World's Most Powerful Single Seat Gyroplane

I think this is kind of misleading.

The most powerful single seat gyro is the Bensen with a super Mac on it.

Weighs around 280 lbs
Horsepower is around 125-135
Weight to HP is around 2.10 pounds per HP. empty weight.

I was beging to think I was the only one with the right answer.
 
When have you ever NOT thought you had the only "right" answer?
Sucka!
 
I think this is kind of misleading.

The most powerful single seat gyro is the Bensen with a super Mac on it.

Weighs around 280 lbs
Horsepower is around 125-135
Weight to HP is around 2.10 pounds per HP. empty weight.

Thanks for joining the discussion, we're having a pretty good time in here.

I thought Super Macs were re-worked 72 HP Macs that made 90 HP? How does it spit out 135 HP? Are there any in use today?
 
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It was a Subaru 2.2 with solid lifters, roller rockers and a high performance cam.
It delivered 147hp to the prop, Dynoed.

I sold it to Waltchips here on the forum.

He flew it for a couple years and sold it to some guy in South America.

~~JAKE~~

So it may or may not still be running, outside the USA, no way to ascertain? Oh, well. I guess we are going to have to limit the discussion to that which we can verify for 2013, either way. Maybe our foreign brothers and sisters will chime in...

That certainly was an impressive machine! Thanks for the reminder.
 
Yamaha

Yamaha

While following this post I would have thought that by now the 4 stroke Yamaha powered gyroplanes would have been mentioned. I wonder why not? Anyone care to contribute?
 
A crock of bull squeeze !!

A crock of bull squeeze !!

I'll tell my side of the story if y'all will pick up my legal fees.

I was recently informed (by a Lawyer) that I would/could be sued for $500k if I didn't 'go away'.

My story would not be believed BY ME, had I not lived thru it !!!!!

fj
 
While following this post I would have thought that by now the 4 stroke Yamaha powered gyroplanes would have been mentioned. I wonder why not? Anyone care to contribute?

The current Yamaha powered gyros are 3 cyl. Greg's gyro is a 4 cylinder with more HP.
 
Value to us all.

Value to us all.

I'll tell my side of the story if y'all will pick up my legal fees.

I was recently informed (by a Lawyer) that I would/could be sued for $500k if I didn't 'go away'.

My story would not be believed BY ME, had I not lived thru it !!!!!

fj

I feel there would be value in telling your story Jim.

You don't seem like the sort to just "go away."

All the best my friend, Vance
 
Jim does your story relate somehow to this thread?
 
The Genesis

The Genesis

Yamaha's Genesis series of snowmobile engines are all 4 stroke engines. Some are three cyl. while others are four. Had a ride in Ron A's Yamaha/Dominator and boy could that bird climb. Can't recall my friends name, he's with the Morons, and his single seat is Yammie powered. So that's why I was wondering how Genesis gyros stacked up comparing hp to weight.
Farmer Jim, usually an individual is compensated for "going away". Did you get some "hush" money or what? Have a good day guys.
 
Jim does your story relate somehow to this thread?

My guess would be that Jim is referring to some of the comments made about the Turbo Golden.

I will try to say this in the most diplomatic manor that I know how.

Judging from some of the things that I saw up close and personal on Jim's bird I can understand him being less than 100% enthusiastic about claims made about the Turbo Golden.

However to avoid hijacking this thread I will leave it at that.

Marc
 
Good copy Defiantone!
 
Some observations on engines in flight.

Some observations on engines in flight.

I feel there may be some confusion between claimed horsepower and the horsepower actually available to do work.

Typically in The Predator when I climb out I see 2,450 rpm so I have 145 of my 160 horsepower to make thrust.

As I near top speed (95kts) solo I often just bump 2,700 RPM so I have the entire 160 horsepower available to produce thrust.

The size and efficiency of the propeller has a lot to do with how much thrust is produced by this 145/160 horsepower.

When the propeller is pitched correctly all of the gyroplanes I have flown will see well below peak power on climb out because they don’t climb out near maximum speed.

With Greg’s redrive ratio he is not reaching peak power because the propeller would be spinning too fast.

I doubt that he has more than 120 horsepower available as it is currently configured.

When I saw Greg fly his gyroplane at Bensen days it appeared to me he was using less than 100 horsepower.

Claimed horsepower and a claimed power to weight ratio may be fun fantasies but they have little to do with how a particular gyroplane will perform.

I see some wild claims for performance of gyroplanes that are compromised by the testing procedures. A popular gyroplane I have flown had an almost 20% error in the indicated air speed as we showed 90 miles per hour IAS.

Perhaps with some development Greg will be able to actually produce 150 horsepower in flight with his Yamaha.

In my experience more power for a given engine usually accelerates the wear.

Please understand I am not suggesting Greg is lying; only that he may be misinterpreting the application of numbers available to him.

Thank you, Vance
 
Yamaha's Genesis series of snowmobile engines are all 4 stroke engines. Some are three cyl. while others are four. Had a ride in Ron A's Yamaha/Dominator and boy could that bird climb. Can't recall my friends name, he's with the Morons, and his single seat is Yammie powered. So that's why I was wondering how Genesis gyros stacked up comparing hp to weight.
.


The single yammie @ Wauchula - I believe that is Brooke (Pilot Escort) with his Somma-yamma combo! Nice sounding machine!
 
my bad

my bad

Sorry to have 'diverted' the thread theme, it's just that when my bird was talked about in an ERRONEOUS, UNPROVEN & UNEDUCATED manner, I felt I should say something.

My apologies ! And Defiantone, you are a gentleman indeed.

fj
 
Please EDUCATE us Jim.

Please EDUCATE us Jim.

Sorry to have 'diverted' the thread theme, it's just that when my bird was talked about in an ERRONEOUS, UNPROVEN & UNEDUCATED manner, I felt I should say something.

My apologies !

fj

I feel it is exactly on the topic of the thread because Greg is claiming that he has the world’s most powerful single seat gyroplane based on his interpretation of numbers and the best power to weight ratio for a two place gyroplane.

It is my observation your published numbers are bigger than Greg’s and your gyroplane has been tested and it’s remarkable performance proven by a professional test pilot. A sustained climb of 2,200 feet per minute is remarkable.

Thank you, Vance
 
I feel it is exactly on the topic of the thread because Greg is claiming that he has the world’s most powerful single seat gyroplane based on his interpretation of numbers and the best power to weight ratio for a two place gyroplane.

It is my observation your published numbers are bigger than Greg’s and your gyroplane has been tested and it’s remarkable performance proven by a professional test pilot. A sustained climb of 2,200 feet per minute is remarkable.

Thank you, Vance

I think Vance the question is that it actually might not have been tested as claimed. You see every normally produced aircraft has its own series and Model. Jim's is sort of its own animal. So the rest results do not seem to apply.

I have seen some results of independent tests on the Golden that do not come close to those figures.
 
Twiggy B was tested.

Twiggy B was tested.

I think Vance the question is that it actually might not have been tested as claimed. You see every normally produced aircraft has its own series and Model. Jim's is sort of its own animal. So the rest results do not seem to apply.

I have seen some results of independent tests on the Golden that do not come close to those figures.

From Larry’s web page, frequently asked questions on the development of the Turbo Golden Butterfly.

"The Golden Butterfly is actually the third butterfly model that we developed right after the Ultralight 503 and the Monarch 582 models. I knew we would need a two place trainer to train people how to fly our gyroplanes. Training is the intended use of the Golden Butterfly to this day. The Golden and Turbo Golden were actually developed side by side as the first engine that I bought to design the motor mount was a 2002 WRX 2.0 Turbocharged engine. I wanted the finished airframe to be able to accept a turbocharged as well as the naturally aspirated Subaru engine.

After developing the engine mount we proceeded to build the first Golden Butterfly with a 2.5 Single Overhead cam engine with a cam grind that gave that engine about 190 hp at about 5,800 rpm's. We won an "Outstanding New Design" award at Airventure 2004 for the first Golden Butterfly built. We had already developed a four planet 2.18 ratio planetary redrive for the Subaru engines back in 1994.

The Golden Airframe was first developed for a 72" propeller although the 5,800 engine rpm limited the propeller diameter to 68" while using the 2.17 reverse rotation planetary reduction unit. This means that the engine is turning counter clockwise from the rear and the propeller is turning clockwise. This kept the prop tip speed to about Mach .7 at full throttle climb out which is loud but acceptable as most airplanes prop tip speed is about that speed.

At Airventure 2005 we introduced the first Turbo Golden Butterfly with the 2.0 DOHC WRS Turbo engine with 227 hp. On this engine we installed a 72" 4 blade propeller with the same 2.18 reduction unit. This made the prop tip speed at about Mach .78 which was loud and inefficient. I also learned that that 4 blade Warp Drive propeller was only good for about 200 hp efficiently.

It was a blessing to be able to test these two models side by side. This gives more data points from one version to the other for a more complete analysis as to how the airframe/engine/reduction/propeller combinations are working together. The extra weight of the turbocharged engine made the TG weigh about 175 lbs more that the Golden.

All testing is done with 5 gallons of fuel and a 200 lb pilot (that's what I weigh). All stated performance data is interpolated to a standard day at sea level. The Golden Butterfly would climb out at 1,600 ft/minute. The climb out with the 2.0 liter Turbo Golden was slightly less at 1,500 ft/minute. The Turbo Golden had another factor that I had to think about. At a high density altitude of 10,000 feet the TG would still have all the 227 hp but the propeller would need to have more pitch added so it wouldn't over speed the engine. If the pitch ever has to be set much above 15 degrees then the prop would be in stall for takeoff. It would only come out of stall after 40 mph airspeed is reached. If the 2.0 liter TG was flown at that high density altitude with full payload the performance would be ordinary. I knew from that time on that I would never sell another 2.0 liter WRX Turbo Golden because by that time Subaru had come out with a 2.5 liter WRX engine with a stated crankshaft 305 hp. This means 78 more hp for the same weight which would make the TG perform better than the Golden Butterfly.

The next step was to give the Turbo Golden airframe the capability to swing a 76" propeller and at the same time keep the tip speed down to the acceptable airplane Mach .7 number. After making this modification on the airframe we installed a 76" three blade Ivo Prop "Paddle Prop" made for airboats. These blades can absorb 100 hp/ blade. Since the stock 2.5 WRX Turbocharged engine puts out 305 hp at 5,000 rpm's and the tip speed with the 2.18 reduction was right at mach .7 this became our first production unit for sale and we sold our first kit of this model at Airventure 2006.

While installing the first 914 turbocharged engine on a Super Sky Cycle in 2008 I realized that the turbocharger was about two sizes larger than normal for that CC of engine. After some research I found out that an aviation engine has an oversized turbo so that when it goes to high altitudes the turbine wheels won't over speed and blow up. I then decided to oversize the turbocharger two on the 2.5 Turbo engines to aviatonize the turbo for higher altitude flying without the turbo fins over speeding. The boxer engines in the Subaru cars redline at 7,000 rpm's. After studying the WRX STI dino charts I also realized the potential of the WRX 2.5 boxer Turbocharged engine to easily put out over 400 hp. Not that I would ever boost our engines to that HP but to be able to add boost as HP is needed intrigued me. I knew we already had the airframe to handle that HP. I also realized the need for a gyroplane that could have a payload capability and a place to put that payload. By installing a larger turbocharger in place of the standard TDO4 and upping the rpm's of the engine up to about 6,500 rpm's for climb out that a powerful work horse gyroplane is possible. Now we have a redrive problem again with this scenario. The tip speed of the 76" propeller would be way too high with the 2.18 ratio. After searching gear ratios I found a SIX PLANET gear set with a 2.84 ratio that could be modified to fit inside my existing planetary unit. I also extended the propeller shaft on the redrive and installed a 1/2" thick shaft support to support the side loads of the larger 4 blade propellers we were about to install.

In 2008 we had some of the six planet 2.84 gear sets made. We installed the new 2.84 gear set in the prototype TG and the larger Left Hand turning 76" propeller. We also bumped the boost up to 300 hp. This ratio was so quiet while testing around the airport that the fixed winged pilots were asking, "What have you done to that gyro? We barely can hear that thing flying around it is so quiet." I knew then that we had a winner with this new ratio. A quiet propeller is an efficient propeller. I could take off at 6,500 rpm's for climb out and the mach number was the normal airplane noise level of mach .7. When I throttled back to 6,000 rpm's the mach number went to mach .64 which is about the same mach number of most of the Rotax engines like the 912S with a 68" propeller. When I throttled back to 5,500 rpm's for normal cruise the mach number went to mach .59 which means the propeller isn't making much noise any more. All you hear is the engine and the rotor blades. That is what the fixed wing people were excited about….low propeller noise. In actual fly over testing at 500' we were 10 decibels less than a Cessna 172.

In July of 2009 we bought the first high performance 2.5 short block and had a local drag racing mechanic to assemble our first production WRX engine for the larger turbo. We also bought an aftermarket larger intercooler. This combination with the six planet 2.84 reduction and a 4 blade propeller capable of absorbing up to 400 hp would be our current model from this point on.

In the fall of 2009 we sold the first aviationized 2.5 liter Turbo Golden gyroplane to a man in Liberia.

In the spring of 2010 we designed and made the first production run of parts for an electric Metro Launch System pre rotator for the Turbo Golden Butterfly. This would give us the capability to launch from a dead stop with full power and eliminate the need for a long runway. We also designed and built a plug on side extension platform for hauling cargo or for a mash unit for developing countries.

The performance of the smaller 190 hp Golden Butterfly is good. It can take off and land in a direct 30 mph crosswind. The fully flying tall tail is very powerful and is on a long moment arm from the center of gravity of the aircraft. It is a good training machine and we have given rides to people weighing up to 340 lbs. An independent test was done in 2011 by a major aerospace company using a Golden Butterfly. They wanted to know if a gyroplane using a car engine could carry a payload of 700 lbs. They purchased a TG metro launch system and a set of side plug on extensions with two 13 cubic foot aerodynamic car haulers attached. They successfully flew the test machine at a gross weight of 1,575 lbs. which proved that a gyroplane could haul a payload of over 700 lbs. without the need of an expensive aircraft engine.

The performance of the 300+ hp Turbo Golden is in a class all by itself. This is the most powerful power to weight gyroplane that I have ever flown. The static thrust at 5,500 rpm's is 800 lbs. at half throttle throw. At full throttle 6,360 rpm's the static thrust is over 1,000 lbs. This is nearly as much thrust as the TG weighs. The TG balances on the mains at 3,500 rpm's. At half throttle throw the gyro leaps off of the ground like a nimble single place machine. With a 65 mph climb out at full throttle (6,500 rpm's in flight), the MGL rate of climb gauge is pegged out at over 2,000 ft/minute. We are considering attempting a world record time to climb to 3,000 meters in this ship."

It appears to me that Jim’s specific gyroplane AKA (Twiggy B) was tested and her performance measured.

Thank you, Vance
 
Vance -

I too, found your post a very interesting read !

Funny how my Real Life experience was 1,00000000000000000000000000000 % different. (approximately )

fj
 
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