# 10/23 Raptor Video

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#### BoKu

##### Pundit
HBA Supporter
Is it just me, or does it seem to anyone else that the general tone of the comments on the latest couple vids is a bit more critical and less fanboi-ish than usual?

#### Wanttaja

##### Well-Known Member
It's more of a mockup, I think. But can be considered a prototype if used for some testing according to this definition: Mockup - Wikipedia
In space terminology, it's what we call "Protoflight" . There are no ground test articles, so you use the first flight article for qualification testing. Lower test ranges than you'd do a normal ground-test item, but higher than you'd normally subject flight hardware to.

Ron Wanttaja

#### BBerson

##### Light Plane Philosopher
HBA Supporter
Actually, I didn't realize it till today in that what I do as a hobby now is build "mockups". Highly unconventional aircraft experiments that may or may not be completed to full flight stage. No intention to sell plans, somewhat like Peter S.

#### pictsidhe

##### Banned
Is it just me, or does it seem to anyone else that the general tone of the comments on the latest couple vids is a bit more critical and less fanboi-ish than usual?
No, it's not just you. The fanboi comments seem to have dropped into the minority.

#### rbarnes

##### Well-Known Member
Another great compound turbo video. Little hard to listen to his uh's and uhm's, but lots of good info

#### Speedboat100

##### Well-Known Member
I am not going to comment on this Raptor video again.

I was on a one week penalty and realized that I was barking the wrong tree...as Peter says his kite is 130 K...he means only the kit and its parts ( that are listed in his site ).

So actually this is very clever..as the 500 K plane with your own work can be made into that 130 k budget with your own input of course.

#### BBerson

##### Light Plane Philosopher
HBA Supporter
Another great compound turbo video. Little hard to listen to his uh's and uhm's, but lots of good info

Interesting video. Some tidbits I heard on the video: "two years experimenting", "pressure port for dyno", "only the best bellows will avoid disasters", "cast elbows not available till now", "no room under hood".... etc.

My takeaway is that a safe system is likely far beyond an individual unless a dedicated specialist with all the equipment. Andreas mentioned a team of 130, I think. A custom build could cost $10-$30k or something?
Do the Raptor videos show any turbo specialist or who built the Raptor turbo system?

#### rv6ejguy

##### Well-Known Member
There was no turbo specialist involved with the matching, selection of components or design. A compound, high altitude, aviation setup is not something for amateurs to tackle. It would be challenging enough for folks who have extensive hands on experience already.

#### BBerson

##### Light Plane Philosopher
HBA Supporter
So a welding shop made the parts?

#### rv6ejguy

##### Well-Known Member
So a welding shop made the parts?
Peter had an excellent welder close by to join the exhaust bits (Britt sp?). They were cut out and fitted by Peter and his crew if I recall. No problem to cut and fit tubing and flanges yourself, it's the selection of materials (only 321 or Inconel tubing should be used on aircraft), allowances for thermal expansion (either bellows or slip joints) support of the turbochargers (never hang them off light gauge tubing) and gauge of material (.045 minimum wall) that's important. A first time turbo system builder will know none of these things.

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#### BBerson

##### Light Plane Philosopher
HBA Supporter
Failed turbo and possible fire.... Sounds worse than ECU failure.
I guess that's all I need to know, for now. Thanks.

latest YT Video.

#### Kyle Boatright

##### Well-Known Member
HBA Supporter
latest YT Video.
At about the 6:00 minute mark, he comments that with a more loaded canard, the AOA will be lower.

That's completely backwards, right?

#### Voidhawk9

##### Well-Known Member
HBA Supporter
It looks like the gap between the wing and the back of the strake (where the wing extends along the back of the strake) is flexing open and closed a bit. Probably does that more in-flight?
Not sure if other canards do this much, haven't seen a video from this angle on another. Also, the mounting is a bit different here (two bolts inline here vs 3 bolts with outboard ones high and low on other canards).

#### BBerson

##### Light Plane Philosopher
HBA Supporter
That's completely backwards, right?
I think he is correct but not anywhere near 3° difference. Remove some load from the back wing and the back wing can fly at less AOA. With more load on the canard it will need to lift more with the elevator.

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#### Kyle Boatright

##### Well-Known Member
HBA Supporter
I think he is correct but not anywhere near 3° difference. Remove some load from the back wing and the back wing can fly at less AOA. With more load on the canard it will need to lift more with the elevator.
I was thinking he was talking about the canard. Which would need a higher AOA to carry more weight. He can achieve that through aircraft pitch attitude or by using the elevators to increase the effective AOA of the canard.

#### pictsidhe

##### Banned
Peter had an excellent welder close by to join the exhaust bits (Britt sp?). They were cut out and fitted by Peter and his crew if I recall. No problem to cut and fit tubing and flanges yourself, it's the selection of materials (only 321 or Inconnel tubing should be used on aircraft), allowances for thermal expansion (either bellows or slip joints) support of the turbochargers (never hang them off light gauge tubing) and gauge of material (.045 minimum wall) that's important. A first time turbo system builder will know none of these things.
.045? I've seen .063 manifolds crack often. I developed a taste for Sch10 or thereabouts.

#### BBerson

##### Light Plane Philosopher
HBA Supporter
I was thinking he was talking about the canard. Which would need a higher AOA to carry more weight. He can achieve that through aircraft pitch attitude or by using the elevators to increase the effective AOA of the canard.
But the canard is rigidly fixed with the wing. They work together, he can't change the canard incidence relative to the wing.

#### 231TC

##### Well-Known Member
Is it just me, or does it seem to anyone else that the general tone of the comments on the latest couple vids is a bit more critical and less fanboi-ish than usual?
I thought so, too...but they are back tonight! Maybe they're just the first to watch it and will be drowned out by other comments, or maybe it's just that there isn't much substance to comment on in this one.

#### Voidhawk9

##### Well-Known Member
HBA Supporter
But the canard is rigidly fixed with the wing. They work together, he can't change the canard incidence relative to the wing.
But the effective incidence increases with nose-up elevator. This increases the ift generated by the canard, reducing the lift required to be generated by the main wing, so slightly lowering the overall aircraft AoA.