ANNOUNCING NARAM-46

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Well I do not know what it is technically called. I understand it and can explain it to a point but do not know the "terms" that properly describe it so I chose soemething that seemed kind of close. that is why I worded it the way I did.

I am speaking of the visual effect not the technical effect. mathmatically they are all the same and can be calculated. Visually you see to visually distinct and different things. Watch an alpha go up and watch a Centuri Saucer go up. 2 distinctly different flight profiles even though the same mathmatical formula can predict the information for both flights.

I do not know the technical optimal so I just used the "experienced" doable.

Incorrect this is almsot always true in reality. MOST PEOPLE do not FLY E RCRC's On E6's. Most people do NOT FLY RCRG's period.

Most people fly rockets where almost all of their altitude is aquired on the COAST phase of the flight coast phase including any long trail off of the thrust phase.

Again two visual distinct and different flight profiles that are both mathmatically the same.

I am speaking from the visual aspect. for your sake I will put it into percentages for you.

Let go extreme just to get the idea across.

Normal rocket go for 1% and coast for 99%

My Rockets tend to go for 99% and coast for 1%

the math is the same for both the VISUAL distinction is very different. NO the percentages are not mathmatically accurate I am just using them to make the point.

MOST of the altitude gained by a snitch it under thrust. EVEN with a B6-2 it will be pointing DOWN then that ejection charge fires.

On drag limited models that I speak of when the motor burns out the vertical part of the flight is "basically" over. so the longer the BURN the Higher the flight.

Chris Taylor

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Reply to
Chris Taylor Jr
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I don't remember seeing any airfoil at all. Chris??? George?

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

Good comparison data points. WOuld you fly a 12# glider on a new I154? How about a cluster of 2 H motors with about the same average thrust?

They were that thick, and IIRC not airfoiled at all.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

QED.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

Perhaps you're using digital motors instead of analog motors :-)

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Reply to
Bob Kaplow

ROFL

I recall when I first went into the Claremont Rocket Society building (yes an entire building) in about 1966 there was a poster on the wall showing the relative drags of a wire cross-section, a plate cross section and an airfoil cross section.

The wing shape must have been 50 times the cross-sectional area as the wire and the flat plate was not much bigger than the wire.

This IMAGE has always since motivated my to airfoil EVERYTHING. My preferred fin airfoil these days is a 2:1 ogive for simplicity and strength, but airfoiled, EVERYTTGING is.

Jerry

This should be in the FAQ.

"Do or do not, there is no try." - Yoda

Reply to
Jerry Irvine

Is a chuffy motor digital?

Is a buttkicker digital?

JERRY

Reply to
Jerry Irvine

Thats not too bad, just rounding the edges is sufficient as long as you have good stiffness (some play but not much) across the span. Ive used a piece of

1/4" x 4 x 36 basswood across each side of a wing, that helped a LOT, and not much of a wt addition once youre gonna sit over 10lbs anyways.

Well, something like an I200ish then, if you are gonna be 10lbs-ish.

Why would you even need to control it on the way up?? IMHO any glider over

5lbs or H+ should be a foolproof hands off boost, unless you have the RC skill that yourself or GCG does. But even the best RCers sometimes get a 'funny boost event', and a hands off rocket boost prevents that. Save the theatrics for the way down!

Oh great, now GCG is gonna see this and *have* to make something ridiculous (he he) and wait to fly it at a 44.99999* angle when 'you know who' is RSO at the next NARAM, and whip butt in battery dura...er, EGG duration. Preferably with a three F10 cluster 8^)

OH, you must be referring to my 'thanks for the WRONG reload in the H128 bag, AT!' flight. Yea, this was actually an H238, one of the olllllld ones, with the different original delay setup. Still flew well but scary.

J90 in a retrofitted Astron SST pod did this, it was 7.5lbs liftoff. Man, did that thing goooooooo forever!! Never got to try a K185 tho, still might do a hybrid version of this if I get my butt back in.

Either way, Ill bet Grrrr v2 will 'rool and drool'. Maybe someday Ill get to see it....

AstronMike

Reply to
Mike Lee Kochel

Thanks. Was nice being able in infer 'this motor worked for this wt, how bout this?' whilst flying these things back then. Seemed AT had a looooot of H and I 'glider motors' then, and theres even more variety now, right?

No, unless......

1/ It was intended to be a 45* or 60* flight from the get go, and.... 2/ I had known good RC equipment AND the xp to be able to control it during boost. Well, I dont have either, so that left me out. 3/ Id flown a similar glider before, slightly smaller. To use your I154/12lb example, how about a G35/4lb glider? Hey Chris, you done a Grrr JV? Also, isnt Robs biggest glider right on this spec? HE is the one who will tell you definitively what you should/ shouldnt do.

Two H100ishes, yea, thats better.

AstronMike

Reply to
Mike Lee Kochel

I agree with you on airfoiling. I was at CP&H and they had an Estes Yankee marked for 99 cents. Only one on the wall. I bought it, put an ogive nosecone on it and airfoiled even _that_ minuscule little thing. I tried to use it for the NARTREK PD and never saw it again :) I hope some kid found it and gave it a good home. I even airfoil the fins on all my Saucers that incorporate them. Great fun.

The point is that Yoda was right!

Patrick

Reply to
IceAge

All that $#!+ we had to listen to last year about bad motors, old motors and the whole works and he did not even airfoil the wings?

Reply to
GCGassaway

Aerodynamics matters?

? It was a very thin cross section (an inch or

A true airfoil would have provided 10 times the lift with about the same mass.

It was that way for MANUFACTURING REASONS NOT EFFICIENCY REASONS.

I have a suggestion. Change that and be shocked how well it flies.

Justifying bad choices does not make them right. It only increases "suspended disbelief" they are wrong from the beginning. You sir should chat with your peer Chuck Rogers.

Jerry

"Our enemies are never villains in their own eyes, but that does not make them less dangerous. Appeasement, however, nearly always makes them more so."

- Don Dixon

"Jerry's practical approach has a lot going for it."

- Wolfram V. Kiparski

"Life is short and the path is often unclear. It is a great sin to knowingly contribute to someone's confusion."

- anon

Reply to
Jerry Irvine

I would suggest that you read the Project X-30 article by Dave Schaefer in Sport Rocketry, and compare it with your own efforts. They seem to have "the right suff", while you have the wrong stuff. Learn more, laugh less.

Alan

Reply to
Alan Jones

That would be cool as heck, looong and slow.

Georgespeak for 'its only gonna stay up 15 mins with two eggs instead of

22+'...

He he you just cant change him can ya? Let him join Southern Cruetron just to fly superroc events.

AstronMike

Reply to
Mike Lee Kochel

Exactly. I understand many things I just do not have the "technical" terms to ascribe to them so I pick the words that most closely resemble what I am talking about.

some people like to take that as free liscience to blather on. but it does not change that I am right and they are wrong.

I can demonstrate it 100 times predictably the same way every time.

mathmatically

Reply to
Chris Taylor Jr

incorrect. the benifit gained from airfoiling an 11ft by 6ft delta on a

12pound model that is going to have airtime less than 1 minute anyway is simply not only pointless and ineffecient but outright STUPID.

you would waste DOZENS of hours for what benifit ? 3 extra seconds of glide and 10 extra feet of boost ?

if you want to be stupid enough to try it GO AHEAD. I will PAY your naram fee to sport fly next year if you build one an attend and we will have a fly off.

How about it. put your money where your mouth is ?

Reply to
Chris Taylor Jr

Here is one better jerry and bob. you guys build a grr to my specs with an airfoild wing.

I will GIVE you the reciever and servos I used and let you borrow my radio and jerry I will still pay your naram sport fliers fee. if you guys build it and show up with it at naram.

How about it. now all you have to buy is the foam and the building supplies. all the electronics will be supplied.

Put your money where you mouth is ?

Chris Taylor

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Reply to
Chris Taylor Jr

snip whining and personal attack

yep

snip more false attacks.

Reply to
Jerry Irvine

One of my proposals to the BoT was to adopt the 125g unified propellant limit I origonally proposed circa 1984-5.

That would allow the equivelent of a RMS 29-240 motor.

So did it pass? :)

Jerry

Reply to
Jerry Irvine

your right. I do not care. even if george cared it would not change that I do not care.

the GAIN by airfoiling the wing on this type of model is so absolutely tiny and miniscule compared to the INSANELY HUGE amount of work it would add that it is literally stupid to concern myself with it.

Reply to
Chris Taylor Jr

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