Jim Sower

Hmmmm! I tried the url on Explorer 6.0 and got the same result. Is there possibly something in my setup that might cause all the images to come out little boxes with 'x' inside? I really REALLY need for this thing to work.

Marc, I'm really glad we're back on track again :-)) <...I am familiar with Vn diagrams, and they are available for GA aircraft...> I didn't mean to sound like I was talkin' down to you about Vn. I (mis)interpreted a couple of things you said to indicate you weren't too familiar. Mea Culpa. <...I'm not sure where that 6G comes from...> I thought that was what EZs/Cozys were stressed for, and used it as basis for Vn discussion. <...Since the Va of the COZY is about 140 mph (IIRC), I've got to assume that Nat picked the 3.8 G from the normal category of certification to get his Va...> Agreed. I would hazard a guess that FAA requires that spam cans withstand 4G to be certified as normal category, and he just went with that. If Va was 180 mph, then 6 G would be the limit...> Exactly. In that event, our Vn diagram would rise more or less parabolically from min speed to 180 mph/6G, from there horizontally to 220 mph or whatever is Vne, and drop vertically back to the x-axis. Am I safe in assuming that Nat's Va is pretty much what I'm referring to as "maneuvering speed"? - the highest speed at which you cannot overstress the airplane - and (not incidentally) min turn radius? <...Bingo - pretty good guess :-) - or did you calculate that?...> It was a sWAG (de)emphasis mine. <...John T. Lowry's "Performance of Light Aircraft", has some excellent explanations and graphs of maneuvering performance of GA aircraft taking power and altitude into consideration...> I will look for it. Hey - it just this minute occured to me that 140 mph might well be the speed at which you can make -3G (what with upside down airfoils and all). That would make it your best T-storm penetration speed since you don't know how the gusts/shear are comin' at you. That makes sense to me, and doesn't clash with the 6G Vn diagram. :-) <...Better that than violent disagreement :-)...> True enough. However, here in my dotage I have'nt the energy to support violence upon the good guys. I need to husband my resources so as to better deal with the assholes of the world. In future interaction with you, my friend, I will endeavor to be less assertive and righteous. After all, right here recently, we've been in two or three pretty elaborate pissin' contests - only to discover, when the smoke cleared and the dust settled, that we'd all along been completely agreed on maybe 90% of the issues of any significance. Why do we do this to ourselves? I'll try hard to tread more lightly - but don't think for a minute you can slip some bullshit by me!

There has been some discussion in the Rotary list on spraying water on a radiator. I think it would work best if you could atomize it pretty well, and spray the mist over a wider area. The heat of vaporization would suck SCADS of heat out of the radiator flues, just as was you experience in Africa. Water injection has always interested me. I tried for a short while to water inject a Pontiac V8 around 30 years ago. I figured that when the water boiled in the combustion process it would expand and add lots of power. I further thought that it would quench the flame some and reduce Nitrous Oxide emissions. Wasn't aware of any side effects, but I speculated that the water boiling too quickly might cause something akin to detonation. Didn't have any money or sophisticated tools so I couldn't get a proper mixture (like about 1/4 to 1/2 as much water as gas) metered into the manifold and abandoned the project. I seem to recall that it was water injection on takeoff that allowed B-29s to operate out of Iwo Jima and make it all the way to Japan. Of course they were in a position to change engines after 25 hrs.

Jon, I agree with Dust and No4 that posts in the Coffee House, etc. that belong somewhere else be moved there and an appropriate forwarding button left in the old location. Perhaps a review of some of the more significant threads (whatever that might mean) would suggest a few new categories and/or subcategories. I went to the new site and got nothing useful. No links that went anyplace, and a number of those little things in the upper left corner that mean there's supposed to be an image here but it isnt. What was it supposed to look like? I have Netscape 4.77

Marc, I don't think we're quite on the same page (but almost - with mainly jargon and/or semantics getting in the way). Let's set up some parameters we can agree on: 1. SL, Std day - so we don't get into IAS/TAS issues. 2. Max Turn - pull to the onset of stall. Assume that max turn occurs at a particular AoA which is right where the Cl/Alpha curve breaks, where flow begins to detach and cal it "light" or "onset of" buffet (stall). 3. Sufficient Power to maintain a level turn at the G/AoA and airspeed we're discussing. 4. Any turn requires some G - 1 deg of bank offsets the lift curve and level flight will require 1.0001 G or something - you get my drift. OK. That said: A. Minimum airspeed, strictly speaking, occurs at the AoA we described above as our limit. Therefore there is only EXACTLY 1.0000G available, and it takes 1.00001 to turn at all so you can't turn and turn radius in infinite. B. Increase airapeed just a tad from minimum, and you have, say, 10' bank available before you get to your "Critical AoA" and you can turn. IIRC the relationship between bank angle (BA) and G to maintain a level turn is something like G = 1/cos(BA). 60' bank will buy you a 2G level turn. C. We are operating at the single AoA defined in (2) abve, so Cl is constant, Wing Area (S) is constant, q=kV^2 so Lift=KV^2. Double V and you quadruple Lift (so you're pulling 4G). <... your minumum radius turn (level), as shown by the equation above, will occur at the MINIMUM speed with the maximum acceleration ...> I'm not sure, but I think you're describing the Max Turn I described above but articulating it a little differently. <...I guarantee you that in a canard aircraft (or any aircraft, for that matter, that you're willing to fly at stall speed)...> YES!!! If you're not willing to fly at stall speed, you don't get to do a max turn because it only happens at stall speed. flying at the maximum bank angle, stalled, with the stick all the way back, will get you the minimum turn radius...> YES AGAIN!! I believe that's what I've been arguing all along (except I'm using the onset of buffet rather than "full stall" as the max practical AoA). The max bank angle is the arccos(?) of G. 1G supports zero bank angle, infinite turn radius. 90' bank requires infinite G to remain level (but buys ou infinitessimal turn radius), so somewhere between 89.9' and 90' bank, you "...flew up your own ass...":D <...It is obvious from looking at these graphs that flying right at stall at bank angles of 60 degrees or above AT THE MINIMUM POSSIBLE SPEED) will get you the minimum radii. He discusses the power needs as well...> EXACTLY!! Well, sort of. 60' bank, level, at 1.414 * wings level stall speed will buy you a 2G turn at buffet as I described above, and a 2G turn ..... <...This makes no sense. AOA determines G loading...> YES!!! <... Instantaneously, you can pull whatever G loading the elevator authority will allow, and it will last for however long the power available will let it...> NO!! You can pull whatever G loading the pitch authority AND AIRSPEED will allow. At or below "maneuvering speed" you will hit "high speed stall" (which we have defined above as where a "max turn" happens), at the G load corresponding to your airspeed, and THAT will determine your load factor and turn radius. Ever look at a Vn diagram? I wouldn't be surprised if they don't make them for Cessnas, but the heavy iron needs them and pilots need to know them well. Incidentally, "maneuvering speed" is the lowest speed at which it is possible to load the airplane to it's G limit (6 for the Cozy). They call it maneuvering speed because that's the highest speed at which you CANNOT overstress the airplane. That's the speed at which you want to penetrate T-storms and conduct ACM. <...If you can pull 6 G's at 160 Kt, you can do it at 130 Kt...> NO! You can NOT!. Do the math. If "miniumum airspeed" is 60 kts (for the sake of argument), you can't make a level turn AT ALL at 60 kts. At 120 kts you have 4G available, at 180 kts you have 9G available. <...if it takes 2 seconds for me to roll to 60 degrees and I maintain that at 100 mph, I've got about a 125 m radius turn. Having practiced these many times, I can tell you that it looks like I'm spinning on the inner winglet...> But if you would pull to buffet, you'd get a 110 m radius. You're not in a max turn unless you're stalled. For our purposes, use "light buffet" like I alluded to repeatedly throughout (all of) my post(s). 60' bank only allows 2G level. Go to 120 mph, pull to light buffet (which will be 4 or 5 or however many G that airspeed will support) and you'll be turning even tighter. In the interest of caution, I'm assuming you have no reliable notion of what 5G feels like, so it would be a good idea to avail yourself of a G-meter before you get too deep into this. But, basically, get yourself 100 mph, a steep bank and pull into a light buffet. then go to 120 mph and pull to buffet (whatever it takes). Tell us what you discover. The basic issues here seem to me to be: A. G-load for a level turn is IIRC the cosecant of the bank angle (1/cos BA). B. Turn radius for a level maximum turn plotted against airspeed then becomes a (slightly modified?) hyperbolic curve with th vertical asymtope(sp?) (turn radius) at "minimum" speed (infinite turn radius) and the horizontal asymtope at the x-axis (airspeed). I think I didn't describe/articulate in sufficient detail what I meant by "max turn" and "buffet", and that you didn't try as hard as you might have to decipher my jargon .... I think that, once again, we find ourselves in Violent Agreement... :D

<... Looking at the CAFE report, it mentions 30' degrees per second roll rate. So either a) pulling a max rate would take 3 seconds to 90' bank ...> Sounds like you're confusing roll with turn. What you've done is put in full left stick, and in 3 sec you have 90' bank, but you're still heading north. <... b) pulling an Immelmann (sp?), which I'm lead to believe is the fastest way to reverse direction, should take 6 seconds for the 180' degree roll ...> I seriously doubt it's the fastest way to reverse direction. As you pull up, you keep slowing down, and you have to be able to fly after you roll out on top. You could do it in a Cozy, but you'd have to start pretty fast and you'd not have much to spare on top. NOT a maneuver for the box canyon scenario (you haven't nearly the entry airspeed you'd need to pull it off). As a matter of fact, for max rate turns, G rules. Consider: your level turn radius is a function of speed and how many G's you're pulling (increases with speed, decreases with G). The number of G's you can pull is a function of the square of speed. So if you double your speed at a given amount of G's you double your turn radius, but by doubling your speed you've increased the G's you can pull by a factor of 4, so if you pull all those G's, you reduce your turn radius very substantially. Theoretically, if you were structurally able to pull enough G's, you could fly up your own ass. What that all boils down to is that you're turn radius decreases with increased airspeed provided you pull all of the G's you are able to at a particular airspeed. At some point (maneuvering speed) you've reached the point at which you can pull all the G's you're allowed to and that's your minimum turn radius. Sounds counter intuitive, but it's so. Again, we're talking level turn, and you have to pull to buffet at whatever speed you're at. If a Cozy will juuuuust pull 4 G's at, say, 130 kts, and will juuuuust pull 6 G's at 160 kts, and you're at 130 and I'm at 160, I'll turn inside you every time. <... c) a wing over, again 3 seconds to 90'; it seems three seconds are required to be at 90 degrees to your original path of flight. 200 mph is 100 metres per second, so even from high cruise the Cozy should be able to turn 90' in 300 metres or less...> You're confusing pitch with roll with turn. What a wingover buys you is it allows you to turn around in a tight space. Not as tight as a hammerhead (you can reverse direction in a canyon with a width that juuuuust exceeds your wingspan) but it does (or can) approach that. It's not a level turn, it's not even done in one plane, so the rules in (b) don't apply, but it's comfortable and easy, safe and most important, has the lowest entry airspeed of any of the choices. Modify it a little and it starts looking a lot like a hammerhead but not nearly as abrupt.

<... I wonder how much trouble it would be to turbocharge that monkey...> Offhand, I can't see where it would be much different from fitting a 13B with aftermarket gear.

<... Remember - Jim's flying a Velocity at 125 - 150kt. The Cozy at 200+ will be a LOT quicker to turn...> True. Although my references to maneuverability derive from flying my Long-EZ (O-235, 140-160 kts). Go a lot faster and everything happens faster. <... I really wish I hadn't mentioned the mountain, or the clouds, for that matter...> So do I. Since it was not particularly relevent or useful and generated more heat than light, let's pretend that part of the discussion never happened. <...It's just that in one ear I'm hearing Berkut drivers blacking out at 9 G, yet in the other ear, pulling the hardest manouevre I can think of, from 200mph, only results in me stalling inverted at 20mph. I'm guessing there's some middle ground...> There certainly is. Interestingly enough, that's exactly where the reality lies.None of these airplanes will maintain (that's a key word discussing hi-G) 6G or even 4G for any length of time. Truth be told, even fighters can't maintain a 6G level turn in basic engine, much less 9G. It's not so much what kind of G you can pull, but how long you can sustain it and what you have to do to sustain it longer. That varies both with airframe and engine (but let's talk just canard community here). An O-235 Long-EZ will not be as acrobatic as it's O-320 brother, and will pale alongside an O-540 Berkut. All will do overheads if you start fast enough but obviously the O-235 EZ (mine) has to start a lot faster (like 170 or 180 kts or so to complete a decent loop) than the 240hp Berkut. As John Slade pointed out .... <...acclimatization ... heavy G aerobatics ... concentration on recovery from unusual positions ... get used to being totally disoriented (under the hood) ... making the RIGHT moves to recover ... more prepared ... for the JFK jr syndrome ... problem with disorientation is that you're likely to make the WRONG moves and make the situation much worse very quickly ... training teaches you to read the gauges and totally ignore what you're butt and ears are telling you...> That is exactly the point. That's where this whole discussion was/should have been going when we got sidetracked by all the silliness and minutae. Most of that is on me.Thank you John!! <...I heard of a Long EZ climbing in a steep turn, that sort of information can save your life...> Yes, but only to the extent that you know how long you can climb in how steep a turn before you run out of peanut butter. That varies so widely from one airplane to another that you have to work it out for your own ride. It's fun to see how long you can sustain these types of maneuver and work out how best to recover when the initial maneuver ends. An excellent example of this line of thought might be the guy who was flying up a canyon, trying to climb out of it. The canyon got steeper and narrower faster than he could climb. He ended up killing himself trying to make a level 180 in too tight terrain. If he'd practiced wingovers and hammerheads and the like, he'd have known how much space, altitude and airspeed he needed to make his "emergency 180". But he hadn't. Pontificating that he should never have entered that scenic valley (which is what it was before things started deteriorating) begs the issue. I think we're getting back on track here.

<... Is the roll rate really that slow?...> Just how close is this mountain? Yes, it's pretty slow for the maneuver you're proposing. Would full power, full rudder with stick hard over and back not allow a fairly good attempt at reversing direction? ...> Probably. But you'd then be IMC, very low, in an unusual attitude (probably inverted by now, what with everything on the stops and all) and all the controls 2-blocked. So now what do you propose? The hurrier you go, the behinder you get .... g'night my eager friend.

<... Just to confirm from high speed (200mph) it is possible to pull a max rate to the limit ... have me going in the opposite direction, and the wings won't fall off? ...> Sure. But if it's raining, your paint job and a lot of the filler on the leading parts of your whole airframe (not to mention the leading edge of your prop) will be a receding memory. I eroded the sh*t out of the outboard 1/3 of my composite prop at 140 kts or so. But to each his own.

A guy on the rotary list has a brand new (2000 km) RX-8 Renesis(sp?) engine he's putting on E-Bay to start at $3600. This puppy comes at you at 220+ hp, box stock, NA. He is too far along with his 13B setup to start all over again. Sure do wish I was ready for an engine.

... I wonder if following an airliner to close on approach could be classifieds as tower error or more like pilot error? ... I wonder if it really matters to the poor slob that gets flipped ... ... Airframe, perhaps, but not the pilot ... Agreed. Back in my early 30s I could pull 4G all day, at 5G it was maybe 60 secs (depending on I'd been up to the night before) to tunnel vision, 6G was maybe 30 secs or so to tunnel vision, and I plumb blacked out shortly thereafter. Interestingly enough, I have never experienced sustained negative G, and about -2 for about 2-3 secs was the most I ever saw - once. Rumors to the contrary notwithstanding, ACM very rarely involves negative G. That said, my EZ wouldn't hold 4G for any time at all. It slowed down so fast I was into a high speed stall after just a very few seconds. It takes a very steep spiral to maintain that kind of AoA. Level, you run out of peanut butter almost immediately. In an attitude where you can maintain 4G, you run out of altitude in less time than it takes to discuss it. If I ever had opportunity to do some negative G like No4, I would have to pass on it. Remembering what 5G did to my legs way back there in my mispent youth, I'm quite certain that -3G would stroke me out immediately. I'm not prepared to take that chance for a marginal thrill. ... being in IMC and suddenly seeing a mountain fill the windshield, is it capable ...> Why in hell on earth would you let yourself get into a position like that? That said, probably not for me. In order to keep my prop and paint job from eroding away, I fly at around 120 kts max enroute and 100 on approach of it's raining. As a practical matter, if you broke out of the klag and saw nothing but green, you couldn't make a 4G or 6G level turn because the Cozy rolls so slow you'd be in the trees before you had any bank at all. If you pulled straight back, you would probably stay out of the trees (for the moment) but would find yourself waaaaay nose up, IMC, at maybe 40 kts trying to figure how to finish a wingover or something in the 1 or 2 seconds you have before you are at 20 kts and have lost all rudder authority (you've already lost pitch or roll).

The reason I like the wing tanks is that they are removable (takes about 10 min). The back seat bladder is also easily removable. That's why I favor it. It installs/removes quickly. Converting the baggage part of the strakes to more fuel will affect CG. Most of the baggage area is forward of the CG and it is biased pretty far forward. The strakes are the only permanent change under discussion.

No4, Sounds like you've got it worked out as thoroughly as Dust. I bless you. I wish you well. Keep us posted on progress. Jim

...my first plan of attack is to recover as much space in the strakes as physically possible....> <... didnt want to make too many permament changes since 90% of my flying is going to be around the islands ...> Isn't that a bit of a contradiction? I the basic airplane provides you plenty of fuel for the islands. Don't give away something you're going to want back. Rear seat bladder or external tanks should give you plenty of fuel to make the mainland. You'll want something besides fuel tanks, a toothbrush and a change of skivvies when you get there.

I was alluding to bearing loads at TDC and during the [early part of] power stroke. Do reciprocating acceleration loads exceed compression and combustion loads of a turbo diesel? ...power to weight ratio’s are gaining quickly on gas, and they are bringing there incredible BFSC with them ... No mention here of the company who is actually flying that diesel that you have to throw away after 2000 hrs. Or why Zorsch and all those folks have been "developing" aircraft diesels for 15 or 20 years and have not been able to get anything light enough and reliable enough to fly. The loads on the drive train of a diesel are HUGE compared to gas engines. Absent compelling evidence I will have to be very skeptical of diesel engine having the same weight as a gas engine of similar displacement. Someone's going to have to show me the science on that part.

I heard of one a couple of years ago, but it was wake turbulence from following an airliner too close.

... A centrifugal compressor has an effective compression ratio of up to 3.5 to 1, ... a simple turbocharger will maintain you sea level power to about 20,000 feet .... 75% power will be available at 25,000 feet ... I had thought that 3.5:1 would "normalize" you much higher than that. 1000/3.5 ~ 300 mb or a little less. Looking only at pressures, I recall that the 500 mb level is right around 18k', and the 200 mb level around 35k'. That would put the 280 mb level at maybe something over 25k'. Now, take temperature into the equation and you have a density altitude of .285 which would indicate your 'critical altitude" (and onset of power decay) occurs at something on the order of 28-30k' wouldn't it? But of course this is all pretty academic. Turbo normalizing to 20k - 25k would require the prop from hell. You'd need a CS unit that could be pitched pretty coarse and very wide blades. Your mission profile would be a little wierd, you'd have to be IFR on a hard altitude ALL the time, O2 ALL the time and a pretty robust cabin heater (whose weight might help offset some of that mass back aft. As to diesels, it was brought up that a reciprocating mass is bad for engine life - ALL of the components involved, from the crank and main cap to the wrist pin and piston - and even the block. The higher the pressures on the piston the more detrimental to the engine. Isn't that why the really reliable diesels (like on generators and line haul trucks and the like) have power/weight ratios of arouond 0.2hp/#? Additionally, diesel compression and power stroke numbers abuse bearings hellishly. Which is the aero diesel that has no TBO - you just junk it after 2000 hrs? Do those folks know something we don't about what happens to structure when you pare down the weight to meet aero application requirements? As one might infer, I much prefer three moving parts and a rotating mass. The fuel specs aren't as desireable as a diesel, but the power/weight ratios are quite good and they have enviable reliability (race teams running recips rebuild their engine after every race - rotary teams rebuild at the end of the season - whether it needs it or not:)). A rotary costs something on the order of $3000. Firewall aft (engine, PSRU, fuel and cooling systems) can be set up for under $10k if you only do it once. TBO is unknown at this point but indications are that it could exceed 3000 hr. A rotary can be rebuilt for around $600:). Props are another matter. CS props cost a fortune (both to purchase and to maintain). One that could provide a Cozy with efficient, full power cruise at 25k' and 200-250 hp may or may not exist at the moment. They weigh a lot, and are located where that weight will do the most damage. For the money, I'll take my ~220 hp NA to 15k' and cruise at something upwards of 200 kts and spend all that other money elsewhere. $30k or more for a turbo-diesel engine, $12k for CS prop will bankroll my $10k - $12k firewall aft, a nice radio stack, a brand new BMS EFIS with all the trimmings and an Infinity retractable gear. I'll TAKE it!!

OK. Let's examine this deal for a moment. Think it through .... Military drop tanks start at 300 gal (that's 2000# of JP5) for smaller fighters, up to 450 and 600 gal for thuds and 3000 (that's thousand gal for BUFFs. The tank might weigh maybe 10% of its capacity. Not a good source for our purposes IMO. That said, your tanks are already available - just get a couple of baggage pods and seal them up. They come on and off with a few screws (which you'd probably have to beef up a little) and look like about 10-15 gal. Readily available and easy to adapt. About transfer: The military transfers with compressed air (readily available, no moving parts or mechanisms inside the tanks or pilons). I think that would be our best way too. I would envision perhaps a 3/8" Al tubing permanently plumbed through the airframe (ending in a cavity under the wing, over the pilon with an access door). The air line and fuel line would be plugged when not in use. Only the few oz of plumbing would be permanent. Air and fuel lines would be connected as the tank was mounted. All you need is a reliable seal on the tank filler. An electric air pump (3 psi or so would suffice I should think), installed, plumbed and wired when tanks are installed would flesh out the system. For procedures, one might have a little inspection window in the pilon through which you could see the fuel transfer when you turned on the air pump on momentarily during pre-flight. Enroute, while you still have sufficient fuel to return to your departure point (just like the military does) turn on the transfer and watch the fuel in the strake increase. When transfer is complete, turn off the transfer pump and continue the march. Now you've got it, what are you going to do with it. It has already been made clear that the airplane will already outlast all but the most outrageously distended bladders, so the tanks would be very little utility in the contiguous states except perhaps for Greg Richter. Relief tubes have been mentioned. Don't know how many of you have ever used one, but you have to be hung like a bull to avail yourself of the facility without making a terrible mess. Pampers come to mind. Which pretty much leaves us with substantial trips over blue water. We could visit Hawaii (if the engine could be relied upon to make the trip) and our Hawaiian brethren could fly to OSH. It would appear therefore, that we have two candidates for further development: Greg Richter and (whatshisname) in Hawaii. And, of course, all the folks who are turbocharging Mazdas. The former are a pretty thin market; the latter more numerous if less motivated. Did I leave anything [important] out? .... Jim S.

As was discussed earlier, loops in our canards look like a script/cursif "l" - starts out looking like a loop, runs out of peanut butter at the top and only gets a little past vertical where the nose falls through very fast (like a hammerhead with no yaw) and starts flying again as the nose approaches vertical (down). At forward CG, the airplane WILL fall through. At partial fuel conditions, the fuel will slosh back to the spar, but will slosh forward again as the nose falls through (this could be something between a "shift" and a "migration" of CG) but with any rotational velocity at all (which it will definitely have) momentum will drive the nose through the horizon and on down and the fuel will slosh on to the front of the strakes. As I said before, the CG needs to be WELL within limits (nowhere near aft CG). I have talked to several guys who have done overheads in their EZ and NONE of them were able to maintain any noticeable positive G over the top. They were barely flying (if they started REALLY fast) or else the airspeed bled off to nothing somewhere past vertical and the nose fell through and they continued the maneuver/recovery. That's the best information I have .... Jim S. In any event, it's not much fun IMO to do even barrel rolls or aileron rolls in an airplane that has to struggle so hard to get through them at all.

I think there is one out on the left coast. A Ford 351 Cleveland IIRC. I believe it IS direct drive and competes in the RACE events. Look up the RACE results and you'll see what he can do. I don't have any particulars (not even sure of engine make) but it is all in past issues of CSA newsletters. Check their index.

The attitude of the airplane does not determine CG. Nor does any fleeting aerodynamic condition. CG is determined by weight distribution in the airplane that may "migrate" but does not "shift". Actually, an EZ, Cozy, etc. will recover nicely from a hammerhead type maneuver provided the CG is (well) within limits. With the CG within limits, the airplane will fall right on through the "deep stall" attitude and end up flying - straight down, perhaps, but flying all the same.

It's true that increasing rpm/power by 25% would also increase heat rejection requirements by the same amount. Attaining the same increment in power with a turbo would cost more in heat rejection. Doing the job with rpm, I'd be saving all the turbo overhead. The folks on the Mazda list have pretty much determined that the first 5" of boost (with the heat and fuel burn that 5" brings with it) get you back to the hp you had before you installed the turbo. The next 20" buys you all the increased power (also at the price of fuel burn and heat rejection). Soooooo, if I do it with rpm instead of turbo, I save the turbo overhead (which I believe is considerable). I get the power at a lower price in fuel burn and heat rejection, but I don't have the muffling and exhaust taming and I don't get to normalize my power at altitude. Turbo normalizing at higher (than 10k) altitudes is real iffy with a fixed pitch prop anyway, so I haven't lost a whole lot. Anyway, it's a way to go .... Jim S.

.... Simple aerobatics .... Key word there. Wingovers, aileron rolls and barrel rolls qualify as "simple" aerobatics. You can do them in an EZ or Cozy (albiet somewhat marginally). It would be a VERY good idea to first actually do a bunch of those things in an airplane that is designed to do that stuff and is more forgiving of errors. Then try them in your Cozy but: a) Be at an altitude such that you have plenty of room to split-S, b) remember always that split-S is the worst possible way to recover from a botched maneuver and NEVER do it in a canard.

...Shirl Dickey helped Jack try to figure out why it was having heating problems... Shirl Dickey knows EXACTLY why it was having heating problems. The same reason Shirl had heating problems for fifteen years!! You put the engine in the back seat, and you can't cool the $*(&%&& I saw an E-Racer at OSH a while back that had an O-540 or something of the sort, and it flew nice (engine was mounted aft of the spar). I think E-Racer had one of those ... I think they call it a "design defect". One of those really dynamite ideas that just didn't quite work out. As for extra power: All the 13Bs are running at around 5500 - 6000 rpm with a 2.1:1 PSRU. They get a good honest 160-180 hp NA (perhaps 190-200 with "street porting). I wanted 200-225 with street porting and was pretty much resigned to turbo, even knowing that there was no way to reject all that heat or load enough fuel to get anywhere. Then the guy says "... Jim, if you want 25% more power, why not just run the %&*(^)& thing at 7500 rpm?...". DAMN!!! Why didn't I think of that?! As we speak, Tracy is working on a 6-planet PSRU with a 2.83:1 ratio. 7500 rpm ==> 2650 at the prop, and street ported 180+ hp becomes 220+ hp. And then, there's the Renisys engine that comes at you with 220@6000:) ... Jim S.