Skylark airfoil variations throughout the years.

[Brent Williams]

The topic of variations to the Skylark design has been visited many times on the fora.  Since it's winter and I look forward to the discussion, I thought this view of the Skylark airfoil variations might be interesting.   I resized all of these airfoils to the same chord length and pasted them to the attached pic.  Interesting to see the variations.  I have read that Ed approved of both the Bill Byles and RSM plans.  

For another fun comparison of the classic Skylark to a modern and very competitive design, I included Igor Burger's Maxbee airfoil in the group.  When comparing the airfoil shape of the RSM Skylark to the Maxbee, both are very similar in shape from the LE to the high point.  To my eyes, the high point on the Skylark is slightly more forward than that of the Maxbee with Igor's being slightly thicker through the curve from the high point the the TE.  

Paul Walker has dropped hints that he has, or might build a Skylark with the non-linear mechanism and E-power.  If so, it will be fun to read about this modernized classic.

[Dan McEntee]

  You left out the M.A.N. plan. it's close to the Soutwick/Byles/RSM plan in span and airfoil thickness. I haven't had time to dig out a sterling plan yet to compare but it's smaller that the magazine plan.. And you are right, it's an interesting subject. I feel very fortunate to have met and talked with Ed at a couple of VSC  contests before his tragic passing. I got one each of Ken Smith's kits before he also passed. Been trying to decide on a "gotta build" subject and all this discussion on the Skylark may help me decide!
  Type at you later,
   Dan McEntee

[Brent Williams]

The M.A.N. airfoil is the one at the top labeled M.A.N./Sterling.

Some of the variations in the aft section of the airfoil can be attributed to the TE and flap thickness.

[eric rule]

Very interesting comparison of the airfoils.

I know from many conversations with Ed Southwick how upset he was with Sterling and how pleased he was with the plans drawn by Bill Byles. He also fully approved of the AutoCAD plan drawn by Pat Johnston so I suspect that the biggest difference between the Byles and Johston airfoils was simply a matter of hand drawn vs machine drawn.

I sure miss Ed and Helen! Two of the nicest people I have ever had the privilege and honor of knowing.

[Dan McEntee]

   Hi Eric;
   On one of my first trips to VSC I got to meet Ed Southwick and was having a nice conversation with him. Then I asked a question about the Sterling kit (not knowing the history of things at that time) and boy THAT was the wrong question to ask him! I started to look for a hole to crawl in but changed the subject quickly and he went back to his gracious self again. I asked Chris McMillin about why he got that upset and he filled me in. I never mentioned the "S" word in his presence again! Ed wasn't very tall but sure is a giant in the history of stunt
   Type at you later,
    Dan McEntee

[Chris McMillin]

Dan,
Remember the guy that built the purple free flight model that hung in the shop for years? Kerry Madden? He had a Sterling Skylark that was powered by a Fox 40, we taped up some holes and the hinges and took it out to The Spirits R/C field and put in about 5 flights with it. Great flying model with a ton of power. Had a lot of potential but he never went on with it. I think those kits are as good as they are straight, kind of like a Jetco Shark or an RSM version. They all fly pretty good.
Chris...

[proparc]

This is something I am VERY interested in. It always seems to me that the Skylark aerodynamics was way ahead of its time for then.

[Scott Richlen]

Back in the late 60's when the Sterling kit came out one of my flying buddies, Cpl. Roseberry stationed at Ft. Missoula built one.  He did a hobby-poxy finish on it.  I didn't know enough to ask what it weighed, but it was beautiful!

On the first flight he did a wing-over and the thing went straight into the parade ground lawn up to the leading edge of the wing!  Sticking up like some kind of javelin!  He pulled it out and it had sheared off the prop blades with no other damage to the plane.  Maybe some to his ego, though.

It was too heavy to do much than round and round.  I don't recall if he ever flew it again.  He started fiddling with RC and then he got sent to Vietnam.  Life is like that I guess.

But I always thought it was a beautiful airplane.

Scott   

[bob whitney]

  OK so if you were to build a Sterling Sky Lark what would u change

[Dave_Trible]

You can build it exactly like the kit but use light wood and have a very nice airplane.  As mentioned elsewhere I'm building one from the kit but stretching the wing to its original 56".  I think this was the major complaint Ed Southwick had with Sterling who shortened the span for economic reasons.  The only other changes I'm making are to use longer control horns which are more like current standards,  hoping to make the feel at the handle less foreign to my other machines.  It's really hard to change airplanes for different contests when they handle so different.  Even with these changes it will be a challenge.  Hence I likely won't even test fly my new one till after the Nats.

Dave

[Balsa Butcher]

fwiw the RSM kit plans show three versions, any one of which can be built from the kit: 35 size, .46 size (longer wingspan, classic legal) and the 60 sized that Ed flew in the 90's (not classic legal).  On my soon-to-build list fer shur!  

[john e. holliday]

If you guys had been at VSC when Ed and his wife were their with his Sky Lark you would have seen the differences in the planes.  The one he flew was a lot larger than the kit plane.  I think John Ashford even had his kit plane there that year.   Don't hold me to it as it has been years ago.   

[Balsa Butcher]

You are right Doc. Saw Ed compete with it a few times at Whittier Narrows. Ed flew the (big) .46 Skylark in Classic, the (bigger) .60 size in Expert. The .60 size may be the one pictured in this post. Either can be built from the RSM kit. Bill Byles (as well as Eric) would have more details.  

[Randy Cuberly]

I have plans for the Skylark given to me by Ed sometime in the late 1980s (I think) when he first moved to Arizona and often flew with us in Phoenix.   They are nearly Identical to the plans drawn for the RSM Kit except that they only show the 35 size airplane.  The airfoil and construction is exactly like the RSM kit.  The RSM kit plans look very much the same except that they show extended wing panels and stab/elevator lengths.   
Laying my plans over the RSM Plans shows nearly identical configurations.  Ed told me at the time that these were the plans He had used for all his Skylarks and that the old kitted version was not at all like his airplanes.  He said it with a distasteful smirk!!

Randy Cuberly