stunthanger.com

General control line discussion => Open Forum => Topic started by: Peter Nevai on September 30, 2017, 12:09:32 AM

Title: Boeing 727 for CL
Post by: Peter Nevai on September 30, 2017, 12:09:32 AM
You may recall the B58 Hustler my dad built back in the 1970's posted here earlier. Unfortunately the 8mm movie footage of it in flight was lost over the years. After much searching through hundreds of family photos I found a couple of snapshots of the 727 he built (I did the covering) in flight. The model had an RC OS .20 engine for power and had throttle control via a 3 line Roberts setup. It had mid span flaps and working T tail elevator (Never tried any aerobatics with it though). The other unique thing was that the engine was installed in the outboard wing leading edge with the tank installed in the outboard wing. It had cabin windows and used LED's to light up the inside. It looked really cool and the model flew very well. I did powered landings, and unassisted take offs and touch and goes, it had a wheel brake on the nose gear which kept the model stationary when full down was applied.

I wish I still had that model, alas it suffered too much hanger rash being moved and stored over many years. But my dad was never the one to shy away from building unique CL models. He also did a FU4 Phantom jet that was never successfully flown.

This photo was taken at the field at Flushing Meadow Park NY. (As with all my Dads creations I was the pilot)
Title: Re: Boeing 727 for CL
Post by: Dennis Leonhardi on September 30, 2017, 01:25:10 AM
That is really cool.  Tell us more about the F4?  Photos?

Dennis
Title: Re: Boeing 727 for CL
Post by: Paul Taylor on September 30, 2017, 08:20:38 AM
That is so cool!!! 👍🏼

Thanks for sharing.
Title: Re: Boeing 727 for CL
Post by: Avaiojet on September 30, 2017, 08:33:31 AM
Pete,

Interesting stuff. Are you digging up more old photos?

CB
Title: Re: Boeing 727 for CL
Post by: Dennis Leonhardi on September 30, 2017, 08:33:57 AM
Question for the electric gurus: could you power this with a couple of ducted fans and get reasonable performance/duration?

Dennis
Title: Re: Boeing 727 for CL
Post by: Peter Nevai on September 30, 2017, 06:19:31 PM
That is really cool.  Tell us more about the F4?  Photos?

Dennis

Unfortunately I have not yet located the photo of that model. I am net even certain that there was one. It was on the 8mm movie footage which has been lost to time. I recall it had a foam wing the fuse was also partially foam with a 1/32 molded balsa sheet skin. The problem was that with the wing sweep we could not get the CG right. It ended up way too tail heavy and it crashed on the maiden flight. My dad fixed it but it ended up too heavy and roll inwards and crashed again. It did have the an-dihedral stab. See my dad insisted in keeping the wing profile like the real thing and because of that we could not get a proper lead out position and the CG always ended up behind the lead outs. On the B58 the big assed Fox 59 and the long nose put the Right at the front lead out. So even as most of the model was in the rear the balance worked out. The B58 however had to be screaming along to get airborne and you landed really hot once the engine quit, but it worked.

The 727 had a wing shape that just worked out really well for a CL model. It is wide at the center and most of the sweep is there which allowed the engine to be mounted in the outboard wing. Further out it tapers and the sweep angle is not so pronounced and allowed the bell crank pivot to be behind the CG. As you can see from the photos the little model flew level and straight on the lines. With the engine roughly pointing roughly 30-40 degrees outwards line tension was never an issue.
Title: Re: Boeing 727 for CL
Post by: Peter Nevai on September 30, 2017, 06:31:23 PM
On another front, I did once convert the Sterling King Cobra RC model to control line. Complete with a GI Joe in the cockpit. It was powered by a Merco 61 engine. I kept it with the removable wing as otherwise it would not fit in the car. I had throttle control on that one as well. No one ever told me not to do 3 consecutive loops using a 3 line set up. So after some wing overs and lazy 8's I went for the loops and after loop #3 the lines got tangled up and it kept on looping right into the ground. It was a bad day all around.... HB~>
Title: Re: Boeing 727 for CL
Post by: Scott Richlen on October 01, 2017, 01:53:39 PM
Were there plans drawn up for any of these?

IMO this is the stuff that we need to do more of to capture the fun of CL flying.  Why should Banjock have all the fun!  No fair, I says!!
Title: Re: Boeing 727 for CL
Post by: Russell on October 02, 2017, 09:14:01 AM
Were there plans drawn up for any of these?

IMO this is the stuff that we need to do more of to capture the fun of CL flying.  Why should Banjock have all the fun!  No fair, I says!!


This may be it or at least close:


Aeromodeller Annual 1971-72, page 87 --> https://rcbookcase.com/details.php?publication_id=336


727 Astrojet plan --> https://aerofred.com/details.php?image_id=97187

Title: Re: Boeing 727 for CL
Post by: Michael Boucher on October 03, 2017, 12:26:44 PM
Hi Peter, Do you have the plans for the 727 still? Thanks, Michael
Title: Re: Boeing 727 for CL
Post by: Dan Berry on October 03, 2017, 09:40:55 PM
https://stunthanger.com/smf/12-a-building/727-at-small/

It's a bit ... SMALLer .... than the other one but it does look good.
Title: Re: Boeing 727 for CL
Post by: Peter Nevai on October 05, 2017, 09:18:38 PM
Hi Peter, Do you have the plans for the 727 still? Thanks, Michael

This model was not built to plans, believe it or not my dad scratch built this using general outline drawing he sketched and using a Plastic Model by Monogram or Aurora for reference. The idea for the wing mounted engine came from a profile CL model design from the 1970's. I cannot recall the name or the designer of that profile CL model and try as i might could not find any reference to it online. I recall that my dad did build that Profile CL model that mounted the engine on a Swept wing design, and dam if that little model would stunt. It flew most like a BiSlob and I could get it to Saber Dance, and just about hover and flip back and fourth. I wish I could locate that design because that is the CL design that the 727 was based around except for the being a scale model of the Boeing 727. Perhaps someone here in the Stunt Hangar community remembers the CL model that featured a engine mounted on the leading edge of a swept wing design. I do recall it was not a big (35 or more ) sized model, It was a profile and perhaps for a 15 or so size engine.

How about it guys? Anyone remember that design from the early 70's??