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<strong>Gasser</strong> <strong>Heli</strong> <strong>Project</strong> <strong>Final</strong><br />
Fine Tuning and Conclusion<br />
By Gus Garcia<br />
03/13/10<br />
Fly any kind of aircraft long enough and you begin to develop a preference on how you do your setup. It’s the<br />
same thing for helicopters regardless of whether it’s glow, gas, or electric, or what kind of flying style you prefer.<br />
For me, I’m old school and 3D is just a little too radical, I really enjoy big air sport flying using all available airspace<br />
afforded to me. I see some guys doing loops, and it looks more like a dot than a loop? I on the other hand like<br />
doing my loops so big, that they’re Lord Humongous loops. Hey but the cool thing about our hobby is if it floats<br />
your boat, who can argue with you?<br />
And the point of this is? Fine tuning the gasser heli for my preferred flying style, and getting it to fly the way I like.<br />
I have put together and flown so many helicopters throughout the years that once I finish putting one together, I<br />
go by feel and sound once I’m at the field to fine tune my machine. So let’s start first with feel – for big air sport<br />
flying I like smooth control response for stable flying, and the way I achieve that kind of control response is by<br />
setting up the dual rates and exponential to limit the jerkiness and smooth out the control response at center<br />
stick. On my Futaba radio I usually set the dual rates anywhere between 65% to 75% throws and negative fifteen<br />
to twenty percent (‐15% to ‐20%) expo, with this setup the best way I can describe it would be like riding in a<br />
Lincoln Town Car, it floats on the road – very smooth.<br />
I don’t normally use a governor for my throttle corves or tach to check my main rotor head speed, or even a temp<br />
gauge to check how hot my engine is running. Don’t get me wrong, these are all great things to have (and if you<br />
need them – get them), but once you’ve become a true Jedi Master and are one with the force (in‐tuned with<br />
your heli), you don’t really need them. Yes it does take the newcomer a little longer to setup/fine‐tune a new heli<br />
without these things, but once again in keeping with the gasser project theme, we won’t go into how to use these<br />
items. But rather explain the settings to get the gasser just right for Master Jedi Gus type flying…<br />
Had enough of the Star Wars quotes? Actually engine break‐in and heli fine tuning are done at the same time. As<br />
I’m break‐in the engine I’m listen to RPM and checking for temperature (by how the heli feels, sounds, and<br />
responds), and thereby adjusting the throttle curve to set the RPM to where I would like to have it (in the 1800<br />
RPM range for the gasser – it’s sweet spot), and/or adjusting the high and low carburetor needles (I prefer to have<br />
it a little towards the rich side). Once I have it where I feel it’s right, I’ve had guys in the past check my main rotor<br />
head speed with a tach and found it to be off only by 100 to 200 RPM – not bad, right? The point is if you begin to<br />
listen to your machine long enough you can start to interpret what it’s trying to say to you (you get into the feels<br />
right sensation). Again, this works great for me, you however may need to use instrumentation/equipment to<br />
achieve the same results, and that’s absolutely ok (whatever works).<br />
Anyway, after fine tuning the gasser for big air sport flying and smooth control response with an average head<br />
speed of about 1800 RPM, and the engine a little towards the rich side, the gasser is done! So how does it fly? Let<br />
me tell you, have you ever had a super cold bear on a hot day, it’s so good! Well it’s like that; this gasser is big<br />
and surprisingly nimble for a big heavy machine and it can do some mild 3D maneuvers, you won’t be winning any<br />
3D contests with it, but very nice for sport flying, or as a stable camera ship, it can move too. Its mass and weight<br />
help it achieve impressive forward flying speeds as well, and seeing it zoom by at 60 to 70 MPH demands respect.
Owning and operating a gasser requires more maintenance, it’s not just charge the batteries and fly. The forces<br />
excreted on a machine of this size along with the power, torque, and vibration of the engine will put a beat down<br />
on the helicopter’s mechanics thereby causing accelerated wear and tear. In the two gallons of fuel burned<br />
during the engine break‐in and fine tuning phase, I’ve had the main gear striped, the bolts to clutch shoe snap like<br />
twigs, and I go through canopy grommets like candy, the vibration of the engine keeps slicing them apart. Parts<br />
failure is a problem in itself, I just can’t run to the nearest hobby shop to get them (no one carries Century parts); I<br />
have to order them from the distributor in California. And unlike the nitro machines that become saturated with<br />
oil, the gasser has very little oil residue spewed over it, so it needs to be lubed and greased regularly.<br />
If and when it comes down (we all have crashes soon or later), I project the repair cost to be around the $500‐<br />
$800 range due to its brand (not all gassers are created equal). Is a gasser helicopter right for you? The answer is<br />
it depends on what kind of flying you like to do, and what justifies getting into such a big expense for only one<br />
machine? If you like 3D, then the 90‐size helis should be the one to get, if you like sport flying, then the 50‐size is<br />
the way to go, and if you really, really like scale, then the big gassers are great for that (big with heavy lifting<br />
abilities).<br />
With that said, guess what I plan to do with the gasser? Scale! Once I recover from its initial expense, and all the<br />
bugs have worked out of this machine, then a real nice Jet Ranger fuselage is definitely in its future. When that<br />
happens, I’ll be sure to chronicle its progress.<br />
I hope you all enjoyed reading about the gasser as it came together, and how it was presented. However, my<br />
approach is only one perspective, and not the only way of doing it. Actually I believe there are better ways then<br />
mine, and I welcome any and all suggestions, advice, and criticism, or if you have a project that you’re working on,<br />
and would like to have it spotlighted in the <strong>Heli</strong> Corner, and would like me to help you with that, then it would be<br />
my honor to do that as well.<br />
Flying RC helicopter is hard, complicated, difficult, and challenging. It is however not impossible, and if it beckons<br />
you to join our ranks, well then know this, we’re here to help you succeed and enjoy this segment of our hobby.<br />
The biggest failure in life is to fail to do anything, and not that you struggle with the task at hand, we can help.<br />
Will you accept our offer?<br />
Until next time, see you at the field – Gus.
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