This page contains a Flash digital edition of a book.
FanFacts H


ello again! Well, it must be June, and that means nasty forest fires in or around Colorado Springs, CO. Last fall, I had mentioned my penchant for list making, and hypothesized your neighborhood: the one with one road in, no other way out. Well, I’ll say no more than be ready to bug out in a moment’s notice! We all envision a fire starting in some forested area, and over the course of several days moving towards our neighborhood. Unfortunately, it was catastrophically demonstrated last week that in areas where our housing has moved into the forest, and with drought conditions, a fire can consume vast acreage, houses—and people—within hours from the first flame of ignition. We will never know the true reason that a fellow PPRC member and his wife were still load- ing their car when they were overrun by a 2500° flame front, but please prepare a bug- out list of things absolutely needed so you can rapidly get out of harms way of any nat- ural disaster. I, like most of us, used to think this kind of “stuff” only occurs some place else, to people I don’t know … ’nuff said. Moving on a bit, there has been a long running thread (130+ pages) on RCGroups concerning Hobby King’s L-59 edf (www.rc groups.com/forums/showthread.php?t=166 1261). A few have had luck, and many have been frustrated, expecting things to work, and fly, as designed/packaged. How- ever, any of us who have built almost any ARF from China realize that, frequently, significant modifications are needed to al- low it to perform to our expectations. En- ter Rich Uravitch, no slack when it comes to designing his own models, nor modify- ing an ARF.


It seems that the vast majority of posters in the thread wanted the Albatros to fly on 10S or 12S Li-Po, frequently on the ques- tionable Change Sun fan unit, which result- ed in an amp hungry and heavy airplane. Rich took another tack, powering his with a 6S “Dr Mad Thrust” fan unit, also from Hob- by King (to me, all of the aluminum fans look like the RCLander unit), which comes with the fan and motor already mated, bal- anced and ready to go. Additionally, he


by greg moore You can reach Greg Moore via e-mail at jetflyr@comcast.net


PHOTO: RICH URAVITCH


The Hobby King L-59 sits in the Florida sun waiting for Rich Uravitch to strap in and go for a ride. A fiberglass fuselage with built-up wings and tail makes for a nice flying airplane when kept light.


moved the fan unit forward a whopping 4.5 inches and made new ducting for it. With a few other modifications/massaging of the model, he came in at less than 8.75 pounds, which on a 6S, 5000 mAh battery, gives pretty darn good performance! To prove it, Rich posted a video of a flight on YouTube at: http://youtube/dLMC9CjJpu8. He also shared some photos with us and the follow- ing, very telling comment: “It is a really nice flying machine; very honest!” Since I’ve had a thing for this venerable Czech trainer, I think I might need to have another project! Still on the topic of planes I have a thing for: Rich has enlarged his twin 70mm S-3 Viking for 90mm fans and has flown it. With the enhanced visual appeal of a larger air- plane (as well as the potential for lighter wing loading) this has my attention, and I think it will have yours as well! Now for a video, Rich! Please?


Yet another successful “own-design” needs to be checked off in Mike Kulczyk’s log book—with several successful flights on his FJ-1 Fury at the hands of Steve Ellzey. Orig- inally anticipated to have a P80 turbine for power, Mike changed his mind and is now powering it with a JetFan 90mm fan unit turned by a HET 700-68-1500 motor on 8S. Yes, this ugly, tubby little fellow was the first of the line leading to the sleeker FJ-4 Fury and F-86 Sabre, so I guess we need to be careful about criticizing our forebears!


Being basically a P-51 wing mated to a fuselage wrapped around an under-powered jet engine, I suppose the FJ-1 didn’t have a chance at sleekness, nor greatness, but for- tunately this ugly duckling led to some swans. Mike (and now we) have discovered that the power of the JetFan needs to be thought about when designing intake ducts, since he had a collapse of his on short final. Remember, this is not your grandfather’s edf! I can bet that by the time I see this plane in September that Mike will have re- done the intake ducting and painted her, and I’ll share my report with you. Finally, Dick Sarpolus shared a few pho- tos with me, the first being his original Jet- ster from way back in 1979 which was pow- ered by the Midwest/Kress fan unit and a .40 engine. Later, he down-sized the design for a .20 engine and designed a little F-16 for a .049 engine. A few years ago he de- signed the much larger Discovery Jet for turbine flying but has gone back to more simple and relaxed flying with his edf Cougar, Panther, Phantom and Sabre. Looking at the Panther (another on my “to do” list) with its simple plate fuselage makes me go hmmmmm ... I think I need to build one in order to do some schoolyard flying after work!


Since I have a lot of photos, that’s it for this time around, so until next time: fly safe, and trust in thrust!


PHOTOS: RICH URAVITCH


Let’s go cloud surfing! Rich Uravitch’s L-59 (above left) is ready to play. His Dr Mad Thrust 6S setup provides nice power and a great sound at a light weight for the system. In order to get the nose unit to retract within the fuselage completely (above center), Rich reversed the gear and strut. Sometimes


24


modifications are needed to make things work the way we want them to. The original bulkheads (at the rear of the motor fairing) were removed and reinstalled with the fan unit 4.5 inches further forward to help with c.g. issues. Notice the custom intake (above right) to optimize Rich’s 6S setup.


JULY 2013


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68