11-Dec-18 - 03:58 PM

Thermal Circle Text - Thermal Circle 11

Written by Hayden Daley - 14 September, 2007.
Welcome to this edition of the Soaring Circle in this edition we will be having a detailed look at the Lomcovak Logger as mentioned in previous columns and the second Soaring Circle interview with one of Australias best F3b flyers Gregg Voak.

I must take this opportunity to congratulate David Hobby on his second F3j world championship victory, he has one this event twice in a row, which has never occurred in the history of the F3j world championships. I feel this has proven that Australia’s top pilots are equal to or better than any one in the world. This result is supurb, and should encourage other Australian glider pilots to aspire to achieve the same result.

Lomcovak Logger

Firstly I would like to thank Mike Oreilly for allowing me to borrow one of these loggers for review. The lomcovak logger is a miniature pressure sensitive height logger. The unit works by plotting your flights as a line graph on a computer. These plots allow you to firstly compare launch heights and secondly run analysis of your flights, for example if you check your stopwatch at a certain time you can check whether you were climbing or descending at this time, this is an excellent way to practice and to help hone your thermal skills.

The logger has the following dimensions, length 38mm,height 13 mm and a width of 18mm. With this small size the logger should fit in most models. The weight of the unit is 9 grams with a JR cable. It requires a power supply between 4.4 and 9.6 volts. The current consumption is 15 mah and it has resolution of 0.5 meters. The logger needs software that can be downloaded from the internet, their was no problems downloading this software. Different sampling rates can be chosen using the DIP switches on the logger,these are small switches located on the logger. The total memory capacity 8 180 records in the standard version and 32 720 records in BF version. The logger uses a precise atmospheric air sensor so it needs surrounding air pressure to operate when installed in a model, in a sealed environment the unit will not be accurate. As the logger is actually an air pressure logger you should place the unit where pressure effects are minimal otherwise inaccurate plots can occur. The instructions for the unit are very specific this may occur.

Due to deadline restrictions I flight tested this unit in a power model. When testing I simulated launches, circling while climbing and descending at different rates and long approaches to simulate returning from downwind after finding a thermal. During these tests I used a stopwatch to run comparisons of the “plots” that were made during the tests. During testing the logger worked as required, It plotted the flights as they occurred and comparisons of these flights showed good accuracy in this logger.

Overall this product worked well, showed good accuracy and comes with the promise of good accurate plots of your flying. If you wish to analyse your flights this logger will solve the problem. If you wish to acquire one of these units please contact Mike O’reilly at Model Flight.

Gregg Voak Interview

You have been the most successful Australian F3B pilot over the last couple of years, you are very difficult to beat in competition. As a bit of history, how long have you flown radio control models?

Thank you for those kind words. I have been flying RC since I was 13 so that makes it 24 years. My first model was a Pilot Cessna 180 with an OS 15 which flew on 2 channel radio, just motor and rudder. I remember that the radio was a Micro brand and I think it cost about $100 which I paid off doing chores. It seemed like a fortune back in 1981!

How long have you flown F3B competitively?

I started flying F3B in 1996. Back then I was very competitive in F5B electric gliders. I had just competed at the World Champs in the Czech Republic and on the way home I called at a hobby shop in Amsterdam called Jet Speed Models. This was the home of the ‘Fletcher’ F3B glider designed by Fritz Donker Dyvis. Upon returning to Perth I wasted no time in getting it flying. I nearly trashed it the first flight because back then I flew with the WA Radio Soarers and we only had a bungee in service that day. Well it was blowing about 20 knots, I stretched it back and I let it go. The model went up but the bungee kept on stretching and the model went back over our heads and nearly hit a huge Pine tree behind us. After that we resurrected an old rules winch, the ones with the unrestricted M50 and with 1.5mm line launching into the Fremantle Doctor it really blasted! It is a credit to the model that the wings never blew off.

That same year I headed to Victoria for their State F3B titles. This was my first F3B competition. I think I placed 1st or 2nd in this competition. This was mainly due to my fast speed times. Flying F5B really helped me in this task. The other reason I did so well was due to the help of the local pilots like Rod Watkins, Mark Doyle, Mark Withers, Graham Johnson and Tim Mellor. I was really grateful for their help and advice. After this comp I was hooked on F3B.

I have seen you fly electric helicopters at the V.A.R.M.S field, what other types of models do you fly? Does this other flying improve your F3B flying skills?

I am never far from electric models. As you point out I have been flying helicopters lately. I find the challenge of these models really keeps me motivated towards flying. I also fly ducted fans jets, pylon racers and scale, all electric. As well as these I fly large scale gliders including some very powerful tugs. These big models have a different energy about them and they are a real joy to fly. Basically I will give anything a go, I believe it helps with my competition flying. It’s all stick time!

You have won a lot of competitions over the years, which competition victories have provided the most satisfaction?

Well I would say the LSF Thermal win at Jerilderie in 2001 was very satisfying. Mainly because in Australia it is the number one gliding event. After 12 rounds Carl Strautins and I were equal first and I won on a count back on the dropped scores. Jerilderie, I would say is easily one of the toughest thermal competitions in the world due to the conditions, amount of competitors and rounds flown, and close results.

But for me the most satisfying competition was the 1999 F3B WC’s held at Crudim in the Czech Republic. Whilst I ended up in 13th position, l lead the first 3 rounds. It was such a buzz seeing my name at the top of the leader board. I think it was this comp that it I realised that we Australians have equal to or better thermal skill as anyone else in the world. It was a time to stop copying everyone and trust in our own skills. I think this why Australians are gaining respect at International competitions.

You have gained a place in the next Australian F3B world championship team. Do you think you can emulate David Hobby and win the event, or gain a place in the top ten?

Well I sure would like to have the same result as David. I think his win is fantastic and well deserved, I know he put in a lot of practice. This year we have a strong team. David is coming along as Team Manager and I have my friend Jens Buchert calling for me. The model I am flying is very competitive, in fact it has won the last three Euro Tour events. So I guess there are no excuses, I’m backing myself for a top ten finish, but more importantly I think the Aussie Team will be on the podium!

What transmitter will you be using at the world championships?

I will be using the Multiplex Profi 4000. I have been using this radio for some time now and I find it to be very reliable. It provides me with all the mixing functions required to get the most out of current F3B glider designs. I have also used the Graupner MC24 that is also OK but I personally think the Profi 4000 has the edge.

What servos will be in your competition models for the world championships?

Well here I go for the tried and tested DS368’s or the DS361’s as they are now known. These are JR’s 13mm thick digital metal geared mini servo’s. They have proved reliable and as long as you don’t do anything dumb, like land with the flaps down (learnt by experience) then they will hold up well in competition.

Can you recommend other wing servos suitable and strong enough for F3B competition flying?

Multiplex have a new small digital servo coming out called the Polo which looks like a digital version of Hitech’s HS85 metal geared servo. There is also the Hitech 5125 which is a very thin 10mm thick digital servo. I think the common parameters for servo’s in F3B are (a) digital, because of their holding power and (b) metal gears. As long as they are reliable then they must be good. The only down side to the metal gears is once they get old they start to slop. This can usually be fixed with a new gear set.

What receiver will you be using in the event?

I will use the new Multiplex 7 channel RX-7-Synth DS IPD. This Rx is 56 x 23 x 24mm in size so it fits easily into the current gliders. It is dual conversion with IPD meaning it is FM not PCM. The benefit of these new generation Rx’s is that they are synthesised so you don’t need crystals to select the channel. In addition to this they have a glitch counter that tells you if you have a problem with signal. If you hook them up to a laptop with the optional PC interface lead then you can determine if the problem with signal is from interference, low battery under load or low signal. This is especially useful in setting up your antenna as ‘tuning’ your layout will ensure perfect and reliable signal in all conditions. There is nothing worse for me than having a model glitch when you least expect it. It ultimately ruins your chances of flying and finishing well.

What type of receiver batteries will be in your world championship models? How many cells, what type and what capacity will be in the model?

I normally use a 5 cell configuration but it depends on the model and what will fit. I use NiMh cells of good quality and cycle them before an event to ensure they are performing OK. I usually trash cells that are more than 2-3 years old.

Which type of charger will you use to charge your world championship models?

I use the Schulz Chameleon charger. This is pretty much overkill for gliders but as I fly electric models as well I have a top end charger. I would say that any charger that has the ability to give you charge and discharge with some sort of display to let you know what it has put in and taken out is the minimum requirement. If you don’t know what’s going on with your batteries you can be asking for trouble.

Which winch line do you use when you compete, what brand? what poundage? and what diameter?

I have for a long time used Opac line, which in Australia is sold by Gerry Carter or Bill Bland. This is excellent line with good energy return and stretch. I normally use 1.2mm for everything up to about 20kmh wind then I change to the 1.3mm. I’m not sure about the poundage rating but it must be about 175 – 200lb. When we fly at a World Champs we have used the 1.1mm a lot. This was due to the light conditions and that we had 2 or 3 guys looking after the winches. Having helpers makes a huge difference! The Opac line is expensive but you get what you pay for.

Which F3B sailplane will you be using as your main competition model at this event?

I am using the new Caracho 3000 from Vector Model Technik of Germany supplied through Model Flight. These are carbon skinned, fully moulded F3B models. They are available with one or three piece wings. I initially planed to take one-piece wing models to the Worlds as these are generally lighter but we as a team could not get an airline to guarantee that we could take such a long box without excess charges I changed to the conventional three piece design.

You are allowed backup models at the world championships, which backup models will yours be?

For me I think the best thing is to have all the models the same. This maybe a little different to say the F3J pilots because they can change their model to suit the conditions after every flight. With F3B you must fly the same model for all three tasks before you can change. I feal it is better to have one model type and learn to fly it in all conditions.

There are many F3B competition sailplane designs for sale, can you please tell Radio Control Model News readers in your opinion, what the best F3B models are at the moment?

The single best thing I like about gliding is that anyone can buy (given their budget) the best models in the world, the same ones that are used by World Champions, for me it makes the playing field very even. In saying this there are many excellent models available. The Estrella from Heiner Fischer is a model that I flew for several years and is still a very good F3B/thermal glider. I understand they have a new wing coming for this model which promises more speed. The new Caracho 3000 that I am flying is an excellent model with easy handling. The models from Jaro Muller have been very good thermal models but unfortunately nothing has stood out for F3B. Two other models are the X21 and the Viking from VV models, both show good potential as well as the Furio. One thing to consider when choosing a model is the question of local support in case you have a problem. Dealing with overseas manufacturers can be very difficult at times.

Wing sections are critical for performance in competition sailplanes, what are the best flying wing sections for F3B at the current time?

It may surprise readers to learn that I don’t pay a lot of attention to the airfoil selection. In saying that we are limited of choice to what the manufactures are using on their models anyway. If we were to manufacture our own moulds than of course the question of profile selection plays into it. It seems the current selection of F3B models on the market are orientated toward thinner, low chamber profiles optimised for speed. This would be the sections I would choose.

Good winches are critical for good competitive launches. Have you constructed a special winch for the world championships? If you have are you prepared to share the specifications with our readers?

Well I have personally built three winches of my own but they were all quite standard. Up until recently I have been using a winch made for me by David Morgan, he is a master when it comes to putting these together and it was very smooth and powerful. I have just recently changed over to the Hollenbeck winch that comes from Germany. These are the most popular winch in Europe and for good reason, smooth and powerful. Current rules limit which power by total resistance so there is little you can do to a winch. Make sure you have a good battery and keep your connections short with good low resistance connectors. The most important issue is to make sure when using packers to change the drum diameter is that they are VERY secure. I have seen accidents resulting in injury, so please treat these winches with respect.

Is it difficult dealing with the pressure during these major competitions?

I definitely used to feal the pressure during a competition. In the last couple of years I have been very interested in coming up with some very simple philosophies and preparations that help me avoid these pressures. 1. You must ensure that all your equipment is sorted, this includes your models. Test flying a new model in round 1 is just putting pressure on yourself. 2. Make sure everyone on your team understands their respective job during a task. Having two or more people giving conflicting information is going to have a very negative effect on your flight. 3. Don’t try and do everything yourself. When launching I just have the Tx. I will have someone else throw the model and drive the winch. If something is wrong with the line or winch they will take care of it. My job is to concentrate on the launch. Good launch height helps to take the pressure off. 4. If you have a bad flight you have to put it behind you. This is easier said than done. Nothing you do will get those points back. If you let it effect you then you will not be in the correct frame of mind for the next flight. If you go around smiling at everyone it puts the pressure back on them! 5. Practice. Being familiar with your model in different situation/conditions is a huge help. Sometimes we have to downwind launch, how many people practice this? If you do it well you will put pressure on everyone else. 6. Have a plan before you launch. Take some time to study the weather before you launch, try and figure out where the thermal will be before you get there. Following other people around the sky is not the solution. Trust in your own and teams abilities.

There are many more small details that you can do before and during a competition, take time to sort these out before you fly and you will see improvement in your score and ultimately you will have more fun. Remember to “win buy not loosing.”

Will you be practicing more than usual for the world championships? How many times per week will you practice?

I would like to say that I practice a couple of times a week before a World Champs but my current job has me away from home a lot. If I get to fly every second weekend at the moment I will be lucky. For me, having the experience really pays off when needed, but having a few days flying just before the WC’s allows me to completely focus. It’s a far from ideal regime but its what I have available.

F3B has three disciplines, thermal, distance and speed, which of the three disciplines are you best at flying? Which discipline do you on average score highest?

Speed is the task I prefer followed by distance. I have a lot of experience flying speed from the F5B days and it has helped my in F3B. Speed is also one task where you can put a lot of points between yourself and the competition because you are flying individually but the result is group scored. Distance is a task that you must take care. It is easy to loose points here as well. Thermal is usually a lot closer. I think F3B competitions are won on speed. You can make some mistakes in the other tasks but if you have good speed results your name will be at the top of the results.

Good luck at the world championships, I wish you all the best and I hope you achieve your goals at this event, and fly to the best of your ability. Thank you for this interview.

No problems. I would like to take this opportunity to thank all the modellers and retailers for their past and continued support of the Aussie F3B/F3J gliding teams. Sponsorship and monies raised from raffles ect go a long way to help teams costs when travelling overseas. I would also like to extend an invitation to modellers who may have not tried gliding in the competition form to come along and have a go. I think the Australian model gliding community is a friendly and helpful one so first timers should feel confident they will get the help they need. Thank you.



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