Hornet,Bensen,Air Command or KB-2?

Sanko26

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Hi guys!

I'm 242 lbs and I want to have 8 gallon fuel on my gyro. Which one can fit to my expectations? And comparing to them which one is the most pilot friendly gyro? Thanks!
 
Are you going to fly off a runway or grass or both?
Are you using this for fun flying around your base, or are you planning on using it to go cross country?
Have you had any gyro experience or training, and have you looked at how to get training?
Are you planning on building this yourself, or buying it already built?
What engine are you planning on using?
 
Are you going to fly off a runway or grass or both?
Are you using this for fun flying around your base, or are you planning on using it to go cross country?
Have you had any gyro experience or training, and have you looked at how to get training?
Are you planning on building this yourself, or buying it already built?
What engine are you planning on using?

Thank U for your quick answer!

I will use grassy airfield only. I plan to use it cross country as well. I have no gyro experience at all, but I know training center (little bit far from my town). I will build by myself at home.

I am paratrike pilot and aircraft technician. I have machinery for building. I've built trikes,paramotors etc., but I'm new in the world of gyroplanes,that's why I have a lot of questions. I want to build what is the perfect for my aims. I have Rotax 503, 532 and Suzuki G10 engines at home,but I don't know which one should I use for the gyro. I would prefer G10. So?
 
Just my opinion, but wanting to fly @ your weight of 242#, having 8 gallons of fuel available, & flying off of grass, the 503 & G10 don't have enough horses to fly a gyro well @ all. The 532 possibly, if you can stand the power band in the critical phase of taking off as well as flying around in cruise rpms.

This is assuming the G10 is the 3 cylinder, 1,000cc Suzuki automobile engine. Supposedly putting out about 60 hp. The extra horses it puts out over the 503 is negated by the weight of it being a 4 stroke engine.

The "coming on" of power of the 532 in the rpms just when you want to cruise around, and particularly annoying, when you are nursing up the rotorblades to flying speed prior to lifting off. Sudden jump in rpms makes for too much airspeed, which results in too much air flow introduced into the rotorblade disc, causing them to quickly flap, which onsets so fast that cutting throttle & moving the stick forward to level the disc is immediately required to avoid damage.

I don't have the experience of flying an 532, but have heard of other's problems in this area. I do have experience in flying a gyro w/ the 503. Weighing about same as you, w/ the same amount of fuel, it is painfully lacking in reserve power. This is near sea level. A 503 on a gyro works much better w/ a pilot @ considerably less weight, as well as carrying less fuel. I found the 503 was fine as long as I kept the fuel around 2-3 gallons. This was flying a set of 25' rotors. Apparently, trying to carry those extra 5 gallons was past the tipping point of having peppy engine performance vs. flying a slow dog.

Any 2 stroke engine in this hp range gets about half the distance in fuel consumption flying a gyro than trikes or light airplanes, due to the huge amount of drag created by the rotorblades to fly around on. The trike wing & airplane wing is about twice more efficient due to the wings.

The trade-off w/ flying rotorblades on a gyro is the lack of dangers of stalling. Extremely more maneuverability, too. Ease of transporting a gyro on a small trailer & little time required to assemble & mount the rotorblades, compared to the time needed to get the trike wing ready to fly & then to disassemble afterwards to "unfly". All that isn't a problem if you can fly out of wherever you store your trike, airplane, or gyroplane.

When I switched to the Yamaha snowmobile engine (3 cyl. 998cc, carbed), all those problems regarding lack of power & ability to lift my weight & to carry 8 gallons of fuel went away. Excess power. I don't even use all that is available.

It actually scares me to leave in full throttle for more than lifting off & climbing out a few hundred feet, because of the speed that builds so quickly! I want to live to be an old pilot, & don't care about being a bold pilot!

And, due to the pitch of the prop (about 13 degrees), I don't use more than 90 hp. That Yamaha engine is rated by them @ 115 hp. Redline is 10,500 rpms. My prop-limited rpms are 7,200.

I have flown it to 100 mph, where I chickened out, because of how much I could see the rotor disc was down in front of me to achieve that speed. I was wondering where the line was in terms of the rotorblades tucking under the airflow. In an open frame gyro, flying @ that speed, there is tremendous airflow trying to remove your helmet & press you back into the seat. Uncomfortable.

It is much more enjoyable to fly along in an open frame gyro @ 45 mph-55 mph. Feels just right. In the groove, just like driving a motorcycle on a fine day! Probably just like flying a trike, from what I've heard speaking w/ trike pilots!

Flying along @ those cruising speeds, the Yamaha 4 stroke engine uses less fuel than a two stroke. No 2 stroke oil used, & using regular octane gas, vs. premium gas & a good-quality 2 stroke oil highly recommended for 2 strokes.
 
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Good advice from both John & Kevin.
Also, you will not be stuck on the ground waiting for winds to die down, our blades cut through turbulence as if almost not there.
We are asked not to come to fly at the PPC meets at the Salton Sea because it makes them feel bad that we are flying and they are all stuck on the ground until the winds die down. I understand, makes some want to switch so they can fly more when they have the time but not the winds.

PS:
Shameless plug, I'm known for...
You can win a zero time 65Hp 582 Rotax aircraft engine from PRA's raffle for only $20.00. We only have from 50 to 300 people in our raffles and the best odds of actually winning!!! Only 3 in the raffle for the engine the last time I looked. It tells you on the page how many people our in each raffle.
And we love to give things away. https://pra.org/Raffle10.aspx?i=3
Also, a giving away a 3-axis flight simulator for $10.00 & a 3-D printer and SolidWorks Cad software for $5.00.
 
I have flown it to 100 mph, where I chickened out, because of how much I could see the rotor disc was down in front of me to achieve that speed. I was wondering where the line was in terms of the rotorblades tucking under the airflow. In an open frame gyro, flying @ that speed, there is tremendous airflow trying to remove your helmet & press you back into the seat. Uncomfortable.

Kevin, I think Chuck B., JC, et al smart guys have dispelled the concept of "blade tuck" as not possible...

Brian
 
I have flown it to 100 mph, where I chickened out, because of how much I could see the rotor disc was down in front of me to achieve that speed. I was wondering where the line was in terms of the rotorblades tucking under the airflow. In an open frame gyro, flying @ that speed, there is tremendous airflow trying to remove your helmet & press you back into the seat. Uncomfortable.

In my opinion rotor blades will not be “tucking under the airflow” at any speed.

I recommend against exceeding the manufactures Vne (velocity never exceed).

Most gyroplanes will behave in an unexpected way at some indicated airspeed.
 

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Guys! Thank U for the advices! I can easily purchase motorcycle or Subaru engines here. If U suggest I need a more powerful engine. But which type of gyrocopter can carry a heavy engine and pilot and 8 gallon fuel?
 
In my opinion rotor blades will not be “tucking under the airflow” at any speed.

I recommend against exceeding the manufactures Vne (velocity never exceed).

Most gyroplanes will behave in an unexpected way at some indicated airspeed.

Being ever so much more nose-down as speed increases, looking at the ground through the lowered rotorblade disc w/out let-up is very uncomfortable. I understand & think it is fun to see through them during sharp banking turns, but not continuously in straight flight & @ 100 mph...
Vance, you quite possibly do that a lot during your airshow routines?
 
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Get the Yamaha YG 3 sled engine 130 HP nice flat torque curve, fuel injected, plenty of power, and burns less fuel than a 582!
 
Being ever so much more nose-down as speed increases, looking at the ground through the lowered rotorblade disc w/out let-up is very uncomfortable. I understand & think it is fun to see through them during sharp banking turns, but not continuously in straight flight & @ 100 mph...
Vance, you quite possibly do that a lot during your airshow routines?
For folks who also fly helicopters, it is a complete non-event, unnoticed, to look through the blades.

You simply can't horse a gyro rotor disc suddenly forward while holding level flight so that you force reversal of flow, so it is not a realistic fear.
 
Being ever so much more nose-down as speed increases, looking at the ground through the lowered rotorblade disc w/out let-up is very uncomfortable. I understand & think it is fun to see through them during sharp banking turns, but not continuously in straight flight & @ 100 mph...
Vance, you quite possibly do that a lot during your airshow routines?

I used to imagine that The Predator flew more nose down the faster I went.

I put an inclinometer on her and discovered it was only a few degrees.

Nose down may be problematic with a pod like the Predator has.

If you are not comfortable flying fast then don’t fly fast.

I only suggest you don’t blame your discomfort on something that is not likely to happen.

Eighty five knots (100 miles per hour) is plenty fast.

I typically fly cross country at somewhere between sixty five and seventy knots even though I have a windshield.

I make a high speed pass in my airshow routine and typically see a hundred twenty knots of ground speed and peg the airspeed indicator at what appears to be a hundred twenty knots. (Once around and about fifteen knots of indicated air speed)
 

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When I switched to the Yamaha snowmobile engine (3 cyl. 998cc, carbed), all those problems regarding lack of power & ability to lift my weight & to carry 8 gallons of fuel went away. Excess power. I don't even use all that is available.

Kevin,

Did you install that engine on your Vortex/Lightening? Was it a difficult swap? I bet that much power is a blast to fly!

Eric
 
For folks who also fly helicopters, it is a complete non-event, unnoticed, to look through the blades.

You simply can't horse a gyro rotor disc suddenly forward while holding level flight so that you force reversal of flow, so it is not a realistic fear.

Yes, WaspAir, this is most likely that. I have concluded that if a segment of flying isn't comfortable, then I won't venture there.

I also have a fear of heights. That fear keeps me down low while flying. I am afraid of getting run over from behind by a fast airplane while out flying. I realize that we who fly small, slow aircraft (40-100 mph) look like a gnat against the sky to faster airplanes. I have been in small airplanes where the pilot doesn't even look out to the front where he was going, due to the instrument panel & engine being in a lot of the way.

About the only time I observed any of them look out to the front was preparing to land, where the view changes considerably forward. They usually look out to the side or look/talk w/ passengers. One fellow consulted his charts for a couple of minutes w/out looking up. I believe the arrogance of thinking they are the only aircraft anywhere near them also plays into this.
 
Kevin,

Did you install that engine on your Vortex/Lightening? Was it a difficult swap? I bet that much power is a blast to fly!

Eric

Eric, I did not. Todd Rieck in Colorado did the conversion that he used to sell as a kit. He placed a 2"x6" piece of 6061 on edge on top of the stock SC engine mount strut. That way the original 68" prop still had good clearance @ the keel, so that the stock engine support mounts weren't changed.

His conversion encases the Yamaha engine, sort of like our rib cages do. This is unlike all the others seen. That encasement is overkill, by his own admission. It also has another attachment to the mast up a bit higher than the engine, so that the thrust is pushing against the mast in two places, instead of the usual one where the horizontal strut comes out from the back of a mast.

I reiterate (like I have done previously) that changing to this engine was not w/ the knowledge or support of SC. I know we fly experimental aircraft, & do not think that SC is responsible for anything I do to a kit they manufactured & sold. Jim Vanek & Evan both suggested I make changes to the installation after they saw me flying the machine. Both ideas were ways to strengthen the mast system. I took their advisement w/ care & gave their ideas a lot of thought.

The power IS incredible. I found the most fun flying on the backside of the power curve close to the ground. I guess flying nose-high @ slow speeds gives me that "helicopter" experience w/out having to get a heli rating, nor purchasing a heli. I would float along a few feet above a dry lake bed, & when some sage brush plants "came along", I'd add slight throttle to go up enough to clear them, & then throttle back to descend back down. Then, add throttle to arrest the descent, then reduce throttle to maintain the original attitude.

Doing that gains lots of experience on how much rudder, stick, & throttle was needed to achieve the slowest flight regime possible. A slight puff of wind from the side can upset that balance, as well as from both the front or behind. Comparable to balancing on the mains where a little puff of wind can upset that balance point while doing so.

Landings while flying like that are slow speed & gentle. Almost helicopter-like. A little wig-wag of the rudder just prior to touching down creates a bit of additional drag on the airspeed, & slows the gyro even further.
 
Martin Hollmann was very tall man almost 7 ' and weight around 250 lbs ,he flew his bumble bee with rotax 447,you can find video online ,but the question is what altitude is your airport and how light airframe you can build .
 
Martin Hollmann was very tall man almost 7 ' and weight around 250 lbs ,he flew his bumble bee with rotax 447,you can find video online ,but the question is what altitude is your airport and how light airframe you can build .
Ohh man! Thank U for your answer to my question! I started that thread to discover which gyro would fit to me,but everybody started discussing about other flying issues 😀. My airport is on 300 ft AMSL, so it,s not an issue. I have the plan of Gyrobee and it's written in the design consideration that it's originally planned for 447, you can put 503 onto it, but you shouldn't mount bigger than 503 onto it. Even if the payload is 250 lbs. That's why it was strange to hear that maybe the 532 is also weak.
 
PRA is working with San Diego State University senior CAPA mechanical engineering students on an 80/85 HP Yamaha engine adding a reduction drive.
It has a better power to weight ratio than a Rotax 582 with only 65HP and better fuel consumption. Important with only 8 gals of fuel.
It will be delayed because SDSU has shut down the machine shop.
However, I have a few pictures that will help you understand/see how Yamaha motor mounts are different.

These pictures are too large to upload so made them links but the forum has made them landscape and no way to rotate it here. The originals are not landscape. Odd!!!



https:///pra.org/images/EdKits/85HpYamaha/20200315_213940.jpg
The aboce is right-side up go figure.
 
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