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C/L length

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C/L length

Post  OhBee on Sun Mar 27, 2016 12:54 am

Hey guys....trying to get my ducks in a row before my first flight in over 50 yrs.! Is 40ft. too long for control lines on an old PT-19? I marked it out on the ground ,and it sure didn't look very long! I know in the day we used to fly the bigger stuff on 60 ft. lines. The old Dacron lines that came with the PT measured 36 1/2 ft. I didn't care to trust 50 yr. old Dacron, so I'm now using 15# braided fishing line. THAT I have plenty of as fishing is my other "thing"! Thanks!....Steve
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Re: C/L length

Post  NEW222 on Sun Mar 27, 2016 1:32 am

As I do not have an original Cox PT-19, I cannot answer that. But, if you had 36 1/2 foot lines on it from before and it flew, I would just use that length. I was honestly going to say 25 foot, as I have heard that the 'plastic' planes were heavy and needed shorter lines to get them to go. I am sure however, that someone else here with an original will chime in and give you the real answer you are looking for.
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Re: C/L length

Post  OhBee on Sun Mar 27, 2016 1:57 am

Yeah...I was concerned about screwing myself into the ground! I'm dizzy enough as it is! These things aren't very heavy compared to the P-40 I had as a kid! Wish I hadn't left that somewhere in one of my many moves the last 40 yrs.!
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Re: C/L length

Post  Oldenginerod on Sun Mar 27, 2016 3:57 am

Steve.
I did reply prior to NEW222's answer, but it managed to vanish. What I said was that 40 foot is probably too long for this type of plane. The line drag is great and the plane could turn in, although the PT-19 used a left hand prop which would help to roll it outwards rather than in. Then, the trouble with shorter lines is that you spin too fast, so for someone getting back into spinning around after a long break, I'd recommend 30-35 foot lines and de-tune the engine a little to slow it down. Just tune it fairly rich for the first couple of flights. If the "dizzies" goes ok for you, then step it up a little. Once you have it sorted out & you know what the plane can do, then you may be able to lengthen the lines a little more, although the longer you go the less responsive the controls will be. Personally, I think 35' is about right for any 1/2A plane apart from something really quick. If a plane is really quick, then it can probably cope with the longer lines.

Rod.
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Re: C/L length

Post  Admin on Sun Mar 27, 2016 5:02 am

Oldenginerod wrote:
I did reply prior to NEW222's answer, but it managed to vanish.  

Were you sure your post actually went through (as in you saw it posted) before closing your window or loading another page? A few people claim to lose posts but I've never actually experienced it. Not disappearing after it was posted at least.

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Re: C/L length

Post  rsv1cox on Sun Mar 27, 2016 6:15 am

I screwed myself into the ground flying a PT-19 on 25' lines and fell flat on my face after only a few laps and a hiatus of 35 years between flights.

I would recommend 35' lines and some turning in place before attempting any air time. I wouldn't think that old Dacron in good condition would be a problem, but I would look carefully at the attachment points.

Bob
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Re: C/L length

Post  Kim on Sun Mar 27, 2016 6:43 am

Yeah, 35 feet is just fine for the Cox PT-19.  It WILL seem to turn plenty fast even on that length...do make sure you pick a calm day--early in the evening is often the best time.  A three-bladed prop from Matt or Bernie will also slow it down while still letting you peak the engine at it's best needle setting.

You can also do some ground-bound test runs, measuring the amount of fuel you load to limit the flight to a few laps.

Of all the solid plastic RTF's the PT seems to have to best glide after the engine shuts down.



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Re: C/L length

Post  getback on Sun Mar 27, 2016 9:55 am

lol! lol! lol! I love it Kim that really gets me going to see you what looks like bouncing around form the plane cam , Just plane damn COOL man . OhBee good luck with your first in 50 !! do you have a helper to launch for you ? There are some threads here on stooge assist launching for your airplane . Yea we're having a PT-19 Fly'em if you got them I think its in Sept. bee sure to join in !! I had to build me a scratch balsa PT see if I can find a pic .. ... All I could find but did fly pretty good for being heavy and under powered (you know ) just don't try outside loops LOLOLOL !! getback I Love This Forum!
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Re: C/L length

Post  rsv1cox on Sun Mar 27, 2016 11:13 am

Yes, really neat, camera on the wing and pointing back towards the tail.  It's amazing how little elevator is required to do maneuvers  

Second video too, from the pilots perspective.  Loved the multiple loops.

In my younger days I used to do them over and over.  Breaks the monotony of just going round and round.  I liked to do inverted flights also, I was surprised how easy it is once you learn to think backwards.  I remember my profile P-40 (which I still have) was a master at inverted flights.

I never owned a plastic airplane until I joined this forum.  Still I have only "flown" if you want to call it that, the PT-19 that Ron has now.  

Thanks for those Kim, brings back memories.

Bob
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Re: C/L length

Post  Kim on Sun Mar 27, 2016 11:36 am

Thanks Guys!

And...as one final hijack of Steve's thread (or bait to further encourage his PT-19 flight)...here's some video of our PT-19 Fly-It-If-You-Got-It meeting in St. Louis.

I think most of the guys here would agree that a giant part of all this is the camaraderie of like-minded characters.  This demonstrates both the camaraderie...as Ron trains his bud, Moonie in the need for PT-19 vigilance, and characters...as St. Louis Dan flys with his teeth.



https://www.youtube.com/watch?v=ow4Zeqeqqjc
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Re: C/L length

Post  RknRusty on Sun Mar 27, 2016 2:14 pm

Do some turning, as in dry-flying in the house. Don't fall over a foot stool. That'll get your inner-ear used to turning. It does not take long to defeat the dizzies. And yes, though the PT came recommending 25', 35' is best. Any more than that will give you trouble controlling it, especially if there is any wind. You'll need a short grass or sidewalk runway to help get it airborne.
Good luck! I'm awaiting your flight report.
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Re: C/L length

Post  OhBee on Sun Mar 27, 2016 5:19 pm

Thanks guys! I'll keep it at 35 ft. or so and see how it goes! I have nowhere to take off from the ground around here...which I'd prefer. As I recall hand launching never panned out too well in the past! This plane is an old one with a Babe Bee and a R/H prop. It DOES have rudder and engine offset though. Should it also have an outboard wingtip weight? I only ever got one decent flight out of an old WenMac I had because it ALWAYS came in on you when hand launched! I think I got rid of that one to an unsuspecting neighbor kid!
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Re: C/L length

Post  OhBee on Sun Mar 27, 2016 5:22 pm

Oh...and I have the engine pitch adjusted one notch up from "beginner". That SHOULD slow it down a bit due to angle of attack on the wing. All we need here is some decent weather for a change!
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Re: C/L length

Post  OhBee on Sun Mar 27, 2016 6:22 pm

Just got a chance to watch the videos. I didn't even know you could do a loop with those things! I couldn't even pull off a wing over with my old lil Satan...after 4 major repair jobs it was history! Then I built a Jr Satan and put a big honking Ohlsson and Rice on it. It never got flown and was also abandoned in a move years ago. Man I wish I would have hung on to that stuff now! I just got tired of moving stuff around I hadn't used in decades. The planes all got left in the attic of an old shed where I lived 28 yrs. ago. Wonder what the odds are.....naah.
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Re: C/L length

Post  Kim on Sun Mar 27, 2016 7:00 pm

OhBee wrote:Should it also have an outboard wingtip weight?  I only ever got one decent flight out of an old WenMac I had because it ALWAYS came in on you when hand launched! I think I got rid of that one to an unsuspecting neighbor kid!

I've heard that some of the later PT's had a tip weight molded into the right wing, but have never seen one. I think gluing a penny under the outboard tip is a good idea...surely doesn't hurt anything.



Hand-launching one of these plastic sleds is dicey, because it's hard to throw them hard enough to get them flying, and still do it with some control. Some plywood sheeting can be used as a runway (I went shamelessly dumpster diving for the old paneling I use in the front yard). While it's a little pricey, a slab of foam insulation makes a great portable runway (though you got to guard against dim-witted friends who try walking on it).

You can cut two four-foot lengths and 'hinge' them with strapping tape, to unfold to an 8-foot runway.


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Re: C/L length

Post  OhBee on Sun Mar 27, 2016 7:15 pm

8 ft. enough to get airbourne? I was thinking of the plywood trick...not much for level ground around here! Maybe 3 eight footers with a ramp off the ground a ways at the end. Carrier takeoff!
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Re: C/L length

Post  Kim on Sun Mar 27, 2016 7:31 pm

OhBee wrote:8 ft. enough to get airbourne? I was thinking of the plywood trick...not much for level ground around here! Maybe 3 eight footers with a ramp off the ground a ways at the end. Carrier takeoff!

Yeah...wasn't thinking about a slowed-down PT which might need more. It is easy to put a brick or block of wood under the end to give it an upward boost. I'd also forgotten to allow for the extra length of the pegboard stooge I use when flying alone...which adds a couple more feet.



If the yard is mowed close, there's good chance that the plane will still launch.
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Re: C/L length

Post  roddie on Sun Mar 27, 2016 9:10 pm

A couple pieces of old carpet over-lapped might work for a runway (easy storage too.. just roll them up). How about a carpet runner? Another thing I've used for little wheels is tar-paper. You'd be surprised at the things you can find.. that you might already have.

If your flying area is small and has obstructions within 10 feet of your circle-diameter, you can stake-down the lid from a plastic pail at center-circle. It gives you a reference you can feel with your foot. It's easy to wander off-center not realizing it.. and smashing into a tree branch.. like I've done.. Shocked

A pin-stooge is easy to make. Here's an old one that I made.. and it's about as simple as you can get. Spring-steel music-wire and wood-screws into a plywood plate staked into the ground.



Those are aluminum gutter-spikes through angled-holes for using on a grass field. For asphalt.. mount it to a 2' x 4' sheet of paneling or pegboard (like Kim's) which should hold a small 1/2A model like your PT19 just fine.

This one below is a little more sophisticated.. and uses a compression-spring, flat-washer, music-wire pin with a loop formed for the pull-string, a guide-tube, landing-gear straps, small screw-eyes and a wheel-collar. Notice that either of mine have a raised plate for the pin-mechanism so it goes through the center of the screw-eyes.


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Re: C/L length

Post  NEW222 on Sun Mar 27, 2016 9:19 pm

Not my topic, but thank you roddie for your stooge pictures and descriptions. I now have something east to build.
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Re: C/L length

Post  OhBee on Mon Mar 28, 2016 1:12 am

Thanks guys!....some great ideas! Should keep me off the streets for awhile! Wink let the scrounging commence!
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Re: C/L length

Post  stuntflyr on Mon Mar 28, 2016 3:13 pm

I can't add much more to the conversation that hasn't already been said and well about flying the PT-19. I love the video of the group of PT-19 flyers at Buder park. Dan McEntee, the man flying one in his teeth is an Expert Stunt flyer and was my flying buddy during my 8 years in St. Louis in the 90's. Great guy and a very good flyer, builder and fabricator.
Here's my friend Dan in action flying Stunt.
Chris...
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Re: C/L length

Post  Kim on Mon Mar 28, 2016 4:38 pm

He's also got a bodacious collection of EVERYTHING classic that'd just about cause a guy to pass out !
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Re: C/L length

Post  Cribbs74 on Mon Mar 28, 2016 4:48 pm

Kim wrote:He's also got a bodacious collection of EVERYTHING classic that'd just about cause a guy to pass out !

I'll second that! A genuine good guy, he still has that Shark .45 hanging up in his garage.

Ron
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