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Drastic measures needed to loose weight!

cgoldy

Registered User
Moogerah Queensland Australia
Hi from Down Under,

I have been awol for a while. Busy flying. But I have a bee in my bonnet about stripping some weight out of my Backcountry/Javron cub.

I will have to teach myself about carbon fibre I think.

But firstly I want to strip the 10 gallon long range tanks out of my wings, replace my borer with a lightweight composite and maybe a lightweight sump.

Then build some CF doors, floorboards, nose bowl and whatever else takes my fancy. Might be dreaming that I will get it all done but I will start on the easy bits first.

So some questions please.

Any suggestions as to how I should attack the Back county's 10 gallon tanks installed the the wings? (circa 2008 ) These were dropped in from the top if I remember correctly, and the brackets slipped under the extended leading edge and sit on the spar. I think I had to pop of some rivets to do that. It takes up one bay and has no tube running through it. I'm worried that I will damage a lot of fabric in the process. Would it be silly to think I could make a hole in the bottom and just start hacking into them with some sort of cutting tool?

What type of prop is recommended these days? Looking for a climb prop not cruise. All of airport operations. O375 engine solid crank.

Any suggestions re light weight sump?

Thanks in advance,

Colin
 
EarthX makes a light battery. Quite a bit of weight reduction per $100

Sent from my SAMSUNG-SM-G870A using Tapatalk
 
I vacuum bagged my own floor panels (carbon fiber & honeycomb sandwich) in my SQ-2. Saved 10 lbs (!!) over the standard kit wood floor panels.
 
If money and work is not a real concern: Catto prop, magnesium flywheel and sump, carbon fiber floors, EarthX battery.

With all this weight lost and my type of flying, I would keep the extra gas tank just in case...
 
Starters are heavy. You have to take your arms with you anyway, might as well use them.
 
If money and work is not a real concern: Catto prop, magnesium flywheel and sump, carbon fiber floors, EarthX battery.

With all this weight lost and my type of flying, I would keep the extra gas tank just in case...

good point Olibuilt!
 
Realistically, how much weight are you expecting to save with all these expensive mods? Enough to make a difference? Are you wanting to reduce the empty weight so you can carry more load up to your legal gross weight? Or wanting to be lighter to increase performance? Are your operations that critical that the weight reduction from the mods you're considering would make a difference? How much performance increase would you get if you just carried 5 gallons less gas?

Since 2013, I've removed more than 60 pounds from my plane's flying weight,...directly from the pilot seat. Didn't buy a part or STC, just lifestyle change (I retired) and better eating habits.

Jim
 
Ok, Thank you for your interest in my carbon fiber floorboards. A few hours of assembling text and links to all the pertinent resources I have an 8 page PDF. I'm happy to create a new thread, but the first post would be pretty darn long! If SJ or folks want a new thread I'll create it. In the meantime, here is a link to the PDF (first draft--feedback, input, questions all appreciated). My email is at the end of the PDF, or PM me here.

https://eaerofab.com/docs/SuperCubFloorBoardsV2.pdf
 
Since 2013, I've removed more than 60 pounds from my plane's flying weight,...directly from the pilot seat. Didn't buy a part or STC, just lifestyle change (I retired) and better eating habits.

Jim

Best Cub mod going. If only I had the discipline for it. Well done Jim.



Transmitted from my FlightPhone
 
Bloody hell Jim, If I lost 60 lbs I could fly without the need for a cub. Happy days! But well done.

Yes a lot of my flying is critical. I like to push the boundaries a bit. But it is the inertia that needs to be arrested when landing that I would like to reduce. I would love it if one of you educated ones could calculate how a reduction of 100 lbs of weight would effect the landing distance if all other parameters stayed the same. Sounds like a job for Skywagon I reckon.��
 
That's above my pay grade Colin. :lol: Here is an approach for you to try. Start by adding 100 lbs to your normal weight and collect some data. Then take the 100 lbs out and collect that data. This will give you an approximation of what 100 lbs will do. Also note what your center of gravity is. That alone will make a difference when shifted fore and aft. You may find that adding ballast to the tail will assist in reducing ground runs. For the weight change data to be correct you must be sure that the CG is unchanged for a strict weight comparison.
 
If (and only if) your wheels do not slide on the ground in a maximum performance stop, then the stopping distance would be linear with weight, assuming touchdown speed remained the same. However if your tires are sliding, the result would tend toward independent of weight, depending on CG. I like Skywagon's approach - it's mighty tough for pencil and paper to beat good data!
 
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What type of landing gear do you have? ASOS or some of the newer shocks go a long way toward keeping the tire in contact with the ground and allowing you to brake. For landing slower a set of the airframes new extended flaps is most likely best bang for the buck. For saving weight in floor boards, cut out center section and under the front seat. You only need floor where your and passenger feet go. Cover hole with single layer E glass, CF, or thin aluminum.
DENNY
 
CGoldy. I have lost 20 pounds in about 4 months doing South Beach diet. same results after reading "Sugar Blues" and also "Wheat Belly".

After this last lodge season (eating good food with lodge guests) I am due for another reading of Wheat Belly.

Seriously, over the years I have stopped eating sugar for a year and also stopped eating wheat for a year and had the exact same results. My body sees them the same. No other lifestlye changes, same results.

Kent Tarver of Aeromatic Propeller fame put me on track for taking sugar off my menu. It worked great.

I need to lose 25 pounds this time around.

You can lose alot from you airplane by getting rid of your fuel tank covers and going with fabric or Carbon fiber covers.

Is your plane a Smith/TurbineCubs/BackcountryCubs? Their wings are quite a bit heavier than Pipers
 
Kent Tarver of Aeromatic Propeller fame put me on track for taking sugar off my menu. It worked great.


Kent's position on sugar is militant. From his perspective sugar is the root of all medical problems. Medicats as he calls doctors are evil.....Kent and I had more than a few not so friendly debates...
Because of his.....ah..... position, I eat considerably less sugar ....anyhow... weight loss is about caloric intake. A 300 pound person needs to consume xxxxx calories per day to maintain 300 pounds.. Want to loose weight....you can eat the same foods but you must eat smaller portions....and instead of drinking a full can of sugar....drink a half a can of sugar...err I mean pop.


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You can lose alot from you airplane by getting rid of your fuel tank covers and going with fabric or Carbon fiber covers.

Is your plane a Smith/TurbineCubs/BackcountryCubs? Their wings are quite a bit heavier than Pipers


Good points Dave. Yes the wings are heavy. They have those extended leading edges which does not help. Not a lot I can do about the unless I strip the fabric off which I am not prepared to do just yes. But beautifully built by I think Wayne Axelson. Does any one know who did build them.? I think they came from Canada?

Not sure I want to loose much weight. I'm happy with 180 lbs
 
Bloody hell Jim, If I lost 60 lbs I could fly without the need for a cub. Happy days! But well done.

Yes a lot of my flying is critical. I like to push the boundaries a bit. But it is the inertia that needs to be arrested when landing that I would like to reduce. I would love it if one of you educated ones could calculate how a reduction of 100 lbs of weight would effect the landing distance if all other parameters stayed the same. Sounds like a job for Skywagon I reckon.��
Hi Colin,if the strip is that tight go somewhere else.It could be cheaper!
 
You might want to review Bill Rusk's thread on his build. cut out fly wheel, light sump, and lots of light.

Simple changes, starter, generator and such cost 10-100/lb. Floor boards about the same. From there you go to $500/lb, then $1,000/lb.

Your choice, but as above, find another place to land and walk.

Pull tanks out the top, easier to hid the patch.
 
Before you do much, I would take skywagon's advice and see just how difference 50 or 100 lbs makes in your stoping distance. It might not be worth the effort. At Valdez last year the top 5 in the prelims with 15 on the nose had only 9 ft difference in combined total distance between them. But 300 lb weight difference from light to heavy. If you normally fly when the wind is blowing 50-100 lbs is not that big of a issue if you fly a lot in no wind conditions it will matter more. Load up and see just how much.
DENNNY
 
Another consideration would be to install Doug Keller's slotted flaps for increased lift. Increased lift does what reduced weight does for performance. But then if you can also reduce the weight :).
 
Colin

The wings were probably built by Wayne Axelson. They are stout, but unfortunately they are/were heavy. A new set of wings could drop your weight by well over 75 pounds. But that is a pretty drastic move.

Catto prop = 25 pounds
EarthX battery = 10 (depending on location i.e. long cables if in rear of acft could be 15 pounds) mount it on firewall
Sump 7 pounds
24 gallon tanks add weight as most folks tend to fly with full tanks so you carry an extra 12 gallons of gas plus the extra weight of the tanks = 80 plus pounds
(i.e. use 36 gallon tanks and if you need to go long use a fuel pod. Weight is down low and removable)
Floorboards could save 10 pounds
if on 35" tires go to 31's = close to 50 pounds
Case mount alternator B&C 20 amp plus a light weight flywheel could save 5 to 7 pounds
Some folks have HEAVY seats. You could drop 15 to 20 pounds here depending.
Interior panels - leather covered .025 Vs .016 with fabric (no foam backing) or just painted. 10 plus pounds



Unfortunately the entire airframe is heavy to start with, so it will be difficult to make it feel, and fly, light. You can improve it some but a lot of that weight is built in and can't be changed. If I remember correctly the tail feathers for that airplane are 7 pounds heavier than a stock Cub. The tail feathers don't normally fail (or fall off either) so why are they beefed up? The website for the current Backcountry Cub shows an expected empty weight of 1440. That is heavy and it will fly that way, but that Cub has a certain niche, and mission, and that may be the price you pay for being able to fly a quartered out Moose (and a Carribou) all in one flight. It is all about the mission.

However, I have noticed on several cubs I've flown, that the aileron cables are rigged too tight and that will make them "feel" heavy and make the whole airplane feel doggish and heavy. You can rig the rudders and elevator as tight as you want and it will not affect the "feel" of the airplane but the ailerons are different. Sometimes just one turn looser on the aileron turnbuckle will make a HUGE difference in how the airplane feels and flies. I like a little bow in my aileron cables in cruise flight when I look out the wing strut. This is easy to do and cost nothing. Try it. Play around a little and see what you like.


Hope this helps some

Bill
 
....anyhow... weight loss is about caloric intake. A 300 pound person needs to consume xxxxx calories per day to maintain 300 pounds.. Want to loose weight....you can eat the same foods but you must eat smaller portions......

Please post this on the thread about insulin resistance, I want to see the fur fly.....
 
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