The International Cessna^® 170 Association

Seems this thread has strayed into wing mods, so here's one more for discussion: My '53 B model came to me with Demer's Super Tips from Madras Air Service, aka "Droop Tips." The seller swore by them, but the feeling among most folks I talk to is that if you have them, it's not worth removing them, and if you don't have them, it's not worth adding them. Consequently, I still have them, and don't have any basis for comarison of with and without.
Here are the claims, from Madras Air Service:
Increase cruise speed by 7-10%
Increase rate of climb by 20%
Stability improved by 50%
Reduces take off roll by 20-25%
Stall speed reduced by 20%

When I have flown side-by-side with a friend's stock 170B, it's hard to notice any difference. If there are any gains, I suspect they are probably in stability, not cruise or rate of climb.

Cheers,
Denalipilot

With so much improvement in your plane's performance, it must have been a real dog before the Madras tips, eh?

I don't recall if it was here or in the old Classic Club that I posted the experience we had when we converted the pipeline patrol fleet to Madras tips. (The amount of time spent in cruise, and the miles covered by the fleet operating from coast to coast in daily inspection flights, were bound to demonstrate a reduction in the time spent over known, repeatable mileages and years of fuel records.) But the bottom line was, they were a waste of good money and a restriction to visibility. After months of record keeping, no observable or accountable difference between the equipped and non-equipped airplanes was noted.

If my airplane were so equipped, I'd remove them, install original or replica-original tips, and sell the Madras to some hopeful, starry-eyed, someone who believes in the magic of snake oil. (For those of you who are angered by the bluntness of my response.... that was an opinion.)

denalipilot wrote:Metal Master- Would you venture an estimate of how much less runway you need with the 8043, all other conditions being equal? Maybe in terms of a rough percentage? My '52 B model came with the 76" prop, and I often wish I had more STOL capability on the shorter runways and frozen lakes around my area. I tend to carry an ample survival kit, wing and engine covers, preheater, snowshoes, tool kit... It seems to add up pretty quickly and so I have been looking into the 80" prop at my upcoming annual. Thanks to all the contributors on this thread, the comments have been most helpful. Lastly, is there some way I can tell what my current 76" prop is pitched at?

-Denali Pilot

It is signafcantly shorter but that is the one measurments we did not make. Our intention is to put cones along the taxi way and get actual performeance numbers against temperature & density altitude, Weight & CG.
I took the day off from working on airplanes yesterday to work on airplanes.

Okay, since this has evolved into a STOL/wing mod/seaplane prop discussion...........here goes.

My airplane is far from stock....a '55B with 360 Lyc, 80" csp, Sportsman's
STOL cuffs, [I think they add less than 4 lbs.], stock tips, seaplane mods etc. My son has a '53B here in Galena with the 360 Lyc, 76" prop, and Horton STOL with droop tips. Our airplanes are similar in performance but the Sportsman is BY FAR the best wing mod. It flys quicker and lands slower.......bottom line. It is lighter (thinner aluminum) and uses foam rib extensions. It is also a PITA to install. I did mine under the supervision of my friend and also IA; and it took close to 40 hours. I think a good sheet metal man who had done one before could do it in half that time. I have my airplane on floats during the summer so performance becomes an issue getting out of shorter lakes.

If I had a stock 170-B and wanted performance in take-off and landing I would put on a long flat prop and a Sportsman's STOL cuff.

Buck, Galena, Ak

buchanan wrote:...My airplane is far from stock....a '55B with 360 Lyc, 80" csp, Sportsman's STOL cuffs, .. My son has a '53B here in Galena with the 360 Lyc, 76" prop, and Horton STOL ...the Sportsman is BY FAR the best wing mod. It flys quicker and lands slower.......Buck, Galena, Ak

Buck, perhaps that's just the difference between the old bull and the young bull, eh?

I regularly receive catalogs from Harbor Freight, the Chinese tool store, and they have a magnetic device that is attached to your automotive fuel line. This device creates a magnetic field through which the fuel passes and straightens out the molecular clumps therein. This molecular allignment will result in a twenty percent (20%) reduction in fuel consumption.
For the life of me, I can't begin to immagine why Ford , Chrysler , and GM
waste all those millions of dollars trying to up the CAFE by a couple of miles per gallon when they could just buy this very simple device from Harbor Freight and all their troubles would be over. It only costs about $19.95 and I'm pretty sure it was invented and developed by the same guy that developed the drooped wing tips.
I'm personally surprised it hasn't been suppressed by the oil companys.

Yes, this is the kind of product I made a lot of money from proving to truckers on our dyno how it increases all the performance fields. I made the money and they lost . I call these type products, SNAKE OIL products. Most improvements are use of common sense and proven products.

John

blueldr wrote:... It only costs about $19.95 and I'm pretty sure it was invented and developed by the same guy that developed the drooped wing tips....

Hey, Dick! It's on sale this week for only $13.95 here in Dallas! How 'bout you and me buy the entire stock and we can make a MINT! WHHOOOOEEEE!!!! We're on the GRAAVVYYYY-TRAAAIIINNN NNOOOOWWWW!!!

(Actually we shouldn't be so hard of 'em. The little device is actually pretty handy. If no one has noticed, the exact same device ...two little magnets with matching/mate-ing semi-circular grooves designed to wrap around tubing....and held together with rubber bands.... is also marketed at some auto parts counters as "screwdriver magnetizers/de-magnetizers", but in that incarnation they usually sell for only $2.95. As fuel-line magnetic-aligners they don't use rubber bands, they use 10-cent plastic ty-wraps.
Perhaps the real money-maker is to buy the screwdriver thingy and then throw in 20-cents worth of ty-wraps and undercut Harbor Freight by a whole dollar, thereby clearing ......lemmee see now....ought and ought, and carry the eight.... Whoo-Hooo! we can clear a whole $9.80!!!

We can then sell the rubber bands on Ebay for 100% PURE PROFIT!

NOW you guys know why I am the Parts and Maintenance guy around here!!!!

Yeah, and if we do away with that expensive and needless motor oil and just run straight MMO we will get hundreds of miles per gallon! Hey... has anyone thought to do this in our airplanes?
David

I am not sure George but I think that was a rib

buchanan wrote: but the Sportsman is BY FAR the best wing mod. It flys quicker and lands slower.......bottom line. It is lighter (thinner aluminum) and uses foam rib extensions. It is also a PITA to install. I did mine under the supervision of my friend and also IA; and it took close to 40 hours.

If I had a stock 170-B and wanted performance in take-off and landing I would put on a long flat prop and a Sportsman's STOL cuff.

Buck, Galena, Ak

Buck I have heard from others that have tried both that the Sportmans is better too. In fact my A&P removed a Horton in order to install a Sportsmans on his C-180.

Bruce

N3243A wrote:...Buck I have heard from others that have tried both that the Sportmans is better too. In fact my A&P removed a Horton in order to install a Sportsmans on his C-180.

Bruce

Can you imagine the goofyness that sort of intensive-effort must strike with originality nuts like me?

Yes I suppose George. But performance is everything if you operate Part 135 off bush strips hauling hunters and deceased wildlife by the bagfuls like he does in the fall. Originality means squat to him. I have not installed the Sportsmans cuff yet, though I consider it from time to time. I think it adds like 18-19 lbs to the airframe if I recall correctly and yes it is uglier than a stock airfoil

Yeah, I was just being good-naturedly kidding.

I guess I don't understand the extent of such operations.... I would think that if someone wanted to be in that business another model airplane would be so much better suited. Something like a 185/206 comes to mind. Horsepower-to-weight is just so much more helpful to improved performance than airframe mods, in my opinion.
But I guess you've got to work with what equipment you've already got in many cases....
If it were me, I'd change airplanes I think.

My paperwork said 15 pounds for the Sportsman cuff.

Paul