Tyson

We are comparing a variety of apples to a variety of oranges. The old CPs (as well as owner's manuals) listed relative efficiency of a variety of FP propellers from different sources (most of which aren't around any longer). Suffice it to say: -CS holds no superiority in cruise vs a properly selected "cruise" FP propeller -FP generally affords the pilot the ability to exceed redline limits imposed on CS propellers (thus FP can utilize a higher horsepower, if the FP pitch is set accordingly). Along this line, top speed could be faster with the FP -at 5kts, a FP propeller set for efficient cruise at 170kts is simply not going to be anywhere near as efficient at producing thrust as a CS propeller set to fine pitch. How much less efficient, I don't know, but significant. Waiter has written on this previously with some apples-apples discussion. Now, practically, who cares. If one limits operation to longer runways, there is no compelling cruise or range consideration that favors using a CS over FP.

I don't know if you're having a bad day Wayne, but obviously thrust moves airplanes, not horsepower. There's that pesky "propeller efficiency" thing to deal with. IMO the only good reason to go CS in a pusher canard would be to improve low airspeed thrust efficiency (i.e. get off the ground sooner). For some people this is a very valid concern, but not really necessary for most. Do you really mean to suggest that your take-off role would be reduced by only ~7% if you had a CS propeller installed?

For those interested in "conventional" type bagging with a regular vacuum pump... Look into the type of system that ACP sells...specifically the nylon vacuum bag tubes with "quick lock" seals. ACP sells bags that are 18" or 36" across. Essentially you create your layup as usual, apply a breather, batting, then slip into the bag. Apply the quick locks to each end of the bag. The quick locks don't leak. Attach the vacuum to the adapter nipple and turn on the vac. The bag is re-usable a few times (depending on how you take care of it). -This system doesn't leak, except maybe around the adapter into the bag (the nipple that goes through the bag). Easy enough to locate and deal with. -This system is easy to do on small flat pieces, adds negligible time, and just a little bit of consumables. -This system is impractical except for those hell bent on weight savings. And if so inclined, seems easier/less messy/more reliable than low vac.

Not exactly hard data, but a simple discussion on this topic: http://www.newton.dep.anl.gov/askasci/eng99/eng99494.htm Another discussion on the topic. Of note is the issue of heat 'absorption' issues as related to engine compartment objects as they relate to paint color etc. Perhaps this is why white is a common engine mount color: http://www.sacskyranch.com/paint.htm

I picked up this project locally but unfortunately will never get time to complete it. Included is a tub with the main gear mounted, wheels/axles/brakes, nose gear retract, canard hardware and jig, glass role for the canard caps, epoxy pump, hotwire cutter, nose gear leg. Speed brake is installed and hinged. Some misc Brock hardware included. Also will throw in an old Varieze canopy in frame (Jiran?) if interested. I'm moving soon and don't want to have to move it. Price is $1500 for all, not interested in any offers to buy individual components (plans etc). Great workmanship and a great price. If I have to move it price will go up later. Located 30 minutes south of SLC, UT. PM or respond here with questions. Attached is the only picture I have available for the next week or so.

On a related note, for those interested, take note of the clothing you wear while flying. What you're wearing (or not wearing) in a firery accident may significantly alter your outcome (i.e. life/death). Note that in wintertime we frequently bundle-up in torch material and summer leave our skin exposed with no protection. Generally natural fabrics are most practical and synthetics are to be avoided.

Priceless pearls from NeoTom: "Once the chain departs the cockpit over the pilot's head, you won't need any "wind speed", the prop will come and get it with the sure certainty of the moron-vote finding the Obama Box in November; It WILL happen." If your appreciation of basic physics is any indication of your ability as a social scientist... Rutan suggested in the first place to just open the canopy and jump over the side. Look it up in the Canard Pusher. Per Rutan (and Newton) the aerodynamic loads (i.e. that drag force that would 'slow you down and drag you into the prop') don't really become an issue until you get up to 250mph. Then again what does Rutan know about "sub-sonic" aerodynamics.

To test/disprove Newton's second law.

A picture would help.

To read previous discussions on this and most any other idea you can come up with, check: http://www.maddyhome.com/cozysrch/

This is about $100,000 too much, but good luck to you.

Depends on what you mean by "gentle." Research Ilan Reich's incident of plopping his Cirrus down in the Hudson. The landing gear does little to absorb energy when hitting water. A 26 fpm drop on my rear end with an inch or so of miracle foam to cushion the blow isn't what I'd consider to be a "gentle belly flop."

There is one pilot of an Ez (a Varieze I believe) who bailed out after thinking that the plane was hit (shot) by ground fire. The author recounting the incident stated that the pilot was a veteran and was presumably of sound mind, even though the circumstances were suspect. He lived, I don't know if the prop was turning. I thought I read about this in the CPs, but I can't find the reference. Maybe someone else can substantiate where this story came from.

A quote from the mooneypilots.com site article about the Mooney 20E (you can read the full article on the site for free): "I would like to make a comment from a technical standpoint about the ram air system on the E model. Mooney's marketing department made a big deal about the ram air system back in the '60's--a "poor man's turbocharger" and all that stuff. Talked about how it was a stroke of design genius to offer this primary induction system bypass to give added engine power and better airplane performance when flying in clean air. Bull. There is no way a properly designed primary induction air system should have a 1" hg manifold pressure drop across the filter. I think the ram air system on the E model was simply a bandaid [my emphasis] for a poorly designed primary (filtered) system. If Mooney's powerplant engineers had designed the primary induction air system properly in the first place, they wouldn't have had to incorporate this "ram air" idea. It's bad engineering to require the pilot to open an induction air bypass to get the engine performance he deserves in the first place. And unfiltered air is not good for the engine." From a simple-person's point of view, I do not see many super-fast/efficient planes with ram scoops hanging in the breeze. Thus it might be reasonable to conclude that the drag associated with scoops outweighs any benefit.

This may have come out clear as mud, but here it goes: With the c-jig, you could do this by making the initial drill-through hole (in the jig) 1/4". Then remove the center of the jig (with sufficient depth to lap over the NG30 outer surfaces, about 3.75" or so). Then open up one end of the c-jig to 5/16". Place the jig over the NG30s. Place a 1/4 bolt through the jig and either NG30 (i.e. the side that you are not currently opening up). At this point, the 5/16" opening of the jig should be centered over the 1/4" holes in your NG30s (assuming! that your current 1/4" holes are aligned). After drilling out the first side, remove the jig and open the other end of the "C" to 5/16". Replace the jig over the NG30s, bolt the first NG30 to the jig with a 5/16" bolt, then open up the second NG30 to 5/16". The idea here is to create a jig to open up the 1/4" holes to 5/16" without making out-of-round holes while keeping things as square as they currently are. It self-aligns/centers using the current holes.

I don't know if it would be possible to build such a jig that would fit in tight quarters, but check out the picture of this jig that is used to drill holes through the KR-2 wing spar (to align the bolts in the wing attach fittings): http://www.kr-2s.com/images/pass_600.jpg A few step process would be involved to open the holes but I think it is doable if so inclined.

The fiberglass in a Corvette is a crumple zone as compared to a Buick with steel running all the way up front. Recall that in RAF's early building videotape Burt demonstrates the strength of the composite structure vs an aluminum structure. Essentially what could be described as a tail structure was built where one half was epoxy/glass, the other was standard aluminum/rivets. Burt and Mike simultaneously jump on each side of the structure that is supported at the tips. Mike, who weighs less, crumples and fails his aluminum side whereas the heavier Burt doesn't seem to cause any damage to the fiberglass composite side. Whereas the aluminum crumples/fails, the composite leaves Burt's bones/joints/disks to accept the majority of the deceleration. I believe both Burt and Mike proceed to both jump on the composite side without failing it. What this means in the real world is again nebulous. Different crash scenarios might favor either composite or aluminum or even wood. In the real world I doubt there are instances where one looks at a crashed plane with fatalities saying "they would have made it if this thing was built from composites" (but probably lots of instances where they would have made it if they didn't hit so damned fast). Generally speaking, composite airframes seem more rebuildable after crashes whereas aluminum structures are a write-off (too many creases/bends here and there). It takes energy to deform the structure...energy I'd rather have the structure soaking up instead of my innards. YMMV At the end of the day it's energy that kills. Your brain sloshes around inside your skull. Your organs slosh around getting bruised and tug on arteries not up to the task. You want to do anything you can do to minimize these forces. Having a superlatively strong airframe does not help you here.

Theory vs reality. While composite materials might be stronger ounce per ounce, composite planes generally weigh as much as planes made from other materials. A LongEz at 1400 pounds carries as much energy into a crash as a RV-4 at the same landing speed. But of course the RV-4 lands slower. On kinetic energy, recall that it equals 1/2 * m * v^2. So some simple calcs finds that the KE (in relative units) = : LongEz 1400 pounds 65 knots: 2,520,500 RV-4 1400 pounds 50 knots: 1,750,000 Cozy IV 2050 pounds 70 knots: 5,022,500 RV-10 2700 pounds 58 knots: 4,541,400 Recall that speed doesn't kill, it's the sudden stop. So you want the airframe to be able to dissipate energy. Maybe the designer has helped you out here. Maybe you need to dig a wingtip on touchdown. At any rate, speed is squared in the above equation and as such marginal changes in mass (structural weight) are much less important from a KE standpoint. And any talk about which experimental airframe tears apart more favorably is entirely nebulous.

As there has been some discussion on low-orbit flight, I thought I'd put this link I found on oxygen up for anyone interested. http://www.dg-flugzeugbau.de/sauerstoff-e.html

Jim, I'm disappointed that Wicks couldn't afford to buy the Cozy rights and that you could. I'm disappointed that you're taking the time to "notify" all builders that Wicks is no longer an approved supplier. I'm disappointed with AS&S for the numerous problems I've had with orders from AS&S. I'm disappointed with AS&S for all the problems many (most?) other homebuilders have had with AS&S over the years. I'm sorry that your buying power price-matching scheme will sooner or later rub out most of the competition. I'm sorry that people have to check your catalog, your online price, Trade-a-Plane, and every advertisement you have to make sure they're getting the lowest price you are currently selling products for. Knowing AS&S, you've probably already contacted Nat to apologize that his first royalties check has been back-ordered, and you'll get it out ASAP. Then you'll send it out late to the wrong address. Then you'll send it to him, but will short it and personally apologize. Then two months later the first check will be paid in full. I'm not disappointed when I spend 5% more to deal with stand-up people and receive quality service when ordering from Wicks.

1) "Speed of sound" = 38.967854*sqrt(T+273.15) where T is the OAT in celsius. TAS is true airspeed in knots. At 48,000 T usually = -56 celcius Plugged and chugged CS = 574 knots at 48,000 2) IAS of 200 knots at 48,000 ~ TAS of 392 knots. 3) Mach Number (M) = TAS/CS 392 knots (plane) / 574 (sound) = Mach .68 Above text copied from the web. The calculators I used for these numbers are (formulas are crude): http://www.csgnetwork.com/tasinfocalc.html http://www.csgnetwork.com/machonecalc.html What do you mean "how we should" define the speed of sound? As for the flutter issue, check my message under Marc's newer speed thread.

Hopefully adding to the discussion, For a discussion of IAS vs CAS vs flutter etc, do a google "groups" search using keywords "canard performance flutter equivalent". Read the post by highflyer dated Jan 4, 1999. Among other things, note the issue of localized transonic shockwaves, as Marc has pointed out. Another unhappy point for the future test pilots. During flight testing for flutter at 320 knots, a catastrophic failure may result in a non-survivable, or at least incapacitating g forces. Wearing a chute may not be of value if one isn't awake to use it. I think the first BD-10 loss was at 380 knots when the tail let go and the pilot's neck snapped. BTW, I'm pretty sure Jim's engine was nowhere near stock (ie it wasn't a 135hp engine).

I basically agree with all of your sentiments, particularly about the airline ticket. It should be noted that flutter is not simply related to IAS (ie you can't take a Cozy to 48,000 feet with a turbine and safely cruise at 390 knots with an IAS of 200). This mach .67 cruise would indeed be experimental. It is a common misunderstanding that flutter speed (presumed VNE limiting variable) does not change with altitude. It is true that other canards do fly at higher than 200 indicated. The Berkut has a carbon canard (and wings), though I believe the E-racer has essentially a LongEz canard (not sure about this). Regarding flutter, I would Assume that the carbon structure would be less flutter-prone. I mentioned the idea of building another, faster design as it seems a bit if a compromise to build a Cozy into something it isn't. If you look at the KR community, you see people spending thousands of hours and tens of thousands of dollars trying to make a KR-2 into a Glasair (without coming close, except in terms of expenses).

Why build a Cozy if you want to go 250-300mph? Canards are great for efficiency couple with a stall proof design. The only logical reason to keep the Cozy planform at 275mph is because you want a stall-proof design (because you've thrown efficiency out the window). 1) The plane was not designed or tested for these speeds. 2) Other designs are available in that speed range. 3) Max efficiency is well below 200 knots in the Cozy. 4) Any engine used to get 250mph will go even farther from max efficiency. 5) The average GA cross-country trip is short enough that the 30 knot difference in top speed gets you there minutes earlier, not hours. At a higher cost. 6) For long-distance traveling, efficiency usually means less stops and an earlier arrival. On a long cross-country you will be fueling your overweight gas guzzler while your efficiency minded hangar partner cruises overhead. Good thing you had a stall-proof design safety factor, because you had to make use of it twice when low and slow landing and taking off again. Jim has it dead-on correct: "The more I do the math, the more attractive simple and inexpensive gets." Change the word "I" to "you" and write the sentence in big letters on the wall in your building area.

Just to clarify, there is no problem of elevator flutter. There have been problems with people not following instructions (plans and/or operating manual) which have resulted in problems of flutter. This is not a design problem.