P-STOL Flaps on a Javron Cub

[Steve Pierce]

So I had a friend who is building a Javron Cub reach out the other day and ask a question about P-STOL flaps on the Javron. He was told by another builder that the P-STOL flaps cause the Javron wing to flex and create a higher stall speed. He said Javron uses .020" 3003 aluminum for their leading edges which kinda surprised me. Piper got away from 3003 on the 150 hp Super Cubs and went with 2024-T3 if memory serves me correctly. I know Univair skins are 2024-T3 .020" and Dakota Cub uses .025" 5052. I have dealt with 3003 on J3s and Short Wing Pipers and know that it is very soft and dents a lot easier. Has anyone had any issues with P-STOL flaps on the Javron?

 

[ak49flyer]

First I’ve heard of this- there’s a few of those around here and I’m not aware of any issues or complaints. Interesting that the LE is the topic of discussion- I’d assume those flaps put a lot more force on the tank bay skin, false spar, rear spar, etc.

 

[Idaho180]

Thanks for posting the question Steve. Just got my Javron kit and getting ready to order the Pstol flaps. Sounds like a question for Jay. I’ll try to call him Monday.

 

[supercub83a]

Javron uses .020 leading edge. The original piper I believe calls for .016 sheet metal. I have 3 hangar pstol flaps, 2ft exteneded each side on my Javron and have no problems with any kind of flexing. I believe the statement to be inaccurate. I also have leading edge slats and have tested them to over 130 IAS with no problems or flexing noted.

 

[Mr. Ed]

I’ll be interested in hearing what Jay has to say. I don’t know what the leading edge skin is but I have a hard time believing that the flaps cause the wing to twist. To get it to twist the front strut would have to flex. The jury struts keep those things pretty rigid. With the flatter (nose lower) attitude the pstol flaps create, these folks may be seeing a knot or two higher indicated airspeed which may simply be due to the pitot probe not being pointed at the sky. Just spitballing here but I don’t buy the wing flex.

 

[DENNY]

So I had a friend who is building a Javron Cub reach out the other day and ask a question about P-STOL flaps on the Javron. He was told by another builder that the P-STOL flaps cause the Javron wing to flex and create a higher stall speed. He said Javron uses .020" 3003 aluminum for their leading edges which kinda surprised me. Piper got away from 3003 on the 150 hp Super Cubs and went with 2024-T3 if memory serves me correctly. I know Univair skins are 2024-T3 .020" and Dakota Cub uses .025" 5052. I have dealt with 3003 on J3s and Short Wing Pipers and know that it is very soft and dents a lot easier. Has anyone had any issues with P-STOL flaps on the Javron?

Never seen it. Never heard of it. On a stock or Javron wing. Sooo what part of the wing flexed? Was it inboard? Outboard? Entire wing? What washout was the wing set at? What other mods did the wing have? Was the fuselage correct? Did the pilot have the skill to properly fly the wing? What was the stall speed difference??? A Javron wing is stronger than a stock wing just for starters. If Steve Pierce said it was a before and after issue I would believe it but some dude knows a guy. NOPE!!!

 

[BC12D-4-85]

There is aileron reversal that with a deflected control changes the wing's chord line...and could at high speed twist the wing at the rear. That affects AOA and stall. If larger or longer more loaded flaps can do that.....?

But it's common knowledge that the flapped portion of the wing when deflected can stall "for that section" before the remainder that's unflapped. Stalls inboard first. Increase in flapped chordline angle does that. How does that affect the overall stall speed of the airframe when the flaps are deflected? Typically it lowers that speed about 10%.

Gary

 

[fishhook]

Lots of javron wings used in mackey style builds with way bigger flaps than any pstol setup ever imagined with no issues. Front and rear spars reinforced at lift strut attach, leading edge javron stock. The stuff jay uses is not 3003 its something else like said before. Definately not 2024 I dont think though. Behaves different than 5052.

 

[Scott A]

Just got off the phone with Jay. With over 300 sets of wings out there and guys hanging all kinds of crazy flaps and leading edge devices on them, there was never a problem with twisting - but he did know exactly who was making the claim and it sounds like improper rigging. He also confirmed that the leading edge is .020 and is 3003-H14 (as mentioned above the original Piper was .016 3003).

 

[Steve Pierce]

Just got off the phone with Jay. With over 300 sets of wings out there and guys hanging all kinds of crazy flaps and leading edge devices on them, there was never a problem with twisting - but he did know exactly who was making the claim and it sounds like improper rigging. He also confirmed that the leading edge is .020 and is 3003-H14 (as mentioned above the original Piper was .016 3003).

Thanks, my Javron builder friend tried calling Jay but could never get him to answer.

 

[supercub83a]

I woudlve sworn that Jay told me it was 2012 sheet metal or something in 2000 series. Maybe that was the boot cowl…

 

[Scott A]

I woudlve sworn that Jay told me it was 2012 sheet metal or something in 2000 series. Maybe that was the boot cowl…

Yeah, and it doesn't 'seem' as soft as the interior panels I have that are 3003 - although I've managed to put a few dents in my leading edges without much effort. I think I will need to use Poly Fibers SuperFil before covering.

 

[supercub83a]

Would make me feel a little better about having those slats pk screwed into the leading edge if it was 2024. Havent heard of any coming loose though.

 

[fishhook]

I stand corrected, it is 3003 as said before, interestingly like said before it behaves different from the 3003 I buy and use for non aviation purposes. I too have not seen anyone have issues screwing pks into javron leading edges. A few friends I know apply stewarts glue or other various glues to the screws to prevent loosening. Only issues I have seen were guys pop riveting them. On my next set of wings I would definately pay more for 2024 leading edges if Jay would offer it. As said before they do dent if you drop a tool on them (experience talking.)

 

[Scott A]

^^ agree - I would pay more for the 2024 also due to self induced dents.

 

[Steve Pierce]

I have rebuilt a lot of Piper wings over the years. I am not a fan of 3003 aluminum. Besides the issues with the soft aluminum denting it is also more prone to cracking and screws on leading edges and false spars working, wallowing out the material and getting loose. This seems to be what some have found on the Javron wings with P-STOL flaps from the conversations and pictures I have seen as a result of this thread.