Raptor Aircraft

No mention of the high speeds. Weren't sustained anyway. Maybe they were just bad data.
 
donjohnston said:
Over 100kts when crossing the threshold. Damn! :eek:
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It would be interesting to know the actual minimum speed it can fly. I can't imagine an engine out situation, screaming down into a forest, rocky field, whatever at 100 knots with just a bit of fiberglass between me and whatever obstacles are in the way. I just hope the 'chute works if that circumstance ever presents itself.
 
donjohnston said:
Over 100kts when crossing the threshold. Damn! :eek:
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Yep - looked closer to 110 than 100. Pretty damn fast for a light piston single.

Wonder when he’ll start looking at the airplane’s slower flight characteristics, stalls, etc.
 
WillFly4Food said:
Yep - looked closer to 110 than 100. Pretty damn fast for a light piston single.

Wonder when he’ll start looking at the airplane’s slower flight characteristics, stalls, etc.
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Hopefully with a parachute and/or caps and sufficient altitude.
 
WillFly4Food said:
Yep - looked closer to 110 than 100. Pretty damn fast for a light piston single.

Wonder when he’ll start looking at the airplane’s slower flight characteristics, stalls, etc.
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I don't know... The airspeed is totally useless because of his static port placement. I was looking at the GPS groundspeed. He said it was "very windy" so I'm guessing that means 5kts.
 
I don’t have the stomach to watch the videos and listen to that guy talk. Is he doing anything on these flights yet? I’ve heard he’s left the pattern a little, but nothing in the way of actual flight test.
 
Best-glide would be nice to know, just to be able to pick out the best spot in the forced landing diameter (pre-chute, or chute malfunction).

90-100 kts short final is Cirrus, A36, etc speeds, no?
 
455 Bravo Uniform said:
90-100 kts short final is Cirrus, A36, etc speeds, no?
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And that’s at max gross. Some Cirrus pilots do some mental math to decrease the speed on final when lighter - subtract x knots for each 100 lbs lighter than gross. I forget the exact formula right now, but someone here may recall it.
 
75 % power yielded a whopping 700 fpm average with only one person on board. An XL would have been over 1,500 fpm with that power setting. While in cruise he was averaging 135 kts GS. Don’t know what he had the power at for that but it was 12 gal/hr fuel flow. That same fuel flow in an XL would produce probably 160-170 KTAS. My 173 (IO-360) at cruise power (75%) provides a speed of around 158 KTAS and a fuel flow just over 10 gal/hr.

It’s way over weight. It’s underpowered. It’s pitot / static system is still a mess.
 
To his credit, he talked about options for static port placement. His conclusion was to keep fighting with the fence in front of the existing location. But he is actively thinking about that problem.
 
iamtheari said:
To his credit, he talked about options for static port placement. His conclusion was to keep fighting with the fence in front of the existing location. But he is actively thinking about that problem.
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Yeah, but he was tufting the side of the fuselage looking for a "stagnation point" for relocating the static ports. Interesting approach. ;-)
 
Well today I was allowed to reply to comments on his YT channel. He’ll probably shut them down again.
 
iamtheari said:
To his credit, he talked about options for static port placement. His conclusion was to keep fighting with the fence in front of the existing location. But he is actively thinking about that problem.
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In front???

I had the same issue (static port in a low pressure area). Someone suggested the dam in front or a "trip strip" about 1/2" in front but those made it worse. I aborted the takeoff when I gained 100' of altitude during the takeoff roll.

I fixed my static port with a dam behind the port.
 
I was thinking about the comments of well he’s at least trying or how many people have designed and built their own planes? Well, several and they never had problems like this. Peter is no Rutan, Maher, Neibauer or a Van Grunsven. He’s a whiz with CAD but he’s trying to sell snake oil. Sure, he’s worked hard but if there are no fruits from all of that labor, it doesn’t matter.

If we’re going to honor someone for simply designing and building an aircraft, I nominate this guy.

 
donjohnston said:
I don't know... The airspeed is totally useless because of his static port placement. I was looking at the GPS groundspeed. He said it was "very windy" so I'm guessing that means 5kts.
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Tower advised it was roaring at 10 kts. Throughout the flight the aircraft was in 50' altitude oscillations, regardless of heading. It seems to be wholly unstable in pitch.
 
In the process of watching the video.

I think he was pleased that his indicated altitude was pretty close to what his Garmin said. I assume he was referencing the GPS true altitude. But due to what are nearly always non-standard pressure and temperature lapse rates, one should never expect their indicated and true altitudes to coincide, and having them agree, or nearly so, says nothing about the accuracy of the indicated altitude.
 
donjohnston said:
In front???

I had the same issue (static port in a low pressure area). Someone suggested the dam in front or a "trip strip" about 1/2" in front but those made it worse. I aborted the takeoff when I gained 100' of altitude during the takeoff roll.

I fixed my static port with a dam behind the port.
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Maybe it was behind. I don’t remember. I just heard him in the latest video talking about the dam.
 
I'm not an aircraft engineer but it seems that the plane flies a lot better at higher speeds, around 120 kias or better. The moment he reduces speed below that, the oscillations start. Probably explains why he's coming in fast for landing.
 
FancyG said:
Hopefully with a parachute and/or caps and sufficient altitude.
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He's already said he doesn't plan to do stall testing on this prototype. He said that "he knows how canards stall and what speed it should stall at already so there's no need to test."
 
TFulwider said:
He's already said he doesn't plan to do stall testing on this prototype. He said that "he knows how canards stall and what speed it should stall at already so there's no need to test."
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Godbless, eh?
 
I don’t think he’ll have any adverse effects during the stall. Won’t depart controlled flight at least. He’ll get into pitch buck and be controllable the whole time. I do think his 65 kt stall prediction is a bit optimistic though. I think more like 70 with him on board and 75 at gross. While I liked his Fowler elevator idea, I don’t think it’ll sufficiently make up for the canard size and excess weight.
 
Looking at this vid, he had a headwind on downwind and a headwind when he turned final? Really, the winds aloft kept showing a headwind everywhere he turned. His pitot / static is jacked and it’s messing with his Garmin trying to calculate winds aloft. What’s really telling is at 16 gal/ hr fuel flow, I think he’s maybe getting 145 KTAS out of it.

I predict 400 lb payload, 1,000 fpm, 160 kt cruise (non FL), stall at 73, and will require 3,500 ft min runways. But it’s going out to Cali for production so it’s all good.

 
Almost an hour yesterday too. New altitude record today, still shy of 5000. And immediately followed by descent to landing. I wonder how high the temps got.
 
The last video definitely looks smoother than the one before it.
 
16 minute flight today. Not a great sign, but anybody's guess why it was so short. Landed safely at least.
 
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