Zenith Aircraft

[Curt Fennell]

Has anyone built one of the Zenith aircraft or dealt with them on a
regular basis? I am curious to know if they are good with builder
support.

TIA,
Curt
--
Curt Fennell, curt at phins DOT com

[Gig 601XL Builder]

I'm building a 601XL now. They have been nothing but helpful and have
answered every question I've had.



"Curt Fennell" > wrote in message
...
> Has anyone built one of the Zenith aircraft or dealt with them on a
> regular basis? I am curious to know if they are good with builder
> support.
>
> TIA,
> Curt
> --
> Curt Fennell, curt at phins DOT com

[cavelamb]

Gig 601XL Builder wrote:
> I'm building a 601XL now. They have been nothing but helpful and have
> answered every question I've had.
>
>

And that's pretty much what all the builders I've met have said too.

Good airplane too!

Richard

[stol]

I " LOVE" my Zenith 801.. The folks at Zenith Aircraft are the best
people to do business with. They did kinda shake their heads when
mentioned I was going to install a V-8 aluminum Ford in my plane, but
now that it hasn't broken in half or killed me yet they have givin me
nothing but praise. I can tell ya the design CAN handle more then
double the suggested HP. That speaks volumes for Chris Heinz's
designs....

Ben
www.haaspowerair.com

Curt Fennell wrote:
> Has anyone built one of the Zenith aircraft or dealt with them on a
> regular basis? I am curious to know if they are good with builder
> support.
>
> TIA,
> Curt
> --
> Curt Fennell, curt at phins DOT com

[Richard Riley]

Curt Fennell wrote:
> Has anyone built one of the Zenith aircraft or dealt with them on a
> regular basis? I am curious to know if they are good with builder
> support.
>
> TIA,
> Curt
> --
> Curt Fennell, curt at phins DOT com

They have a very good reputation these days. There was a bad spell, a
long time ago, when they were doing a kitted version of the CriCri (bad
enough that you can't buy Cri-Cri plans if you're American) but they
seem stable and supportive now.

[Gig 601XL Builder]

"Richard Riley" > wrote in message
oups.com...
>
> Curt Fennell wrote:
>> Has anyone built one of the Zenith aircraft or dealt with them on a
>> regular basis? I am curious to know if they are good with builder
>> support.
>>
>> TIA,
>> Curt
>> --
>> Curt Fennell, curt at phins DOT com
>
> They have a very good reputation these days. There was a bad spell, a
> long time ago, when they were doing a kitted version of the CriCri (bad
> enough that you can't buy Cri-Cri plans if you're American) but they
> seem stable and supportive now.
>

Zenith did a Cri-Cri? When was that? Any photos out there?

[Richard Riley]

Gig 601XL Builder wrote:

> Zenith did a Cri-Cri? When was that? Any photos out there?

A very long time ago - like, in the 70's. As I understand it there
were a lot of materials substitution that proved to be inadequate.
Here are a couple of quotes from the cri-cri mailing list.


> The Laison tube runs across the fuselage under the knees
> of the pilot. It connects the movement of the two flaperons. It also
> mounts the bellcranks for the flaperon "aileron" action, and also rotates
> to make the "flap" action.
>
> The Zenair tube is made from thin steel tube, maybe 19mm diam. It is
> flexible and acts like a tuning fork. Any induced deflection of one
> flaperon is amplified into the other flaperon, and you get a flutter that
> continues until some connection between the flaperons breaks OR until
> something ELSE on the airplane breaks and it becomes uncontrollable...
> There have been 6 known cases of Cricket flutter; the one fatality was
> Jim Harper.
>
> The Colomban tube is 32mm, and made of stiff aluminum.
> As you know, most people think of aluminum just for it's lightness, but
> aircraft designers use the fact that it is STIFF.
> The Columban tube is too stiff to transmit any induced deflection from
> one flaperon to the other.
>
> Also please tell your friend about the elevator actuator connection. The
> Zenair modification (307.07m) is just 2 little pieces of bent aluminum.
> They are NOT strong enough. Use the machined fitting as described in the
> original plans !!!!!!!!!!!!!
>
> The same is true for all other parts of the control system.
> Cheap substitutes of parts pivoting directly on bolts instead of using
> the ball joints ("heim joints") called for in the blueprint, etc., etc.
> ALWAYS FOLLOW THE ORIGINAL PLANS...


and this

>Hi all'
>I am an IA and I have long been excited about the CriCri.
>I purchased plans from Zenair in 1996 and was told by them that
>I got the last set. My question is about the Zenair plans.Are they the
>same plans as the desingers? I believe I read in the archives that they
>are the same and you should build from them and ignore Heintz's
>modifications. Thanks for your help Rocky Lennon

Dear Rocky,
You got it right, there were no "Zenair" plans, they merely
went to the local blueprint shop and ran off copies of the
"desingers" original.

Follow those plans and you will be OK.
There are 2 changes Michel approves of (but does not get involved in).

1. Go to a modern mechanical disc brake such as found on a go-kart.

2. The JPX engine is inadequate, and it looks like good progress
is being made in adapting 3W engines. See the earlier posts.

A request for you:
What is the Zenair serial # on your plans???
If they are the last set, that will tell us how many
plans Heintz stole from Michel without paying royalties...

Have fun...David

[Jim Carriere]

Richard Riley wrote:
> Here are a couple of quotes from the cri-cri mailing list.
>
>> The Zenair tube is made from thin steel tube, maybe 19mm diam. It is
>> flexible and acts like a tuning fork. Any induced deflection of one
>> flaperon is amplified into the other flaperon, and you get a flutter that
>> continues until some connection between the flaperons breaks OR until
>> something ELSE on the airplane breaks and it becomes uncontrollable...
<<cut>>
>>
>> The Columban tube is too stiff to transmit any induced deflection from
>> one flaperon to the other.

Nitpick (I realize it is not your statement, Richard, but from the
mailing list) about flutter:

A technically more correct statement about the Columban tube is its
increased stiffness eliminates the flutter tendency of the Zenair tube.


Anyway...

A layman's explanation is the larger tube still vibrates, but its
resonant frequency is much higher. Since the airflow over the flaperons
is the source of the vibration, you would have to fly much faster before
the vibrations reach that higher frequency (and the flaperons
destructively "sing" to each other through the tube, and the tube
"sings" along, or resonates).

Both tubes transmit vibrations, just not particularly well when the
vibrations are not at their own resonant frequency (think of one tube
like an "A" tuning fork and the other like a "C"). In most flight
regimes it is irrelevant. The problem is they respond a little too well
to their resonant frequency.

Flutter- a really really complicated branch of aerodynamics. :)

[Ken Finney]

"Curt Fennell" > wrote in message
...
> Has anyone built one of the Zenith aircraft or dealt with them on a
> regular basis? I am curious to know if they are good with builder
> support.
>
> TIA,
> Curt
>

I've heard nothing but good things about their customer support, once you
are a customer. I've been to some shows where they were fairly rude to
perspective customers, but once you write them a check, they bend over
backwards to help you.

[Gig 601XL Builder]

"Ken Finney" > wrote in message
...
>
> "Curt Fennell" > wrote in message
> ...
>> Has anyone built one of the Zenith aircraft or dealt with them on a
>> regular basis? I am curious to know if they are good with builder
>> support.
>>
>> TIA,
>> Curt
>>
>
> I've heard nothing but good things about their customer support, once you
> are a customer. I've been to some shows where they were fairly rude to
> perspective customers, but once you write them a check, they bend over
> backwards to help you.
>
>
>

I noticed it to and I think it is specifically one person. I really don't
think it is rudeness. I think it is just personal mannerisms. The reason it
seems like they get nicer after they get a check is because by that time you
have gotten use to it and realize that it isn't rudeness.

I'm from the South. People, especially in that sort of business, are
generally almost overly friendly. It's quite a shock to deal with one that
isn't.

[Ken Finney]

"Gig 601XL Builder" <wrDOTgiaconaATcox.net> wrote in message
...
>
> "Ken Finney" > wrote in message
> ...
>>
>> "Curt Fennell" > wrote in message
>> ...
>>> Has anyone built one of the Zenith aircraft or dealt with them on a
>>> regular basis? I am curious to know if they are good with builder
>>> support.
>>>
>>> TIA,
>>> Curt
>>>
>>
>> I've heard nothing but good things about their customer support, once you
>> are a customer. I've been to some shows where they were fairly rude to
>> perspective customers, but once you write them a check, they bend over
>> backwards to help you.
>>
>>
>>
>
> I noticed it to and I think it is specifically one person. I really don't
> think it is rudeness. I think it is just personal mannerisms. The reason
> it seems like they get nicer after they get a check is because by that
> time you have gotten use to it and realize that it isn't rudeness.
>
> I'm from the South. People, especially in that sort of business, are
> generally almost overly friendly. It's quite a shock to deal with one that
> isn't.

Plus, I'd rather they act the way they do, instead of being rude AFTER they
get paid! ;^)

[Richard Riley]

Stew Hicks wrote:
> Who says Chris Heintz stole the Cri-Cri plans? I happened to ride to dinner
> with Chris and Michel at Oshkosh during the show where they made their deal
> on the Cri-Cri. I know nothing of their agreement but in my dealings with
> Chris I have never found him anything but honest and very helpful.

I have no direct knowledge of the situation. The CriCri mailing list
seems to have a strong opinion of Mr. Heintz. I just posted some
quotes from there.

http://groups.yahoo.com/group/CriCri/msearch?query=heintz&charset=windows-1252