Teknikler

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Helikopter öğrenme teknikleri ( Bana göre )

Herkesin model helikopter veya başka bir konuda öğrenme sistemi farklı olabilir. Fakat temel olarak yavaş yavaş ve sistemli olmalısınız. Özellikle hangi seviyede olursanız olun insanların sizi izlediği bir ortamda yeni hareketler denemeyin. Birçok kişi size acaba ne zaman düşecek diye bakıyor olabilir. Sizde başkalarının uçuşunu seyredip " Bunları bende yapmalıyım " fikrine sakın kapılmayın. Yoksa sonuç CRASH! Onun için hobinize zaman ayırıp sistemli çalışmayı seçin. Model helikopteri hakkıyla uçurmayı öğrenmenin çok uzun bir zaman alacağını aklınızdan çıkarmayın. Hazırlıklı olun muhakkak modelinizi bir gün düşüreceksiniz. Fakat bunların sayısı sizin elinizde.

Öncelikle size iyi bir bilgisayarınız için uçuş simulatörü öneririm. Eğer önceden model uçak uçurduysanız dahi helikopter simulatörünün faydası muhakkak olacaktır. Uçaktan helikoptere geçmek sanıldığı kadar kolay değildir. Uçaktan edinilen bazı refleksler helikopterde zararlı olabilir. Simülatörünüzü seçerken mevcut kumandanız ile kullanılabilmesine özellikle dikkat edin. Model helikopterinizin yapımını tamamladık dan sonra önünüzde iki seçenek var.

Birincisi : Bir ücret karşılığı hocanızın helikopteri ile belli sayıda ( ki bu en az 20 ) uçuş yapıp yolunuza devam etmek.

İkincisi : Bir uçuş kulübüne gidip orada uçuşunu beğendiğiniz ve güvenebileceğiniz birinin yardımına başvurmaktır. Herkesin uçuş stili ve öğretme konusundaki sistemi farklı olduğundan, bir kişi ile başlandığında sonuna kadar aynı kişi ile çalışmanızı öneririm. Eğer her önüne gelen bir şey söyler ve setupınızla oynarsa asla tam uçmayı öğrenemezsiniz.

Genel : Sistem olarak helikopterde önemli olan öğeler açılar , yükseklik ve hız. Bunları kontrol altına alabildiğiniz zaman uçmayı başardınız demektir. Ayrıca uçuş pistinin çok kalabalık olduğu günlerde çalışmamanızı öneririm.

Türkiye' de helikoptercilik daha emekleme aşamasındadır. Önceki yıllarda maalesef işi bilen kişiler bilgilerini kendine saklamış, bu işin ticretini yapanlar müşterisi az diye gerekli ekipmanları ithal etmemiş. Sonuç, tüm Türkiye de 10-15 helikopterci ve dünya klasmanında alınan kötü netice. Biz bunu değiştirmek amacındayız. 1997 dünya şampiyonasında gördük ki , bu iş takım işi. Bir kişinin kendi başına yapabileceği bir iş değil.

Şu anda çok bilinçli ilerleyen bir grubumuz var. Bu grupta yeni arkadaşlarımızı da görmek, bilgilerimizi onlarlada paylaşmak istiyoruz. Şu anda ülkemize birçok değişik helikopter ithal edilmektedir. Temel kural parçası en çok ve rahat bulunan helikopter en iyi helikopterdir. Bu uzun yıllarda böyle kalacağa benzer. Modelinize bir hasar geldiğinde bir parça için aylarca beklemek zorunda kalırsanız, sonunda bu işten bıkacağınız ve bu zevkli hobiden istemeyerek de olsa ayrılacaksınız. Onun için en iyisi bir helikopter satın almadan konuyu bilen birkaç kişi ile konuşup, almayı düşündüğünüz modelin yedek parça temin sorunlarının olmadığından emin olmak gerekir.

Helikopterin model uçağa göre bence iki avantajı var. İlki, uçmak için bir piste ihtiyacınız yok. Ben ilk çalışmalarımı evimin yakınında bulunan çimenlik bahçede yaptım. Oysa uçak için çok daha geniş ve açık alana ihtiyaç var. İkincisi, helikopter uçağa nazaran çok daha fazla konsantrasyon gerektiren, bir anlık dalgınlığı yada şımarıklığı affetmeyen bir alet. Aman dikkatli olun.

Helikopter Uçuş Teknikleri

Nose-In Öğrenme Teknikleri

Nose-In veya bazı Amerikalıların söylediği gibi Tail-Out ( Kuyruk dışarı ) duruş pozisyonunu öğrenmenin değişik yolları vardır. Fakat neticede bunların temelleri aynı olduğundan konuyu size genel olarak tarif etmeye çalışacağım. Burada tarif edeceğim sistemi uygulayabilmeniz için hover yapabiliyor olmanız şarttır. Ve ayrıca en azından sağdan ve solda 90°de modeli ters kumanda vermeden tutabiliyor olmanız gerekmektedir.

Nose In durumunda Throttle ve pitch. dışında her kumanda ters olacaktır. Yaw ( Rudder ) , ileri ve geri cyclic ve roll ( aileron ) ters olarak çalışmaya başlayacaktır. Helikopteri nose in konumunda sabit tutabilmek için en büyük ip ucu sağdaki stick'i helikopterin gittiği yöne kumanda etmektir. Örnek olarak heli sağa yatıyorsa stick sağa, sola yatıyorsa sola. Uzaklaşıyorsa ileri, yakınlaşıyorsa geri. Bu refleks sizin nose in için cankurtaranınız olacaktır.

En önemli noktalardan biri kumandaları karıştırmaya başladığınızı hissettiğiniz anda hemen tail in konumuna dönmenizdir. Bir diğer yöntem ki bu özellikle uçaktan helikoptere geçenler için yararlı olabilir, uçuş esnasında nose in'e dönmektir. Bu belki size daha kolay gelebilir. Helikopter size doğru gelirken gittikçe yavaşlayıp nose in hover konumuna geçebilirsiniz. Fakat ne yapacaksanız yapın ama hararetleri yavaş ve sakin yapmaya çalışın. Sakın başlangıçta bir sürü insan sizi seyrederken nose in hover denemeleri yapmayın. Eğer mümkünse bir arkadaşınıza kablo ile bağlanın.

Ben Nose-In hover yapmayı daha değişik şekilde öğrendim. Training gear takarak helikopterimi nose-in konumda yere koydum. İlk önceleri sadece aileronu kullanarak elevatore hiç dokunmadan beş altı kere 5-10cm kalkıp indim. Daha sonra aynı şeyi sadece elevatorü kullanarak denedim. Daha sonra tüm kumandaları kullanarak birkaç saniye hover yapmaya başladım. Bunu sürdürdükçe ve her seferinde yüksekliği ve hover da ki kalma zamanını arttırdıkça bir süre sonra istediğim kadar nose in hover da kalabildiğimi gördüm. Nose In esas olarak normal hover dan hiç farklı değildir. En başında nose in hover ile hover ı öğrenmiş olsaydık düz hover dada en azından şimdiki gibi zorlanacaktık. Olay kendi yarattığımız refleksleri kırmayı ve onlara yenilerini ekleyebilmektir.

Cliff Hiatt' ın ağzından Collective setup tavsiyeleri

For collective setup. I try to set up the mechanics and the servo relationship in conjunction with the pitch curve trimmers for linear collective response. In other words, I want the entire range of the collective stick motion to have the same feel with regards to control response. The way I accomplish this is as follows. Determine the maximum collective range that you desire for your particular model, skill level or flight profile. For instance, for F3C I use -6 deg. to +12 deg. for a range of 18 deg. total. Determine the "center" of this range by dividing the total range by 2 for 9 deg. and subtract this from the maximum positive setting for a "center" of +3 degrees. Likewise, for a range of -10 deg. to + 12 deg. (typical 3D) the center would be +1 degree.

Next place a servo wheel on the collective servo such that when the collective stick is in the center and the curve trimmer is at 50% for this point and the ATV's are 100%, the output hole is 90 deg. with relationship to the pushrod. (If the collective system has an intermediate push / pull bellcrank then set this up so that it is in neutral as outlined before.) Now adjust the next component of the collective mechanism (collective arm or tilting servo) so that it is in the center of it's mechanical travel or "neutral". With this done, adjust the next component, usually the swashplate (or collective mixer for fixed swashplate models) to the center of it's mechanic travel.

For the rotor head, adjust the washout mixer (for the flybar) so that the mixer arms and the flybar control arms are neutral (level) and roughly set the paddles for 0 degrees. (Fixed swashplate models: adjust the rods from the swashplate to the flybar arms etc.) Now install the blades and adjust the rods for the bell / hiller mixers so that they are neutral (level) when the blades indicate the "center" of the pitch range. Make sure the mixers are configured so that they will provide the desired pitch range. Rotate the blades to each 90 degree position around the machine and check to see if the swashplate is in neutral. (It is if there is no pitch change at the blade.) Now set the paddles so that they have 0 degrees in them.

Now for setting the pitch curves. Set the over all servo wheel size and ATV for pitch by checking to see that you realise the range that you are setting up for. If the range is too large or too small adjust the servo wheel size or ATV's. Try to keep the ATV's close to 100% to 110% for the best servo resolution and power. (For multiple flight condition radios like the 9Z, carry the ATV settings over to all flight conditions.) Use the collective curve adjustments to set each flight mode to have the desired low, mid and high points. Use the point trimmers to make each pitch curve follow a straight line between these points. For a two speed setup you will want to de-pitch the mid point for the idle up modes.

As you can see, the process starts at the servo and travels throught the system to the blades and finishes with the radio setup.

First Aerobatics

So you can Hover with complete confidence,
fly around at High Speed, do 'power on' Descents, and even a little Nose In?
What is next?

Every flight should have a purpose now. It can take years to become a proficient aircraft pilot, helicopters are no different, in fact most people will find them much more challenging for a longer period of time. Learning a new maneuver will be a rush, but perfecting it will take a lot of time and practice. A new skill will require a little modification to the heli and/or radio setup. Do not get impatient, take it easy, but as soon as you are comfortable, push yourself again.

Most Flyers will have the advantage of some local expert help, those that don't will have to make sure that both the heli and themselves are ready for the task at hand. Time spent learning nose in hovering, doing circuits both clockwise and counterclockwise, and being able to power descend from both left and right will be invaluable. Orientation and Visibility will be lost countless times during training and experience is all that will avert a crash.

But you want to throw caution to the wind and go for it. All righty then.

Oh Yes, I forgot to mention, flying is going to get a lot more fun now, So SET YOUR TIMER. Many flyers 'FIRST AUTO' is because they ran out of fuel. That is why many think Autos should be learned early.

Helibuf has a great page on autos, Check it out.

Stall Turn

The Stall Turn is probably the first 'Real' maneuver that should be learned. (Autos will be argued by some but hey, this is my page) You should be comfortable with flipping to Idle Up to maintain a good head speed. If not, go directly to Jail, do Not pass Go, and do Not collect $200.

The first stall turns should be down wind. Fly by at full or near full throttle, first time nice and high, pull back the elevator (aft cyclic) nice and slow and release when the heli is pointing Almost Vertical. (Even 45 degrees is a good starting point)

You may now wish you had paid more attention to tail rotor, gyro, and Revo setup. Its too late now so just hang on, heli will probably rotate on its own before it starts to descend and/or return, help it around with rudder but do NOT try to push it the other way, that could be a big mistake.

The Shuttle doesn't like flying backwards too much so chances are real good, before it gets too close to the ground, it will be flying back at you going nose first, albeit towards the ground. Just add the rest of your Collective, if stick isn't bent over yet, and slowly pull back the elevator until almost level and release. The head may be screaming and the heli is trying to go vertical again, cool, its still in one piece.

Do this over and over again, reducing the collective during vertical so it goes straight up and down and timing your rudder for nice slow turns at the top. Do these in both upwind and downwind directions, and turn rudder in both directions.

After a couple of tanks of fuel you will want to fine tune the revo mix.

Fine tune REVO...

If heli is trying to rotate at the top of the stall when collective stick is set for zero degrees, you will have to correct.

If Rotating Clockwise at the top of stall turn ADD a bit of tail rotor 'REVO' Pitch when Main Blades are at '0' degrees, Subtract a bit if rotating counterclockwise. These changes should only be done to the 'Idle Up Revo' settings.

Now go out and practice some more. When ready to try first 540, start applying the rudder just a little earlier. Under-rotating or over-rotating will give you a rush that will take a while to forget.

Loops

The Stall Turn was good practice for using both thumbs and getting a feel for the heli in abnormal flying positions.

Your head speed should now be well adjusted for idle up and the tail rotor revo mixing has no surprizes. The heli should be close to being able to fly hands off at fast forward flight, in idle up, without climbing, diving, or rolling. If adjustments are needed they will be small, but will make a difference. Most radios will have a stunt trim adjustment. Usually a little down (forward cyclic), left cyclic, and left tail rotor will be needed. Only 3 to 5 percent should be needed for cyclic. (trim heli with 3/4 tank of fuel - when full heli will dive a bit, empty it will zoom)

I run a slightly nose heavy ship and actually need a little UP (Aft) cyclic to trim, go figure?

Your control setup should start approaching maximim throws, using some expo (especially on fore/aft cyclic), and your normal flying only requires minimal stick movement. No more hauling the sticks around from corner to corner for normal flight.

Head speed is more critical, 1500-1600, to ensure quick response if you screw up.

NOTE*** Head Speed is more critical than lots of Pitch. No matter how much pitch you have, if the head speed decays, you will be in a lot of trouble.

Your Stall turns have taught you that it takes little Aft cyclic to get the nose pointing up and heli will carry some speed vertically for a while. At least I hope so.

Loops can be done many different ways. Your first will be surprizingly easy.

First Loop Attempt

You are flying by (Fast), about 50-60 feet up (300 if your eyesight is good), INTO the wind, (if any), and at 3/4 to full collective.

Start to pull Aft cyclic Slowly, leave everything else alone, as the heli goes past verticle continue pulling a little more Aft. Once the heli is at the top of the loop and fully inverted, you can pull the rest of the cyclic and release to normal just BEFORE the heli appears to be upright and level. Releasing to 'neutral' late will cause the heli to zoom back up and kill what little forward speed you have left. (You could then do one of your stall turns which is now down pat ??)

Your first loops will resemble the small letter e to begin with and you will have gained altitude but at reduced forward speed. The 'head' will gain a fair amount of speed during the down leg (pulling positive pitch while inverted).

Just keep practicing to get the feel of the loop. After a while you can start varying the collective settings, on entry, at the top, and on the down leg of the loop to get them nice and round. By varying the Collective and Aft cyclic you will learn what is most effective and desirable.

By lowering the collective pitch a bit as you go over the top and then decreasing pitch even more during the downward leg, the loop will be much rounder and exit height will be much closer to entry height with much more forward speed built back up. Just remember to readd collective at the very bottom of the loop.

Your two thumbs will be going in different directions at times so think it through BEFORE you do it.

After a short time you could try a variation of the loop, a traveling forward tumble. Actually real easy. At a moderate forward speed just pull full 'aft' cyclic, followed almost immediately with full 'negative' collective, once the tail has rotated past the forward position just reapply full 'positive' collective and release 'aft' cyclic when heli is flying forward normally again. Its over before you have time to panic.

Now burn another gallon or two of fuel and ROLLS will be next.

Rolls.....

If you are still a little shakey doing loops and stall turns, GOOD. If this was 'easy' more people would be flying Helicopters.

Rolls are probably the most intimidating of the basic manouvers. Questions about roll rate, revo settings, and sustaining head speed at negative pitch settings SHOULD be on your mind. If you have come 'this far' it is time to just GO FOR IT.

Your basic setup should now be pretty close to ideal for the 'Idle Up 1' mode. Fine tuning will NEVER end, and finding a new twist on setup is the name of the game.

When doing your first roll, the Key is keeping FORWARD speed up. Keeping head speed high when going to negative pitch has been taken care of with your setup by now.

Unlike an Airplane, you do not have the luxury of having a constant source of power pulling you forward. The Heli depends on INITIAL forward speed to complete a roll. So we CHEAT a little bit. Just go into a shallow dive. First time it will be scary, but started high enough, you will survive. Just DO NOT do what the Aircraft guys do and start the roll climbing even a little. As long as you maintain forward speed, all the little fears about Revo mixing, roll rate, etc. will disappear.

Rolls can be done 'with the wind' or 'into the wind'. With the wind they will look smoother but started late, the heli may be a long way out before completion. Done into the wind, the roll will look 'pitchy' and erratic but will not travel as far. Having said that, I don't think it matters much.

Lets Get Started....

Just sit down and think about the sequence of controls for a bit and do some dry runs with your thumbs BEFORE attempting the roll in the air. As long as you do not panic you will pull this off with no sweat.

For the faint of heart, start as high as you can and as fast as you can. The rest of you just follow these simple directions.

Make a big sweeping turn at the end of the field to conserve forward speed. Settle into a fast level pass at full throttle/collective, making sure you are NOT climbing. The faint of heart should actually be decending very slightly to come back into sight.

OK NOW...

Your level, your fast, the heli is right in front of you, your heart is pounding, Give it full aileron...Jeez, it seems slow doesn't it?...Can't fold now, in for a dime, in for a dollar

As it starts to roll, you should remember to give it full 'negative' collective (all minus 2 or 3 degrees), you can slam it this time, and work on technique in the future. It WILL come around, and it will NOT loose much, if any, altitude. As it starts to return to right side up, give it positive collective again and release the aileron when level.

The roll probably looked better than most aircraft rolls. With a bit of practice they will.

It won't be long now before you are trying consecutive rolls, split 'S's, Cuban '8's, reverse inside loops.....watch out Curtis Youngblood.

You have most of the tools to work with now. Learning what the heli can do at different flying speeds will take time and experimentation. So buy your fuel by the case and FLY.