Rotorcraft Power

[Desert Rat]

Greetings fellow Rotorheads..
I've been reading lots of posts about Gyro powerplants and have a question for you all?? I live in New Mexico. We are typically at 4800 MSL and above, with summer temps in the high 90's. It has been difficult to determine how much power is needed to safely fly at this elevation. I know that the Ultralight gyros out there, ie.. Gyrobee will be pretty marginal at best. I like the Dominator design. I'm not really sure if even a blue head 582 has enough umph, especially at my 215 lbs. Losing weight is not really an option since I'm 6'6" tall. I've also heard good and bad about the Subaru... I know they are heavy and wonder if this has enough power with a redrive.. Any help and opinions would be greatly appreciated. Thanks to you all...Desert Rat

 

[mark treidel]

Mike, I fly a 912ULS Dominator. Our airport msl is 5512' standard. Most times the D/A averages above 7500'. It is nce to have that power available when needed but in the summer, you need it all at this altitude. Also figure an additional 2' of rotors over the recommended sea level lengths. Suburu at this altitude is a pig. 'Racer' here on the forum has some fantastic sled engines also.

 

[Desert Rat]

Thanks Mark,
Truthfully, I forgot about the 912.. I know that it is an ouch to the pocketbook too. I saw a thread about a Dominator builder in Colorado who had a Suzuki engine. Any idea if this panned out?? Very nice Dom you have there Mark. What size rotors do you fly?? Thanks, Mike

 

[Friendly]

I think the 582 would be a better option than the soob motor. The hp gain would not be enough to offset the weight gain. Then you need more rotor to pick it all up. The best defense against Gravity is to loose the weight. My 2 cents.
And as mentioned the engine by Todd in Colorado does look promising at this time.

 

[GyroDoug]

Mike,

I very much understand your situation. I am a 230 lb pilot flying out of a 5,000 ft altitude runway (here in Utah) in the Rocky Mountains. On a nice summer day we are looking at density altitudes of 7,000 to 10,000 ft. which means you are losing 30% of your normal rated power before you even try to take off or fly any higher. If you are going to do that you simply need to have way more power than you would otherwise need or need to use a turbocharger or supercharger. I am going the Rotax 912 route with a custom turbo and intercooler on it, but that is a pretty expensive option. The Yamaha 120 HP four stroke conversion that Racer is selling is a very logical solution that will cost a lot less than the route I am going. There are of course other options but if your not a designer and machinist and ready to do a lot of work yourself to create a custom job, going with a package deal like Racer offers makes a lot of sense.

I hope you will plan on coming up to the "Rotors Over the Rockies" on June 10 - 12 in Brigham City Utah. (you can find out more info. at our webs site at "utahrotorcraft.org") This will be the closest opportunity you will have to attend a major Rotorcraft gathering. It will give you a chance to see some different machines and how they fly at this higher altitude. June can be cool or can be hot here in Utah so you never know what the weather will be but I'll bet it will be cooler than New Mexico that time of year. We would love to have you join us for those 3 days.

Please let me know if you have any questions that I can help with.

Doug Barker
PRA Chapter 2

 

[mark treidel]

Mike, I fly 26' D/W's.....at this altitude and 750# AUW, I use every inch of them. I could actually use 27's in the summer but still manage ok w/o them.

 

[gyromike]

Greetings fellow Rotorheads..
I've been reading lots of posts about Gyro powerplants and have a question for you all?? I live in New Mexico. We are typically at 4800 MSL and above, with summer temps in the high 90's. It has been difficult to determine how much power is needed to safely fly at this elevation. I know that the Ultralight gyros out there, ie.. Gyrobee will be pretty marginal at best. I like the Dominator design. I'm not really sure if even a blue head 582 has enough umph, especially at my 215 lbs. Losing weight is not really an option since I'm 6'6" tall. I've also heard good and bad about the Subaru... I know they are heavy and wonder if this has enough power with a redrive.. Any help and opinions would be greatly appreciated. Thanks to you all...Desert Rat

Rat,

Paul Watson, RockyMeLad here on the Forum, flies out of Las Cruces. I believe the elevation is similar. He uses a 60hp MZ202 and 24 foot rotors on the Desert Bee and seems to do fine with that setup. He's not a small fella either.

I'll bet that a 582-powered gyro with 24 or 25 foot rotors would work for you.

 

[Rehan K.Janjua]

Have an Air Command 582 single seat, 25ft Skywheels,68" Warpdrive
all options including side tanks and 14lbs battery.

I weigh 185lbs and am 6'2".

Base elevation 5500ft, DA could reach 7500ft plus.

Power is OK with fresh fuel and low heat/humidity.

Wishing for a Suzuki G10 with 2.62 Rotax C type gear.

Regards

 

[Desert Rat]

Thanks All for your answers to my question. I guess I have some more research and thinking to do about this. As Rehan says " Power is OK..." and I'm at 215 lbs... The 582 does sound good..I just don't want to be on the edge. The 912 would be best as you say, but the $10,000 price tag is a little too much. Maybe I can go visit Rocky and check out his set up... I have a nasty worn out Suzuki G13B complete in my Brothers hanger. I pulled it out of a 2000 Swift. Probably would be good in a 2 seat fixed wing. Thanks again for all your helpful input. D Rat

 

[raven-rotor]

Rob Oberbreckling put one of our 90 HP G13BB Geo/Suzuki engine conversions on a dominator and was flying at over 5000 ft. elevations here in Colorado. He's posted about it somewhere on this site. Plenty of performance and reliability. Since you already have the engine you could put one of our kits together for about $5K and have a good package.

We've also converted the Suzuki Arctic Cat 660 turbo 120HP and its a rocket, even at altitude but you will spend more money. Most powerful engine we've tested as it will outdo 914 Rotax at third the price!

Feel free to call me with any questions.

Hope this helps.

Jeron Smith
Raven Rotorcraft/ReDrives Inc.
575-737-9656 cell 303-440-6234

 

[GyroDoug]

I wish!!!

I wish!!!

The 912 would be best as you say, but the $10,000 price tag is a little too much. D Rat

If only you could buy a Rotax 912 for $10,000!!!! New they will be nearly double that amount. (and people still buy them left and right) I bought mine used, got a screaming deal and still paid more than that. That's why so many people (flying Gyros - at least) go with alternative engines.

 

[Desert Rat]

Yes the Raven conversion sounds good. There are a number of others doing the same thing... As far as $20,000 for a 912..well I would have to be locked up in a looney bin for a long time if I paid that... I just don't see the justification in charging so much for an engine. They seem to have us right where they want us on this... by the nutsack. just my 2 c' worth.. D rat

 

[Brent_Brown]

Desert Rat I have a DCDI 670cc rotax if you want it let me know maybe we can make a deal? Why am I selling it? I want to get my twinstarr gyro flying.