Arbiter

Merry Christmas to everyone! . and a BIG THANKS to all those who gave me advice so far! -Chris

Hey Folks. Some simple questions, not so simple answers I am sure, but that's why I want to generate discussion. Here are the assumptions I want you to work with: -2 Seat aircraft -Long trip of at least 5 Hours 1000 NM (200 Mph) -Going to suprise your spouse with a fun time away from home for a long weekend (Friday-Monday). -Possibly over water, but does not have to be -~300-400 Lbs of fuel to do the trip in -Going to fly the whole distance in one shot -NOTE I AM NOT ASSUMING ANY AIRCRAFT CONFIGURATIONS (DON'T THINK LONG EZE OR COZY ETC... IT'S A RUBBER AIRPLANE) The questions: What kind of gear would you take, and how much do you think it would weigh? What kind of baggage would you take, how much weight and approx volume? What would be a good combined weight (Be realistic) of the passenger and Pilot (Just a lump sum will do)? Where would you go (This is the fun one)? My Answer: -Life preservers (Flotation device of somekind, could be a seat cushion), emergency kit, snacks for pilot and passenger (Including nalgene bottles of drinkables) and some sort of potty kit (ewww but hey. - 25 Lb -I would take rolled up T-shirts, shorts, etc, toiletries, wallet ~5 Cu Ft. .. -20Lb -Combined passenger and Pilot Weight (Max) 650 Lb -I would fly from Cincinnati back to Albany NY for Christmas with the Family. As I see it, totaling that up gives Needed useful load of ~1100 Lb for 2 people at that range and comfort level. I am just trying to generate discussion on what people actually carry when they're flying this kind of mission; flying from point to point for a long weekend. Thanks, and I look forward to discussion on this topic! -Chris

To Aiman's defense, he wasn't trying to do any evil, only update some old plans with modern word processing technology and drawings... If it's copyright infringement it's copyright infringement, and I believe he meant no ill will, and he has subsequently ceased the forward progress he's been making... I think everyone's coming down hard on eachother here... If it really is infringement (I'm not a lawyer) then the right thing was already done. I for one am sad this did not come to fruition, the plans could use some updating and tweaks, but I understand we're dealing with a business' property and we have to abide by the proper laws. I own the TERF CD and from what I've seen some of the old newsletters are hard to read, and the images are scanned in to PDF so I can see why some one would want to do this. Personally I think this show was something that should have been taken up off-line by private message... Let's bring this back to civil tones. As I see it Aiman tried to contribute in a big way and he had a good idea to modernize the plans. -Chris

Though the Cozy isn't designed to to Aerobatics, and the designer is rightly covering his posterior when he designed the Cozy, I can recall one really sweet display of a non-aerobatic plane doing a Chandelle: http://www.aviationexplorer.com/707_roll_video.htm And before I get pounced on for calling the plane the 707, it's actually the Boeing Dash 80 rolling over a crowd at Lake Washington..... All seriousness asside: "If Dash 8 Can, Cozy Can" .... PLEASE NOTE HUMOR. This is supposedly a 1G manuever, so from a loads perspective it would be perfectly alright, but from getting fuel to the engines/aerodynamics, that's out of my experience on aerobatics ..... Enjoy! P.S. If you are going to attempt serious aerobatics, and from what I gather that's not a good idea, I recommend Danger Zone by Kenny Loggins :-P

Thank you Marc. When I was in school I was told a Canard configuration would out-perform the conventional architecture. From my basic understanding, this was due to to the fact that all of your horizontal surfaces produce lift, unlike the downward lift on the horizontal stab of conventional architecture. This would drive the area of the main wings down for a given wing loading compared to a similar conventional plane. The rest of the wing load would be carried by the canard, but for longitudinal stability (pitch), you no longer needed the area of the horizontal stabalizer which produces downward lift to counter-act the nose down tendancy of the plane in level flight. To me, this means less induced drag and less skin friction drag, thus higher efficiency. Is there something I am not looking at right here? I realize there are many other factors that go into the overall system, but I'm trying to keep my thoughts as simple as I can. To summarize the point of view I was looking from, if two equally capable designers designed two airframes (One canard, one conventional) to the same specs, weights, etc... The Canard would be more efficient for the reasons I described above. Again, this is the impression I was left with in school. I am sure this will be debated until the end of time, but that's the paradigm I came into this conversation with. Thanks for the good discussion Marc! -Chris

Marc, I'm not going to go head to head with you. I am an entry level engineer Vs. a seasoned clearly well educated individual who wants to be precise. I admire that. That said, I have been doing research and reading (Right now Rich Von Mises' Theory of Flight is sitting right next to me, highlighted like crazy), to imply otherwise is a little disappointing. All I was trying to say was a Cessna doesn't have the same range, payload, and speed as the Cozy for a similar fuel burn, and to me, that is an efficiency. You are completely correct that in order to do Apples to Apples comparisons of true performance data you need to break the systems down and study airframes of similar design missions and cert requirements. Who has the time to do that though, especially if they're building? Also, from my perspective (see above), what I am saying is not un-true. If one of us takes off in a Cessna 172, and the other in a Cozy, the MkIV will get to a destination faster, and on roughly the same amount of fuel, with more payload capacity. To me, that's an efficiency. Is it the engineering definition, or an aerodynamic L/D point of view; no. Is it a less fuel is burned point of view, certainly not. But it's an efficiency of time. Does that clarify my thoughts enough? I am sure you'll have an interesting and surely more thoughtful perspective on what I just said, so I'll just wait and see what happens... Take care! -Chris

Marc, I should clarify my thoughts a little. From an efficiency standpoint I meant that a Cozy for example can carry more payload at a faster speed over a longer distance than a Cessna 172, a cursory study of their website proves that. I am not sure about a Cirrus and how it compares since it at least looks more slippery and more aerodynamically adept. It sure seems more efficient at the same horsepower than the traditional 172 to me. I guess I'll go on continuing to be mis-conceived . -Chris

I admire your enthusiasm with the cadillac engines ... Maybe we'd translate that to Rolls Royce Merlins... Anywho, I do think we need a bigger plane with more payload capacity. In general this will mean a larger engine = more fuel burn, but the Canard arrangement will be more efficient than a conventional airframe by nature for any given size. -Chris

We really need an aircraft that is a Canard and not $$$$$ like the Avanti that seats comfortably 250+ lb pilots, pax, and full fuel load. No reason these people should be shut out of flying these awesome planes. No mods, no nothing, I really think we ought to have an aircraft that can carry this kind of payload aloft. Right now we have Canards that carry up to 1100 Lbs (I think this is what Velocity says anywho), but it still won't carry 4 full sized adults, baggage, and fuel and the engine is Megabucks and is 4 place instead of the 2 place I want to build. For better or worse, we larger people do exist, and losing weight to enjoy this sport may not be feasible, nor should it be a requirement. As I see it an aircraft that will carry that much will either carry a couple big people in the front, or standard 180 lb people and a whole lotta baggage or an extra fuel tank for extended range... Or that elusive lavatory someone suggested . -Chris

Ahhh, poor Goose, RIP man! -Chris

I prefer the housian approach on Fox Tuesday nights .... But I agree with what you said Drew, we've sharpened our arguement well . I will just put it forth that if you don't have experience in structural analysis or aerodynamics you will want to hire a competent engineer to do the re-design for you on more involved mods... Again, this is all aimed in my mind at understanding the greater picture before you jump in. -Chris

Drew, I respectfully disagree about keeping people from making modifications. The key is to actually understand what you are changing. I am an aeronautical engineer, and I am trained in things like structural analysis and aerodynamics. Am I an expert, no, but I do understand in general what is going on structurally and aerodynamically with these aircraft. Before I make any of my modifications that I want to do I am planning to analyze the structure of the airframe to get a basic feel for the design margins built into the airplane. Once you understand the margins you can begin to make judgements on particular mods. The point I want to make is this, you should modify the airplane ONLY if you do understand the engineering behind what you are doing. That can come from your own knowledge or from a hired competent consultant in the field. Small mods that have been tested before are good too, but I don't feel we should discourage modifications as a group (Afterall, look at all the different cooling mods people have discussed and implemented that are different). What I think is if someone is making a big mod, they should have the analysis to back up what they are doing and have another competent individual check it over. If the person cannot accomplish the analysis I am with you in discouraging it if the mod will affect the structural integrity of the airframe. I know that people tend to discourage mods in this forum, but I say don't discourage them, but rather encourage understanding the effects of the mods before someone implements them. As far as improving our image goes, I used to think a governing body would be the right way to go, and as people have pointed out, we do have the EAA builder resources to help us along in the build. I know I plan to use my resources as much as possible, a second pair of eyes is always a good thing! -Chris

Alright, I'll take a look there! Thanks! -Chris

hey guys, I was looking @ the rev 5 drawings and digitizing them. I currently have all bulkheads shown done with exception of the firewall... The two slanted seat bulkheads I have not been able to find in the template drawings. Is there a sheet that might be missing, or where did you folks get the dimensions of the plans from for the pilot's seat and the pax seat. Thanks! -Chris

I don't know.... Doc said 1.21 Gigawatts of electricity is a lotta juice :-P... If god reaches out and touches you like that while flying amongst the angels, isn't it your time?.... Kinda like a giant bug zapper for little planes I would think. Then again, I am not an expert at all in this area. I am just picturing all sorts of bugs bunny cartoonish scenes where a person is flying along in their long EZ and lighting up like a lightbulb skeleton when struck.... Hopefully it doesn't happen because my first inclination is it's not good news for an aircraft of the LE size... -Chris

Thanks for the information Marc, I will check into it shortly. I also saw a book on Aircraft Spruce on composite structural analysis. I'd like to try some hand calcs if possible to determine if the loads I am thinking of using are reasonable using stock LEZ lay-up and structure. This won't be for a while since I'm working through a compressor design course right now and I'm going back to school in January (Maybe I'll have time then?!?) to finish my masters in ME, but when I am working on it I'd really like it if someone would be willing to check my work and assumptions. I have some guys here at my company that may be able to help too, I am interested to see what a simplified analysis would reveal, just got to make sure I capture all the relevant assumptions and know the limits of the calcs. We'll see, it's an interesting engineering problem either way . Thanks for the input, still would love to have some more data about people's gross/empty weights that they fly with for LEZ. Check back l8tr! -Chris

Marc, Thanks for the reply and the input! . I wonder, does anyone think it would be overly difficult to incorporate the COZY IV wing and canard layups into the LEZ, has anyone done it before? Marc, do you have any suggestions on a good book or resource to learn about aircraft sandwich composite structures like the LEZ and their analysis? Thanks! -Chris

That was what my question was going to be. When I looked at the Cozy initially I saw the 1000 lb useful load, and from discussion I saw the wings were the same with exception of the strakes (Aerodynamically at least) and so I deduced incorrectly it seems that both aircraft would have roughly the same useful load. Could someone with more knowledge than I go a bit deeper into the differences between the Cozy Useful Load and the Long EZ? Thank you for all of your insights so far! -Chris

The Long EZ is suiting me just fine so far given the data we have here. Probably will have an up-graded engine and be a bit over-gross, but I am not expecting 1100 lbs useful load like Cozy either :-P, probably ~ 810 lbs useful with 2 pax, bags, and fuel which is within experience (At reduced G Loads and V Speeds for rough air). If I was to go full fuel and all the bells n whistles I'd be at 270 (Pilot)+220 (PAX, not the wife , she's much lighter )+20lbs (Bags)+300lb (Fuel). I wonder if you could stick COZY wings and Canard on LEZ Body , just a thought, but perhaps for another thread . I wouldn't likely carry full fuel either since pit stops are more frequent. Thanks for the comment though! I am sure this will generate more discussion so keep it coming! -Chris

Wow, there are a great many posts in here, and good discussion about the potential concerns very well educated people have about flying over gross. I agree with everything that has been said so far in terms of being cautious when flying over-gross and if possible, executing a test plan to know your limits. That said, what Juhl-EZ has posted shows that at least the airframe of a number of LE's have been successfully flown at higher empty weights, and Waiter has shown he flies near 2000 lbs. With Marc's discussion on decreased G loading and V speed adjustments, it seems prudent to execute a more extensive flight test program to determine the safe operating envelope of the aircraft. I am hoping from the discussion that I will be able to remain under the 1000 lb mark for the structure and maybe try to allow 270 lb pilot, 200Lb pax and partial fuel and see where we get. Please keep data coming as you are willing to share it, bearing in mind the great discussion above. I know I certainly appreciate everyone's thoughts so far as they are candid and presented with detail so the community can understand fully where the data is coming from! Thanks again! -Chris

The Pilot Operating Handbook says 1425 is acceptable for take-off.... That's higher than 1325. Waiter is flying @ 1700 lbs... I am assuming he feels decently safe or he would not fly like this (and I am assuming he wouldn't post something he feels would be un-safe)... Please folks, just post your numbers and Qualify them as you feel you must (Waiter said his runway length increased for example) to ensure people understand the potential differences of your situation (Large engine, bigger retracts, wanton dis-regard for one's self, etc...). Bottom line is we don't know if it's safe or not... We know it's not recommended per the POH, but that assumes a stock LEZ, which may have a smaller engine etc... that's why I'd like to learn what other people have done scuccessfully. Please post weights that you use regularly. If you use 1325, let gross be 1325 for you. If you have flown at higher weights than that and feel comfortable with your design, please post your weights. Thanks! -Chris

Marc, Thank you for your input. As always, you make things many of us are unable to articulate more clear. That said, my original question was what is the useful loads people have on the LE's. Yes the POH says 1325 or 1425 TKO Max weight, but like you said people haven't been bitten yet, even with decreased G load capability and changes in speeds. I have looked at the forum and seen wide ranges in speeds and engines people have that exercise this design (Though you are right, we don't know how much), and I am trying to get a good cross-section in this thread of what people's planes ACTUALLY weigh and what they ACTUALLY carry in "safe" operation. Let me qualify that safe operation to me means they've been flying with these loads for a while now and feel comfortable themselves with these loads. With that spirit, I humbly request more data points for long EZ weight and engine data . Thank you for the posts so far, and we must all keep in mind what Marc says, the design clearly has limits we cannot know at "off-plans" conditions, and we clearly have people flying outside of those limits with success, so I'd like to hear you sound off! -Chris

That's good to know. But does that imply the airframe is weight limited by the gear at the normal 1425 lb? Please post data, and to Tmann's point, if you know of any mods that affect your numbers let us know, keep the good points and loads coming! -Chris

Just buzzing through Spodman??? On with the useful loads of the Long EZ :-D * Dons Viking Helmet * and Immigrant Song by Led Zepplin begins to play.... plz post load information asked for above so we can get a good database of load and engine data. Thank you! -Chris

Looks like Waiter has a bird about 300lb heavier than Burt's 1425 lb max gross than what I saw in the pilot's handbook I just found. Is this ability to carry more due to any design modifications other than the engine, you said you have an O-320, what's your fuel burn with that engine and that weight? Thanks for sharing, keep the loads coming! I like how Waiter did it, if anyone else wants to I would suggest putting their loads as follows: Engine Empty Weight Pax + Pilot Weight Baggage Weight Fuel Weight Gross Weight Fuel Burn (75% @ ____ ft) If many people contribute to this thread we'll have a good idea of what the current and flying long EZ's can do, Thanks! -Chris