Getting Ready for the September 20th "International Cox PT-19 Fly It If You Got It Day"!

batjac wrote:

And, you said earlier that you put tail wheels on your PT-19s, and it may help looping.  I don't suppose you could take a look at your best looper and note the c.g. position on it?  That'd give us mere mortals a good place to balance ours for more sprightly performance.  I understand that Cox made these to just fuel 'n go, but it would have been nice for them to give us some c.g. positions along with the beginner through advanced settings on the engine thrust.  

Hmmm... Maybe we could note things like this for reference data in a sticky in the "Cox Model Planes and Helicopters" section.  Perhaps I'll weigh my production Cox models and measure their stock c.g. locations tomorrow to start a thread.

The Off On A Tangent Mark

Hey Mark,

My "best looper"...or perhaps I should say, "The one that scares me the least" balances right at 1 1/2" from the center/front of the wing...or just past that molding hole in the center.


It also comes in at 9.8 oz. according to my el cheapo postage scale. This is without pilots (I sent them to a better, more appreciative home!).

It also has the Tornado "pusher" prop which, as someone upstream commented, might help it stay out where it's supposed to.



I should have a decent collection of these poor crates flying by "PT Day" on the 20th. The new one will lead a pampered life for a least a little while, but WILL be flown.

Think I may try to claim an Unofficial World's Record of Cox PT-19 Loops on that day, using the PT shown here. Any of you guys that might have Guinness of FAI connections let me know !!!!

World Champion Aspirer Kim

12 years old.. damn.. I wish I had more photos of my early years. Did you kids just get off the bus? (background)    or did you skip school that morning?   

I'm looking forward to the PT-19 fly-a-thon. Here's the model that got me into the hobby.. back around 1992. This is with a later replacement fuse.. (no pilots..)



I still have the old fuse... with pilots



It weighs in at 10.0 ounces.



There's currently a 6 x 3 R/H prop on mine.

The 1994 Cox replacement parts form lists the prop for the PT-19 as a 6 x 2 L/H (get a load of those prices!)



I bent-up a replacement gear for changing wheels. These are Sig 1/2A examples @ 1.375" diameter with spring-style retainers (probably accounting for the extra .2 ounces in weight..) It would be interesting to fly this model with no gear at all.. Anyone ever try it? It might make for that CG difference for pulling loops.  



anyone ever have this issue?

I have the tank.. but as you can see; it's been glued back on and didn't stay. Maybe there's room for a balloon tank in there... then maybe some sustained "inverted" flight could be achieved? (I can dream.. can't I?)


and my pin-stooge hole...

I had been using the inner-hole on the elevator horn, which is the current set-up... along with .015" music-wire solid lead-outs.

The problem with that is.. they get "buggered" if the wing pops off. I only had one handle and line-set made-up.. and I typically flew 3-4 models in an afternoon.. and this made it possible to switch. (I should have just used short lengths of Dacron with line-connectors..   )

Hey Roddie!

This was one of those cold Sundays when the ball diamond was a swamp, so we're launching our planes from the "grass" at the edge of the mud!  Nope, we didn't skip school...one of our Bus Drivers lived in the house just out of the frame.

Yeah, I wish I had more photos of those days!  

You could probably fit a small wedge tank up in the fuse to replace that plastic tank...I've got a metal Perfect tank in the Super PT, but am gonna swap it out for a plastic bottle when I come across one that looks right.

Not sure whether or not the PT would maintain inverted flight without a REALLY honking engine.  I MAY give it a shot at some point, but have already broken off the nose tab on half of my rudders, so it may not happen soon.  Thinking about it, the BIG deal would seem to be trying to get it back upright...but don't know...the mystery continues !!!

We did fly PT's with the gear left off, it made life a little easier landing on grass without it being jerked to a stop so quickly.  The biggest problem, the way I remember, was getting a good, clean launch with enough chuck-power to get it to speed without planting it!

I used to stare at the parts lists that came with these planes, planning my versions of "Up-Grades".  The results were sometimes painful, but ALWAYS educational!  I was REALLY ticked to find that adding an extra blade to a prop DID NOT make the plane fly faster !!!

Luckily, the hobby shop in Metropolis, Illinois--"Hop Johnson's Radio & TV Repair" kept a pretty full supply of parts, and I vaguely remember some kind of big cardboard display in the narrow side-room of the store that was the "hobby shop".  I always felt real "Official" plopping down lawn-mowing/paper route money for parts...in my mind, this raised me above just "buying toys"...I was now "Keeping My Operation Going"!

I've always used black carpet thread for leadouts on most of my 1/2A planes.  An aunt gave me a spool of the stuff that I'm STILL using after some 45 years.  I just tie loops in it, and use clips on the handle side to swap the lines between planes.

Yep, think the "International Cox PT-19 Fly It If You Got It Day" (trying to remember to always use Mark's Official Title) should be a hoot.  I intend to take the PT's on the road...loading them up and tracking down victims!  Figure a decent engine, with a three-bladed prop should produce a friendly flyer.

So far, I've got about five people on the list, warning them NOT to mysteriously disappear on September 20th!

Keep in mind if the plane is inverted. The best way to get it back upright is to whip the plane in the inverted position applying slight down elevator. Once the plane is high enough, tuck it under by applying up elevator. The plane will not lose any speed and will quickly right itself in the upright position. It will turn very rapidly. However this feels very abnormal. I suggest practicing this on a plane that your already confident flying. If you try and fly a sluggish overweight plane from the inverted position to the upright position by applying down elevator and flying the outside loop it will stall rapidly losing line tension and you know the rest of the story. Ken

Ken Cook wrote:             Keep in mind if the plane is inverted. The best way to get it back upright is to whip the plane in the inverted position applying slight down elevator. Once the plane is high enough, tuck it under by applying up elevator. The plane will not lose any speed and will quickly right itself in the upright position. It will turn very rapidly.  However this feels very abnormal. I suggest practicing this on a plane that your already confident flying. If you try and fly a sluggish overweight plane from the inverted position to the upright position by applying down elevator and flying the outside loop it will stall rapidly losing line tension and you know the rest of the story. Ken

Thanks for that advice Ken. That makes good sense. The only C/L stunt "tutorials" I've ever gotten, were either through this forum.. or through my own trial and error. I have flown inverted and back to upright without incident.. but I haven't done much more than that. This was with my small self-designed models that I built and flew 20+ years ago. I always wonder how those models would fly.. in the hands of an experienced pilot.

Why hasn't anybody put the september 20th PT19 day on the official CEF calender yet? I think it should be there don't you...?     

So, it occurs to me that it might be cool to put together a retro field box to use on our PT-19 Day, using the same little tool box that my Uncle Wayne packed "Back in the Day".

Got me an operating Perfect Fuel Pump, the hollow carcass of a later version of our cherished 1.5 Volt "Telephone Battery', some runnable original Cox Fuel (with some cleverly disguised 24% GlowplugBoy in a second Cox can as a back-up), and an old handle wrapped with new dacron string.

Gonna solder up some "C" cells to fit inside the telephone battery, and find a Cox Glowhead clip that doesn't have banana plugs...and off we go...BACK TO THE 60'S !!!!

Wonder if there's someplace where I can get Super 8 Movie Film for my ancient "Don't-Forget-The-Lens-Cap-Or-You'll-Be-Sorry" movie camera?

Now, cue "Green River", please !!!

Kim wrote:and off we go...BACK TO THE 60'S !!!!

Wonder if there's someplace where I can get Super 8 Movie Film for my ancient "Don't-Forget-The-Lens-Cap-Or-You'll-Be-Sorry" movie camera?

Don't forget your flairs and platforms. Anyway a good initiative, Kim!!! Couldn't you make an "official" drawing to mark the day?

Way cool Kim!

I don't have a PT-19, but if I did I would surely participate.

Well. you might need to be fixed up with a 'Loaner' !!!

OVERLORD wrote:

Kim wrote:and off we go...BACK TO THE 60'S !!!!

Wonder if there's someplace where I can get Super 8 Movie Film for my ancient "Don't-Forget-The-Lens-Cap-Or-You'll-Be-Sorry" movie camera?

Don't forget your flairs and platforms. Anyway a good initiative, Kim!!! Couldn't you make an "official" drawing to mark the day?

May have to look at that !!! Also, think there used to be an "STP" sticker on the side.... May have to make a run to the local shop to see if I can get one of those !!!

I would certainly fly one if I had one!
I watch some of the eBay auctions that go through, but most just seem way overpriced.

Try to swing this way on the 20th! I'm gonna be making a lap toward my uncle's house, then up 24/57, and over toward Scott AFB if Ron is still there. I'll steal some orange cones from the airport, and we can set up an "Official Circle" out back of some truck plaza !!!!

I never realized that those two 2-packs of 6 x 2 props that I scored last Spring from the hobby shop that was going out of business, were the stock L/H replacement prop Cat.# 864 for the PT19. I have to wonder how my speed reedie engine with Tee Dee .049 cylinder/piston and high-flow red horseshoe backplate would run with a 6 x 2 L/H prop? Has anybody ever run an APC 4.75 X 4 R/H prop with a hopped-up engine on their PT19? You may ask "why".. but as Kim mentioned.. a hot engine makes a BIG difference with this airplane.. if you want to try anything more than a wing-over.

A cool experiment, would be to modify the airfoil of that wing.. using a few balsa half-ribs and some "Saran-wrap" taped around the perimeter? The added weight would be marginal.. and would produce a more symmetrical airfoil. There's absolutely "nothing" in the way, on the bottom of that wing to try this.

Of course.. "just flying" your PT19 in level-flight, with some pics/video for documentation is what this event on Sept. 20th is all about. Maybe tow a "banner".. or incorporate a "balloon-bust" into your flight!! I like the retro field-gear idea that Kim mentioned!

Haza!

I finally picked up a 19 off ebay, and it is just what I wanted. It looks like it was flown for a season and put away wet: dried up rubber band melted to the nose and an engine so gummed up that after a week-long fuel soak I still needed a wrench to get the crank to turn. All clean now, and I have several days later this week to test her out.

RE Banner towing

Do we get double points if we pick it up on the fly like the full scalers do?

roddie wrote:
A cool experiment, would be to modify the airfoil of that wing.. using a few balsa half-ribs and some "Saran-wrap" taped around the perimeter? The added weight would be marginal.. and would produce a more symmetrical airfoil. There's absolutely "nothing" in the way, on the bottom of that wing to try this.

Or Monokote. I've been thinking about doing this for a long time. You've inspired me to put it on my to-do list. I have to fix a crack in my wing anyway. I'm trying to decide whether to fix mine up with a hot reedie or a Medallion. I only have one Medallion and haven't used it since my Li'l Jumpin' Bean days.
Even my son is looking forward to this upcoming event.
Rusty

P.S. Wow, I'm obviously feeling better this morning. Maybe now I can re-join the forum. I've missed you guys for the past week.
Rusty

flyjsh wrote:Haza!  

I finally picked up a 19 off ebay, and it is just what I wanted.  It looks like it was flown for a season and put away wet:  dried up rubber band melted to the nose and an engine so gummed up that after a week-long fuel soak I still needed a wrench to get the crank to turn.  All clean now, and I have several days later this week to test her out.

RE Banner towing

Do we get double points if we pick it up on the fly like the full scalers do?

AHHH! FEEL the happiness !!!!!!!

RE-Re Banner Towing...do I get triple points if I talk Patrick into holding the banner, with it's string looped in his mouth, while I try to snap it into the air using a three-prong fishing hook towed behind the PT?

Great to see the PT-19 population picking up !

RknRusty wrote:

roddie wrote:
A cool experiment, would be to modify the airfoil of that wing.. using a few balsa half-ribs and some "Saran-wrap" taped around the perimeter? The added weight would be marginal.. and would produce a more symmetrical airfoil. There's absolutely "nothing" in the way, on the bottom of that wing to try this.

Or Monokote. I've been thinking about doing this for a long time. You've inspired me to put it on my to-do list. I have to fix a crack in my wing anyway. I'm trying to decide whether to fix mine up with a hot reedie or a Medallion. I only have one Medallion and haven't used it since my Li'l Jumpin' Bean days.
Even my son is looking forward to this upcoming event.
Rusty

P.S. Wow, I'm obviously feeling better this morning. Maybe now I can re-join the forum. I've missed you guys for the past week.
Rusty

I'm glad you stepped up! I was feeling like a slouch for cowering away from this experiment...my inventory of un-busted rudders is running rather low !!!!

Also, GREAT to hear you're feeling good AND recruiting new victims! We're gonna need all hands on deck for the up-coming silliness !!!!!!

So, if one were to video this event on a budget, what aircraft mounted cams are people using? And what cheap stationary mounted cams?

Kim wrote:

flyjsh wrote:Haza!  

I finally picked up a 19 off ebay, and it is just what I wanted.  It looks like it was flown for a season and put away wet:  dried up rubber band melted to the nose and an engine so gummed up that after a week-long fuel soak I still needed a wrench to get the crank to turn.  All clean now, and I have several days later this week to test her out.

RE Banner towing

Do we get double points if we pick it up on the fly like the full scalers do?

AHHH!   FEEL the happiness !!!!!!!

RE-Re Banner Towing...do I get triple points if I talk Patrick into holding the banner, with it's string looped in his mouth, while I try to snap it into the air using a three-prong fishing hook towed behind the PT?

Great to see the PT-19 population picking up !

Hey now Kim, I don't think you took my question seriously

Model Airplane News in the 70s did an article on banner towing, but they had it attached pre launch. If Im going to tow a banner (about the only thing I avoided as a low time commercial pilot), by god I am gonna do it right and risk props and plastic to pick it up in flight!

Well just as well...doubt even Patrick would go for my plan!

Seriously though, the banner idea sounds cool...I may have to give it a try too, but will probably go with it attached at launch.

Back in the 80's, I did some banner/flag towing with my Sig Kadet, and while the hook and go method looked cool when it worked, it could be a hassle if things weren't just right. Admittedly, my system probably could have used some refining too.

I eventually started using a longer tow-line, stretched out ahead of the plane, that allowed it to get up, into a good climb, snapping the banner up behind it. I had the line attached to a Robart bomb release so that I could turn the whole thing loose for landing.

If my poor PT does the tow-thing, it's just gonna have to drag it up and be dragged down!

flyjsh wrote:So, if one were to video this event on a budget, what aircraft mounted cams are people using?  And what cheap stationary mounted cams?

I've been torturing the little key fob cameras I got on Ebay. And figure about any ole video camera on a tripod ought to do the job from the ground.

Kim: do you have the part number of the key fob camera you purchased from ebay? I have looked at several, but none seemed to to have the right focus distance or right pixels per inch or whatever.
  thanks for any help you can give.
    p.s. what video editing program do you use.     happydad