tube n rag vs spamcan

M

Mc Fly

Filing Flight Plan
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Sean
Does the old method of building a plane with a steel alloy frame and fabric offer any advantage/disadvantge over the newer aluminium /frame?
Does one type fare better in a crash (all things equal)?
 
I'm not sure the answer to this question, but I would be interested in hearing peoples thoughts/exp. with rag & tube.
 
Sean, are you considering building one or owning one? The crash worthiness would depend on which specific aircraft you are considering. As you may know, there are aircraft with steel tube frames and aluminum skin. -- Mike
 
Mike Schneider said:
Sean, are you considering building one or owning one? The crash worthiness would depend on which specific aircraft you are considering. As you may know, there are aircraft with steel tube frames and aluminum skin. -- Mike
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Certified planes only. Let's say a c-172 and a Supercub.
 
Mc Fly said:
Certified planes only. Let's say a c-172 and a Supercub.
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IMHO It's an apples to oranges comparison.
Having recently read a book on aircraft crash worthiness, I know a little about the subject, but I'm certainly not an expert. A whole bunch of people on the boards probably know a whole lot more than I do.

Aircraft crashes involve three principal dangers to occupants: Fire, impact/deaccelaration forces and injuries caused by occupants being crushed by aircraft structure.
The steel tube frame work is probably stronger in an accident than the semi monoque structure of most spam cans, and this can help to protect occupants from being crushed by aircraft structure. In addition a steel tube frame work may have seats bolted onto the framework directly, and properly restrained occupants can usually stand quite a bit of instanious deaccelaration forces. A structure which is designed to deform in areas which don't contain people can actually absorb some of the impact forces, and prevent injuries to occupants. Still, a cabin's crushworthiness becomes very important in the milliseconds following an initial impact.
A steel tube can create a solid cage around the occupants and prevent injuries that would otherwise occur to occupants of a semimonique structure. The fabric covering probably doesn't change too much, and any object which is strong enough to impale occupants will probably rip through light aluminium skin with ablomb.

Super cubs can be dangeous in an accident because of the fire risk of their tanks which are (I think) both above the lap of the pilot and above the heads of both occupants. I believe there have been a few accidents where the occupants have been burned by fuel from these tanks.

Basically (assuming the acft is equipped with shoulder belts, which all should be!) almost all airplanes are strong enough to survive smallish accidents (overruns at mild speeds into relatively obstruction-free terrain.) The merits of one design over another only give you slightly better chances of survival in the types of accidents which usually kill everybody anyways. These are the ones which pilot training can avoid, i.e. stall/spin, overstressing the airframe, and CFIT.


IMHO the safest airplane is probably the Mooney 20 series, which have an aluminium skin built over a steel cage.

Everybody, please feel free to tell me where you think my understanding is wrong about the above.
 
super cub gas is in the wings. you may be thinking J3 with header tank only? gas sits between front seat passenger and engine. pilot sits in back.
 
Doesn't a super cub have a header tank?

I think that the pilot in supercub sits in the front, since the CG is farther back because of those wing tanks.
 
supercub pilot does sit in front. only two gas tanks, one in each wing.
 
tonycondon said:
supercub pilot does sit in front. only two gas tanks, one in each wing.
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I think it depends on the year of the Super Cub. I think the early ones were J-3 with big engine.
 
im not sure, there really isnt a lot in common between them except the name. bigger fuselage, different wing (i think) beefier everything.

I think the J5s and PA11/12s may be more along your lines of thinking
 
A couple other important considerations WRT crashes is that 1) the fabric won't do nearly as much to block branches etc if you go through trees, increasing your chance of being shishkabob. On the flip side, you can rip through fabric much easier than through aluminum if the door(s) are blocked or deformed.

Fabric is lighter. Metal survives outside better.

So it's really a question of picking your poison. I have owned two metal airplanes and two fabric airplanes. For what it's worth, my next one likely will be metal.
 
PA-12 has fuel in the wings only.
 
Greg Bockelman said:
Unless you find a good Bamboo Bomber for your twin! :D
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yeah, that's it!!

Actually, I was going to rent the local FBO's Seneca while I looked at twins -- and kept playing with my Pitts. But now they've gone and removed it from the list of airplanes that can be rented. It's just for instruction now. So that will force my hand. I found a couple mid-60s B55s that look decent on paper, but until/unless I dispose of the Pitts, I'm stuck. And I really want to keep the Pitts. Dilemmas, dilemmas ...
 
Ken Ibold said:
And I really want to keep the Pitts. Dilemmas, dilemmas ...
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I want a George Jetson airplane. It's a nice aerobatic tandem taildragger, then push that button, and it's a sleek and efficient family hauler. Yeah, right.

I need to go back to school, get an MBA, and make more money. :yes:
 
I friend of mine survived this..good old rag and tube
 

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Ken Ibold said:
A couple other important considerations WRT crashes is that 1) the fabric won't do nearly as much to block branches etc if you go through trees, increasing your chance of being shishkabob. On the flip side, you can rip through fabric much easier than through aluminum if the door(s) are blocked or deformed.

Fabric is lighter. Metal survives outside better.

So it's really a question of picking your poison. I have owned two metal airplanes and two fabric airplanes. For what it's worth, my next one likely will be metal.
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The super cub is the work horse of Alaska, they set out doors in all the bad weather Alaska can give, and they do better that the spam cans when it comes to Hail, sun, and any thing else you can think of..

REMEMBER, we are no longer thinking dope over cotton, we are talking about todays modern Ceconite, and several urathane paint systems, even the old stitz systems are approching 30 years old and still doing the job.

Airtech and AFS are much better systems than Stitz in UV blocking, and will remain flexable from now on.

so the OWT that fabric systems are short lifed, are just that, OWTs

and as far as the branches breaking thru the fabric, that must be a imagined hazard, because the fabric is covering a very good steel structure, and if you ever see a super cub with the fabric off you will see how wrong you are.

For every ones facts, the PA 18 is not much like the J3, other than it has 2 wings and a tail that looks alike. the new 180 horse Supercub by Cub Crafters is certified to 2400 pounds gross weight, float fittings, and extended baggage, squared off instrument panel with GPS, and electric start.

The red and white super cub is what the yellow one looks like today,.
 

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Everything else aside, fabric planes just have a bit more class than a spam can. IMHO. A 172 is just a dime a dozen 172, but folks always wanna chat when the Stinson pulls up. The ohh-ahh factor is kinda cool.
 
i thought that was the best part about doing fabric work! hows it coming along diana?
 
Diana said:
Well, after again spending two solid days working on restoring my fabric airplane, I'm not sure anymore. Maybe it's the hours spent inhaling all those fumes from the chemicals, including the nitrate and butyrate dope and glue and thinner and who knows what else was in all those containers.......
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I told ya, do it the easy way..

http://www.stewartshangar21.aero/AFS.htm

It don't stink. ships with out haz mat charges,

and the first 3 coats go on with a foam brush.

see my page cecofil demo

http://www.whidbey.com/fairchild-nc19143
 
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Ken Ibold said:
the fabric won't do nearly as much to block branches etc if you go through trees, increasing your chance of being shishkabob.
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I used to LOVE shishkabob...until I read this! :eek: :D
 
Diana said:
I used to LOVE shishkabob...until I read this! :eek: :D
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Kidding aside, I wouldn't put much faith in an aluminum skin to resist punctures from tree branches and sign posts either so don't go trading that Citabria in for a metal bird. Fortunately (IMO) the likeihood of a serious injury from a tree branch in the cockpit is fairly low compared to many other serious hazards in any plane, fabric or spamcan.
 
tonycondon said:
hows it coming along diana?
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Tony, thanks for asking. If I should ever mention that I am even *thinking* of getting another fabric airplane, just take me out back and shoot me!!!!!
 
oh ok! so when the glider needs recovered I can just call you? :rofl:
 
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