Kitfox aluminum ribs

[Ls1swap]

I understand the fabric covering for weight and flexibility, ( I.E oil canning), but why hasn't anyone used aluminum for the ribs themselves? Seem like a place to shave a few pounds.

[n85ae]

Drink less beer, it's cheaper and saves more weight ...

[Ls1swap]

I thought it was a legitimate question. Allot of ultralights, and other kits use them. I know it's not much weight savings but every pound counts

[jrevens]

In my opinion, it would require a bit of “re-engineering”. The tubular spar structure interface is one area that comes to mind. The rigidity of a typical aluminum rib compared to the wood is another. By the time you got done, I doubt that weight savings would amount to much, if anything. The wood ribs serve the purpose very well. Bottom line - I believe a major re-design of the entire wing would probably be necessary, but that’s just a very off-the-cuff guess.

[n85ae]

Sorry, my reply was a bit sarcastic. The truth is, that a lot of builders spend a great deal of time trying
to save weight, and I suppose it makes sense, however a single gallon of fuel is often more than anything
that was saved in their entire build. A lot of guys would be better to lose 20 pounds themselves than
shave 5 off their build ...

In my airplane I find that weather/temp, fuel in the tanks, and passengers/baggage has a lot more influence
over how the plane flies than shaving 5-10 pounds ever would in the build process.

So my opinion I guess is just build the plane as well as you can is the most important thing. Weight saving
by using aluminum over wood ribs probably wouldn't amount to much, but half the fun is building - So why not?

Regards,
Jeff


I thought it was a legitimate question. Allot of ultralights, and other kits use them. I know it's not much weight savings but every pound counts

[Tom Waid]

The Aerotrek is similar to the Kitfox but the wings have aluminum ribs

22999

[jmodguy]

Rans also uses aluminum ribs and they have a pretty slick method of attaching the ribs to the round spars. Looks pretty light to me...
Every ounce you can save, whether the person or the plane will increase it’s performance! Do both... 😬

[bbs428]

Drink less beer, it's cheaper and saves more weight ...

Classic Jeff! Lol.

I try to build as light as I can but there's a lot of truth and wisdom in that statement.
At 235 lbs. I can and will shave 20-30 lbs. worth of performance robbing lard by the time I'm airborne! ;)

JMHO - There is a place for aluminum ribs - Kitfox is not in that category. Maybe there is an all aluminum wing in the future, maybe not. A lot of spam cans were wood and fabric before going all metal for longevity and durability. That being said - Wood and fabric have a solid place in aircraft design.