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?
10/23 Raptor Video
- Thread starter Volzalum
- Start date
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Wanttaja
Well-Known Member
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
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
Well-Known Member
No, it's not just you. The fanboi comments seem to have dropped into the minority.
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.
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.
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.
So a welding shop made the parts?
rv6ejguy
Well-Known Member
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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Failed turbo and possible fire.... Sounds worse than ECU failure.
I guess that's all I need to know, for now. Thanks.
I guess that's all I need to know, for now. Thanks.
flywheel1935
Well-Known Member
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?
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).
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).
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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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
Well-Known Member
.045? I've seen .063 manifolds crack often. I developed a taste for Sch10 or thereabouts.
But the canard is rigidly fixed with the wing. They work together, he can't change the canard incidence relative to the wing.
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.
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.
