Potential 95 Super Cub Empty Weight?

[Eric84]

There's lots of little Cub guys on here who will say they're unnecessary.....

Yes.. I've been reading that, that debate has been raging here for 20 years although the preponderance of voices agree don't screw with a light 95.

The keep it light guy in my head even says to cut out all the tabs and such that were put in at the factory on the frame for the flaps If i don't have flaps I don't need the weight of the tabs.

 

[MainlandCub]

The keep it light guy in my head even says to cut out all the tabs and such that were put in at the factory on the frame for the flaps If i don't have flaps I don't need the weight of the tabs.

I nearly wrote that, but thought it might be viewed as subversive..... :lol:

 

[BC12D-4-85]

I recall adding about 20# when installing flaps on a PA-11. They work on landing, but don't add much on takeoff until you're almost airborne. There's simply not enough thrust from a C-90 to blast air over them on takeoff for more lift. Anything more than 12* and they'd slow the takeoff on floats until water speed was gained.

Gary

 

[Eric84]

I recall adding about 20# when installing flaps on a PA-11. They work on landing, but don't add much on takeoff until you're almost airborne. There's simply not enough thrust from a C-90 to blast air over them on takeoff for more lift. Anything more than 12* and they'd slow the takeoff on floats until water speed was gained.

Gary

Gary, thanks so much for the input . could you explain the anything more than 12* than ?

Edit: I now assume you meant 12 degrees..

 

[Eric84]

Go ahead and be subversive!

 

[BC12D-4-85]

Gary, thanks so much for the input . could you explain the anything more than 12* than ?

Edit: I now assume you meant 12 degrees..

Yes flaps half way to their first setting which is at about 25 deg. If I lowered them progressively to 25 while accelerating (mainly on floats which takes longer) their initial drag could be felt. So I used half of that until 35-40 then 25 deg for takeoff. Today I'd leave the wing as Piper intended and only add VG's unless I had more power than 90, then add flaps.

Gary

 

[skywagon8a]

... gas tank cover- make everything so a cover can be installed but cover with fabric to start with??? just a thought.

An unsupported section of fabric the size of a gas tank on top of the wing could be excessive. There should be one or two fixed ribs on top of the tank to hold the fabric down. Particularly in the propwash area. I watched the fabric peel off the top of a wing once. The airplane became uncontrollable and fortunately for the pilot he was wearing a parachute, which he used.

..... but don't add much on takeoff until you're almost airborne. There's simply not enough thrust from a C-90 to blast air over them on takeoff for more lift. Anything more than 12* and they'd slow the takeoff on floats until water speed was gained.

Gary

Flaps on a low horsepower seaplane add aerodynamic drag unless there is considerable wind blowing. The initial getting on the step phase is strictly powering through the water, forcing the "boat" hulls through the water and up on the step. Lift on the wings is negligible initially (unless the wind is blowing). 10 or 12 degrees does sound like a maximum useful setting for lift over drag.

 

[BC12D-4-85]

On another note, the PA-11 had extended wings with droop tips (CC style) when I bought it. More wing area. I liked the lift on floats and assumed that installing flaps on the wings we had converted back to rounded factory style tips would result in the same. On floats I felt I had lost takeoff performance after that restoration to factory wing area.

Gary