Curious as to people's opinion on the cost of weight savings on a cub? How much is it worth for you to save 20lbs? $1000? $2000? What's your magic number?
Curious as to people's opinion on the cost of weight savings on a cub? How much is it worth for you to save 20lbs? $1000? $2000? What's your magic number?
When I built my Cub, 10 years ago now, I used 100 a pound. If it was more than that it was usually a no go. But, you might also consider that some stuff is very difficult to change out later, so that may also figure into the equation. An example might be floor boards. Tough to replace later so you might bump the index up. But lets look at shock struts. Very easy to replace later so that might be a future weight savings project as finances allow.
Given all the inflation, (that we are told is not happening), you might need to up that 100 per pound to 150 or even 200 per pound.
IMHO and hope this helps
Bill
Very Blessed.
Wow, someone trying to interject logic into aircraft modifications.....
MTV
How much does weight really matter?? A few years back at Valdez the top 5 cubs where all within 10 ft combined distance yet the weight difference was around 300 lbs from lightest to heaviest. Weight does matter but it is an only a small part of the big picture. If you want to know if the 20 lbs matters. Go do a take off and landing with full tanks. Then repeat once you have burned off 3.5 gallons. If you see a difference then you have the skills to make it worth while, if not I would spend the money on fuel not parts. Sometimes adding weight to a plane will improve performance. Big wings, big flaps, 0360, Borer prop, Bushwheels, all add weight but improve performance. Having said that I am building a cub and will try use light stuff as long as it does not affect performance or function. Unless you have a very small motor cub, or need to work a 300 ft strip daily. Just spend the money on training with a good CFI spin/stall/aerobatic training will most likely improve your flying more than a 20 lb weight loss. I agree with Bill with inflation 150-200 per lb is now the norm. DENNY
DENNY
I believe the term is "Cubic Money"
Remember, These are the Good old Days!DENNY liked this post
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Lol, not sure logic and airplanes belong in thecsame conversation! Example, in 1980, it took approximately 15-20 steer calves to buy a decent super cub... Fast forward to 2022, those 20 steer calves won't buy a new motor for that same super cub. It would take two semi loads of steer calves to buy a nice super cub today...
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Saving 100# on EW doesn't mean you can carry an extra 100#.......unless everyone abides religiously to the 1750 GW. I built my cub with no real thoughts of weight saving. I carry tools, xtra fuel, survival, and comfort stuff all the time.
I watch my CG. Not being a STOL competitor or wanting to land in 300' my cub does what I need it to do. And yeah, I put on big tires...........but I went places with the old 8:00's years ago that would scare me with the bushwheels today.....but I look cool![]()
I'm sure you AK boys would roll your eyes but here's a shot of my payload and my Lab during the pheasant hunt at Randy's.
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That’s a hard pill to swallow. Mostly, I like being able to go to the store and buy beef, but I do have a ranching background. No wonder farms and ranches have so few airstrips anymore ☹️
Sent from my iPad using SuperCub.Org mobile app
I would be in pretty bad shape if I lost 50 lbs.
Weight savings on the airplane is all a compromise. The biggest changes to me is where that weight is removed. Up front sure does make a better flying airplane. You can spend a lot of money saving weight but do your skills feel the difference?
My train of thought is the further the weight is from your CG, i'm willing to spend more to save lbs. Pretty easy to take 30 lbs off of the nose nowadays with composite prop, lightweight (or no) starter, lightweight oil cooler, etc... I'm probably not going to break the bank trying to shave weight off of stuff closer to the CG of the plane.
It is a bell curve. The first five pounds is almost free, clean out under the floorboards, get rid of the stupid stuff like fancy cushions and gauges you don't use, maybe even the vacuum system. The next few pounds can be moderate: remove electrical stuff if you really want light, or change to light weight starter and alternator and battery, carbon floor and side panels.
Now you start into money with the light props, lift struts, going electric engine instruments, looking seriously at everything and getting the lighter options. This is small increments in weight for larger dollars.
The lighter it is, the more costly to remove another pound. OR, the less comfort you will have.
To me, weight saving on an airframe needs to be considered in combination with other factors. Such as
-Does this weight savings also increase performance in other ways? Example: A lightweight propeller MAY also considerably improve takeoff/climb/cruise performance.
-Does this weight savings impact comfort: Example: Using a partially inflated A/C inner tube as a seat cushion, in lieu of a confor foam seat bottom? Or removing all interior insulation increasing interior noise?
-Does this weight reduction offer better functionality? Example: Does replacement of multiple Engine instruments by an EI or JPI engine monitor offer better functionality and safety?
-Does this weight saving create additional safety, or does it make the airplane less safe? Example: Do Bigger or better performing tires offset the additional weight by offering better safety in the operating environment you fly in? (And, this is a BIG one....a lot of big tires out there are in fact "Cool looking" as opposed to truly functional).
Etc. I don't think you can or should really separate these kinds of considerations from the issue of weight reduction. I'll accept a little additional weight for better comfort, less noise, and better functionality. But, if a weight reduction also effects better performance, comfort or safety, I'm all for it.
MTV
To discuss weight savings in a Cub is a curious topic. If you want light? Fly a basic J-3 with small tires. But most of you don’t. Why? I’d guess those heavier mods mean enough to you to add them? Where do you stop?
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I intentionally added mass to my CubCrafters FX-3 after taking delivery. Each increase in aircraft mass brought me closer to the capability that I wanted when I placed my order. I chose to add to my "builder experience" by making these changes myself rather than paying CubCrafters for expensive options.
Delivered mass was 1149 lb for a day VFR aircraft with limited ability to operate on unpaved surfaces
Current mass is 1180 lb for a night IFR capable aircraft with improved ability to operate on unpaved surfaces
I'm still going into rough strips with the stock bungee/hydrasorb gear but Acme shocks will be here soon. (I don't yet know if they will make any difference to capability)
Weight/mass can reduce or increase. It's the change in aircraft capability that should decide if the change is worthwhile.
I'm more in line with Mike V's view on this. My own opinion is lighter is better as long as there is no impact to safety of flight. Especially during rebuilds, I try to stress that no additional weight is added without a specific reason. I.e., no installing wires, tubes, brackets, etc, because 'I might want (xxxx) at a later date'. And if you have a CG issue, placing a smaller weight at a longer arm makes more sense than heavy weight in the baggage or cabin. Great example is a nose heavy aircraft. Sometimes this can be dealt with by adding a fat tail wheel or a four leaf spring as the extra couple of pounds way out there has the same effect as a greater weight strapped into the baggage compartment floor.
As to the original post, I've always been told that it costs around $600/lb to remove weight from a certificated aircraft. Obviously this is above and beyond simply cleaning and removing interiors, but it's held up well over the years.
Web
Life's tough . . . wear a cup.
"As to the original post, I've always been told that it costs around $600/lb to remove weight from a certificated aircraft."
You can join WeightWatchers for less than that Web.
"Sometimes a Cigar is just a Cigar"
Back to the cost of a Cub to steers. My Dad bought a J3 Cub in 1954 for $500. He flew it for 3/4 years and sold it for what he paid for it. My buddy in Talkettna, filled his Cub that has Atlee Dodge LR tanks, on Monday with 100 Oct; he said it cost same as Dad paid for his airplane!�� That ain't right .
E
Most of my flying involves filling freezers. It's a way of life rather than a sport and the flying challenges are significant. Any mod that will ease these challenges and increase the odds of my freezers being full of fresh wild fish and game is a mod I'm interested in and willing to spend my kids inheritance on.
Jerry
Life's tough . . . wear a cup.DENNY liked this post
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For light weight stuff $600-$1000 a pound is about right after you get the easy stuff done, only option is to go to carbon fiber and titanium and it’s not cheap. Installed carbon fiber floor boards in the project in working on now and I think it’s about $800 difference over 1/4” Baltic birch and maybe saved 1lb ,1-1/2lb and the stuff is not fun to work with you’ll itch like crazy.
I don’t think I’ve ever spoken to anyone that didn’t wish their airplane was lighter. 200 pounds is about five seconds more off the water, maybe seven. 200 pounds makes a difference. But perhaps even more importantly it makes a difference on your “legal” useful load. I know some people don’t care about being legal with a useful load but I do.
I don’t think you’ll ever regret trying to build the lightest airplane possible within financial constraints.
Bill
With everything else being the same full tanks vs 3 gal of fuel about 50 ft takeoff and landing. DENNY
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I can tell you the difference between 900# cub and a 1100# is astronomical. Like with a capital A.
For light weight stuff, you gotta make real sacrifices - which also saves money - like leaving stuff off that you might like to have but really don't need. Like flaps (maybe), wing ribs (13 versus 1, alternators, starters, electrical systems, dual controls, gas tanks, instruments, extended baggage, cargo doors, float fittings, paint, metal belly, cargo pods, swing out engine mounts, square wing tips, etc....
Dont forget magnesium - like those new fangled oil sumps. You need all the -iums when you got the checkbook for it.
My 180 was 1558lbs when she rolled out the door in 1955 and has gained a solid 175lbs since. It's gonna cost a fair bit to get her back anywhere close. But mostly removing stuff.
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My point is that most cub pilots I know don't care if they take an extra 50' for takeoff or 5 secs. off the water. EW is not a big issue for the environment they fly in. In that case a light or heavy cub is a non issue.
My A model is legal at 1750# now..........it was legal at, I think, 2070# for Ag work. Feds must believe it's safer to haul more hazmat than camping gear.
"Sometimes a Cigar is just a Cigar"
Isn't it the case that the restricted Ag certification would have excluded passengers? If so, perhaps it was passenger safety that was the consideration. I know the restricted PA-18-180 glider tugs I flew had limitations on who could be in the back seat. I think the limitation was no one except for tow pilot checks.
Vinyl is the absolute worst,especially that 70's Buick station wagon naugahide everyone was so fond of back in the day. Pulled my Vinyl headliner and it was 6.7 pounds. New factory style wool liner was 1.2. Lots of crazy stuff on old planes and lots of w&b that have probably been inaccurate for half a century in some cases.
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