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Voidhawk9

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Everything posted by Voidhawk9

  1. 1,000lbs overweight, a PSRU that's failed twice on the ground with only around 20hrs run time, and a repeatedly modified elevator of dubious effectiveness. Yeah, even his test pilot won't touch it. I really wish it didn't have serious problems, but I don't see any light at the end of the tunnel for the Raptor.
  2. Under 500kg MTOW. Very light. The mid-span fence on the winglet is interesting.
  3. This section of the forum is for rants, and that is a good one. It is a topic I am watching carefully myself and trying to prepare (somewhat...) accordingly. One can readily learn from history that all empires fall. Typically they get over-extended and bankrupt themselves. Sounds familiar. Here in NZ things are not quite as dire financially, but the socialists are in power now and doing their best to tear the place down. Still, it is well known that a number of mega-rich persons have bug-out estates over here. Still planning where I am going to build mine!
  4. How about a folding tray table for your passenger's meals? 😉
  5. NACAs are great for things where sometimes you want the air to skip over the top, like for an air vent that may be closed sometimes. Not so great for pressure recovery - as stated in the original paper describing the inlet. North American tried to use huge NACA scoops to feed a jet engine (YF-93), which did not work very well, and after tweaking the NACAs a lot, just replaced them with ram scoops. Some guys have made them work, and obviously a lot of canards use them, but they do seem very sensitive to details to cool properly. Not sure how much the rounded cowl vs open cooling outlet have in common for airflow there. Though, I'd expect that the cooling air -having been twisted through at least 180deg and forced around the engine- doesn't have a lot of energy relative to the free-stream and so will stagnate and burble around readily. Having the outlet not too close to the prop seems to help too, perhaps the pressure wave or the blocking presence of the prop blocks the cooling flow somewhat. People have reported improved cooling once they cut the cowl back a bit. Apparently the prop does not suck the air out here - that section at the root of the prop is thick and relatively inefficient anyway. Still lots of potential for improvement in canard aft ends, IMHO. Exactly what that looks like is another question!
  6. "Speed with Economy" is a great read, very inspirational. Right up there with Mike Arnold's work.
  7. Lower winglets should help. Making the pod pylons longer chord-wise probably would too, as it adds even more vertical area aft. It would be interesting to see if wing fences helped noticeably. It all adds weight and wetted area though. Ultimately the best solution would be cut off the nose and re-do it. Plenty of nice examples out there with nicer than plans shapes without being needle-nosed like this. Looks like a nice example besides, as far as one can tell from small photos anyway. Clearly a lot of thought has gone into it, even if I don't necessarily agree with all the conclusions arrived at.
  8. Or add VGs or turb tape to the existing one. Much easier!
  9. 1-Agreed! 2-Seems to be, yes. Though Longs seem to have their share of NG failures too. 3-GA is much smaller and more expensive here, there's not really a GA hub. Most 'busy' GA only airports are grass.
  10. Debris into the prop is much less of an issue with wide-set gear like that and a deflector on the nose-wheel. Use of unpaved runways is much more common outside the USA, even with canard pushers. There's one up north of here that even Lears have been known to use. A bigger issue is likely the nose gear. Probably OK with the Long, but barely adequate on a Cozy, and a bit of a gamble in a Cozy on unpaved surfaces.
  11. No fault found, no reason for the engine failure. I was a passenger in an Aztec that had an unexplained failure in one of its Lycomings too, leading to a forced landing on a parallel runway as it occurred at low level and below redline speed. Started right up afterwards. No fault found.
  12. Thanks for the update. Sorry that it hasn't gone too well today. But we are all learning here! 🙃
  13. But where would be the fun in that? OK, this is a potentially very good deal. Once my airplane is done (on Tuesday) picking up an airframe like this and upgrading it could be a fun next project!
  14. Two contributing factors, I think. First, we were a pretty good source of military personnel in WW2, training thousands of pilots (and other kinds of soldiers of course) and sending them off to Europe (mostly). Second, being a rugged country of low population density, using aircraft made a lot of sense for travel and other applications in decades past. Both still apply in a broad sense, though the government is making things more difficult and expensive over time.
  15. Depends on the CS unit in question. If something like an MT, I would be very much inclined to agree with you, Kent! I should call into the Sprint Aero facility sometime and see what's what. In fact, I think I walked right by it 2 weeks ago while hunting for interesting aircraft at NZRT (found a V8 powered Mk26 Spitfire - boy did that sound great taking off!).
  16. These look interesting. Not sure of the price, but apparently they are light and effective? But if you're only going to operate from good sized runways and don't mind trading off a bit of climb rate, the fixed pitch is probably the way to go. On the other hand, if you want to be able to utilize the engine's full potential across a wide range of speed and altitude, fixed pitch cannot deliver that. I'd been doing some simulations with my Cozy, and using a fixed-pitch setup that works at acceptable RPM when cruising high and (really) fast, take-off and climb performance is quite poor for the installed power, and the pitch is very coarse. With a constant speed prop, the cruise is the same, but the acceleration and climb is stunning! For a 100hp Tri-Q, the difference is probably much less though.
  17. Hi Rafael, welcome. I too was very interested in a 13B powerplant. I researched and learned as much as I could for several years. Theoretically, it should be ideally suited, in reality, it seems few achieve acceptable performance. And, it's an old design that, while still popular, maybe be more difficult to support in the future. Plus, loud and thirsty. I'm still interested in using an auto-conversion when the time comes, but it will be reciprocating, require minimal modification (besides the necessary PSRU and ECU of course, but ZERO changes to the internals), and have a good history of prior use in aircraft (not necessarily canards, which are an increasingly small part of the homebuilt fleet). Your experience and education may save you time in airframe construction. You'll probably soak that up and more with an auto conversion, though, especially a complicated one like a rotary. But please share and discuss your progress, ideas, etc. as you go for the benefit (and entertainment!) of other users here! 😉 John Slade may have before his passing, but then again he never resolved his cooling issues, probably due to the suboptimal cooling design he was convinced to use. It seems a lot of Lycoming powered canards live with cooling issues as well, though!
  18. Photos of the spar construction to date. Click for larger images. Foam parts prepped and being installed. Glass and peel ply cut and labelled ready to easily find and apply. A few extra pieces of peel- ply that I didn't need in the end, but easier to have prepped and ready in advance in the event that I do. Glass in the process of being wet-out. Bulkheads in, hardpoints next. Weight on the wing attach hardpoints. As you can see, I didn't install the end caps bulkheads yet. As I will be installing Infinity retracts (I don't own a set yet - budget limited!), I will need access into this area when installing the fixed parts of the gear, so the end bulkheads will go on once that is done. This also made it very easy to weigh down the outboard hardpoints, as I could just clamp down on them. The inboard hardpoints had approx 5lb on each per plans. 1l peanut butter jars filled with water =1kg each plus the weight of the stand= approx 5lb. After cure, but before trimming. It came out nicely. Thanks, Jon - yes I have a lot of big projects going on! Hopefully, the Cozy won't take quite as long to grow up and leave home as some of the others. 😅
  19. Another slow couple of months for progress. I had the foam all done and joined and everything ready for the spar interior layups. But since I needed most of a day to get all that done, I had to hold there, as I was waiting for a very short-notice report that my wife was about to have a baby; "can you wait till four, darling, while I finish these layups that must be done together?" Family first! Baby arrived a month ago (boy #4!), and I've since been keeping myself available for my very capable but tired wife who now has 4 young guys to take care of. Finally, she told me to go ahead and restart plane days. So today I got the interior layups done. I took several photos, but the camera is out in the workshop and I don't feel like standing up again just yet. Will post some later. 🤓
  20. Plenty of room to the sides, but vertically a bit tight, yes. Custom cowl will be required - but if you are installing something other than an O-360 already, that should not be a big problem for you! It does appear to be a Ballistics redrive, which I like, well proven and numerous, but quite a low offset from the crank, so the engine has to be up fairly high. You are right about ballast. Putting batteries in the nose will help. I'm going to install hydraulic retracts, so the hydraulic pump can go up front, that should do the trick nicely.
  21. I get the impression from the Titan guys (I hang around the Titan Air Corps forum to feed on engine discussion) that few are installing Suzukis anymore. Ditto on the Hondas - I looked into that one a bit myself. The LS3 is not much heavier, and puts out way more power at more conservative RPMs, whereas the Honda is working really hard to hit its numbers. You might enjoy this video:
  22. That's a pretty rapid erosion. Freezing rain or hail?!
  23. Maybe Titan or Supermarine would sell you one of their LS V8 FWF setups. Heavier than the other options, but similar to a -540, which has been done several times. And WAAAAY better fuel economy than a rotary. Plus, they are common, still in production, reliable, multiple PSRU options, and relatively affordable. They appear to be in use on various types with great success, with little or no modification to the engine. 350-450hp at conservative RPMs.
  24. Another case of 'if it sounds too good to be true, then it probably is'. Anything more than a modest improvement over existing engines is probably marketing in an attempt to attract investors, nothing more. Still waiting on the Deltahawks to arrive as well! 🙄 In contrast, Aeromomentum is actually building and selling engines and gaining a very good reputation, I will continue watching their new engine developments with interest.
  25. That diesel is a 'dream' for sure. If I'm doing my numbers right, those sfc numbers are twice as good as the best high-efficiency diesels in use today - and I'm talking power generators and huge ship engines, which are much better again than their smaller counterparts!
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