Electronic Second Wind 92-1
Second Wind 92-1
The NEWSLETTER For Those Who Keep It Up With Hot Air!
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The Rattle of the Saber!
It may have started as a hardly audible rumble, but now the rattle of the Saber is becoming a thunderous roar all around the country! 1991 was the first full contest season for the Saber and it wiped out the competition wherever it was being seriously flown! On the East Coast, Frank Stickle won the season championship of the Capitol Area Soaring Society (CASA) ending the Season flying his Saber exclusively. Earlier in the season he flew both his Saber and his Thunderbird. Charley Wells and his Lovesong placed 2nd and Jack Cash flying a Windsong much of the year placed 3rd!
It seems that the fellows on the East Coast do not feel that the Falcon can float out the air-times necessary to be competitive. Desperate to disprove this belief. Tom Dickey is rumored to have expertly landed his Falcon in a pond. Just after touch-down, Tom was reported to have triumphantly ejaculated see, it does too float! I can well imagine the enhancing effect that this valiant effort to resuscitate the local reputation of the Falcon, had on Tom's don't be a Dickey reputation. It is also rumored that Tom has a good sense of humor. I sincerely hope this is true.
As a further point of interest. truth in the media forces me to expose a serious establishment cover-up. CASA is the home club of the Magic factory. The Tragic appears to be noticeably missing from the club season winner's circle. Bob Teseo won the Season Championship of the Long Island Silent Flyers in NY with his Saber. Robert Teseo Jr. placed 2nd with his Lovesong. (See Robert's letter under the Letter Rip, section.) The season championship of the regional North West Soaring Society (NWSS), encompassing 5 states and western Canada, was won by Dave Banks and his Saber. This dynamic duo even won the big regional year-end NWSS Championship Contest. In spite of an undocumented California state quarantine against Sabers, entailing border inspections (they say they are trying to protect their fruits and nuts), smuggled Sabers have been making serious inroads. Ken Raymond hung up his Falcon, after an early season switch to the Saber, and went on to win both of the big season club-championships for the North County Clouds (NCC) glider club. He won most points for 10 contests as well as most points for the best of 7 contests. Not content with local fame, Ken flew in the December 1991 Torrey Pine Gulls contest with his Saber and took first over all Yes, the wheels of progress grind slowly when the ruts are deep but The times, they are a changing. The performance of the Saber is shouting above the tips-up media mythology. If you have a Saber and want to have the Center of Gravity at that magic location, try putting it 1/8 behind the rear edge of the main wingrod. If you have been flying with the CG. at some other location, I think that you will be amazed at how the Saber really comes alive at this C.G. location. It climbs right through the competition in marginal lift and it circles and thermals like a dream. Try it. You'll like it!
What's New?
I972 to 1992, this is our 20 year anniversary in the business of designing and selling nothing but high-performance, multichannel sailplane kits? No other exclusively glider kit manufacturer has ever lasted more than a few years! Among our other accomplishments, we established the glider-control-system standard that the world is presently using and we had it all to ourselves for many years! It began with the Todi in 1972 and reached its final form with the introduction of the Windsong in 1982!
The exciting Pivot news is that it has been selling like crazy! We are in the process of bringing out a Pivot with the SD7037 airfoil, made famous on our Saber and Anthem. The good news is that the wing kits for the new Pivot can be used with all of the Pivot kits that we have sold throughout the years. The jury is still out in the area of super-light lift between the Pivot using the excellent E387 airfoil and the Pivot using new SD7037 airfoil. The turning and handling of the SD7037 Pivot appear to be awe inspiring. The same is true of L/D, the follow-through in maneuvers and the higher speed performance. We will probably end production on the E387 Pivot when the SD7037 version comes out in late January. We are not only changing the wing airfoil, spar system and sheeting, we are making improvements to all aspects of this remarkable bird! One thing that we will not change is the fact that the Pivot is the one top performing sport thermal/slope glider that can be taken with you anywhere because it quickly and totally disassembles. It will fit into a box as small as 2 x 7 x 37 inside measurements! Not bad for a plane with a wing span of up to 72! Try putting your one-piece-wing dedicated slopers in such a box or in such light slope lift or in a light thermal! In heavier slope lift, the SD7037 Pivot will dazzle even the most jaded sloper.
Remember, Pivots have even been winning 2-meter thermal contests! While it can win in other gliders' classes, there is no other thermal or slope glider in the Pivot's class. The Mighty Lovesong continues to trounce the latest and greatest designs of the competition. Here is just a sampling of the 1991 wins: Rob Teseo placed second only to a Saber for the season points championship of the LISF club in Long Island, NY; Ron Lenci placed first in season points for the Modesto R/C club in Modesto, CA; Charley Wells placed 2nd for the season in the CASA club in MD; George Voss beat all comers for the COSA season championships (see Letter Rip) in Oklahoma City, Oklahoma, and Erik Eiche won top honors for the Kestrel sailplane club in Vancouver, BC. Due to the startlingly high demand for Lovesong kits, we have not yet discontinued them. In fact, with the apparent wide and loyal following that the Lovesong and the tripped E214 airfoil have established, I may even upgrade the kit to obechi sheeting etc. and continue it in the line. No other high performance glider with anywhere near its maximum L/D can slow down like a Lovesong for landing! No other state-of-the-art performing glider is set-up to easily be flown full function without a computer radio!
Saber vs Anthem
Unwittingly, I find myself flying on the wings of a dilemma. With the Saber out-flying all of the competition's designs, why did I confuse the issue by coming out with the Anthem? 1 have created my own worst competition and forced potential customers to choose between the two top performing open class thermal competition gliders available. While the Anthem has only been out for a few months ...too late for the 1991 contest season, it has already created a legendary reputation as being the pinnacle of soaring competition hardware. For example, Shawn Lenci had the first Anthem flying in California. He completed it in September (about three months ago) and has already won four 1st place trophies with it! Everyone confirms that the Anthem mysteriously has a much
quicker roll response and feel than that of our Mighty Lovesong. For some reason, it defies all slow handling rules associated with the performance advantage of a beautiful, high-aspect-ratio wing. The Anthem retains the unequaled ability of the Lovesong to have a slow and controlled landing approach, while the increased speed and ranging ability make, simply, the best package in soaring competition. Everyone is raving about the Anthem's handling. Even my friend and tormentor, Al Doig, who has flown about every plane I ever kitted, says that the Anthem is the best plane that I have ever deigned. So now you have it. If you plan to fly many speed runs in conjunction with thermal competitions, you need the Saber. If you require a fully pre-formed fiberglass fuselage or prefer a 3-meter sized ship, then the Saber is for you. On the other hand, the Anthem's refined taco shell style fiberglass fuselage has received many plaudits from folks who had not expected it to build so easily and be so strong and light. If you do not mind spending an extra 4 hours of fuselage building time to save $16 in the kit cost, gain a stronger, lighter and more easily repaired fuselage and gain the increased ultimate performance that the longer wing-span can offer, then the Anthem is the ship for you. If you still cannot make up your mind, I am considering kitting a Rapier (at least on a limited basis) which will combine the Saber fuselage and the Anthem wings. As another twist, the Anthem/Rapier wings can be put onto existing Saber fuselages for the simple drilling of another (more forward) wingrod hole in the fuselage. Naturally, since the Anthem wings do not have the swept LE of the Saber, the C.G. location must be shifted forward on the wing root. It should be near the center of the new wingrod location Our exclusive taco shell fuselage is accepted as being the easiest fiberglass fuselage to repair! It might take you an extra four hours to build but it may well save you many more hours in future repairs and maintenance. These fuselages can be easily repaired so that the damage is invisible. You do not see the typical big lump fiberglass bandages around the tail-boom of one of our taco shell fuselages, that you see on nearly any conventional fiberglass fuselage that has seen much action. Many nine-year-old Windsongs that have seen thousands of remarkable flights, still look almost new! ________________________________________________________________________________
Letter Rip
Oct. 15. 1991 - Bob. well I finally did it! I waxed 'em all. We had a short contest season this year but me and my Lovesong won all of them. I finished first in COSA overall for '91 beating Texas Tom Williams (Falcon). Tom did well at this year's NATS trophying in four events I know of. Tom only lacks his eight hour slope flight for LSF Level 5. He's had two flights of over seven hours. I also beat Steve Hudson (former Windsong flyer) with his Synergy. Sandy Hay is an LSF 4 flyer, no slouch for sure- What can we say. again the Lovesong floats to the top!
...Any progress on the 2m/standard? I'd like to do a review for Model Airplane News on it when you get it ready. Thanks & Thermals, George Voss - Oklahoma City, OK
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August 14, 1991 - Dear Bob, this winter my father purchased a SABER kit from you as a sport/knock-around plane, thinking that it could never be better than THE MIGHTY SONG.
I however, wanting something new purchased an (Un)Magic, because it seemed to float better than a SONG. You cannot know how Pee-Oed I was when the lead-sled looking Saber out-floated me! Well, I soon got rid of the Magic (knowing the true Magician was the salesman) in favor of my old Song (just an OLD FASHIONED LOVE SONG). The first contest of the year went great, easy 1st followed closely by my father and the SABER. Second contest I took second following closely behind my father's SABER. Well let's just say I stopped singing, as the point spread widened. Anyway, my father let me fly his SABER the other day. For the first time, I feel I have found a Great airplane! This plane truly does float like a butterfly and sting like a bee! With this airplane you aren't afraid to try anything! This airplane was truly born to fly! From low level thermals to long duration to any aerobatic maneuver you can name! (Although it doesn't do a good snap roll when set up for thermal duration flying.) On another day, my father, his friend and I passed the transmitter around on one flight for an hour and forty five minutes! Sorry I doubted you! Rob Teseo - College Point. NY. P.S. Why Anthem? Why not True Love, or Real Love, or Saber Song, but then again. SABER goes against your musical derivatives. P.S.S. (Bob Teseo Senior's addendum to the letter) Now four wins, one 2nd, one 3rd for the Saber. Bob, with the contest season 2/3rds over, the Saber has locked up 1st place in expert for the year in the Long Island Silent Fliers.
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July 29, 1991 - Dear Mr. Dodgson, many thanks for promptly sending my missing Lovesong plans, which arrived after 15 days.
Of your models, I have seen Todis, and one unflown Caliente. One of the country's leading glider pilots Mr. Rafn Thorarensen won (if his memory is correct?) the Icelandic Nationals three times in a row with his Todi between 19771980. He was very happy with his model. Having studied aerodynamics from my early teens, I realized the advantage of a variable trailing edge in your Maestro advertisements in my very late teens about 12 years ago and always longed for such an aircraft. Better late than never. With best wishes, SveinbJorn Olafsson - Reykjavik, Iceland. ________________________________________________________________________________
August 15, 1991 - Hi Bob, I received the Second Wind last week and there is a big problem. I read it too fast! Now there is nothing else to read ...No really, it was great. I only wish you could send them more often.
I do have a question for you, though. I don't remember receiving the 91-1 issue. Do you think it would be possible to get a copy of it? I have moved and the mail has been getting to me but for some reason I didn't get the 91-1 (new address below). I have only been moved away from the area for close to a year now and I can already tell that I am going to have a difficult time keeping tabs on what you and the SASS group are doing. The ANTHEM looks great. I just wish I would be ready enough to get a LOVESONG (both skill and $$) before you got rid of them. Oh well, I will just have to look forward to the ANTHEM now instead. I am currently having fun with the little Pivot and I am considering getting another one (both 60 and 72 wings). It seems to go just about anywhere. It looks, though, that with the newer planes coming out that I will have to invest in a computer radio. So, that is going to cut into my plane budget. Anyway. Bob. it was great to see the Second Wind. It seems that after I just about get tired of searching through all of the Model magazines for articles that will satisfy my interests, along comes the Second Wind and really helps! Thanks Bob, Craig K. Coles - Springville, UT ________________________________________________________________________________
August 20. 1991 - Dear Bob, thanks for your letter in reply to my inquiry re Saber wing cores. I think I11 order the entire Saber wing kit plus the prebuilt spar.
I had already thought of placing the wing inverted in the top cradle to insure the proper upper contour as you suggested. Although I do not recollect exactly the way I did it on the wing I built, I am inclined to think that I did it right side up in the bottom cradle. I do not vacuum bag. I have used the tape only on my ancient Camano (built about 9 years ago) and have used epoxy on the Pixy, 2 Windsongs and a Lovesong since then with satisfactory results. I feel that the epoxy considerably strengthens the wood with no weight penalty if properly used. I used tape on the Saber wing because obechi is porous, and I thought it might absorb too much epoxy; but on several test scraps, the indication is that it would be quite satisfactory, so I am inclined to go that route on the cores I am now ordering. You thanked me for supporting your products; I have built a great number of Sailplanes and yours are simply the best, everything considered; so your products are easy to support. There are not a lot of sailplane enthusiasts here; the latest is Terry Repp. I talked him into a Lovesong, and he did a fine job on it and is enjoying flying it immensely. He built it without the trip. but he added the trip later. The performance improvement with the trip was very noticeable; he had to add considerable nose-down trim, which seems to indicate a lift increase, plus the slow-flight handling is very much improved. My Lovesong was built with the trip on it from the start. Continued success to your endeavors. Cordially, Conrad Lesh - South Bend, IN ________________________________________________________________________________
August 19, 1991 - Dear Bob, I thought you might like some photos of the first Australian Saber. I found the building quite easy and the instructions and plans easy to follow. To date I have had only one flying session and it flew straight off the board with only some elevator trim needed.
I am about to leave for two weeks in the U.S. on the 24th. So I hope to get in some flying in on my return. I will send you any contest results I may get. I have done some video on building. I will send you a NTSC copy at a later date when I have gotten some flying on the tape also. Enclosed you will find a sample of the covering I used. It is called Koto Leaf Ash. The film covering is profilm. Here's hoping for many good flying days ahead with my Saber. Regards. Trevor Broadbent - Matraville. Australia (another Dodgson convert) G-day from downunder! ________________________________________________________________________________
September 9,1991 - Subject: LeadGend. Bob, according to the attached letter that appeared in the BASS newsletter. the troops are getting frantic trying to figure out ways to stop the Legend in the landing circle. Why not try a Lovesong or an Anthem. Best Regards, Ken Troxell- Gaithersburg, MD.
P.S. Legends here on the East Coast are coming out 80 oz. plus! ________________________________________________________________________________
August 5, 1991 - Dear Bob. the following are for your consideration for inclusion in the Second Wind.
Tips-Up. Fad or Solution?
I had to find out for myself what was with the tips-up bit. So, I added tips to a well known design in the same manner as another well known design to see what results I would find.
The results were: a polyhedral-like model, very stable but at the expense of steady rail-like thermal turns and lack of turn capability in a down-wind situation. Dismayed at what I had done, I sawed off the tips-up and replaced them with normal wing-tips. Result, the aircraft turned on a rail and had plenty of roll capability, i.e. flew as a real aileron plane. Conclusions: 1) Tips-up is for aileron trainers and design them so that they are removable after training is completed. 2) Tips-up limit flap area which can be better utilized for slowing the craft for landing. Straight wings with dihedral allows the ailerons to be positioned more outboard, allowing for longer naps without the loss of roll control. 3) Tips-up allow for more ground clearance in tight turns close to the ground but waste wing area in all other regimes of flight. 4) Now, if I could only sell my tips-up kit which I bought before I realized that I could not extend the flaps, I would be happy! --Best Regards, Tony Bonanno Rancho Palos Verdes, CA. ________________________________________________________________________________
The key to popularity --telling Bob Dodgson How To Build a Saber --Part 1
as told by Al Doig
The Old Professor was in the 'Thinking Room when Yeti came bounding in, tripping over an old Lovesong wing and falling flat. OOps winced Yeti. I didn't see that wing. No matter. The Professor replied. You Sasquatch never look where you are walking, and you have such large feet. And. I do wish you would straighten up. You are beginning to look like some of those blurred pictures I've seen of some of your relatives - bent at the waist with head thrust out. Oh well, you're a good kid. Our chalk-talk tonight will be the natural finish of Obechi. I saw him in Alexander Graham Bell on TV the other night. The Yeti was anxious to show how much he remembered. Who on earth are you talking about? queried the Professor. Don Obechi, but I didn't know he died said Yeti with a puzzled look. Oh, for goodness sake, I'm not talking about Don Amechi. I'm referring to the obechi wood Dodgson uses to cover the Saber wings. and how to put a natural finish on your wings, instead of Monokote. Oh Anyway, the second topic is vacuum bagging. The Professor was trying to keep the conversation at Yeti's level. He was not succeeding. I guess you're not referring to the fact that ours needs a new one. Yeti ventured. No I'm not referring to a vacuum cleaner bag. The Professor was a bit short. First, let's keep this discussion confidential.' said the Professor as he strode to the bust of Bob Dodgson, standing on its pedestal in the corner. He swooped up a pair of ear muffs and covered Mr. Dodgson's ears. Now we can proceed. For those fortunate enough to miss the last episode in Second Wind, the Old Professor is Professor Emeritus from Tijuana Tech. Yeti is a young Sasquatch that the Professor found in the brush near Walla Walla and is now raising. Now may we proceed? There are those who are tired of the same old Monokote (or Solarfilm) finish of their sailplanes. It seems a shame to cover up the nice woodsy look of obechi. The problem we are fighting here is weight. Yeti sneaked a sly little smile. He knew the Old Professor was also fighting a little weight problem - but not nearly hard enough. Solarfilm weighs roughly 1/4 ounce per square foot. The Professor continued. This means you can cover a Saber Wing and stab with 3.5 ounces of Solarfilm. This also provides a smooth, waterproof surface - hard to beat. Obechi is an open grained wood that when wetted, will wrinkle like a prune. Yeti made a face. He didn't like prunes. So, we must fill the grain and provide a smooth waterproof surface, with not much more than 4 ounces to work with. For guidance, I turned to my friend Jim Luken, a champion hand-chuck glider person. We use Japanese tissue to fill grain and give a smooth surface. Jim replied to my inquiry. So. following Jim's instructions. I sanded the obechi smooth - being careful not to sand the thin wood more than just smooth. Next, I brushed on one coat of Sig Nitrate Dope, unthinned. The reason for not thinning was to inhibit penetration. Nitrate Dope will eat foam alive. I think this may have been unnecessary as this wing used epoxy to stick the obechi. As this is scraped onto the obechi, I think it must form a pretty good barrier to penetration. Anyway, after drying, I lightly sanded and applied another coat thinned 1:1. The reason for the Nitrate Dope? - to serve as adhesive for the layer of Japanese tissue - which goes on now. A loud snort indicated that Yeti was dozing. The Old Professor glanced at the bust of Bob Dodgson, in the corner on it's pedestal. He thought he detected an unusual curl in the statue's lip. I wonder if those earmuffs leak Good Japanese tissue is not easy to come by, nor cheap. One must go to a house specializing in free flight supplies, and hope for the best. It pays to have a friend like Keith Finkenbiner, who formerly had a good supply before I tapped it. The next step is to trim a piece of Japanese tissue to approximate size. The tissue is laid on the obechi and smoothed down. Next, Sig nitrate dope thinner is brushed carefully on the tissue. Now, the tissue is worked down onto the surface with the fingers. Some micro-wrinkles will appear and are smoothed down with the fingers. You can feel the nitrate dope soften as you smooth the tissue. Keep working the tissue with the fingers until the surface looks perfect. The nitrate dope provides the adhesive to stick the tissue. You may trim the tissue to the edges of the wing as the purpose is to fill the obechi grain, not provide strength to the wing. It is pretty obvious when you are through. The tissue is really flat to the surface, with no bubbles or wrinkles. The next sheet is carefully butted to the first, avoiding an overlap. A small gap between sheets will be filled with adhesive and finish coat. An overlap will show in the final finish as a white line across the wing - not serious, but offending to the eye of the builder, but not many others. The wing is then finished with brush coats of Lacquer Sanding Sealer. I used a product from The Standard Brands Paint Co. called Benchmark. Though I brushed on four coats, I think two is enough. I tried to keep a record of the weight gain with each finishing step, but found that with this type finish, weight changes hourly for a couple of weeks. I do know the following: the total weight gain of the finish, with the four coats of sanding sealer plus the 4 push rods and covers, hinges, wing skids, screw eyes, circuit board horns, and decals added just over 4 ounces. So, the total finish itself was about 3 ounces. So, we achieved our weight goal, There is always a 'however'. However, I must warn that a smog colored aircraft against a smog colored sky begets visibility problems. I cured this with a light spray of gloss black auto lacquer on the underside of the wing. I applied it in 'Harley Michaelis' type big black stripes. The weight gain is almost immeasurable and visibility is much improved. Yeti was snoring with a resonance which rattled the dishes in the breakfront cupboard, next to the fireplace. The old Professor glanced at the bust of Bob Dodgson, standing in the darkened corner of the Thinking Room. He swore Dodgson's eyes were closed. Even though his audience was sound sleep, the Old Professor continued recording his thoughts on his old pre World War II wire recorder. One last suggestion for all sailplane builders is the subject of flap/aileron hinge material. It takes me about four hours to hinge the wings of a Saber with the strip hinges, made from covering material. A further problem is the poor adhesion to itself of many films. A wizard hinge is made quickly from a material called Frisket Paper. This comes in about a 2 X 2 foot sheet. Try to get 3M brand as it has the proper characteristics. Zip-A-Tone COPYZIP HIGH TACK is also good. In any case you want a high tack (sticky) film. Frisket paper is available from large art stores catering to people doing air brushing. It is used in masking for air brush work. Frisket Paper looks like a big sheet of Scotch Tape. To make hinges, just lay down a straight edge and, using an XActo knife, trim a 1/2 strip. Place the aileron or flap in exact position, with the hinged surface up, and tight against the wing. Saber ailerons hinge from the top, flaps, from the bottom. Peel the l/2 strip of Frisket from the backing, lay it along the full length of the hinge line, trimming to fit, and smooth down tightly. Lay the aileron/flap back against the top or bottom of the wing . Now, lay another 1/2 strip of Frisket Paper along the full length of the inside hinge line. This will not only provide a really tight hinge, but seal the hinge joint from dirt, which would loosen the hinge in time. So, in ten minutes you have a flutter resistant hinge that will last a year, or more. The Old Professor snapped off the wire recorder with a loud click. Yeti snorted and jumped up, looking wildly around. No, that wasn't a rifle being cocked. It was just my recorder switch. I guess I dozed off for a moment. Yeti said, yawning. Off you go to bed. We will finish the story of vacuum bagging tomorrow when you can stay awake. said the Old Professor with a kindly pat of Yeti's behind. Yeti gave the Old Professor a big kiss and stumbled down the dark hall to his room. Yeti certainly has a lot of facial hair for a child. mused the Old Professor. I wonder if the kids in Nursery School have noticed? HOWZAT! ________________________________________________________________________________
Polyhedralblindcitas
Reprinted from March 15, 1991 Aerial Boundaries - Mike Kirk, Editor
Open Class
by Frank Foster
... Hot News! I guess the success of the Falcon 880 has got my favorite architect from Bothell, Washington running scared. Word has it that he has given up taco shells, the Eppler 214 airfoil, balsa sheeted wings and his beloved AFART mixer. Bob Dodgson's new 121 span Saber uses a flapped Selig-Donovan SD-7037 airfoil in a effort to match the wider speed range of the newer competitive designs. Flap and aileron servos are mounted in an obechi skinned foam wing, which eliminates the slop associated with fuselage mounting. And wonder of wonder, the fiberglass fuselage is a fully joined layup. Apparently Bob overlooked the tiplets, or didn't understand their function. Rob (Maholic), you drew the Dodgson gift certificate. Go for it!
Medical Alert!
Lexington, Kentucky: Polyhedralblindcitas Is On The Increase!
by Bob Dodgson The soaring community has all but forgotten the dark years of soaring's great polyhedral plague that enveloped the country from about 1975 to about 1987. While there was a known and effective antidote to the disease, most victims chose not to take the cure. You see, the antidote was a double edged sword in the form of straight winged, multichannel aileron/flap gliders that offered a broader range of performance and handling capabilities. The other edge of the sword was that these gliders could not be flown successfully by many of those whose brains had been zombieized by the ravages of polyhedralblindcitas. As a result, most of the victims of polyhedralblindcitas continued bumbling and flailing around in the same narrow overhead window of the sky, through both lift and sink cycles year after year. The flying style often demonstrated by victims of polyhedralblindcitas can best be understood by visualizing a cork (or other appropriate solid object) bobbing around in a toilet bowl just as the flush valve has been opened. Suddenly, about 1988 everything changed! A few of those with polyhedralblindcitas accidentally took the cure and learned to master real straight winged gliders. They became so jubilant that many of their former fellow victims were enticed into venturing out and trying the cure. For a few brief moments of euphoria it looked as though the soaring community was about to get the upper hand over the old enemy... polyhedralblindcitas. Alas, it was too late for many. They could no longer make the leap required to break through into the more demanding and rewarding realm of high performance, straight-wing, multichannel soaring. Many of those who tried to conquer polyhedralblindcitas experienced the heartbreak of a devastating relapse. In fact, there became such a number of frantic, failed, flailing. floater flyers who dreamed of moving up to the slick, sophisticated, satisfying, soaring-solution offered by the high-performance, multichannel, straight-winged gliders that a whole new market was ripe for the harvest. Some clever people decided, What if we put ailerons and flaps on polyhedral gliders? We can tell the wretched souls with polyhedralblindcitas that polyhedral is once again a socially acceptable disease. Maybe we can even shorten the length of the bent-up portion of the wing a bit without going so far that panic will set in among the disease ridden victims of polyhedralblindcitas. Thus was born what may well become known as the purgatory class or the tips up class of glider. While rising above the cork in a toilet bowl polyhedral glider (as does methane gas) the tips up compromise glider cannot quite reach into the heavens to soar with those who have been able to master the straight wing and thus totally escape from the clutches of polyhedralblindcitas. Knowing the vicious effects that polyhedralblindcitas has on its victim's mental acuity, I can only shake my head in sorrow when I hear out-of-hand condemnations of gliders like the Saber for not being tips up. Perhaps if Frank Foster ever gets a chance to actually see and fly a Saber, it may offer him the wings to soar out of the clutches of the purgatory class glider and experience the joys of flying with the gods. But alas, thoughtlessly discarding the unknown without ever seeing or trying it is one of the symptoms of a mind disease-ridden with polyhedralblindcitas. Happily, those who have had the good luck to fly a Saber do not Foster Frank's polyhedralblindcitas tainted view. --Dr. Bob Dodgson ________________________________________________________________________________
Telling Bob Dodgson How To Build a Saber - Part II
as told by Al Doig
The Old Professor had just finished with the breakfast dishes. Putting the box of Bran Flakes in the cupboard, he addressed his next remark to the bust of Bob Dodgson, sitting on it's pedestal in the corner. At the checkout counter, yesterday, this really attractive lady asked me if the Bran Flakes were for my son. I replied, of course, madam, they are for my son' The Old Professor had just walked Yeti to the nursery school bus and was startled by Yeti bursting through the door straight for the bathroom. I reckon we better cut out the Bran Flakes. Now I'll have to take him to school myself. The Old Professor was getting a bit grouchy. Yeti made the trip to school on the handlebars of the Old Professor's bike. Taking his after-school cookies and milk, Yeti settled down for another lesson at the feet of the Old Professor. The Old Professor opened the story of vacuum bagging with another vacuum anecdote. In my undergraduate days at Tijuana Tech, I had a 1936 Ford V8 coupe. I decided to spruce up my pride and joy with paint. I did not have a spray gun, but my sister-in-law had a brand new vacuum cleaner, with a paint sprayer attachment voilà. I filled the jar with paint and plugged the hose into one of the vacuum cleaner's ports. After five minutes of spraying, no paint had come out. However, the level of paint in the jar had gone down. I took off the nice brand new vacuum cleaner hose and poured out the paint. I had, of course plugged the hose into the vacuum port, instead of the blower port. Was your sister-in-law angry? Yeti couldn't believe the wise Old Professor had done such a thing. Of course not. said the wise Old Professor; she just chuckled and came at me with a meat axe. Anyway, vacuum is a very powerful tool which we can use in sailplane construction to our advantage. When applying the skin to Saber wings, it is desirable to press down the skin to the foam core with an even pressure, regardless of what adhesive is used. There are many ways to vacuum bag a wing. The method I've found most satisfactory does not really involve a bag at all. If you go to your local home supply discount store and look for a Formica sink top, you will find a 6 footer for around $20. These have a turned-up splash barrier at the rear and a small hump at the front. In between you have a 22 x 6 foot perfectly flat Formica table that epoxy won't stick to and that is a perfect base for vacuum bagging. This base assures a perfectly flat wing. The Formica doesn't leak air so all you need is a single plastic sheet sealed to the Formica all around the edges. This forms the vacuum cocoon for the wing. Generally, the Old Professor put ear muffs on the statue of Bob Dodgson during controversial technical discussions. Today, however, he decided that perhaps the statue was capable of absorbing the discussion with out developing any more cracks. A glance at Yeti revealed that young gentleman was more interested in a comic book laying on the couch beside him than the Old Professor's dissertation. The Professor pretended he didn't see and continued to speak into his old WWII wire recorder. The first step in the bagging process is to make sure the foam cores are absolutely smooth. Any dent in the core will show up in the thin obechi. A really wizard product to fill with is DAP FAST-N-FINAL SPACKLING. Red Devil also makes a similar product. It is a nearly weightless spackle that goes on with a putty knife and makes perfect surface fills. Take special pains around the spar to get a perfect airfoil. Lightly sand and vacuum the dust off the surface. Now, I like a perfectly straight trailing edge and am willing to add a tad of weight to get one. I first epoxy a 3/4 piece of 0.007 carbon fiber flush [Al, I would make it flush with the wing TE as shown on the plans!] with the entire trailing edge of the foam core along the entire length, top and bottom. I then cut a 3 wide strip of medium weight fiberglass the length of the wing. This then is smoothed on the foam core, flush with the trailing edge, top and bottom. This is tacked in place using dabs of Hot Stuff UFO. So now we have a four layer laminate of carbon fiber, glass cloth and foam. The carbon fiber not only provides stiffness, but the trailing edge can be sanded down to the carbon fiber, leaving a knife edge that is protected from dinging by the carbon.
The top and bottom obechi sheets are trimmed to the wing outline. There should be only 1/8 or so protruding beyond the front of the foam core. The trailing edge is flush with the core [Once again, I would make the obechi flush with the TE location shown on the plans which is a bit beyond the edge of the foam core].
The bagging area should now be prepared. lay the foam core in its cradles on the Formica surface. We must provide an airtight seal between the plastic 'bag' and the Formica. I use a product called Tacky Tape made by Schnee Morehead Inc. 8835 Dice Rd., Santa Fe Springs CA 90670 (213-698-9735). This is a low temp sealer for vacuum bagging. It is a black, sticky material about 1/4 X 1/8 with a peel-off backing. This is laid around the periphery of the wing leaving about 2 all around. Another more common sealer can be used - ordinary plumbers putty. This is less tacky and harder to use. It must be rolled into a long continuous rope. it, however is easier to locate.
A soft 1/4, or so, rope is laid around the wing core periphery, between the core and the sealant. The purpose is to provide a path for escaping air, so none will be trapped. A full length piece of paper towel laid on top of the wing cradle will accomplish the same thing. The vacuum pump is put in place and the hose run into the vicinity of the rope, or the paper towel. The sealant is looped around the hose to seal the vacuum. Using epoxy adhesive really pays dividends. The wing is really rigid, especially in torsion. Care must be taken as epoxy is heavy. My epoxied Saber is 4 ounces heavier than the one using transfer tape. It is, however, a better wing - very solid with a really straight trailing edge. I use EZ LAM 1 hour epoxy, from Aerospace Composites (714-250-1107). This is also where the carbon fiber comes from. Mix up 3-1/2 oz. of epoxy. Pour half into another paper mixing bowl for the top sheeting. The reason is to reduce the epoxy mass to prevent an early reaction. A plastic spatula used to apply house wallboard tape works really well to spread the epoxy. Starting with the underside of the wing, the trailing edge fiberglass is wetted with epoxy. It is then blotted dry using toilet paper. Use a minimum of epoxy and really press out the excess with several applications of blotting. Now apply the epoxy to the bottom sheeting. When I say to put it on and then scrape it all off, I'm not kidding. The obechi should be laid flat and pressure applied to the spatula. Keep scraping the epoxy off the spatula into the bowl. The more epoxy in the bowl, the lighter the wing. If the surface of the obechi is shiny, you are not finished. Transfer tape, used to stick the sheeting, weighs 1/4 oz/sq ft. Epoxy should weigh 1/ 3 oz/sq ft. Transfer tape for a Saber wing weighs in at 3.6 oz. Epoxy should come in at 5 oz. So, try not to use all the 3.5 oz of epoxy you mixed for this one wing panel. However, if you do, don't jump out the window. Your Saber won't even notice the extra 2 ounces. After the epoxy is applied, carefully put the bottom sheeting in place on the core. Cover the lower cradle with wax paper and place the wing in it. Repeat the procedure on the upper sheeting. Place wax paper on the upper sheeting and seat the upper cradle. It is really not necessary to use the upper cradle. All it does is protect any protruding obechi sheet from getting crushed to the front of the wing core. Put the cradle stack in place. Lay the paper towel on top and down into the vacuum hose area. Trim a piece of quality 2-3 mil plastic sheet somewhat larger than the assembly. Put a 1 - 2 fold down the entire length of the plastic. This will allow the plastic enough material to suck down around the sides of the assembly. Smooth the plastic down onto the sealant all around. It will be necessary to put a strip of sealant into the ends of the fold in the plastic to seal it. Pay particular attention to the seal around the vacuum hose. Start the vacuum pump and watch and listen for air leaks. Press down suspicious areas and watch the vacuum gage. It will tell you when you have found a leak. Set the vacuum pump to 5 to 6 inches-of-mercury vacuum. It is important to monitor the pressure at intervals for as long as possible. A loss of pressure is extremely unfortunate until the epoxy cures. The vacuum should be continued over night, or for 12 hours or so, depending on the epoxy cure time. It sounds kinda complicated said Yeti. Not really. said the Professor. Once you have done one panel, you find it is no more complex than using transfer tape, or spray adhesive. When I did my first bagging, I started with the stabs. The procedure is identical and being physically small, they are easier to handle and a good way to start. The Old Professor glanced over at the bust of Robert Dodgson, in the corner. He thought he detected a kind of so what? Look on the statue's face, but at least there didn't seem to be any more cracks in the statue. Remind me to dust old Bbbbob. He looks like he wants to sneeze. Well, it's bed time, Yeti. Don't forget, we leave for Canada and the NWSS contest at Mission B.C. next week. Yeti jumped up. Oh boy! We can look for Mom and Pop up in the bush. They like to spend the Summer over the border. There are more tourists to frighten that time of year. Then he sat down and a little tear rolled down his hairy face. I want to see Mom and Pop again, but I'd sure hate to leave you, Daddy. Yeti sometimes called the Old Professor Daddy. All the rest of the kids in Nursery School had Dads and Yeti didn't want to seem different. The fact that he was a head taller and was developing a hairy fuselage went unnoticed, thank goodness. Well, off you go to bed, it's school tomorrow said the Old Professor, as he snapped off the wire recorder for the night. HOWZAT! ________________________________________________________________________________
Airsharkophobia
by Scott Shaw
Bob, I'm asking for your help in fighting a new phobia sweeping the country. For lack of a professional definition I'll have to call this fear Airsharkophobia. I became aware of this condition at a recent contest where some of its victims tried to pull out my teeth. I believe that perhaps this dementia is viral in origin, and the virus was given the opportunity to grow at the 1991 NATS, possibly during some of the long intervals between flights. And now sadly I see that respected columnist Byron Blakeslee has been struck down by the affliction. The basic symptom of this disease is the fear that a sailplane will come screaming out of the sky and graze the top of ones head, or other body parts, with it's wicked shark's teeth. The unfortunate victims of this affliction are blind to the following realities:
1. The chances of getting grazed, as when the plane just comes in an inch too low, are minuscule when compared to the chance that the plane will be four inches lower and drill its moderately sharp nose into your temple, or into the base of your skull. And even if a toothless belly of the plane does manage to graze your scalp there's that pleasant little tow hook to contend with.
2. The chances of being struck by a sailplane are greatest during landing, when all the planes are converging rapidly on the same circle. At least that's the only time I've been struck or seen others struck. Usually this occurs right after the plane has made a mad dash from a dying upwind thermal. In this situation something to make the plane stop once it's on the ground seems to be an obvious safety benefit. not a danger. 3. Besides the safety argument to justify their fears, the afflicted also claim that the arresting devices allow an unfair landing advantage. This is like saying that the kevlar fuselage offers an unfair advantage over wood because the Kevlar fuselage will withstand the dork landing technique. We must all dedicate ourselves to fighting this dreaded disease, a cure must be found before more of our brethren and sistren? are afflicted. I have selflessly established the Airsharkophobia Self-help Society, ASS. Please ask your readers to send their tax deductible contributions. Now. Bob. what was that I heard about a 25% off certificate for a published letter? Sincerely-- Scott Shaw Cass City, MI October 8. 1991
Medical Alert the next generation
May 14, 1991 Michael K. Kirk: Editor 3812 Hidden Springs Road Lexington. KY 40514
Dear Michael, Thank you for sending me a copy of the April 13, 2991 Newsletter which included Frank Foster's response to my Medical Alert bulletin. Since I have been granted a second chance by our benevolent long distance kit reviewer (he can scientifically critique any glider with the facts without ever having seen, flown or built one), I must respond. I do feel at a decided disadvantage, however, because my factual knowledge of the Saber design is tainted by my having seen, built and flown them. I address the following directly to the generous guy himself. Dear Frank, The reason that my Medical Alert article was not a factual point by point rebuttal of your comments on the Saber was because I could see no points to rebut. I am not alone (except in parts of California) in the belief that the Falcon (while a good glider design) is not the equal of the Lovesong. If you want facts, look at the Performance polars. Also look at the fact that Lovesongs won the 1990 regional Season championships all over the country. A Windsong (a 9-year-old design) won the 1990 Eastern Soaring League Championship, beating the Magic (a six-month-old design), the Falcon a three-year-old design and all of the Other ground breaking designs. Just what new feature has the Falcon got that the Saber is trying to catch up with?...let me see, could it be the Control system? No, the Windsong introduced it to the world in 1982. Is it a fully formed fiberglass fuselage? No, our Maestro, Gull and Hijacker gliders had them in 1974. Is it the foam core balsa Sheeted flying surfaces? No, our Camano was the first thermal competition kit to utilize them. That was in 1979. Is it a better thermal airfoil? Not according to the performance polars. In fact the S3021 has a higher minimum sinking speed and a lower maximum L/D than does the tripped E214 of the Lovesong. Is it the swept LE planform of the wing? No, our Maestro Megan and Maestro Caliente had the same basic swept planform in 1976. Well, what is left? The polyhedral wing tips of course! While polyhedral is hardly an earth-shattering concept, I have always regarded it as having value on trainer and intermediate-type gliders. The Falcon appeared just in time to be the last great white hope for neopolybagers who wanted to step into the light of multichannel flying but could not totally let go of the darkness. Surprisingly, the popularity of the Falcon has had much the same effect on the Lovesong in the 1990s as the wave of Hobie-Hawk-mania had on the Todi and Maestro in the 1970s. Many people, it seems, who own Windsong/Lovesongs never really learned to fly them properly. Some of them lost the faith and moved on to the latest rage ...the Falcon. After they got comfortable flying the Falcon fast (unlike the floater approach they had been using on the Lovesong) they went back and tried flying the Lovesong again. Surprise! The Lovesong was a totally new aircraft. They finally started flying the Lovesong up nearer to its potential. I know of some of these folks who are now putting their Falcons up for sale and are going back to flying the more efficient Lovesong. The questions is, if the 3-year-old Falcon design never caught up with the 9-year-old Windsong/Lovesong design, is it even in the same league with the one year old Saber design? All of the flight comparisons that I have seen, all of the people that I have spoken to who have flown both the Saber and the Falcon, and all of the computer data indicate that the Saber is the higher performer in both light lift and in L/D in the useful speed ranges. What is more, they also say that it handles as well if not better. In landing, there is no contest. While the Falcon is landing on its flaps at 30 - 40 mph (they stick down below the fuselage and yet are too short to properly slow it down) the Saber slows down and lands on the spot. I have never tried to argue polyhedral vs straight winged performance in all of my 20 years of designing straight winged multichannel glider kits. Eventually the hype dies down and performance rules the day. It always has and I trust that it will again. One thing that amused and confused me about your Saber Revisited article is that you refer to the ...crescent or Schuemann plan, as found on the Falcon 880 and you imply that the Saber does not have this. But then how could you know? You have never seen a Saber! In fact, it could easily be argued that the Saber's wing planform is truer to the Schuemann planform than is the basically straight tapered planform of the Falcon. Also, the true Schuemann planform does not have the tips up polyhedral compromise used on the Falcon. Evidently Frank, you were as confused by your own article as everyone else was. What would you say if I were to tell you the rumor is that the designer of the Falcon is coming out with a new design (it is now out --the Thermal Eagle) in the 121 wingspan size range of the Saber, using an airfoil with nearly the same performance range (but lacking in the light lift end) as that of the Saber and utilizing obechi sheeting --just like the Saber pioneered. Whom would you say is trying to play catch up? Oh, I don't know. Let me see, could it be ...?
I must apologize for not giving a more serious response to your original kit review in my Medical Alert article but your astounding thesis and long-distance, sight-unseen performance analysis was really difficult to take seriously. Anyway, thank you for being the generous guy and giving me a second chance. If you ever get beyond the purgatory class gliders, give me a call. Have I got a deal for you on a new Saber! Sincerely, Bob Dodgson
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