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raiki said:

If you look at the kits for the Long-EZ and the Cozy from Wicks and Aircraft Spruce they are selling 3/4". This is why I used it. I am not sure if RAF used different foam back in the day or if they rounded up 0.75".

Ahh! That explains that.

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Disregard anything to do with Section IV at this stage. The landing brake will be included in the plans (like the Cozy) and will not require a Section IV. This will be added when that chapter is written so I can properly reference it.

The part I want to emphasize is that IV is not the same as VI. It *looks* like you've missed that fact twice now.

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If you mean that there is only one shaded picture of the front seatback with all the others simple line drawings, for example, I did this for clarity. I think line drawings are easier on the eye for step by step guidelines. I intend only for there to be one 3D "rendered" image of MOST bulkheads.

I think I'll prototype a different layout when we can share sources... I think it'll be clearer with consistent colour.

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I didn't think that was neccessary because it is obvious the general shape is symetrical. I will add it to make you feel better.

In case its not obvious: when writing documentation, I'm of the opinion that you should insult the intelligence of the reader in the interests of being precise.

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Again thanks for the input and remember this is the first draft of a project that may or may not happen. We are currently at the feasibility stage.

NP. I figure the better even the demo docs are, the better the chances of whatever we might consider success.

Wolf: I am not positive, but I *THINK* I read in Bill James' blog about installing them.

I really like what you've done to the plans! They look very clean. (not that the RAF plans were messy exactly...)

I have a few suggestions&corrections:

1) Label all images

2) Explicitly refer to the images with phrases like "See figure 1".

- As it is, users of the plans have to play connect the dots. Its not super difficult to do, but why play the game at all if it can be avoided?

3) why did you change "0.8in thick" to "3/4in thick" in step 1?

4) The first step wants you to make 2 0.7in tapers, but the dimension of the taper is mentioned only w.r.t. the second taper. I would include it with the first for clarity.

5) There are some differences in the labeling of the images. The Long-EZ plans say "see section VI" w.r.t. the right hole cut in the front seatback. Your Open-EZ plans say "see section IV".

6) The Long-EZ plans show, in the drawings, that the back of the front seatback has a single ply BID at 45degrees. the Open-EZ plans have dropped the "at 45 degrees" from the drawings, so its now unstated...

7) step2, there is no e in "strong". There is also only one d in "sanding"

8) At this point, it occurs to me to ask: why are you not consistently using the blue for the foam in all the drawings so far?

9) The Long-EZ plans' drawing showing that the rear seatback is 18.7in at the top and 20.6 at the bottom also clearly shows that both sides narrow evenly (ie: its an "isosceles trapezoid" if wikipedia is to be believed) because it has that little extra 0.95in dimension. Your Open-EZ plans lack that dimension.

10) I guess its not strictly necessary, but since the forward bulkheads have full-size templates... might it be easier on the builder to make full-size templates for the seatbacks too?

... I'll look at steps 3 and 4 later.

For varying definitions of "in the works". Also, the model they have in the office is, IMO, butt ugly.

Its my understanding (I'm still reading the TERF plans) that ALL parts are detailed in the plans, but that RAF sold the harder to manufacture parts, and/or recommended sources for them. If you had the skill sets, you didn't need to buy any parts beyond glass, epoxy, engine, and avionics.

where are all the velocity kits?

looking for one with gull wing doors only.

Please pm or email if you have one.

go to tvbf.org and read through the archives for April and May of this year. Many planes (built and not-built) have gone up for sale there recently.

You could probably use someone's facilities. Andy Millin (a velocity builder) did his postcure at what looks like a body-shop, although he says it was in there with other airplanes. http://www.kal-soft.com/velocity/weblog.asp?pic=137

I would think that you could probably rent time from a car body shop that has the facilities, assuming the temps are right.

I particularly like the fact that they're going to go from concept renderings to certification in under 18 months, according to the article on gizmag (http://www.gizmag.com/falx-to-debut-hybrid-electric-tilt-rotor-aircraft-with-inbuilt-solar-c/9234/)

Oooh! a perpetual motion flying machine!!! (http://www.gizmag.com/go/3060/)

You may be thinking of another event, Waiter, but your comments made me think of the velocity deep stall testing.

You can read about the velocity deep stall problems on www.velocityxl.com. He's re-arranged his site recently, so some of the links are dead, but I'm sure its all still there somewhere.

Anyhow, as I recall, the early velocities could go into a stable deep stall. velocity got a test pilot to reproduce the phenomenon, and then he tried to figure out how to get the plane out of it. At some point, he gave up, and planned to exit the plane. he didn't lean out to adjust CG (and it didn't make a difference anyhow). When he opened the door, he decided the descent looked slow and stable enough, and decided to ride it down. The plane made a water... landing... with little damage and the pilot was unharmed.

There's a little bit about it in CP76.

None-the-less, the relevant point is right: the pilot opened the door in flight, and managed to close it again, too, if I recall correctly.

Please don't degrade yourself anymore, and try to get started on your project.

My Canada includes Canards.

It has been purchased by RRL. I suggest you check out the most recent email from Ken Baker on the Velocity builders list (. He talks a bit about it. If you take it all at face value, this sounds pretty good for velocity. I'm optimistic.

Wouldn't the rudder placement reduce yaw control? I would expect the rudders at the wingtips would be further from the CG and thus have more leverage.

When I went to the Velocity factory and flew in the XL, the factory pilot said that they don't recommend that you slip. If I recall correctly, he said that the plane doesn't have a lot of aileron travel... Nonetheless, the plane felt like it slipped fine to me, and he didn't say it was never OK. Also, I'm almost certainly mangling the explanation he gave me; there was alot going on, and I was having a good time in my first flight in a canard. I was a little distracted.

I certainly hope velocity doesn't waste time on lawsuits. They're expensive, and would just distract them from what they're supposed to be doing. They've also got a decade or so headstart on phoenix... A good reputation is worth more than so-called intellectual property on a wing design that was arguably ripped off of Burt Rutan anyhow.

Are you concerned about the difference in airspeed and fuel economy? Also, I don't think the SERG can carry the same weight load.

So the SERG has some minuses. It may have some pluses too though. There are reasons you may prefer to buy a kit from a company (ie: the support that company gives you. Some perceive it to be a shorter build too).

But its all fairly debateable. I don't think the available data tends to back the idea that the kit plane is faster to build, and the support you can get from mailing lists and forums like this one may, to you be worth more than the factory's support.

Which means it mostly boils down to what you value most, and can you afford the price difference. Opinions of people like a spouse or family might be important too. You may not be able to get your would-be passengers into one or the other plane.

yeah, that's the thing. Every time I read about jeffco, its in the context of a velocity, not a cozy. It comes to mind because the velocity builders seem to be using it because its more resistant to other fuels than the epoxies being used, or at least, that's what I understand to be the reason.

Do cozy builders typically coat their tanks with jeffco?

Wsa not aware of the practice. I see. Too bad they don't just repair and get it back in the air. Bill Oertell has quite the effort required on his.

My impression is that its not about what's repairable. It about what the wife will sit in ever again.

Check with the factory about this. The "problem" with the velocity is that the materials used in the fuselage are not the same as what you're using elsewhere, and it has a higher temperature tolerance. As a result, what is not acceptable for the wings, canard, and a LEZ or Cozy, *MAY* be acceptable for the fuselage. I think they're discouraging dark colours, but they're not insisting on white.

I'm pretty sure that I read that Rutan talked about this in one of the Canard Pushers. IIRC, I didn't read the article directly, but instead read Bill James' summary of it in his blog (EZ Chronicles. Always a good read!). I'll look for the article tonight.

I am not an owner, but I did sit in an SE at the factory. There is some space for bags behind the back seat, but very little. i would say that if, as a family, you pack very light, you could manage a weekend trip in the SE. The XL is much more realistic for carrying 4 people and their bags though. With kids in the back, you can move the seats forward pretty far, leaving enough space behind the back seat for alot of bags, *AND* still leaving the kids with leg room.

Before you buy though, I strongly suggest you go and sit in one.

I've been thinking about how much it costs to own and operate a plane. I was hoping I could get some feedback on what I think it is, so far.

- I'm running on the assumption I fly about 100 hours a year.

- I've read that a good rule of thumb is that every hour in the air costs about 15 dollars in maintenance.

- going by a recent ad for hangar space at CYKF, hangars cost 600/month

- I was told insurance will cost 6000 a year. (however, I've seen ~1000 in the forums here. I dunno if that's CDN vs US, or too much hull insurance...)

- Fuel burn is about 10 gallons per hour

- fuel costs aboout $4.50/gallon

So in total, that's 7200 for hangar, 1500 for maintenance, 4500 in fuel, and 6000 for insurance, or 19,200 per year. Does that sound about right? Am I forgetting anything?

I heard a rumor yesterday that innodyn is under new management, that the new owner is less interested in generating hype than in getting the engine into production, and that if he goes to a show this year, its to announce full production and immediate availability. Oh! And he might have deeper pockets.

I just wish I could believe it all.

Would a ducted prop make a difference here?

http://www.bridgingworlds.com/kpae/20020209_sideview.jpg

I think you mean 2 UNI. The lower skins are 2 UNI and the top skins are 3 UNI (at least the COZY is - I believe the LE is the same, having looked at the LE plans a couple of weeks ago). The third layer of UNI on the top is spanwise, and used to prevent buckling, since the top skin is in compression, spanwise.

yes, now that you point it out, I realize I was (a) remembering wrong and (b) only reading about the bottom skins.

Thanks for the answers Marc. Helpfull as always!

Tyson: thanks for the link. Some good bits in there.

ok, so I was at the Velocity factory a week ago, and they said that for the fast-build wings, they used triax, which, I understand, is fibreglass cloth with fibres arranged in 3 axes (axiis? however you pluralize axis). They said that, that way, they could make a lighter wing with fewer layers in the layup...

OK, but when I got home, I looked at the TERF CD, and the LongEZ plans call for only 2 layers of BID (if I`m not overlooking anything) as opposed to the 3 (or 6) layers of UNI I was kinda expecting, which would be more comparable to one layer of triax, I think.

I`m left wondering some things... Do Cozy builders ever use triax? Is there a reason why Nat wouldn`t have called for its use where appropriate? Are the wing skins on the cozy the same as on the LongEZ? Are 2 layers of UNI, appropriately oriented, comparable in strength but not weight to one layer of BID?

I don`t presume that velocity is selling an unsafe `fastbuild` wing, but I`m left wondering what the real tradeoffs are, beyond time and price... But thats for an email to them, not you...

I`m currently flying DiamondAir DA20-A1s, which are powered by a Rotax 912 with a CS prop. The flightschool I`m at has had good experiences with the plane, its been pretty reliable for them AFAIK, but it doesn`t have the best climb performance. The Cessna 172s outclimb them quite handily. The varieze is about 200kg lighter than a katana, and has what I presume is a lower drag shape, but my knee-jerk reaction is to assume you might be a little unhappy with climb rates and maybe the top speed too. Some of the oldest katanas in the school`s fleet were having some engine cooling problems over the summer, and Diamond was working with the school to resolve those problems. It was my understanding that the problem was only in some earlier A1s, not all A1s, and I am not clear if they did any ducting or engine changes, all I`m certain of was that they changed the coolant used, and that for a month, my instructor was taking detailed notes about engine temperature and performance as well as coaching me through stalls, spins and spiral dives.