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  • 2016 NFFS Sympo - Call For Articles
    Call for Articles for the 2016 National Free Flight Society Symposium.
    Every year  Free Flight modellers  receive an invitation to participate in the writing of that year’s Sympo.  Their response has been excellent, and this high degree of cooperation has continued through the nearly five decades of existence of the Sympo.  Free Flighters realize the importance of this volume, a volume that continues to define progress in the corner of aeromodelling that we have made our own.
    Our time is a most exciting one, in positive and negative senses. Great technical developments abound, many new and superlative materials have been introduced, the flow of information has never been easier,  yet youth participation is low and the  confrontation with law and regulatory committees makes our flying more difficult every day.
    We would like to reflect this mixed reality in the areas of interest and topics for articles that we suggest below. Throughout its history the Sympo  has been a unique tribune for technically minded authors, as it can offer more space, and a larger audience than any other alternative outlet. We encourage  contributions in this area.
    Areas of interest 
    1) Technical articles
    Electronics,
    Lost models, flight logging, energy or altitude limiters, timers, thermal detection, etc
    Aerodynamics, Airfoils, Turbulators, Flight Simulation, etc
    Combining theory and flight testing
    2)    Electric Power
    Everything, from the ground up ….
    3) Materials, Structures and Construction:
    New and Novel versus Tried and True
    4) Promoting Participation
    Social aspects:  flying alone, flying buddies, local clubs, special interest groups,         national and international organizations
    Impact of rules and regulations
    Pro Am format participation in contests
    Flying fields: fields large and small – where are existing field and how to develop new ones
    Synergy:  joint efforts with schools, national STEM programs, civic groups, etc
    5) History, book and article excerpts
    Discussing historic references of value
    6) Scale Models
    7)  Short and Long Range goals for NFFS
    As defined by the President’s Message at end of volume
    In addition to this list,  we would like to offer to interested  authors a longer list of possible subjects for articles. The list with these themes can be downloaded from the National Free Flight Society website (freeflight.org/), or Free Flight Quarterly’s website ( freeflightquarterly.com/wordpress).
    You can contact  any of the members of the 2016 Sympo Editorial Team (e-mail addresses below) for further information and support.  The preferred medium of the article is electronic, text in .doc format and separate images in .jpg or .png formats. The Editorial Team is also requesting photographs of quality to supplement the articles, this is an appeal to the many keen photographers among us.

    Louis Joyner        joyer28 at comcast dot net
    Dave Lacey          adlacey at earthlink dot net
    David Mills            davidmillsatl at gmail dot com
    Sergio Montes       jsmontes-ffq at bigpond dot com
    Chris Stoddart       chris.stoddart at gmail dot com







  • Rubber Model Trimming via PGI and TOP
    Over the course of many years Jean Wantzenriether has developed and published an approach to trimming and design modification of high performance rubber powered free flight models.  One key aspect of his method is to avoid the use of variable position surfaces except for de-thermalization. The name first given to the method was PGI, standing for Piqueur Gravite' Incidence which refers to the key aspects of thrust line relative to the center of gravity, center of gravity location and wing incidence relative to the thrust line.  Later refinements and additions to his method led to the name TOP,  for Three axis Optimal Permanent equilibrium.  TOP, like PGI, avoids variable positions surfaces. TOP additionally provides guidance effecting both the lateral axis and longitudinal axis.  


    Starting around 1980 Jean's publications on PGI and TOP have appeared in many places such as Vol Libre, The National Free Flight Society Symposiums, and Free Flight Quarterly.   "Insights on the Dynamics of Rubber Powered FAI models", a book published by Free Flight Quarterly, contains a comprehensive overview by Jean of PGI and TOP.  In this book one can find not only the PGI and TOP methods, but also other extremely interesting analyses of the design and operational aspects of a contest rubber model, in particular the role of the horizontal stabilizer and on optimum propellers.  "TOP Fundamentals" an article from this book may be read by opening the following link, TOP Fundamentals .  Additional information on the book and how to buy a copy my be found at FFQ Books .   






       

  • Ilbesheim 2011
    Ilbesheim 2011

    One of the largest turn-outs in the 2011 World Cup scene, participants from 23 nations including Mongolia, Argentina and the USA and challenging weather conditions with over 160 registered participants. A recipe for a big World Cup showdown.
    After a full month of rainy weather and possibly the worst summer weather ever recorded in western Europe, the forecast looked very promising. Sure, the weathermen had promised good weather many times before, which lasted about half a day, but this time the forecasts left no doubt. We would have summer weather throughout the Ilbesheim weekend. But just like the many previous promises, also this time we wouldn’t keep it dry. Notably the southwest of France had proven to be a serious low-pressure system generator, pushing areas of vicious thunderstorms towards the Benelux countries and Germany. And this time would be no different. Thursday night, a heavy weather system swept over Belgium, which caused the death of five youngsters at a music festival when a big tent collapsed. In fact, we could witness the weather system from a distance and although it approached us slowly, only a bit of rain touched as Thursday night.

    Bad weather moving in from the west

    Like with the previous low-pressure systems, its trailing end brought wind and turbulence and in Ilbesheim it was not different. The first round on Friday morning started therefore with a gusty wind, carrying the models towards and across a railway track. The driver of a passing train could see several modelers walking parallel to the tracks and he must have alerted the local police. At the start of round two, which was delayed due to the ever-increasing wind speeds, the police in fact arrived. Luckily they only warned the contest director, but if any one would be seen near the railway tracks again, they would press charges. This left the organizers no other choice but to relocate the starting line. And so it happened. A new location was chosen and the wind had turned as well, this time heading away from the railway track and motorway. The downwind area was not obstructed by trees, windmills or villages which otherwise made the selection of a starting positions a daunting exercise. We managed to fly the remaining 4 rounds in wind speeds of 5 m/s. Thermal activity was mild and most models landed some 1 km away from the launch. Some interesting flights could be seen. Allard van Wallene exploded a stabilizer during acceleration and Roland Koglot spoiled a launch for a sub 3 minutes flight. Nevertheless, everybody kept pushing on and by the end of the day some 11 flyers in F1A managed a clean score. At the end of the last round the sun was already close to the horizon, and Ansgar Nuttgens decided to have the fly off the next morning at sunrise.

    Robert Lesko with beautifully crafted all 'Textreme' carbon flapper.

    Saturday morning dawned with perfect conditions. A slight overcast sky and only a light drift towards the motorway. We gathered at the same position where we flew round 1 the day before. Out came the LDA ships and flappers for a performance showdown. Soon the 10 minute slot was on its way. Dirk Halbmeier and Allard towed upwind in the direction of Ilbesheim while the others decided to head for higher grounds at the south end. Soon Dirk made a perfect launch with his LDA ship. Allard followed and launched shortly after. But the pattern was off and the model shot sideways at a 45 degree angle and overbunted. A few stalls followed and the brand new LDA ship ended at some 60 meters altitude. Nevertheless, the glide was remarkably fine for a 5 min 30 flight and 4th spot. Meanwhile also Kosonoshkin had launched followed by Rene Limberger. Slowly the models where circling back to earth without any signs of lift. Kosonoshkin touched down in a winning time of 402 seconds followed by Limberger (382). Halbmeier settled for third spot (361). All flying LDA models, a sign that flappers are quickly heading for oblivion.

    History and future? Allard’s flapper and new LDA ship.

    In F1B Silz won (358) over Stefanchuk (345) and Rosonoks (342).
    Shortly after, the sunrise competition started. It was announced that the moment thermal activity could be noticed, the competition would be finished. In fact, this morning showed the best weather of the weekend. No wind, sunny and warm. Many made use of this weather to trim their models. Many flights were made, most landing close to the starting area. Although no real thermals were present, the sun did its best to warm up the air and some flights had some assistance of more than buoyant air. The rules said that the best and worst flight time would not be counted for the result. Jorg Schellhase won the event with his flapper.
    The morning of the Daedalus cup greeted us with some fine weather. But dark clouds were moving in from the south and we only managed one round before the competition was interrupted for some hours to let the rain storms pass through.

    Rene Limberger pointing to Mammatus clouds moving in

    Temperature had dropped some 10 degrees and the rest of the day it would climb back to some 25 degrees. The wind direction was again heading straight for the motorway. To be better safe than sorry, Ansgar decided to reduce the max flight time to 2 minutes for rounds 2 and 3. The wind had been dropping gradually and rounds 4 and 5 could be flown with 150 and 180 seconds respectively. Conditions were not hard, although again some LDA ships could be seen dropping fast after a perfect launch to barely make the max. Needless to say, 5 rounds combined with flights of 120 seconds would result in a huge fly off. Everybody was wondering if such a fly off could at all be organized. Participants had to organize their own timekeeper. After another move of the flight line, the poles were quickly positioned and pole positions assigned. Shortly before the start of the fly off, the timekeepers were shifted one spot to secure timing impartiality. All went like clockwork and soon the horn sounded. 29 flyers (!) towed up to find a safe spot to circle. Brian van Nest quickly moved away from the pack and launched a few minutes later. Kosonoshkin towed passed the parked cars at the other end of the line. Allard was towing his new LDA ship and made a perfect and high launch with some 3 minutes to spare. Despite some light turbulence it landed at 6:58, the strobe leds making it perfectly visible against the dark skyline. Soon the other times were known and only Koglot and Kosonoshkin came close with 6:56 and 6:50 respectively. Again, all flew LDA models but Max Herwig came close flying a regular model to a well-deserved fourth place after having lost his LDA model in a cornfield at the German nationals the week before.
    The F1B fly off soon followed against a setting sun. Without apparent helpful air, Danko Sokolic won (331) over Rigault (296) and Seifert (288).
    If there would be a price for bad luck, Kees van de Ven would have won it. When packing up for changing starting position, he locked himself out of his car with the keys inside. Things had to be organized to regain access, and some steel wire contraption was welded in the Schmal winery workshop to be able to reach a door handle through a forced gap at the window frame. Finally he managed, but the F1A fly off was already on its way and he arrived just when the 10 minute slot had finished.
    Ansgar Nuttgens and his crew organized a great event. The weather didn’t always cooperate and the nearby motorway didn’t make it easy to choose a safe starting position. Nevertheless, we had a great time. The Schmal winery in Ilbesheim proved to be a great location for camping, social events and price giving and seeking shelter for the rain. Food and drinks were served for modest prices. I’m looking forward to the video footage taken by a professional filmmaker. A DVD is to be released soon and can be ordered at http://www.creasus.de/ikarus/creasusfilm.html






  • Internet Changes In Progress - April 11, 2011
    Sergio Montes has a new email address.  You can reach him at jsmontes-ffq@bigpond.com

  • Not a member of NFFS--The National Free Flight Society?
    Don DeLoach, Editor of the U.S. National Free Flight Society's "NFFS Free Flight Digest" made the following announcement, valid for the year of 2011    

    Announcing a *Special* offer for new members: two years for half price!

    Roy Hanson has made a generous offer: He thinks so much of the NFFS and the its publication, the NFFS Free Flight Digest he is paying out of his own pocket HALF the cost of EVERY NEW member who signs up for two years.  $29 dollars gets you two years if you are 19 or older ; $9 dollars if you are younger.  Non-U.S.  members pay just $37.50 for two years. 
      
    Each Digest issue is at least 40 pages, delivered six times a year.  Each issue is crammed with Free Flight how-to, plans, contest reports, photography and much more.   The Digest covers every aspect of Free Flight: AMA, Indoor, FAI, FAC, SAM, Nostalgia--the works.

    If you are a former member who has let their membership lapse for a year or more, now is your chance to re-up for half price.   To make it easy, you can even hit the following link and use your credit card. 



  • Model Propeller Constants - Weick, Durand and Lesley
    "Aircraft Propeller Design", written by Fred E. Weick and published by McGraw Hill Book Company in 1930 makes reference to wind tunnel test results for a series of propellers with pitch to diameter ratios between 0.5 and 1.1, see pages 105 to 108 . The tests of these 13 propellers performed by W. F. Durrand and Everett Lesley are reported in "TESTS OF THIRTEEN NAVY TYPE MODEL PROPELLERS", NACA TR 237, 1926 .   You can find out more about the tests at Durand Lesley Propeller Collection and download the test report at NACA TR 237 .

    In 1994 I, Chris Stoddart, developed and posted to the internet a mathematical model based on these tests and Fred Weick's Representative Section / Blade Element theory, weick.tk.  The model made use of MiniTK a free version of the TK Solver, a mathematical modeling and problem solving software system based on a declarative, rule-based language, commercialized by Universal Technical Systems, Inc. , see TK_Solver at Wikipedia  and UTS .  The free version can still be used as a DOS application in Windows and with Linux.  You can download MiniTK from  MINITK and the Weick.tk mathematical model from Weick.TK .
    Weick.TK allows the examination of many interactions on propeller performance on parameters such as efficiency, power and thrust as effected by pitch, diameter, velocity, and rotational speed and other factors.  The program can select an optimal propeller to match a flight condition. It gives reasonable answers to queries ranging from rubber power to control line speed.

    The Rule, Variable, and Unit sheets of Weick TK appear below.

    Rule Sheet
    Status Rule
    Comment ;Program - Weick.tk, Written by Chris Stoddart, July 23, 1994


    Satisfied eta=TAN(PHI)/TAN(PHI+GAMMA)
    Satisfied C_p=QGF*B*WR*J^2*((TAN(PHI)+TAN(GAMMA))/(TAN(PHI)*SIN(PHI)))*C_L
    Satisfied C_s=J/C_p^0.2
    Satisfied C_s = V*(rho/(P*(N/(2*pi()))^2))^.2
    Satisfied eta=C_t*J/C_p
    Satisfied BETA=ATAN((4*PoverD)/(3*PI()))
    Satisfied TAN(PHI)=V/((3*D/8)*N) ;-- use without inflow
    Satisfied ALPHA=BETA-PHI
    Satisfied C_L=0.355+4.3*ALPHA-3*(ALPHA+0.075)^2 ;-- use without inflow
    Satisfied GAMMA=0.47*ALPHA+0.0073/(ALPHA+0.075) ;-- use without inflow
    Satisfied GAMMA=ATAN(1/LovrD)
    Satisfied T=(rho*C_t*N^2*D^4)/(2*pi())^2
    Satisfied P=(rho*C_p*N^3*D^5)/(2*pi())^3
    Satisfied Q=P/N
    Satisfied M_0=T/P
    Satisfied J=V/(D*N/(2*pi()))
    Satisfied PoverD = Pitch/D
    Satisfied WR = Chord/D
    * Undetermined condition IF OPT = 'yes THEN ALPHA = .8/57.3

    Variable Sheet
    Status Input Name Output Unit Comment





    File Name: weick.tk July 23, 1994

    .579 D
    m Diameter

    .722 Pitch
    m Geometric pitch


    Chord .06948 m Chord at 3/4 distance to tip

    2 B

    Number of Blades

    .12 WR

    Width ratio at 3/4 distance to tip


    PoverD 1.24697754749568
    Aerodynamic Pitch over Diameter

    8 N
    rev/s Angular velocity

    5 V
    m/s Forward velocity


    T 1.06051082397811 N Thrust


    P
    w Absorbed Power


    Q .129313391262165 N*m Absorbed Torque


    M_0 .163155511381247
    Figure of Merit [T/P in N/w]








    J 1.07944732297064
    Advance ratio V/(N*D)


    eta 81.5777556906235 % Efficiency


    C_t .120262549489696
    Thrust Coefficient


    C_p .159132947457634
    Torque Coefficient


    C_s 1.55901190738972
    Speed/Power Coefficient


    BETA .486760145073151 rad Geometric Angle of Attack


    PHI .429595614242357 rad Relative Wind Angle


    ALPHA .0571645308307935 rad Aerodynamic Angle of Attack


    C_L .548405092943241
    "Lift Coefficient" Correlation


    LovrD 12.1526639689179
    "Lift/Drag ratio" Correlation


    GAMMA .0821015133831694 rad Angle who's tangent is Drag over Lift

    1.226 rho
    kg/m^3 Air density

    .366372781256872 QGF

    Overall torque grading factor (0.366)


    OPT

    To find optimal Pitch given D,HP,N,V





    enter 'yes, otherwise leave blank

    Units Sheet
    From To Multiply By Add Offset Comment
    m in 39.37

    ft in 12

    m mm 1000

    kg g 1000

    rad/s RPM 9.549296585513721

    m/s ft/s 3.280833333333333

    w hp .001342281879194631

    rad deg 57.29577951308232

    N*m lbf*in 8.850748065226473

    lbf*in ozf*in 16

    lbf ozf 16

    w J/s


    N lbf .2248090247334889

    N/w lbf/w .224809024733

    lbf/w ozf/w 16

    rev/s rad/s 6.283185307179586

    ft/s MPH .6818181818181818

    w HP .001342281879194631

    lbf*in gf*cm 1153.16

    - % 100

    lbf gmf 454

    ozf*in gmf*cm 72.07250000000001





  • SCRAM Plans
    In issue 37 Sergio Montes and Andrew Longhurst present an article to celebrate "The 60th ANNIVERSARY OF SCRAM, Laurie Barr’s LIGHTWEIGHT CONTEST MODEL".

    SCRAM Plan



    The printed edition of issue 37 contains a full size plan on 4 pages.  As a service to our subscribers that prefer not to unstaple their printed edition or those that receive the Digital Edition the links below provide access to a a full size plan and files for printing on typical personal printers on either A4 or Letter size paper.

    Full size plan

    Tiled plan for A4 size paper

    Tiled plan for Letter size paper  

  • EIFELPOKAL 2010 - Allard van Wallene
    An active low over northern Europe colliding with warm air in the south caused massive rainfall over Holland and parts of Germany. Showers were of a clustered nature with sometimes thunder and lightning under massive towering cumulonimbus clouds. To avoid the heavy Friday afternoon traffic, I left early. In the car I played an audio book on the stereo, but my mind was with model flying, so I changed to the local radio station. They were playing a series of ‘rain’ songs: ‘Its Raining Men, Its Raining Again’ and more. Come to think of it, there are plenty of rain songs! At the German border, the station got too weak for proper reception, but the weather continued the sentiment, with massive downpour.  Visibility dropped to dangerous levels and luckily some cars used their fog lights for me to keep track. Upon arrival at the field, the F1B and C contest was well on its way. There were grey skies all around and a slight drizzle.

    Line up of shelters on F1B day
     
    A heavy shower had just moved out and it had struck lighting right in the middle of the field. The cars were shaking on their wheels! The organizers were very flexible all through the event by halting a round whenever deemed necessary. Nevertheless, some flyers were caught downwind by the rain. Later that day, the wind shifted from NW to N, straight over a downhill slope. Only a good climb and good air could secure a safe passage and a max which was set at 150 seconds. The fly off was scheduled for 6.30 the next morning. Bernd Silz once again managed the best time and Seydel topped F1C.


    Aringer with flapper

    That night we enjoyed dinner at an Argentinean restaurant, which I visited some years ago with Anselmo Zeri. A good choice of quality beef and discussions about F1A technology made us forget the weather outside.
    Next morning dawned with moderate wind and partly overcast skies, which lasted for two rounds. Like the previous years, right at the start of round one, small patches of lift were available. The big question was if they would carry the model high enough to clear the dropping slope at the south end of the field. The wind was still well within comfortable limits and I decided to take my Ex Span for a safe max. The model climbed away gently and although the slope pulled the model lower, it maxed at some 70 meters altitude. Also in round two, the wind kept a low profile, and some sunny spells made us even forget the wet of the day before. After a few minutes a large thermal passed through. I prepared for launch while others were already launching their ships. After my launch I looked up and saw something dangling from my stabilizer. Darned, towline over the stab I thought. But the towline was on the ground still in one piece. I looked up again and saw the entire top cover had stripped off the stabilizer! The model tried to stay in the thermal, but the drag proved to be too much and it slowly descended. I watched the flight in awe, before winding up my towline. I slowly strolled downwind to collect the model. Tough break, I thought. In round three Siggi Limberger walked up to me. “What a great flight that was”, he said. I was puzzled. I explained what had happened to my model, and he replied he and the timekeeper had seen my towline over the stab, which then dropped away for the model to max at great altitude. I had no clue what had happened or which model they followed, but 180 was on the scoreboard! Undeserved for sure, but I never argue with timekeepers!

    Seydel programs his winning model using Sidus electronics.

    The weather forecast was all over the place but the promised improvement of the previous day was over optimistic. Soon massive towering cumulonimbus clouds were approaching from the horizon in round three, the kind jetliners would take a detour for. One of such clouds managed to hit us during lunch break and part of the 4th round. The organizers managed quite well in halting the round and continuing after the rain had passed, in particular with the previous day’s lightning strike still fresh in memory. Although the average wind speed was around 6 m/s and less than last year’s, the turbulence levels were particularly high. Picking your own air proved to be the best way for a secure max as thermals were often small and passed at high speed. The harsh conditions made towing a real challenge. Putting up a fight for 20 minutes and maxing at great altitude made the experience the more rewarding. In round 5 the thin spectra towline was wrapped around one of my left hand fingers. The fierce turbulence required full control over the towline all the time, so my finger obviously didn’t cooperate! My model towed-in and after the adrenalin faded away, the cut in my finger made me realize I should use a left hand glove as well. After the 7 rounds only 3 managed a clean score, Uwe Rusch, Ivo Kreetz and yours truly. The fly off was delayed to make sure the threatening clouds stayed clear from the field. After another shower passed through, weather conditions were perfect: about 4 m/s wind and sunny. But with wind from the north, such conditions can be very tricky. While towing, all three of us felt a nice thermal. I launched first, but the towline slipped from my hand and the model pulled out of the bunt not in the position I wanted it to. Then Ivo launched, the model pitching up too much. The bunt redirected the model back to a near horizontal position and a stall followed. None of our models climbed away and again the Zulpich air had fooled us. Uwe Rusch launched shortly after, and although he managed to beat our times, also his flight was not supported by any clear thermal activity. I ended third only 2 seconds behind Ivo. Our models could be retrieved from a close distance with all flights being between 3 and 4 minutes.
    It seems like a chain of warm weather has been replaced by the type of weather we were used to in the eighties and nineties. Thanks to today’s carbon composite structures, many coped pretty well with the weather. We all feared we would need our rain gear for the years to come, the seven fat years now being followed by seven lean years.  Future will tell if this holds true.


    First two rounds were blessed with decent weather



    Starting line close to camp site, and wind of course.....




    F1A winners



  • Website Rewritten
    The Free Flight Quarterly website has been completely rewritten using WordPress.  This was done to make the website both easier to use and to maintain.  It is anticipated that further changes will be made in the future.

    The website can be reached at http://freeflightquarterly.com/wordpress/ or at the old address of http://www.freeflightquarterly.com where you will be automatically redirected to the new web site.  

  • Swedish and Nordic Cup 2010 - Allard van Wallene
    Just when a major heat wave was sweeping the western parts of Europe, the weekend for the Swedish World Cup was rapidly approaching. Temperature forecast for the Friday in Holland was 36 degrees, in Sweden some 10 degrees less. Ivo and I decided to leave early. And leaving from Ivo’s place at 6 AM meant I had to leave at 5. Good thing I'm an early riser! Weather was excellent all the way up to Rinkaby, the venue of both competitions. But first we headed off straight to the Ahus pizzeria to watch Holland play the quarter finals soccer world champs against Brazil. We arrived just in time, some 10 minutes late after Brazil scored the first goal. The restaurant was packed with dutch flyers, I guess the locals never knew why a group of Dutch fans would drive all the way up to their pizzeria to watch the game! Soon the spirits rose after Holland started scoring. Great fun, and the quality of the pizzas added to the spirits. The fatigue of traveling vanished into thin air, and we would have plenty of that stuff the coming days!

    We recharged our energy levels enough to check in our stuff in the barracks and do some flying. Upon arrival at the west side of the field, the fly off of the Swedish nationals was on its way. We tested some of our models. Thomas Weimer, who flew the small classes earlier that day, warned us for the tricky thermals. It later proved to be the understatement of the year.





    Antoon (r) congratulating Jari with Swedish Cup victory (Schwendemann photo)


    The next day dawned with blue skies and some 3 m/s wind, identical conditions as the day before. Thermals were present but could collapse in no time. To be honest, we never experienced anything like it. Even ace flyers like Findahl, Hellgren, Persson and Holbom had difficulties finding good air and keeping the model in thermals. Sub maxes started to appear on the scoreboard at a rapid pace.





    Must by fly off time!


    Remarkable to see that some designs could handle the tricky thermals pretty well by keeping a tight turn, while other models just wondered about out of the good air. If there were any conditions to check wing warping and centering ability, this was the ultimate trial. Despite the tricky conditions, some managed to max out using utter concentration. Since the fly off was scheduled at 7.30pm, there was some time for lunch and rest. The first fly off round saw some good thermal activity, but only Antoon van Eldik and Jari Valo managed a solid max. F1B saw similar conditions with only Rosonoks en Stendal maxing. In F1C nobody had maxed out and Juri Roots showed the best climbs all day to secure a first spot, but with Pieter de Boer only 7 seconds behind. F1Q showed the first results of the rather liberal model specifications. Matti Lihtamo had worked hard over the past year to come up with a box full of extremely hot models. With a 1 kw motor it outclimbed even the best F1C model. When launched it accelerated so fast it was hard to catch it by camera. Ten seconds motor run would have been more than sufficient as the last 5 seconds of the 15 second motor run, the model got out of its climb pattern and needed about half the attained height to recover due to its low stability margin, still more than enough to beat Andreas Lindner. The second fly off in F1A saw different conditions. Thermal activity had died out almost completely. Jari decided to make a dash to the north east corner of the field where he could benefit from unobstructed upwind area and therefore turbulence free air. He towed patiently for good air. A great launch followed with a rock steady glide to beat Antoon with more than 2 minutes difference. F1B had a similar show down. Remarkable to see the flyers could bring and use their own timekeepers, which led to some commotion among the two contenders with a model being ‘followed’ which had already landed. The many binoculars pointing in the right direction sorted that out quickly and Hagen Stendal topped Rosonoks by (at least) 10 seconds. A rotation of timekeepers could have easily avoided this unrest.





    Antoon in utmost concentration programming his ship.


    After this thrilling fly off, we retired to the barracks to eat some of our noodle fast dinners, which tasted remarkably well. Right after we finished the prize giving was on its way with the traditional cookies, soft drinks and (cool!) beers. The prizes were beautifully crafted blue glass sailing boats. That night, Germany was playing against Argentina and by the cheering noises through the barracks one could keep track of the scores.


    The next day the movement of the trees announced a bit more wind compared to the day before, but the clear blue skies and wind direction were signs of another tricky day for this year’s Nordic Cup. And tricky it was: Kosonoshkin, Assmuss and Valo managed to make only one single max, Anders Persson (2008 winner) no max at all. Your’s truly was thrown out of good air in the very first round after having launched high in what appeared to be good lift. Antoon van Eldik was like the days before, going strong for another clean score, but bad air spoiled his chances in the very last flight: 52 seconds.





    Nordic Cup winner Ivo Kreetz (L) and Mike Holmbom


    The downdrafts were particularly vicious. The one-liner of this weekend came from Michail Kosonoshkin: “Hey Antoon, I make only one max today, but I still beat you!” This summarized the tricky conditions. Ivo Kreetz, who damaged his Baldrick on a row of rocks the day before, had to switch to his old but reliable ‘service canon’, a short stubby model with low cambered thick airfoil. This model could handle the conditions particularly well, by sticking to the thermal like no other model. All flights were very high and one could see his confidence growing by the round. After the last round, only two maxed out, Ivo and Petri Kuikka. The F1B models could apparently handle the condition lots better with 9 (!!) flyers maxing out, almost half of the competitors attending. Also in F1C 3 out of 4 maxed out and it was again Roots beating Pieter. In F1Q it was once again Matti Lihtamo, but this time his opponent was Ron Assmuss who did somewhat better compared to his F1A flights. The rest, food, rest and fly off schedule was identical to the day before, although the wind was some 1 m/s stronger. Shortly before the fly off we learned that Anselmo Zeri had passed away. This gave Ivo and me a big dent in our spirits, but decided that Anselmo wouldn’t have it any other way than winning this event. The F1A fly off was soon on its way. The starting position was close to the south east tree line which marked the very edge of the field. Kuika moved away from Ivo and was battling the turbulence, circling his model dangerously close to the ground at times. Thermals were absent, and Ivo made a good launch to some 75 meters, a couple of meters more than Petri. This extra altitude made the 16 seconds difference for Ivo to win. Ivo’s flight of 220 seconds traveled almost the full length of the field. Quick math yielded a 6 m/s wind speed.


    At the prize giving we had one minute of silence in memory of Anselmo Zeri who was a frequent visitor at the Swedish and Nordic cup. The prizes of this event were not the common trophies, but traditionally crafted ceramic dishes made by the wife of Tom Oxager.


    This year’s events were blessed with fine weather but the trickiest thermal conditions ever seen. Many were getting desperate and started doubting either their flying skills, model quality or both. Judging the flight times on the result lists it was better to keep the trim of the models untouched, erase the downdrafts from memory and reboot the flying skills for the next competition. The memories of Anselmo however, will for ever stay with us…..





    Beautifully colored glider




      
    Jari with Tchop flapper, he didn't use it in competition.




    Lihtamo's hottest F1Q in existence with 1kw motor. Catching this rocket on picture was more luck than anything.

    [Original Posting by Allard van Wallene, July 11, 2010 - re-entered by Chris Stoddart July 12, 2010]