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Raptor Composite Aircraft

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flywheel1935

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Jeff Kerlo as Director of Engineering, Simple Question, Did he jump or was he pushed ????
And still can find no answer ref the design of the PRU, and who considered it a viable option,
somebody obviously sat down with pen and paper/cad and thought engine in rubber mounts and PRU rigid to the engine support, FFS.
 

BBerson

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The Orion was/is slightly larger than the Raptor and about 10 % larger than the Velocity XL. The prototype with a twin turbo Cont. I0-550 weighed in at 2265 lbs empty and flew beautifully with better characteristics than the often cloned Rutan format.
Thanks Jeff, good info. I should have said involved instead of designed. I assumed you had the most experience. So hard to imagine how this overweight happened.
Is the Raptor basic airframe significantly overweight? And where?
Or could it weigh close to 2265 lbs empty if fitted with a Cont. engine and no pressurization?
 
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canardlover

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Canton, Ga USA
Here are a couple pages from"Jane's All the Worlds Aircraft" describing the Orion with specs, mostly all accurate. I was interviewed at Osh by Paul Jackson , the editor. The aircraft started out being named by me Orion back in 2002, and went through three ill fated partnerships( money guys), it was also renamed"Phoenix" by myself during second partnership after being rescued ( with the help of the FBI) from the first partnership. And returned back to Orion in third partnership.🤪🤪🤪🤪. They published info on a couple of my other designs as you can see. The orange canard display model pictured is/was a design of a friend, Wayne Lanza, that we intended to co-develop at the time.

)
 

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BoKu

Pundit
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The aileron pulley brackets are entirely emblematic of the Raptor project. Peter designed them in CAD (wohoo!), and just plonked them down onto the inner surface of the fuselage skin with no consideration for local stiffness. It's carbon and carbon has magic stiffness, right? The Wasabi guys found that you could hold the ailerons on one stop and wind the control stick onto the opposite stop with only moderate pressure. But, hey, Peter was OK with it.
 

pictsidhe

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Jeff Kerlo as Director of Engineering, Simple Question, Did he jump or was he pushed ????
And still can find no answer ref the design of the PRU, and who considered it a viable option,
somebody obviously sat down with pen and paper/cad and thought engine in rubber mounts and PRU rigid to the engine support, FFS.
Peter designed the PSRU. In CAD, so how could it not be perfect?

Peter delegated stuff he knew he didn't know how to do to people with an actual clue. The problem is that he doesn't know the extent of just what needed delegating. Spar design? Beyond him, hire an engineer. Control design, how hard can that be? Well, it uses much the same engineering techniques to properly design as a spar. It's also something that if you get it wrong, can also result in a sudden lack of wings...

To compound the problem, he has ignored sound advice from actual experts on the parts he has done an abysmal design job on. So far, they have been way, way better at assessing faults than he has. Yet, he continues to pooh-pooh any and all notifications of potential problems. After being wrong about crucial things so many times, why does he keep on ignoring experts?

Now, he seems to have decided that actual test pilots are making unnecessary demands before flying his whale.
 

rbarnes

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Texas
Only 325lbs, or 68%, over his predicted engine weight. Did he get a bargain pile of 4130 plate?
Go back and rewatch him putting that thing together. 2 turbos and all the interconnecting pipe, intercoolers, fuel warmer heat exchanger, a/c, redrive, the mount.

The engine mount/redrive frame alone looks like it weighs 100lbs.

 

Volzalum

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Well he has a new video up. He says he’s going to fly some other planes to get familiar with the pattern and location and then get it around the pattern. Wonder if any of the other planes are a canard.
 

pictsidhe

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I saw two offers from Velocity in his last hop video to give him canard training. I have a horrible feeling that his ego won't fit in a Velocity.
 

Volzalum

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Someone on the POA forums pointed out that where PM thinks his airspeed and groundspeed are equalizing once airborne, it looks more closely like the airspeed comes down to closer to the groundspeed when the power is reduced. Probably indicated there is some vacuum caused by the engine that is affecting the static (i.e., making the static appear lower).
 

pictsidhe

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Someone on the POA forums pointed out that where PM thinks his airspeed and groundspeed are equalizing once airborne, it looks more closely like the airspeed comes down to closer to the groundspeed when the power is reduced. Probably indicated there is some vacuum caused by the engine that is affecting the static (i.e., making the static appear lower).
The static is upstream of the engine. Why he put a pitot-static out on the wing, but didn't plumb up the static is yet another curious feature.
 

Volzalum

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The static is upstream of the engine. Why he put a pitot-static out on the wing, but didn't plumb up the static is yet another curious feature.
That’s my point. The engine/prop/PSRU may be pulling air from the location of the current static port. It’s not difficult to suck from upstream and get it to a lower pressure than ambient. Especially if he’s done a better job of preventing air into the location.
 

jet guy

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Maybe worth creating a small table - hp one variable (lets say 200,250,300,350,even 400) and best ROC speed the other variable (90/100/110)

Assuming we get a flight sometime soon we then then fill in some of the missing information quickly (what is the actual hp)

That's a good idea.

Raptor Climb 90.jpg

Raptor Climb 100.jpg

Raptor Climb 110.jpg

So we see that of course at the lower climb speed the rate of climb increases, since we have lower drag at the lower speed. But is 90 knots really feasible as a climb speed for this airplane, considering that he rotates at 90 at a fairly light weight?

I'm including here the Climb Calculator I worked up to get these numbers. As mentioned previously, you have to have some idea of the airplane's drag in order to try to estimate its climb performance...since the amount of excess power available is going to depend on how much power is required to overcome the drag in the first place.

In this calculator, I continued with the SR22 as the known quantity. We use the Cdo that we extracted previously with the drag calculator, as well as the Oswald number, which is a key part of the induced drag. So since we have established these key parameters already, the only thing we don't know is the prop efficiency at our climb speed.

Knowing that the rate of climb is 1,304 fpm at SL ISA, we can simply iterate the prop efficiency until our calculated rate of climb matches the book number. It turns out to be 0.615. You can do this with your Saratoga or any other airplane for which you have solid data.

I've included below that the same computation for the Raptor climb rate. Here we estimated the Cdo at 0.03 and the Oswald number at 0.8. Both of those may in fact be a little generous.

The numbers really speak for themselves. Carrying that much weight, this airplane does in fact need about 350 hp to even see 1,100 fpm at 100 knot climb speed. And that's still less than the Cirrus.
 

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BBerson

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He did fly about 2000 feet with reduced power as I suggested. So that was good. But the final cockpit view ahead didn't look so great. Looked like a yaw oscillation side to side. I would kick some rudder and see what happens. I don't think he really tested yaw or roll much.
 

BBerson

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Also, if you are trying to clear the trees you want best angle of climb speed, not best rate of climb speed.
 
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