the ground. Through careful flight testing, taking baby steps 

to completely simulate the conditions that caused the wing flutter it 

happened. It was studied and then the wing modified to keep the planes in 

service.



The whole point is people need to quit saying "the wing has a problem" 

because it might not. Also people need to quit saying "it is a proven design 

and hundreds are flying" because again, that is not true either. I did a FAA 

registraition search and it only comes up with 132 601XL's in the USA. Out 

of that only 89 carry a current airworthiness which means the others are not 

flying yet. I am not discounting ones in other countries but lets not 

stretch the truth about the number of actually flying ones. Also everyone 

keeps saying the pilots over stressed the plane either thru rough air faster 

than Va or Vne, no one knows that except the one who died in the plane.



Lets just wait and see what CH comes up with, also see if any more instances 

happen.



David Mikesell

23597 N. Hwy 99

Acampo, CA 95220

209-224-4485

skyguynca(at)skyguynca.com

www.skyguynca.com

ashontz

Joined: 27 Dec 2006
Posts: 723

Posted: Thu May 17, 2007 3:56 am Post subject: Re: Wing sweep and recent crashes

 	  robert.eli(at)comcast.net wrote: 	
		  David and other interested folks,



Thanks for the reminder that flutter can be a very tough problem to 

diagnose. My earlier comments about the possibility of XL wing flutter were 

made prior to the announcement that Chris Heintz was going to do a complete 

review of the structural design of the XL. My original concern was that our 

many good friends on this Zenith list were overlooking the flutter 

possibility.  That is no longer an issue, given the many comments exchanged 

regarding this mode of failure over the past week. Now, I am confident that 

Chris will thoroughly revisit every aspect of the wing design to assure that 

the XL remains one of the best homebuilt designs available. I now will sign 

off on this topic and return to building.



Bob Eli



--- 	




Seeing as how I'm working on the wings at the moment, I wonder if I should just put them aside til this is worked out and start building the fuselage.

bill_dom(at)yahoo.com
Guest

Posted: Thu May 17, 2007 4:35 am Post subject: Wing sweep and recent crashes

David Mikesell <skyguynca(at)skyguynca.com> wrote: 	  Quote: 	
		  I did a FAA 

registraition search and it only comes up with 132 601XL's in the USA. Out 

of that only 89 carry a current airworthiness which means the others are not 

flying yet. 	
How and where did you make the search. I'm using this page:

  

  http://registry.faa.gov/aircraftinquiry/acftref_inquiry.asp

  

  and I don't get more than 13.

  

  William Dominguez

  Zodiac 601XL Plans

  Miami, Florida

 [quote][b]

Gig Giacona

Joined: 10 Jan 2006
Posts: 1416
Location: El Dorado Arkansas USA

Posted: Thu May 17, 2007 5:22 am Post subject: Re: Wing sweep and recent crashes

Use that link and just put 601XL in the model name. Don't put anything in the Manufacturer Name  spot.

[quote="bill_dom(at)yahoo.com"]How and where did you make the search. I'm using this page:

  

  http://registry.faa.gov/aircraftinquiry/acftref_inquiry.asp

  

  and I don't get more than 13.

  

  William Dominguez

  Zodiac 601XL Plans

  Miami, Florida

  	  Quote: 	
		  [b]

_________________
W.R. "Gig" Giacona
601XL Under Construction
See my progress at www.peoamerica.net/N601WR

ashontz

Joined: 27 Dec 2006
Posts: 723

Posted: Thu May 17, 2007 5:36 am Post subject: Re: Wing sweep and recent crashes

Even more reason for more testing.



[quote="Gig Giacona"]Use that link and just put 601XL in the model name. Don't put anything in the Manufacturer Name  spot.

 	  bill_dom(at)yahoo.com wrote: 	
		  How and where did you make the search. I'm using this page:

  

  http://registry.faa.gov/aircraftinquiry/acftref_inquiry.asp

  

  and I don't get more than 13.

  

  William Dominguez

  Zodiac 601XL Plans

  Miami, Florida

  	  Quote: 	
		  [b]

cbaron66

Joined: 17 May 2007
Posts: 16

Posted: Thu May 17, 2007 6:17 am Post subject: Re: Wing sweep and recent crashes

I'm a long time lurker here, but this is my first post on this forum. I've been considering the 601XL for quite some time, but my only experiance with CH designs has been repairing a hail damaged HDS. I don't know the PC way to say this so please forgive my potential faux pas. I felt the HDS was wimpy enough(relative to RVs), but now there may be potential for the wings to fall off the XL? Man, this is not making my desicion on what kitplane to buy any simpler. If you guys feel the need to flame me go ahead.

skyguynca

Joined: 05 Jun 2006
Posts: 128

Posted: Thu May 17, 2007 6:24 am Post subject: Wing sweep and recent crashes

You have to make a variety of entries. Depending on  how they registered their airplane such as 601XL, 601-XL, XL601  ..etc

  

 You have the right link

  

 David Mikesell

23597 N. Hwy 99

Acampo, CA  95220

209-224-4485

skyguynca(at)skyguynca.com (skyguynca(at)skyguynca.com)

www.skyguynca.com

 [quote]   ---

Matt Ronics

Joined: 30 Apr 2007
Posts: 22

Posted: Thu May 17, 2007 6:34 am Post subject: Re: Wing sweep and recent crashes

 	  cbaron66 wrote: 	
		  I felt the HDS was wimpy enough(relative to RVs), but now there may be potential for the wings to fall off the XL? 	




Hasn't the RV-8 shed a few wings?

ashontz

Joined: 27 Dec 2006
Posts: 723

Posted: Thu May 17, 2007 6:42 am Post subject: Re: Wing sweep and recent crashes

 	  cbaron66 wrote: 	
		  I'm a long time lurker here, but this is my first post on this forum. I've been considering the 601XL for quite some time, but my only experiance with CH designs has been repairing a hail damaged HDS. I don't know the PC way to say this so please forgive my potential faux pas. I felt the HDS was wimpy enough(relative to RVs), but now there may be potential for the wings to fall off the XL? Man, this is not making my desicion on what kitplane to buy any simpler. If you guys feel the need to flame me go ahead. 	




What did you personally feel was wimpy about the HDS compared to a RV. I stopped down a local airport over the weekend just to compare. I also felt there was something anemic about the XL wing I'm building compared to a couple of the planes I looked at; one of them was an RV. In particular I didn't like the rib spacing on my XL. It was much wider than anything I saw down at the airport. The RVs rib spacing was half that if the XL. Granted, the RV has a shorter spar depth, but when I'm looking at slight oil canning on my lower wing skin, (and I'm being very careful about my building procedures) it makes me wonder. My top skin doesn't oil can because the skin has a more pronounced curve, but that strength is just an illusion in my opinion. The lower skin tells the story there. Under stress, the top skin would be subject to nearly the same oil-canning potential as the bottom.



It was just the feeling that you get when you see someone, and something just doesn't seem right about them but you can't put your finger on it and then you hear a month later they're in the hospital battling cancer. Even though you're not a doctor, you just knew something wasn't right with them.

gboothe5(at)comcast.net
Guest

Posted: Thu May 17, 2007 7:02 am Post subject: Wing sweep and recent crashes

No flames - just truth.



This is how things get blown WAY out of proportion. Somebody makes a

statement over and over, whether based on fact or not, and sooner or later

it becomes believable. 



I don't recall any crashes where the wings "fell off." Not with the XL, not

with the HD or the HDS. There may be some possibility of the pilot

unintentionally removing the wings in flight, due to over stressing, or

improper attachment, but the wings did not "fall off."



All of the 601's are plenty strong for what they were designed for:  a

simple to construct, inexpensive, lightweight A/C that is easy to fly.



If you want to go 180-200 and do aerobatics, then maybe you need a RV

(better check their crash records, too). Of course, you will spend 2-3 times

more $$ and take 3 times longer to build.



Everyone has to consider their own limitations. I chose the HDS because of

the 3 piece wing. My outboard sections are done and I can still lift and

move them by myself. That's important to me.



Gary Boothe 

Cool, CA 

601 HDSTD, WW Conversion 90% done, 

Tail done, wings done, working on c-section

--

cbaron66

Joined: 17 May 2007
Posts: 16

Posted: Thu May 17, 2007 7:38 am Post subject: Re: Wing sweep and recent crashes

 	  ashontz wrote: 	
		   	  cbaron66 wrote: 	
		  I'm a long time lurker here, but this is my first post on this forum. I've been considering the 601XL for quite some time, but my only experiance with CH designs has been repairing a hail damaged HDS. I don't know the PC way to say this so please forgive my potential faux pas. I felt the HDS was wimpy enough(relative to RVs), but now there may be potential for the wings to fall off the XL? Man, this is not making my desicion on what kitplane to buy any simpler. If you guys feel the need to flame me go ahead. 	




What did you personally feel was wimpy about the HDS compared to a RV. I stopped down a local airport over the weekend just to compare. I also felt there was something anemic about the XL wing I'm building compared to a couple of the planes I looked at; one of them was an RV. In particular I didn't like the rib spacing on my XL. It was much wider than anything I saw down at the airport. The RVs rib spacing was half that if the XL. Granted, the RV has a shorter spar depth, but when I'm looking at slight oil canning on my lower wing skin, (and I'm being very careful about my building procedures) it makes me wonder. My top skin doesn't oil can because the skin has a more pronounced curve, but that strength is just an illusion in my opinion. The lower skin tells the story there. Under stress, the top skin would be subject to nearly the same oil-canning potential as the bottom.



It was just the feeling that you get when you see someone, and something just doesn't seem right about them but you can't put your finger on it and then you hear a month later they're in the hospital battling cancer. Even though you're not a doctor, you just knew something wasn't right with them. 	




I guess anemic is as good as any way to describe it. I guess it just seems to me this plane(601XL) makes a good platform for a engine with less than 100hp and less than 160lbs installed weight. The problem seems to ME to be this is not how the airframe is being marketed-at least from my limited point of veiw. In an interesting side note, have you guys seen/heard, vans is once again redoing the RV12? apparently he's found it's not as easy as it first appears to design a one size fits all airplane that meets all the requirements of LSA, is easy to fly, is comfortable for crosscountry and isn't ugly as sin.

larry(at)macsmachine.com
Guest

Posted: Thu May 17, 2007 7:58 am Post subject: Wing sweep and recent crashes

The XL and the RV are apples and oranges.  The XL is a light plane and 

the RV is not.  The typical horsepower use for the

XL is 100 hp and the RV is nearer 150.  The time to scratch build an RV 

is near 8 years as it was 5 years for my HDS.

This doesn't make the XL less a plane, but it does point out that it 

flies slower with greater economy than a RV, costs considerably

less than a RV to build.  They're both great aircraft and both have had 

wing problems, probably due more to the way they were flown or built.  

The question is more of what you feel you want to spend over the long 

term in outlay $35K or $75K and can

you afford 7 to 9 gph at $4.50 or do you want to burn 3.5 to 4 gph at 

car gas prices occasionally.  The emphasis on speed

voids all these arguments and is probably the most costly and wasteful 

aspect of decision making.  Just think a little ahead of yourself.  The 

601 series is not compromised by being a light aircraft, but those who 

fly and build them can compromise that standard easier than the heavier 

aircraft.

Larry McFarland at www.macsmachine.com

do not archive

ashontz wrote:

 	  Quote: 	

 cbaron66 wrote:

> I'm a long time lurker here, but this is my first post on this forum. I've been considering the 601XL for quite some time, but my only experiance with CH designs has been repairing a hail damaged HDS. I don't know the PC way to say this so please forgive my potential faux pas. I felt the HDS was wimpy enough(relative to RVs), but now there may be potential for the wings to fall off the XL? Man, this is not making my desicion on what kitplane to buy any simpler. If you guys feel the need to flame me go ahead.

>     

 What did you personally feel was wimpy about the HDS compared to a RV. I stopped down a local airport over the weekend just to compare. I also felt there was something anemic about the XL wing I'm building compared to a couple of the planes I looked at; one of them was an RV. In particular I didn't like the rib spacing on my XL. It was much wider than anything I saw down at the airport. The RVs rib spacing was half that if the XL. Granted, the RV has a shorter spar depth, but when I'm looking at slight oil canning on my lower wing skin, (and I'm being very careful about my building procedures) it makes me wonder. My top skin doesn't oil can because the skin has a more pronounced curve, but that strength is just an illusion in my opinion. The lower skin tells the story there. Under stress, the top skin would be subject to nearly the same oil-canning potential as the bottom.

 --------

 Andy Shontz

 CH601XL - Corvair

 www.mykitlog.com/ashontz

 Read this topic online here:

 http://forums.matronics.com/viewtopic.php?p=113333#113333

cbaron66

Joined: 17 May 2007
Posts: 16

Posted: Thu May 17, 2007 8:36 am Post subject: Re: Wing sweep and recent crashes

 	  larry(at)macsmachine.com wrote: 	
		  The XL and the RV are apples and oranges.  The XL is a light plane and 

the RV is not.  The typical horsepower use for the

XL is 100 hp and the RV is nearer 150.  The time to scratch build an RV 

is near 8 years as it was 5 years for my HDS.

This doesn't make the XL less a plane, but it does point out that it 

flies slower with greater economy than a RV, costs considerably

less than a RV to build.  They're both great aircraft and both have had 

wing problems, probably due more to the way they were flown or built.  

The question is more of what you feel you want to spend over the long 

term in outlay $35K or $75K and can

you afford 7 to 9 gph at $4.50 or do you want to burn 3.5 to 4 gph at 

car gas prices occasionally.  The emphasis on speed

voids all these arguments and is probably the most costly and wasteful 

aspect of decision making.  Just think a little ahead of yourself.  The 

601 series is not compromised by being a light aircraft, but those who 

fly and build them can compromise that standard easier than the heavier 

aircraft.

Larry McFarland at www.macsmachine.com

do not archive

ashontz wrote:

 	  Quote: 	

 cbaron66 wrote:

> I'm a long time lurker here, but this is my first post on this forum. I've been considering the 601XL for quite some time, but my only experiance with CH designs has been repairing a hail damaged HDS. I don't know the PC way to say this so please forgive my potential faux pas. I felt the HDS was wimpy enough(relative to RVs), but now there may be potential for the wings to fall off the XL? Man, this is not making my desicion on what kitplane to buy any simpler. If you guys feel the need to flame me go ahead.

>     

 What did you personally feel was wimpy about the HDS compared to a RV. I stopped down a local airport over the weekend just to compare. I also felt there was something anemic about the XL wing I'm building compared to a couple of the planes I looked at; one of them was an RV. In particular I didn't like the rib spacing on my XL. It was much wider than anything I saw down at the airport. The RVs rib spacing was half that if the XL. Granted, the RV has a shorter spar depth, but when I'm looking at slight oil canning on my lower wing skin, (and I'm being very careful about my building procedures) it makes me wonder. My top skin doesn't oil can because the skin has a more pronounced curve, but that strength is just an illusion in my opinion. The lower skin tells the story there. Under stress, the top skin would be subject to nearly the same oil-canning potential as the bottom.

 --------

 Andy Shontz

 CH601XL - Corvair

 www.mykitlog.com/ashontz

 Read this topic online here:

 http://forums.matronics.com/viewtopic.php?p=113333#113333

Umm, You do know what an RV12 is don't you???????????????

p.mulwitz(at)worldnet.att
Guest

Posted: Thu May 17, 2007 9:19 am Post subject: Wing sweep and recent crashes

Hi Bruce,



A lot of us are concerned about the recent history of in-flight 

structural failures on 3 CH601XLs.  The latest news is that Chris is 

looking into this problem and may figure out what is happening.



I have a friend who has been building an RV-9A at about the same pace 

as my work on a 601XL.  The differences I can see include the solid 

rivets vs. pulled rivets, the different aluminum alloy, and the large 

engine cost differences.  The RV-9A also weighs more than the XL so 

it doesn't qualify as LSA.  All of these reasons lead me toward the XL.



I think the kit quality is better on the RV-9A.  It has all the match 

drilling done on a CNC punch, so alignment of parts is straight 

forward.  The ZAC kit is not so precisely done, so there is more 

"Art" in building the XL.



When I chose to build my XL there had not been any structural 

failures of note.  I don't know what I would do if I were starting a 

project today.  I don't think the XL is flimsy as you suggested in 

your question.  It uses heavier skin in a lot of places compared to 

earlier models like the HDS.  I think it has a bit higher performance 

and a bit more stability than the HDS since the fuselage is a foot longer.



Beyond all that, I would say your choice is a tough one because of 

the accident statistics building on the XL.  If it is a LSA compliant 

design you want, you might consider waiting for the RV-12, or you 

might just go ahead with an XL.



Good luck,



Paul

XL fuselage

At 07:17 AM 5/17/2007, you wrote:

 	  Quote: 	
		  



I'm a long time lurker here, but this is my first post on this 

forum. I've been considering the 601XL for quite some time, but my 

only experiance with CH designs has been repairing a hail damaged 

HDS. I don't know the PC way to say this so please forgive my 

potential faux pas. I felt the HDS was wimpy enough(relative to 

RVs), but now there may be potential for the wings to fall off the 

XL? Man, this is not making my desicion on what kitplane to buy any 

simpler. If you guys feel the need to flame me go ahead.





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=113321#113321

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