Obviously just using composites is not enuf--I don't know the details of Jim's earlier attempts but my guess is that they began with FWFG tubing, a material many naively believe to be Mach 2+ capable. In fact I have heard more times than once FG is as strong as CF from very seasoned rocket guys. But why try for a ne plus ultra shot w/o getting some experience first. It was Icarus like approach and he was punished for his hubris, but in the end had the last word.

Perhaps, and I know this ain't your cup of tea, that part of the problem in trying to break 30K with a single motor, is that you just have to roast it.

I've simmed this problem from multiple approaches, and to keep the stresses, including heat, down, you need to fly below M2, preferably about M1.8 or so. Then your epoxy doen't melt, either by heat transfer from the casing or frictional heating. Thats the premise of my current project, in fact I'm sacrificing altitude by not drag separating, coasting until below transonic, etc just to keep the profile mellow. I believe this is a well thought out plan, and will bet anyone a steak dinner I make it to 25k at Balls, even steven, and if I break 30K, I get to pick the vendor, otherwise Outback. 😛
John S

Well how he acchived his goal is inspiring.(from what I heard this was not his only CF build) Hats off to him.. BUT the fact that it went to 35K is great BUT I think unacceptable for a L3 flight and could easily cost him his Cert if the cert team followed the rules completly, But thats another subject all together. As far as FWFG being Mach 2 capabale.. Heck yes it is. Ive proven it myself with a Mach 2.2 flight myself. 3" diameter rocket only about 7 to 8lbs and a really fast 54mm AMW engine.(when I got it back the paint was scorched and burt off from the air friction moving around it) Jim Amos flew his almost to the same size bird on the same engine with his Mpac and recorded Mach 2 and its a partial FWFG project. So yes its very possible. So I dont think there is any naive thoughts about it. CF is not the so called champion of indestructables as everyone thinks. Lb for Lb its streangth is great dont get me wrong. But I have seen several CF rockets that shreaded as easily as any. In fact the place here locally I get my CF and my Fiberglass and epxoy and stuff has told me many times that FG is as strong as CF but CF is more rigid and has a different freq of dampening the FG. I to have heard that FG is as strong as well. Infact the PHITS club proved how strong a FWFG airframe is...

John if you break 25 or even 30K my hats is off to you. Great achivement! (has to be a clean recovery) But the previous Altitude that has been in this discussion as to being easy as its so put was 50K.. You break 50K and youve got a deal on outback and the steak. But as I stated. Must be clean recovery and wittnessed.. Once I get my L3 done I do plan to start putting together a build that will take a few years . 2 to 3. Single motor. something in the P,Q or R class. Then I will go hunt me down some Big sky. I may not find the multi-staged stuff as appealing to me for the altitude as I do the shear brute power of a single motor capable to do the same but I still think they are pretty cool. I gues its just the big horsepower lover in me that comes out there.

Con,

And I have seen as many FWFG tubes shred at Mach 2+ as you mention surviving it--may be the vendor involved, wind shear, etc. who knows, certainly there are many variables. FWFG tubing is a great convenience and certainly more affordable than some of the more exotic stuff, and off the shelf ready to go. But having seen it come apart, I took it off my list for Mach 2 anything. Now maybe wrapped in kevlar and CF it might be close to ideal, on account of its great insulating properties and general ease of use. I would hazard a guess that a FWCF tube would be the ultimate cats meow.

But of greater curiosity is why you consider 35k unacceptable for an L3 shot? Obviously not the road either of us are following, but it was 15k under waiver, stayed within the cylinder the entire time, and passed muster with his committee. One could argue it might put spectators in danger, but any L3 shot can--personally those flying bricks of 60# plus make me more nervous, but obviously just an opinion.
John S

As far as tubing goes I agree that FWFG is probably not the most superior ..but its does do a great job. My preference is to Convolute made products like Convolute wound FG tubing or CF tubing. anyhow..

A far as the cert. I dont want to be jugded as a spoil sport or negative. Just pointing out what I have read and how I belive it should be read that way.(or at least how my Cert member would read it) I may say some possiblillities but in no way am I saying that is what he did or anyone would. Just a posibility.

According to the rules of the cert, the flight has to be Visible to the Cert team. Im pretty sure that at that altitude you cant see it. So how do they know it operated like it was supposed to? Did the mains come out on top on a supposed to be dual deploy flight? There are even other possibillities that I wont even begin to imagine only because i dont think anyone would do it.. but it is possiblity..just want people to think. This is why my plans for my cert flight changed and toned down from an N4000BB to a N2020WT. the difference of a 22K flight vs a 13K flight. A rocket the size of mine at 13 to 14K shoud be visable with eyesight and even more with Binoculars. Let alon I do have Video onboard recording the flight.

Con,

i guess we'll have to continue to disagree, the GPS locked around apo, and we had reports on the loudspeaker system, 35k...34...33...etc until mains deployed when they were supposed to.

There was no chance he had a premature..um..event, and that rocket with its GPS, accelerometer & baro data, coupled with ground software like Google Earth probably has provided the most detailed depiction of an L3 shot, short of camera, as any that has been flown to date. I think Jim deserves a lot of credit for pulling off arguably the most masterful L3 flight ever. Frankly if your mains come out early as they did in the case of the event horizon, one would know. You got a huge chute and no descent. Its pretty obvious at even 11k. At 35, it drifts away never to be seen again.

Rocketry is about personal challenge. Choose your targets. Live with the results. Can go green, blue or black, even dbl diamond. Unless you're putting other skiiers at risk, go for it.
John

Yes we do dissagree with this. BUT once again read what I said it states. Its states That the flight must be seen. Not heard from GPS or anything else. BUT seen to have exhibited the correct mannor for certification. Reguardless of all the techno stuff seeing is beliving is the cert rule. It very well makes sense to me. I would belive that many of the L3cc or TAP members would belive in this as well.

Con.

Not sure what you mean by seen. The rocket was seen via smoke trail to apo, and arguably noone sees a rocket directly w/o help above 10K or in the case of my own L3, a humongo 40' streamer at 17k. Even then, only Art Hoag and a couple of other eagle eyed guys saw it the whole way down, but I certainly didn't, so what if your L3tap has crummy eye sight like mine--DQ? But Chris's dad caught the apo charge on his long lens Canon--amazing pic IMO.

This argument goes in the same bin as the NAR's insistence to visually track and close altitude events, Luddite! Ask James Russell if his L3 apo was seen at 16k or Lynn's (B'nutz) shot to 22K. Or Jim Amos's to what I can't recall-- 15 or something.

Personally, rules interpretaion at any level is sticky, but to insist that things be "seen"--which would mean below 5K--is a disservice to the hobby. Hell my L2 went to 9200'/ w/o binos might have been lost. Else folks are forced into porkage which has its owns problems, and never gain experience flying fast.

A far more credible argument IMO can be made for insisting on DD or at least electronic apo deploy as L2.

Otherwise you provvde access to huge motors w/o an ejection charge to those with no experience.
Cheers.
J

Ive had no problems seeing any of my flights to easily 13 K. that was with a rocket that was only 3 inch diameter and 7 ft tall. once again All I try to point out here is interpertations. It may not be the way I feel about it completely. BUT some or many may have belief differently. Unfortunatly its THOSE people that many or even some of us must appease to get to the end of the trail. It can happen. It does happen. Just somethings some people have made me think about and so should you. Its worth it to cover all possibilities when dealing with all the gray areas that we rocketeers seem to deal with. As I stated eairlier that it was a great flight for him but intrying to look through some other peoples eyes so to speak and see their opinion(and I try to do that in any situation) I understand where they come from on their belief. Does that make them wrong. no. Does that make you wrong..no. I could easily punch my rocket well beyond the 20K barrier and have no quams about doing it. But for the sake of what I looked at with in reguards to of maybe some others opinions made a lil sense to me. Im fine with down sizing for now and getting my Cert. there is nothing unrespectable about 12 to 14 K. Im not making choice on either side but riding the happy middle while just trying to do what I like to see people do best.. and thats Think.

Con,

I'm sorry if this may seem offensive, but you need to relax. I looked into the airspace cylinder issue and did some research, finally to agree, and defend your position. How high "you" see is not the issue. I've seen drogues at 30K. But whether on that day or a cloud gets in your way,at least by your interpretation--whether others saw it is all that matters.

Personally I think you're seeing gremlins that ain't there. This issue I will never retract on. If you want to hunker down and fly below 12 or 13 K its your choice, but to suggest Jim's cert isn't valid cuz he flew to 35K is nuts.

There we have GPS readouts every second or so, so its simple to calculate descent velocity.<= 25FPS under mains, over 120fps ballistic. No othjer choices. This data in connection with a smoketrail--i'd sign off that anytime. You can even map the trajectory arc over the launch site, and be assured he never got outide the cylinder, with a camera not as sure.

Con, if you're that worried, down scale to an M. But you won't, cuz you have the same derring-do/innovative streak we all do--damn the torpedos, and go for it. Best of luck, maestro
J

No offence is taken.. Trust me. It takes a fair amount to get under my skin as its plenty thick. Understand for me Its not a matter of seeing more into things then there is As said before I want people to think about the things that we have that are gray. We all have to sometimes opperate under the veiw of others so when doing so its always best to be alert of any of those other veiws. Like the airspace issue I pointed out. Not really anyone had been truely thinking about it until brought up. Same with this issue. Even though I myself have no issue with his cert. I only brought up the possibillity of the discussion as it has been placed as a question to me from others to make me think. It would be wrong of me to not take the given time to totally walk in their shoes and see their opinions. At the end of that I came to my own conclusions and Personally as I have stated I am not only Impressed of his accomplishment but congragulate him myself and only hope that I to can achive those higher altitudes myself. I have no issues with it at all. But others may have them. All I can say is I see their point and if I was a person opperating in their world as they were a certifing L3 memebr for my flight I should be very placent about their opinion/intepritation as they see fit. That is the complete angle my approach has been. Just to think and learn. I think it truely is what can make this hobby to find ways out of those gray areas as well as become smarter all around.

AND your right.. I am like what you described Damn the Torpedos and Full speed ahead!!. As James told me he very well expected me to push the limits of any waiver if given the chance to do my flight at as i am a past and still present Altitude junkie. Even though I have been gone for a little while I have yet to have a flight in almost 5 years that has been under 11 to 12k minimum.

I respect your veiws John as I would hope that others respect mine as making it a way for people to hopefully open their minds to the way others think.. Thats all.

Personally, when the time comes, I want to use the whimpiest M I can find (1297W) for my L3. I'm only comfortable through K's now, so I'll have to fly L at least once. I promised Joe H. I'd go up the alphabet and learn from and get a blast out of each step. Plus I need a lot of DD experience before that, whether the rules say that or not. Just because I'm building the rocket I hope will carry me through L3, doesn't mean I'm ready. Both of you are though; both more than ready. I agree when one of you wrote that we're only in competition with ourselves. It's an individual journey up the power levels. Anyone who flies out of their comfort and confidence zone, is asking for trouble. High power is like driving faster and faster. It's exhilarating and addictive, and scares the igniter out of my grain core and nozzle sometimes. Sometimes the gray in rules allows each of us to do what we like and feel comfortable with; it allows for diversity. And that's a good thing. Whether someone wants to slip through the lower end of L3, like me, or blast to the limits right out of the gate (like you, Conway and John), that's to be respected and allowed. Besides, L3 is about a level of power, not altitude, right?

Section 3.6 of the NAR L3 cert rules states all the requirements of a successful L3 flight: total impulse > 5120 N/s, stay within the FAA waiver, safe & stable flight, full deployment & safe recovery, and no separation. Not one of them says that the flight must be seen directly. It just must be witnessed. Is it total visual witnessing, or can it be witnessed via data readouts after a point? (Sounds like Clinton when he said, "It depends on what your definition of is is.") If it comes down on a main safely within the cylinder, I personally don't see a problem. One is as good as another. If it flies to 2k or 30k successfully on an M or above, it's a successful L3 cert, IMO.

Very well put Bruce and I agree. Im not really tring to be a a pain but just want to get people to think. Its the thinking about what we do or what is gray that may help us clear it up. I guess for lack of using the word witnessed and using seen, is my bad. Really what I was looking at was to just make people think about the subject of what Witnessing would detail. (unfortunatly my example here was a bad one. again my faux pas.) I wasnt in hopes to make myself hopefully look like an idiot (gotta admit I did a pretty good jub!!lol) or make anyone else feel wrong in their thoughts either. I look foreward to any and all input and discusion that comes along. Its all the difference in ways and opinions that make things interesting. BTW I do look foreward to getting to fly some rockets and hang out with all of you. Should be a great time. I cant wait to see all of your flights especially the L3 attempts from all. Anyhow seems to me like we way offed this thread in a way bad direction. My bad there. Anyhow Besides My L3 attempt at Octoberfest I have planned a K or L flight in my Talon 4 and My daughter will attempt her Jr L1 with her BSD Thor.

well then Con, we may be cut from similar cloth after all. I post many provocative messages just to stir things up--get people thinking and examining the assumptions that keep us all locked up to one degree or another. It's not the same as taking a crummy argument for arguments sake--I try to pick defensible positions, tho often unpopular ones, just to get us to put our collective thinking cap on. Frequently the iscussion which ensues is eye opening on a number of fronts. I have done this so many times on TRF that i am on the verge of being booted, which given the direction of the forum in the past year and the absolute stupidity of some of the moderators, would almost welcome. But Jeff Taylor, Anthony Cessaroni, and Gary Rosenthal post there frequently so have just gone into a self-imposed exile while the frog man finds another target.

Like Bruce I'm certing under NAR but belong to both--I see nothing about visual confirmation or even an inistence it works as advertised, only that it lands undamaged ready to rip the skies again.

Personally I like the idea of tightening down--whether explosive or not, the potential chemical energy in an m or N motor is sizeable. There should not be wild skywriting episodes at LDRS like the N-M 2 stager that went amok and landed in the camping area with the sustainer still lit. The rocket so far as I know had no operational propblems apart from the fact it WAS UNSTABLE!
John

I contacted Jim Jarvis re his L3 flight, addressing prior failures and his notions re visibility, his response follows:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

John,

I'll try to answer your questions as best I can. If you want to know
anything else, I'm an open book.

Here's a brief summary of some of my flights. A picture of my current
fleet is attached.
- First flight ever (since BAR) on a G
- Second flight was an L1 cert on an H-101 (I think)
- Third flight was an L2 cert on a minimum diameter dual-deploy nimbus to
over 9K (starting a trend)
- Roughly 50 more flights before my L3 attempt
- A two-stage Quantum Leap shred at Wayside (which led to improved
construction practices thereafter)
- I currently have a fiberglassed scratch two-stage, flown about 10 times
and 4 times so far to 10 to 15K, including Monday at LDRS to 13K
- I have 2, two-inch carbon fiber rockets (the Shocklets). Combined, they
have flown to over 20K four times on L-730's (including Saturday at LDRS)
- I have a 3-inch carbon fiber rocket, the LowCarbYen. It has flown about
a dozen times to date, including a flight to 15K on an L1080 and two
flights in the 24K range on an M2500 and an M3000, both at Wayside. I did not ask that these flights be counted as L3 attempts because I did not
consider myself to have accumulated enough experience in the hobby at the time. Obviously, these were sponsored flights.

- My 4-inch HighCarbYen has flown twice, on an L730 test flight and the
N-4000 flight.
- I also have a utility rocket, the "Bi-Polar", which flies well about
half
the time. Oh, and I also have a carbon-fibered Big Daddy, which I fly on
H's.

My failures include the two-stage shred above and a lawn dart with the
Bi-Polar. I also have lost my L1 rocket (a lake) and L2 rocket (due to a
failure of the tracking equipment).

Most of my flights in the 3 and 4-inch rockets have used GPS and almost all of my flights use radio tracking. I also own a really big pair of
binoculars. I'm sure there are many folks out there with more MD diameter and high altitude experience than I have. But I do have a fair amount of experience and my success rate is not entirely due to luck.

It should certainly be possible to repeat my flight - you just have to have
the right weather conditions and a strong rocket. I have 4 upper level
wind sites that I investigated right up to the moment of the flight. I
don't fly to high altitude if the weather isn't right, and the only reason
I was able to do it at LDRS was because of the morning high altitude slot
that Pat opened. My biggest concern was not fin flutter, but wind shear
giving effectively an angle of attack. I did an extensive (for me)
mechanical analysis of the flight conditions and fin strength to try to
estimate the conditions that I could survive. I can't summarize the
details, but take a look at my flight video. About 5 seconds into the
flight, the rocket makes a hard turn to the right. Based on the movement
of the smoke trail, which is hard to see in the smaller file I posted, I
estimate that there was a shear zone with a differential wind velocity of
about 80 mph (very rough estimate, but take a look). It wasn't supposed to be there. I estimate that this used up about a quarter of my maximum
design tolerance (the saving grace was that the rocket was moving Mach 2 at that point, which reduced the effective angle of attack). I'm reasonably sure that a rocket with any design flaws or compromises would have failed at that point.

On the visibility front, I have trouble with my eyes seeing anything over
about 3K. I can see them up to 8 or 9K with the specs. On my L3 flight,
Pat put me on the PA (via radio) to "announce" how the flight was going.
I was able to state the altitude I reached, that the apogee event had
occurred, that the descent rate was what I had predicted, the position and
altitude of the rocket as it fell, and that the main had deployed. All of
that can be proved with the gps flight file, and I would submit that I
"saw" the flight just fine.

Jim

Maybe I dont get it or am taking it wrongly But was this nessacary to post? I would appreceate it if this thread was back to the orginal topic as I felt the disscusion of this was done..

On some of the forums I belong to or admin/moderate this thread would be considered tame, but given that this forum is what it is, I have to say that the back and forth here is getting close to that thin line that nobody wants to cross.

This would be a good time to agree that people will always disagree at some point, and that it is a known and accepted occurance.

I don't see any need to continue to push each others buttons here guys, so cmon and either let the thread return to it's original topic, or let it die altogether.

This forum should *never* have to lock a thread due to good members arguing, so lets not have a big steaming pile waiting for Warren when he gets back
😉