Pressurized Cozy?

[Rui]

Ok, well I'm probably inviting the wrath of the "build it to the plans" people, but has anyone thought of what it would take to make the Cozy a pressurized plane? I live near the Rocky mountains and one of the nice things that I would be able to do with a Cozy is fly out to Vancouver Island and enjoy SCUBA diving (one of my other hobbies) over a long weekend.

 

I suspect it would involve many changes (canopy, firewall, access hatches) so I doubt it would be easy/cheap to do, but I'd like to have and idea of what it would take.

 

I realize that there are oxygen systems out there and that is probably what I'll end up doing, but while I'm at the planning stage I'd like to look at all possibilities.

[dust]

probably $100,000 and 5 years

[Joe Cygan]

Rui,

That sure would be an ambitious project.Besides a source of compressed air,pressure regulator,outflow valve,pressure relief valves,negative relief valves,dump valves,control valves,heat/air source,pressure bulk heads,door seals, and a fuselage which could withstand at least 8 psi of pressure.Who wants to go first?

 

Joe Cygan

CozyMKIV #1022

[John Slade]

Rui,

My plane is getting air conditioning. The total extra weight is 33lbs. With some difficulty I've managed to find homes for all the parts without giving up any passenger space. As for the weight - I figure I've got 50 -60 lb head start on a lot of builders.

 

Pressurization is a huge step beyond AC. Sealing all the holes would be a tough job, and controls would be life critical. Pressure isnt something you want to have let go at altitude (remember that Lear).

 

Down here in South Florida there's a fairly busy portable OX business. I figure I'll pick up a used system from one of the locals.

[Rui]

Thanks for the replies. I suspected that it wouldn't be something for an total novice to airplane manufacture like me to tackle. I guess I just needed reassurance that it would be a foolish thing to try.

 

John, loooking at the prices of new portable oxygen systems it doesn't seem like a huge expense ($500-$1000 as I remember). Is the price difference on the used systems really that great? And why is it used?? Are the cylinders past the the date stamped on them?

 

Unless of course you mean the oxygen systems that old folks buy and become available when they kick off? The I can see where it would make sense...

[Jim Sower]

I personally can't imagine why anyone would feel a NEED for pressurization below 25,000 ft. Nor can I imagine why anyone would want to fly a Cozy in the Flight Levels at all. Oxygen bottles are light, cheap and abundant.

Ten cent tail wagging the forty dollar dog again?? .... Jim S.

[Rui]

Now that you mention dogs.... that's actually a consideration. We have two dogs which we take with us on driving vacations and camping and such. So when we go by plane it would be nice to take them as well. Obviously you can't put oxygen masks or canulla on dogs so pressurization would be nice, but as everyone seems to agree not feasible for the Cozy.

 

I guess we'll have thread the mountain passes when we take the dogs...

[John Slade]

Dogs! Dogs! Don't talk to me about dogs.

We currently have 11 of them.

See http://kgarden.com/dogs

 

PS - I'm not really upset. They have names like:

"nav", "com", "EFIS", "carpet" and "couch"

[Jim Sower]

The dogs would probably survive just fine with no O2 or pressure if you stayed below the CCA. They don't have demanding crew responsibilities, and the higher you go, the better behaved they get

Just a theory .... Jim S.

[Frank]

As a novice, I'm not sure if this has any relevance whatsoever :-)

 

Ever heard of Wingco? They used to make prefab parts for the Velocity and they are currently working on an aircraft called the 'Atlantica'. Its not a canard but its a pusher BWB design and it has a pressurised cabin. It falls in the same price bracket as the velocity ($30-50k give or take).

 

A prototype hasnt flown yet but all the taxi tests have been completed so it wont be long. www.wingco.com (I think)

[John Slade]

Yes, the Atlantica is a very cool looking airplane. I particularly like the wide bodied cockpit, but there are lots of other interesting features. Definately worth watching....

[Rui]

They seem to be pretty sure of themselves, but I worry about the thing flying correctly. I have heard that the Stealth bomber takes quite a bit of computer assisted coordination to acheive stable flight. This plane looks very similar in shape so I worry about its actual flight characteristics.

 

I also noticed that the description of the LOM engine says that the integrated supercharger can be used for cabin pressurization to 2 PSI. This is also the claimed pressurization level of the Atlantica, but there is nothing saying that Wingco is doing this.... Has anybody ever tried an LOM engine in a Cozy?

 

Anyway it does look like a cool plane, but Nat's advice against kits that may go away if the company fails comes to mind everytime I look at kitplanes. I think the only kitplane I'd be comfortable getting is an RV, but they don't meet my requirements...

[unick3]

If you plan to fly very high, you really need to turbo charge the engine otherwise you will have very little power. A normal O2 system is only good up to 24k then you need a presurized O2 system (to force the O2 into your blood). I cant see any need to fly greater than 20k feet anyway.

 

If you buy a system get a Mountain High system with the electronic flow system. It saves a tremendous amount of O2 from being wasted. I have a small bottle and it will last for at least 8 hrs. Then I bring it home and refill it from my BIG O2 tank. It cost about $.50 per filling....

[Dan Tomlinson]

What about on-board oxygen generation? The "medical" oxygen generators (actually concentrators) use electricity, cool air, and internal "catalyst filters" to effectively filter the nitrogen from normal air, giving out continuous medical O2, at about 6PSI, 5 litres/minute.

 

Would this, and econoMizer canula's be considered sufficient and reliable enough for use in a Cozy?

Certainly having an unlimited supply without needing to refill at various locations enroute can only be a good thing!

 

/dan

[Jim Sower]

I would guess that at $0.50 per refill, and a small portable bottle should last one max leg at least, that would be much preferable over an O2 generator. O2 generator is a sophisticated mechanism that involves capital expenditure and requires hi-$ maintenance. An O2 bottle is a freaking BOTTLE. One big one, several little ones. Refill big one for pocket change at local welding supply store. Simple, cheap, reliable, all I would evere need.

As for pressurization, 2 psi = 288 psf = 2592 lb per sq yd!!!

Just a theory .... Jim S.