Does a Predator 670 have enough power to fly a Hummel Ultra Cruser with a 200-pound pilot?

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Carey

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I am trying to purchase an Ultra Cruser that is FAR 103. But to do this I am told that the 1/2 VW engine may be too heavy.
But the Predator 670 does not have enough HP to safely fly a 200-pound pilot. Does anyone have any real experience in the Ultra Cruser with either the Predator 670 or the 1/2 VW engine.
 

Bigshu

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I am trying to purchase an Ultra Cruser that is FAR 103. But to do this I am told that the 1/2 VW engine may be too heavy.
But the Predator 670 does not have enough HP to safely fly a 200-pound pilot. Does anyone have any real experience in the Ultra Cruser with either the Predator 670 or the 1/2 VW engine.
Look on you tube for Ultra Cruisers. You'll see a bunch of videos of them flying behind 1/2 VWs. Dennis Brooks did a video where he weighed his latest build and it was well under the limit for part 103. The Predators need some work to get up to the HP needed. Hummel has a V-twin ready to fly that they have used on an UC. Look for videos of that too.
 

Regdor

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I am trying to purchase an Ultra Cruser that is FAR 103. But to do this I am told that the 1/2 VW engine may be too heavy.
But the Predator 670 does not have enough HP to safely fly a 200-pound pilot. Does anyone have any real experience in the Ultra Cruser with either the Predator 670 or the 1/2 VW engine.
The Predator engine conversion was thrown together to provide a lower cost
option to get the bucks down guy a way to get airborne (just barely)....That solution only works for a short while until you get apprehensive about clearing the weeds and bushes.....The larger 1/2 VW has more margin and those who skimped on the performance parts initially soon opt for them as the bushes are no longer a problem but the trees are now too big....
 

Flyguyeddy

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The Predator engine conversion was thrown together to provide a lower cost
option to get the bucks down guy a way to get airborne (just barely)....That solution only works for a short while until you get apprehensive about clearing the weeds and bushes.....The larger 1/2 VW has more margin and those who skimped on the performance parts initially soon opt for them as the bushes are no longer a problem but the trees are now too big....
The factory plane seemed to get off the ground quite well.
 

billyvray

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I am trying to purchase an Ultra Cruser that is FAR 103. But to do this I am told that the 1/2 VW engine may be too heavy.
But the Predator 670 does not have enough HP to safely fly a 200-pound pilot. Does anyone have any real experience in the Ultra Cruser with either the Predator 670 or the 1/2 VW engine.
Recall, the predators that get used are typically not bone-stock. They use billet rods, lighter flywheels (or no flywheel), no governor, and turn up higher than stock rpms with belt redrives.
 

galapoola

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I am trying to purchase an Ultra Cruser that is FAR 103. But to do this I am told that the 1/2 VW engine may be too heavy.
But the Predator 670 does not have enough HP to safely fly a 200-pound pilot. Does anyone have any real experience in the Ultra Cruser with either the Predator 670 or the 1/2 VW engine.
My dad flew behind a 1/2 VW for 500+ hours. He's 6'2" 180lbs. I believe it was a 37hp. Never a complaint of lack of power or anemic rate of climb
 

Bigshu

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I am trying to purchase an Ultra Cruser that is FAR 103. But to do this I am told that the 1/2 VW engine may be too heavy.
But the Predator 670 does not have enough HP to safely fly a 200-pound pilot. Does anyone have any real experience in the Ultra Cruser with either the Predator 670 or the 1/2 VW engine.
One of the questions I had for Matt while at Airventure was how the UC would do with the V-twin and me as the pilot (I'm linebacker sized, with weight to match). He pointed to a picture of the prototype test airframe with the V-twin mounted, flying, and told me that he was the pilot in the pic, and at the time weighed more than me. He was certain that I could both build it light enough for pt 103 compliance, and comfortably fly it safely. He did tell me that he wants to tweak it a little bit to make low fuel/heavy pilot have better balance. As it stands, it's at the rear of the envelope in that scenario.
 
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