Flying without a gyro ?

[gyroimunav]

The reactive torque changes in RC helis can be very fast, primarily due to headspeed, but also some large gusts. The reason this is not a significant in a much larger("Real") helicopter is because their changes in reactive torque don't happen as fast, althought the torque itself is much much larger. It's easier for a pilot to manage with the rudder pedals. The reason for this is simple. The yaw moment of inertia and other factors provide much needed yaw damping. This yaw damping helps keep the tail from any sudden jerks or turns. Imagine what would be much harder to swing, a stick, or a large "Conan the Barbarian " sword !!!...Another factor is that headspeed changes in larger helis are more gradual. No collective pumping in a real helis. Now there are some control systems on large helis that augment yaw control with a gyro and a yaw autostabilizer, but generally no. Rc helis generate very quick changes in reaction torque, especailly with todays lightweight frames and large motor output torque and power systems. Where else can you source 60A to a DC motor with such a small, lightweight battery? Most bench top power supplies cant do that. In short, not impossible but not worth losing your $600 heli over. As with anything, you could learn to compensate, but why..It's there to allow you to enjoy the flight while not always fixated on keeping er doing on the right direction. Forward flight would be less of a challege without a gyro. And good luck with any 3D without a gyro! Might be fun to try out on a smaller less expensive piece of crap heli.

[jauguston]

I'm, a old guy just getting back into heli flying with a 450 EXI. In the early 80's I flew a GMP Cricket and then a GMP Competitor 60 that was fully aerobatic by the standards of the day. There were no gyro's. It makes me chuckle to read post after post about how the cheap gyros are bad and you have to have the expensive one if you expect to fly well --- BS! Gyro's have just made heli flying possible for a group of folks that don't want to or don't have to dedicate the time to REALLY learn to fly a RC heli (-:

Does my EXI have a gyro -- damn right

Regarding the comment that full size helicopters don't have gyros that isn't exactly true. They have the most sensitive gyro there is it is called "The seat of your pants feel".

Jim

[gyroimunav]

3D without a gyro would be very challenging and all good pilots are generally taught not to fly by the seat of your pants because your little gyro in your inner ear called your vestibular can lie to your brain about your orientation and motion. It may be sensitive, but actually it is prone to spatial disorentation. Here is an example..Try letting off the brakes in your car, after you've stopped, and look at the floor board. After a few seconds, you wont sense motion because your not accelerating. You may have to try your experiment a few times. Newton said F=MA...No acceleration, no force...Luckly for us we have visual information that overrides vestibular information to your brain quickly when you pick your head up and generate a ref image frame of motion. This is generally true with aircraft, maybe less so with helis. I don't fly helis, but I'm sure heli pilots can tell you about SD in the night when the visual info is not there to counter the vestibular.

[jauguston]

Interesting presentation. What it has to do with what I said I am not sure.

Jim

[gyroimunav]

Jim, how did the GMP fly back then. Were they gas/electric? My first heli was an EXI 450. Are you running stock, or did you upgrate avionics? It's not a bad heli for the price.

[jauguston]

Both of my GMP's were nitro motors. The Cricket had a OS 25FSRH and the Competitor had a OS 60 FSRH. You need to remember back then (early 80's) there weren't the batteries you have today and electric helicopters didn't exist. There wasn't a lot of fixed wing electric flight either, some but nothing like today.

The Cricket was FP but the Competitor was collective and fully aerobatic. I could most things done today but not some of the really wild stuff. I could for example do inverted hover 360's. I am curious how much if anything I remember from back then. I have not flown the 450 yet, no radio, Waiting for a Hitec Aurora 9 2.4.

Jim

[gyroimunav]

Yeah I think I was thinking of the old "skylark". Not a GMP, but first electric heli I think.......I think a lot : )... Well I'm sure with a few practice runs, you'll get back in the saddle. That brain will kick in and you'll remember what it was like, plus todays helis are more stable and have a little bit better engineering. 450 was a good size for me starting out. If you stay in the hobby a while you may end up getting a larger heli. A little more stable in yaw, and lots of power. I just bought a TREX 500 ESP..

[CharlieMF]

Learned on a Kavan Jet Ranger with a Webra .61 blackhead for power in 1976. Kraft 7 channel radio, there were no heli radios then. Mechanical mixing via adjusting where on the servo wheel you put the output and the collective servo moving a tray with the two cyclic servos on it. You could get the mixing okay when adding power but it wasn't equal when you came off the power, also if you got into trouble and had to add a lot of power the tail would swing with the torque. Needless to say slow collective inputs and smoothness were the order of the day. It took me almost a year to learn to hover with floats on and on a buddy box, with my mentor, just on weekends. Your mind was so taken up with controlling the tail that you didn't have much left for anything else. It was such a treat to finally be able to just fly around. We ran a full tail fin then that was a bit oversize for the weathervane effect and in FF you didn't have to worry about the tail, but when you transitioned to land you had to be overly smooth on the collective or she would turn on you. The fear of the landing was always with you when you were flying around.

[Dusty1000]

Here's another vid (by guess who) where he hovers a King2 without a gyro - right at the end of the vid

[ame]http://www.youtube.com/watch?v=3OAgZfhzoWI[/ame]

A King2 has a very slow tail though, the only way to get it to yaw anywhere near fast is to upgrade it. I remember someone on another forum saying he had struggled to learn to hover his King2, and by the time he eventually managed he realised that the gyro had never worked (he did eventually buy one). So if anyone fancies trying a heli without a gyro, I would guess a King2 would be a good heli to try

Dusty

[jauguston]

You can learn to fly heli with any of them available today without a gyro --- its just harder You can learn to fly heli without a gyro OR a heli radio but WHY

If it was not for the development of inexpensive gyros and good heli radios you would not see the market for helis you see today. It is sooo much easier now. Not easy-just easier.

Jim

[tintoy]

Originally Posted by Kington99

not sure about more advanced machine but i've flown an R22 which deffinitely did not have a gyro or any kind of computer stabilising. I think they can get away with it because their performance envelope is so limited, if you applied heavy collective it would start to drift round slowly and require a slight touch on the pedals to hold it straight again.

I think some millitary helis (black hawk etc) now have gyros;

http://news.google.com/newspapers?ni...g=6728,4609079

Although this suggests they are not nessecarly used for tail pitch control, but control (in this case) a stab on the tail - i presume horizontal, as they refer to it controlling the helis pitch in flight

http://findarticles.com/p/articles/m...9/ai_n6355431/

[Finless]

Of course you can fly a heli without a gyro! As many older guys have said back in the 80's there were no gyros!

I had a GMP Cricket fixed pitch and could loop it!
My CP machine was a Kalt Baron 20 and you could loop and roll it no problem. Even auto rotations. People even learned inverted hover with no gyro. Some used a reverse switch on the radio to reverse the tail and elevator so hovering inverted was the same as upright. Some learned to hover inverted like today. Learning the backwards controls.

Also there were NO SIMULATORS back then so you learned by doing!

So anyone that says it cant be done doesn't know what they are talking about. Sure I doubt seriously that you would be doing the kind of 3D flying you see today (prio flips and other demanding maneuvers) but certainly basic aerobatics is possible without a gyro. I know I did it! Many did it!

Here is me with my GMP Cricket with NO GYRO circa about 1982.



Bob

[jauguston]

Bob,

That could be me with less hair and more bulk (-:

These young whippersnappers missed the true beginning of heli flying(-:

I had a Futaba transmitter that had a reversing switch. Inverted flight and hover 6" from the grass was something I could do with the Competitor 60 then w/no gyro. It will be interesting if I can do it with all these new goodies. At 70 years of age my reflexes are not like they used to be.

Jim

[gyroimunav]

Thats awesome Bob!...Kinda funny, but definitely awesome. I would assume it was a little easier to fly without a gyro back then compared to now primarily due to the increase in Power/Weight ratio, but then again I think helis these days have more tail authority. As far as the differences, how do they stack up? I would be interested in what has changed the most over the years? ....

[drrm123]

You can fly without a gyro just use the programmable mixing on your radio. The one that your always instructed to turn off when setting up your gyro. Almost the same as setting up pitch and throttle curves. When computer radios came out that's what it was used for after the old days of doing it mechanically. I never did learn to fly very well back then.

[gyroimunav]

Yeah, forgot about that thing...Thats funny. How well does that work...Never tried it.

[jauguston]

Can we change gears for a minute.

Lubrication. What needs to be lubed and with what and what should NOT be lubed. I know my Hobby Partz $11.70 motor bearings are supposed to be lubed but I don't know how often or with what. I think it takes some kind of a needle oiler. Where do I get one of those? Is something like synthetic 5-20 oil OK.

I got to take my HS65MG servos back out today after watching Bob's video and realizing they WERE tight in the CF frame and the bolts WERE crooked. One more disaster averted (-: Thanks Bob!!

Jim

[HoverHeaven]

I learned to hover my first heli, a semi-scale Graupner Bell 47G (about the same size as my Trex 500) without a gyro, back in the late '70's. I too used the "piece of string tied to the tail" method, and I remember it took me well over 12 months to learn to hover and keep the tail reasonably straight!

First gyro I ever bought was in the late '80's, a Futaba 152 which was all mechanical (!), with a small brushed motor and 2 small flywheels inside.

This was a revelation in its time and completely transformed the controllability of my helis, but compared with modern gyros, was extremely basic.

I currently use 2 Futaba 401's and 5 Spartan 760's on my fleet - for years now I have never even thought about "real" tail control, but I bet that with a bit of practice, I could still fly any of my helis without a gyro..

So, to those of you who say it can't be done, YES IT CAN !

[Finless]

I remember also getting back into helis for a SHORT run in the mid to late 80. I bought a concept 30 and the hobby store insisted I buy a gyro! At the price at the time it was like... "YOUR KIDDING ME RIGHT"? I don;t need no stinking gyro!

I showed up at the field with my Concept 30 and no gyro and all the guys freaked out! WHAT? No gyro? You HAVE to get one... I proceeded to fly just fine with no gyro and in fact showed a few of those guys up in the process.....

FYI the radio mix of pitch to rudder was NOT just for no gyro setups... Back then the gyros that were out were not heading hold but rate mode gyros and you still used pitch to rudder mix...

When I got my Concept 30 I still only had a old airplane radio and set it up OLD school with Y cables and mechanical offset for throttle to pitch ratio... The guys with all the fancy radios then were freakin out! Surprised I could fly it
Not trying to brag or anything here but the truth!

Bob

[gyroimunav]

Bob, just curious..How long has it been since you've had a heli crash? ..what happened and what was the result?..You've been flying for a while, just wondering how less often it happens..Thanks