PDA

View Full Version : Significant events in clustering and staging...


Vanel
05-04-2013, 08:46 PM
I am scheduled to give a talk on clustering and staging, and would like to include a brief history. Things like

First cluster kit (Estes Ranger?)
First two stage kit (?)
First 3 stage kit (?)
First application of new technology (solar igniters, flashbulb ignition, flash pan use, etc.)

Also anything you feel would make such a talk more interesting.

Thanks much!

stefanj
05-04-2013, 09:58 PM
You might check out the early Estes technical reports.

The multi-staging one is reprinted here:

http://www.ninfinger.org/rockets/catalogs/estes_techman/esttech.html

Clustering report from 1963:

http://www.oldrocketplans.com/pubs/Estes/estTR-6/1963_Estes_TR-6.pdf

The early Estes, Coaster, and Centuri catalogs will help you determine the "first kit" milestones. The first multi-stage kit was likely the Apogee (no "II"). Not sure if Estes or Centuri introduced the first three-stager.

Royatl
05-04-2013, 10:29 PM
early editions of The Handbook Of Model Rocketry (and probably an Olde Rocketeer column in Model Rocketry Magazine or two), talk about how the early Colorado rocketeers discovered that three motors could fit into a paper towel roll. And how Del Hitch figured out how to get three or more motors ignited in 1958. And then how Honest Ivan (a seven motor rocket) was launched (one of those Olde Rocketeer columns went into more detail about that). And how there was a standard booster with three motors where you just mounted any single stage rocket on top (by sliding its fins into slots).

All of this was probably well before the Estes Ranger.

Royatl
05-04-2013, 10:33 PM
As for Flashbulb Cluster Ignition, I was there when John Langford developed it in 1970. I think flashbulbs had been used with mercury switches and jetex wick or FSI's thermalite for igniting upper stages, but I'm fairly sure John was the first to match them up with Centuri SureShot sticks for clusters.

blackshire
05-11-2013, 08:31 AM
Don't forget parallel staging and vented gap staging, *both* of which are illustrated and discussed in G. Harry Stine's "Handbook of Model Rocketry." Vented gap staging is similar to Centuri's "Pass-port staging," except that the gap staged lower stage's vents are *never* covered, and the lower stage (which can be quite long, for scale appearance) can have its motor as much as 12" away from the upper stage's motor. Also:

Parallel staging is a special application of clustering, and it can also be combined with regular series staging (with both butt-joined and gap-staged upper stages). The Estes technical report on clustering shows a "three-motors-across" clustered booster (one or both of whose outboard tubes uses a short-delay motor that pops out a streamer, while the center motor uses a zero-delay and ignites a butt-joined second stage). In addition:

Stine's "Handbook of Model Rocketry" has a schematic-type drawing of a rather similar parallel-staged model rocket, but its short-burning side boosters "peel away" to deploy streamers or parachutes while the long-burning, central sustainer motor keeps firing to continue to accelerate the main rocket. Such a model could also have a butt-joined (or a gap-staged) series-staged upper stage that would be lit by the sustainer motor (as long as it is a zero-delay motor). Competition Model Rockets' "Marcus" strap-on parallel-staged boosters were used (among other applications) as parallel-staged boosters on Estes' two-stage (series-staged) "Sea Strike D" model. Stine's book also has a photo of Pat Artis' unusual parallel staged rocket--he placed the "peel-away" boosters (which looked like front-motored boost-gliders' motor pods) *up front* near the model's nose (to move its Center of Gravity forward), with the sustainer motor mounted in the model's tail in the usual way. And:

Royatl wrote: "And how there was a standard booster with three motors where you just mounted any single stage rocket on top (by sliding its fins into slots)."

Yes, that design (which used a cluster of three 18 mm booster motors mounted inside a paper towel tube [BT-60 size] airframe) appeared way back in the First Edition (published in 1963, if memory serves) of Stine's "Handbook of Model Rocketry." That "generic first stage" (the terms "booster" and "sustainer" are only correctly applied to parallel staged rockets, regardless of whether the booster and the sustainer are *physically* in series, as in the WAC Corporal, Aerobee, Arcon, and Iris--and I'm not saying that you made this mistake) didn't even use a stuffer tube to direct the hot particles into the upper stage's motor, if I recall correctly--that would have made for some sooty upper stages! :-)

sandman
05-11-2013, 12:12 PM
I am scheduled to give a talk on clustering and staging, and would like to include a brief history. Things like

First cluster kit (Estes Ranger?)
First two stage kit (?)
First 3 stage kit (?)
First application of new technology (solar igniters, flashbulb ignition, flash pan use, etc.)

Also anything you feel would make such a talk more interesting.

Thanks much!

As far as kits go, the first 2 stage was probably the Apogee II

http://www.spacemodeling.org/JimZ/k-05.htm

Not sure when the Centuri Black Widow came out.

http://www.spacemodeling.org/JimZ/kb-6.htm

The first 3 stage , more than likely, was the Farside.

http://www.spacemodeling.org/JimZ/k-12.htm

Chas Russell
05-11-2013, 12:24 PM
The Astron Apogee was apparently introduce in the 1963 catalog and superceded the next year by the Astron Apogee II. The Astron Farside and Farside-X were also introduced in the 1964 catalog.
AMROCS has an Omega three stager, but I only have a 1967 catalog.

This is a wonderful reference site for the Estes kits:

http://vintageestesrockets.com



Chas

Earl
05-11-2013, 01:04 PM
The Centuri Black Widow was in the '62 catalog.

The Aero-Dyne, a three stager (predecessor to the T-Bird) was in their '64 catalog and I think it might have been in the '63 catalog, but not sure (both these were just checked on on the Ninfinger site, which does not have a '63 catalog).


Earl

jeffyjeep
05-11-2013, 02:17 PM
How interesting! I'm currenty working a kit that employs both clustering and staging--the Semroc PSC Infinity.
A rear thrust ring contained 2 engine cluster in the booster, and a top thrust ring friction fit 2 engine cluster in the sustainer, PLUS since the booster "breathes" from the rear, is it considered vented staging?

mwtoelle
05-11-2013, 06:31 PM
I would not consider the PSC Infinity to have a vented booster, because you need to tape the booster/upper stage pairs together. I believe the reason for the holes in the booster centering are to lighten the weight of the booster and to help deploy the booster's streamer. The PSC Infinity flies pretty well, but the booster does not tumble, hence the included streamer. It stages pretty low with B6-0s in the booster.

Vanel
05-12-2013, 06:46 PM
Thanks for all the tips! I am currently trying to track down an answer as to when MMI first released the booster to the Aerobee and Arcon kits. Anyone know or can point me in the right direction?

I want to make sure the history of staging part of my talk is correct.

Been digging through scans of old Model Rocketeers - there is a lot of fascinating stuff there. hard to stay focused; lots of diversions

sandman
05-12-2013, 08:16 PM
Thanks for all the tips! I am currently trying to track down an answer as to when MMI first released the booster to the Aerobee and Arcon kits. Anyone know or can point me in the right direction?

I want to make sure the history of staging part of my talk is correct.

Been digging through scans of old Model Rocketeers - there is a lot of fascinating stuff there. hard to stay focused; lots of diversions

Have you been going through the DVD from NARTS?

They are very very distracting...Hard to focus! :rolleyes:

Vanel
05-13-2013, 07:33 PM
Have you been going through the DVD from NARTS?

They are very very distracting...Hard to focus! :rolleyes:

Just ordered that - been going through the CD compilation of old Model Rocketeers plus stuff I can find online. It has been a mighty interesting trip to the past! In my research, I found this page (http://www.billcooke.org/My1stRocketContest.pdf) from the July 1975 Model Rocketeer - note the 16 year old 4th place finisher under Streamer and Parachute Duration...


Crap, I'm getting old! :eek:

Gus
05-13-2013, 08:07 PM
Just ordered that - been going through the CD compilation of old Model Rocketeers plus stuff I can find online. It has been a mighty interesting trip to the past! In my research, I found this page (http://www.billcooke.org/My1stRocketContest.pdf) from the July 1975 Model Rocketeer - note the 16 year old 4th place finisher under Streamer and Parachute Duration...
Holy Cow!! You flew against Vinyard and Gassaway in a regional as a 16 year old? That was some incredibly stiff competition. Those two are still two of the best competitors around.

Vanel
05-13-2013, 08:09 PM
Holy Cow!! You flew against Vinyard and Gassaway in a regional as a 16 year old? That was some incredibly stiff competition. Those two are still two of the best competitors around.

Dumb luck :rolleyes: That was my first rocket contest, and I had almost no clue. What I did know, I gleaned from John Langford in a Georgia science camp the summer before.

Vanel
05-13-2013, 08:40 PM
My time line and notes so far - I welcome any comments/corrections/additions!


1957 - First rocket "kit" - Orville Carlisle's (NAR #1) Rock-A-Chute Mark II
(October) - 6 days after launch of Sputnik, Model Missiles, Inc (MMI) incorporated. 18x70 mm motor size created because it was same tube used by the "Buzz Bomb Helicopter" firework made by Brown Manufacturing, which produced initial rocket motors for MMI. Original Carlisle motors were ~13 mm in diameter.

"Green Mountain Proving Ground", a former WWII ammo dump, was established as MMI's launch site in late 1957. Stine refers to this as the "world's best" rocket range. Launches were held on Saturdays. It is not an exaggeration to say model rocketry was born there. Lost in April 1959 because of a dispute with a turkey farmer, who claimed that the rockets were disturbing his many thousand turkeys.

(December) - Model Missile Association established. 1st Safety Code written. Became the National Association of Rocketry at the end of 1958.

1958 - 1st 2 stage models appear at "Green Mountain Proving Ground" in first few months. MMI produces the 1st mass-produced kit, the Aerobee-Hi model rocket (April).

1959 - Vern Estes creates "Mabel" and starts manufacturing motors for MMI (Mabel could produce a motor every 5.5 seconds).

(July 16) - NARAM-1: 21 rocketeers from state of Colorado at the "Hogback Rocket Range". Available rocket motors were Type A, Type B and Type B Booster, made by Estes for Model Missiles, Inc; equivalent to A.8-3, A.8-4, B.8-4, and B.8-0. "Honest Ivan" 7 engine cluster flown just after 2 in the afternoon by Bill Meller. Norman Mains, Jr. (NAR #61) was 1st U.S. National Champion with 33 contest points.

1961 - 2 stage "Pee Wee" by Tom Rhue (NAR #50); plan only. Estes releases their first kit, the Scout. Centuri Engineering founded by Lee Piester.

1962 - Centuri Black Widow 2 stage kit

1963 - Estes 2-stage Apogee and Ranger 3 motor cluster kits, Centuri 3-stage Aero-Dyne

1964 - Estes Apogee-2 and Farside 3-stager

1965 - Parallel staging successfully demonstrated by Pat Artis at NARAM-7

1971 (April) - 1st successful demonstration of flashbulb ignition by John Langford.

1972 - Competition Model Rockets (CMR) introduces the Marcus 'strap-on booster' kit
(June) - 21 motor cluster "UPrated Igor" is successfully launched via flashbulb ignition (NGRM-3 in Atlanta)

Motor notes:

A.8-4 would be equivalent to a A4-4 in today's notation. B.8 would be B4.

1962 Centuri catalog shows the B3-0 and B3-5, roughly equivalent to a B14

Estes B14 discontinued in 1980 due to safety concerns; Centuri B14 advertised until 1981.
B8 introduced in 1980; discontinued 1997
B14 - peak thrust of 7 lbs. 0.35 sec duration; B8 - peak thrust of 5 lbs, 0.6 sec duration.
C5 introduced by Centuri in 1977; discontinued by Estes in 2001 (C5-0S went away with Centuri in 1983).
C5 peak thrust of around 5 lbs (21.8 newtons)

No "heavy lift" 18 mm BP booster since 1997.

Earl
05-13-2013, 10:00 PM
Good chronological summary.

The only thing I'd add would be that the Green Mountain site was lost, not because of the 'model' rockets, but by some amateur rocketeers who blew a hole in the farmer's fence with one of their concoctions. Somewhat minor distinction, but a distinction nonetheless.

At least, that is how I have heard the story went.


Earl

Vanel
05-13-2013, 10:08 PM
The only thing I'd add would be that the Green Mountain site was lost, not because of the 'model' rockets, but by some amateur rocketeers who blew a hole in the farmer's fence with one of their concoctions. Somewhat minor distinction, but a distinction nonetheless.

At least, that is how I have heard the story went.


Earl

The amateurs blowing a hole in the fence (which allowed livestock to escape) was the immediate precursor to the coup de grace, which was all the rockets being launched disturbing the turkeys. Both events happened about the same time, but Stine gives the honor of eviction to the turkey farmer in the MR article.

Earl
05-13-2013, 10:22 PM
The amateurs blowing a hole in the fence (which allowed livestock to escape) was the immediate precursor to the coup de grace, which was all the rockets being launched disturbing the turkeys. Both events happened about the same time, but Stine gives the honor of eviction to the turkey farmer in the MR article.

Well, I wasn't saying that it was not the farmer who threw them off the land (I've got the article too in my collection, both the original Model Rocketry article and the later Model Rocketeer article).

I was just making the point that his ire was raised initially by the illicit 'amateur' activity that had, as I recall, 'sneaked' onto the property for their activities, and hence, ruined use of the land for ALL rocketry activities.

Probably not the last time that would happen in rocketry endeavors, I don't suppose.

I tried a few years ago via Google Maps to find out what might be on that property now, but could not easily pinpoint the exact location outside of Denver. Anyone know specifically, I wonder?


Earl

Carl@Semroc
05-14-2013, 09:25 PM
Dr. Bob Craddock and I decided that this engine pair from G. Harry Stine's collection was probably used on the Mark I, making it the first two-stage model rocket. The cardboard sleeve holding the upper stage and lower stage together was built in with the two engines. Only the bottom had the usual fuse the the earliest Rock-a-chute engines had.

He would not let me separate them to see if there was delay in the bottom stage. :chuckle:

Vanel
05-14-2013, 09:45 PM
Thanks Carl! Based on this, it appears that staging goes all the way back to the beginning.

blackshire
05-15-2013, 08:15 AM
Thanks Carl! Based on this, it appears that staging goes all the way back to the beginning.Thanks to Carl seconded! That raises a staging variation (which the Europeans may have introduced many years ago) that Tim Van Milligan (Apogee Components) utilized in the 1990s with his Centrix contest models. Because their 10.5 mm motors had such tiny nozzles, the two-stage version of the Centrix was staged using a length of fuse in the second stage motor's nozzle, which was lit by the first stage motor (it was either a "dash-zero" booster motor or had a very short delay--I don't remember).

Doug Sams
05-15-2013, 10:08 AM
...the two-stage version of the Centrix was staged using a length of fuse in the second stage motor's nozzle, which was lit by the first stage motor (it was either a "dash-zero" booster motor or had a very short delay--I don't remember).As far as I know, all the 10.5mm boosters had no delay. I have a few in my stash I can check to be sure.

As for the fuses, these were wires which had been dipped in pyrogen. I have some, but have never flown them. In fact, I have been in the process of gettin' around to flying my stash of 10.5's for about 12 years now :o

I've built several birds to use them, but, alas, it seems the time has just never been right.

Doug

.

blackshire
05-15-2013, 10:16 AM
As far as I know, all the 10.5mm boosters had no delay. I have a few in my stash I can check to be sure.

As for the fuses, these were wires which had been dipped in pyrogen. I have some, but have never flown them. In fact, I have been in the process of gettin' around to flying my stash of 10.5's for about 12 years now :o

I've built several birds to use them, but, alas, it seems the time has just never been right.

Doug

.Thank you! Now that you mention it, the "staging igniters" (fuses--I never got around to building my Centrixes, and gave them and their motors to the Dade County Rocketry Association before I moved to Alaska) looked like Jetex wick and Centuri "Sure-Shot" igniters.

Carl@Semroc
05-15-2013, 11:07 AM
The Mabel I engines used Jetex Wick in the upper stage engine to aid ignition. This was dropped with the Mabel II (.5" ID) engines. I remember the "crumbly" Jetex propellant falling away, leaving just the wire hanging in some of the upper stage attempts.

Gus
05-15-2013, 11:29 PM
I routinely gap stage 10.5 mm motors, both old Apogee motors and European motors. I also routinely gap stage Estes 13 mm motors. I have done a great deal of experimentation and high speed photography and here is what I have learned. (Doug, you and I discussed this in another thread ~4 years ago but I've experimented a lot since then so this info is slightly different)

Contrary to what G. Harry thought, staging, including gap staging has little to do with flying burning particles. In standard, non-gap staging, when motors are taped together booster burn-through results in a jet of flame entering the sustainer nozzle. Ignition depends on the nature of the flame jet and, more importantly, whether the force of the tape holding the motors together is enough to overcome the pressure buildup between the booster and sustainer long enough for the jet of flame to ignite the upper motor. Booster burn-through is an inconsistent process so the jet produced is quite variable.

The top of an Estes booster motor is simply the upper end of the pressed propellant slug. If you view it from above at ultra high speed burn through may occur in the middle, or closer to an edge. It may resemble a cross burning out from the middle of where the bars cross or be more like a widening circle. The variability of this burn through is completely random resulting in very different jets being produced. A booster that burns through closer to the edge will produce a flame jet which may not be centered near the sustainer nozzle opening. As the booster continues its burn-through the flame jet widens. If the tape can hold the motors together long enough for the flame jet to reach and enter the nozzle, then sustainer ignition will occur. In most cases taped together motors do a fine job and ignition occurs.

In gap staging, the tube between the booster and sustainer motors acts like fireworks Quick Match, propgating a ball of flame from booster to the sustainer almost instantaneously. A pressure wave of gas precedes the flame by milliseconds and, if not vented out the upper sides of the tube, will push the sustainer motor off the tube before ignition occurs. But what travels up and ignites the sustainer is not little burning embers, but a ball of flame that envelops the aft end of the sustainer motor causing it to ignite. Part of the flame ball also exits the vent holes. The ball of flame is long (in milliseconds) gone before noticeable flame begins exiting the sustainer nozzle.

This is why it is possible to reliably ignite gap staged European sustainer motors with VERY tiny nozzles, without any wick. Be aware, though, that European competition 10 mm booster motors are slightly different from Estes or old Apogee motors. Euro booster motors have a forward cap with a very tiny hole in the middle. When the booster motor burns through it is only a very tiny spurt of flame that exits the top end of the motor. Euro booster motors are designed to be augmented with a pinch of black powder on top that serves as the flame propgator for sustainer ignition.

The fact that gap staging depends on a moving ball of flame, rather than burning embers, allows you to do interesting things. You can actually gap stage around gentle corners. The sustainer motor does not have to be located in a straight line directly above the booster motor. My daughter's Little Joe 1A which she flew in Slovakia used this technique to have one of the 4 18mm booster motors located at their scale outward locations in the booster to ignite a 13 mm motor in the center of the base of the Mercury capsule (to simulate the escape motor). Photo of the LJ1A internals below. This system used standard Estes motors, no augmentation. Very reliable.

Final note. Wick is useful in a sustainer nozzle when you are trying to delay ignition by a second or so. The wick fills the sustainer nozzle preventing the ball of flame from directly igniting the sustainer. Instead, the wick ignites and then takes a second or so to ignite the sustainer. Useful if you are going for altitude, but it adds a whole extra failure mode and can be tricky.

Hope this info is useful,

Steve

Gus
05-16-2013, 12:03 AM
Bill,

I know the thread is about the history of clustering and staging so I appologize for the tangent. But I want to share another photo which does a good job of showing what happens at the top of a gap stage tube, or what you would see at the top of a booster motor if it didn't have a sustainer motor taped on top.

The photo below shows three frames of a movie I did of a test trying to determine how much powder to use in a 1/8" diameter by one foot long gap stage tube for European booster motors. At the left end of the tube is an Estes igniter held in place in the tube by a tiny ball of Kleenex. I held the tube vertically and sprinkled a very tiny pinch of black powder down on top of the Kleenex.

The 3 frames are consecutive and were shot at 30 frames per second.

The first frame shows immediately before the igniter lights. Igniter and black powder to the left.

Second frame shows the small white spot at the left of the tube as the igniter lights.

Third frame shows the volume of flame at the other end of the tube 1/30th of a second later. Note the lack of flame at the left end of the tube where the igniter was.

The gap stage tube effectively works like fireworks "quick match", virtually instantaneous propogation of a ball of flame to the other end of the tube.

It's not burning embers.

Jerry Lee Lewis had it right: "Goodness gracious great balls of fire!"

Steve

Royatl
05-16-2013, 01:55 AM
My time line and notes so far - I welcome any comments/corrections/additions!




Estes B14 discontinued in 1980 due to safety concerns; Centuri B14 advertised until 1981.
B8 introduced in 1980; discontinued 1997
B14 - peak thrust of 7 lbs. 0.35 sec duration; B8 - peak thrust of 5 lbs, 0.6 sec duration.
C5 introduced by Centuri in 1977; discontinued by Estes in 2001 (C5-0S went away with Centuri in 1983).
C5 peak thrust of around 5 lbs (21.8 newtons)



My measurement of later "B14" motors show them to be almost identical to the first "B8" motors. It seems to me that this was the first example of a redesign (from drilled core to pressed core) where they attempted to keep the same designation, but then had to change (probably when the motors came up for re-certification after a three year term).

ghrocketman
05-16-2013, 01:26 PM
Somebody with a set of STONES should give MAMBY-PAMBY safety a LONG RIDE on a LARGE BOOT off a SHORT PIER and start DRILLING the core of motors to make REAL B14's on an AUTOMATED (non-manned) machine. If an 'incident' occurs, nobody is hurt and presents no real safety issue anyway. If distributed through normal 'discount' channels such as Hobby Lobby and Michaels, I would venture the B14-0 and B14-5 would out sell any other B motor except the B6-4 ! Remember Bigger (14 vs. 6 or 4) numbers ALWAYS sell better from an as-inine yet true marketing standpoint. That's why idiots randomly buy D12-7's and C6-7's when they don't know which to pick. Any way one slices it, as long as the price is competitive, the B14 will sell. Short of that even a B8 would be a VAST improvement over the engines we get now.

I still have a supply of both drilled-core and pressed-core B14's in my OOP motor supply. While the pressed-core motors do provide a pretty good liftoff punch, the drilled-core ones have a much more vigorous 'kick'. I have all flavors of the pressed-core B14 left but only have B14-0's and B14-7's with drilled-cores. Have B8's in all flavors but the Centuri-only B8-3, which I have NEVER physically seen in-person. Have seen several photos of that one that existed only one year.

blackshire
05-16-2013, 02:13 PM
Somebody with a set of STONES should give MAMBY-PAMBY safety a LONG RIDE on a LARGE BOOT off a SHORT PIER and start DRILLING the core of motors to make REAL B14's on an AUTOMATED (non-manned) machine. If an 'incident' occurs, nobody is hurt and presents no real safety issue anyway. If distributed through normal 'discount' channels such as Hobby Lobby and Michaels, I would venture the B14-0 and B14-5 would out sell any other B motor except the B6-4 ! Remember Bigger (14 vs. 6 or 4) numbers ALWAYS sell better from an as-inine yet true marketing standpoint. That's why idiots randomly buy D12-7's and C6-7's when they don't know which to pick. Any way one slices it, as long as the price is competitive, the B14 will sell. Short of that even a B8 would be a VAST improvement over the engines we get now.I've seen it (and heard it, via conversations in hobby shops) happen--"This one's better, it's a 'see-six-SEVEN!'--while they were buying an accompanying rocket kit that required shorter-delay motors...I still have a supply of both drilled-core and pressed-core B14's in my OOP motor supply. While the pressed-core motors do provide a pretty good liftoff punch, the drilled-core ones have a much more vigorous 'kick'. I have all flavors of the pressed-core B14 left but only have B14-0's and B14-7's with drilled-cores. Have B8's in all flavors but the Centuri-only B8-3, which I have NEVER physically seen in-person. Have seen several photos of that one that existed only one year.Although I can't speak for him, of course, there is a potential future supplier for such motors. John Wickman, the President of Wickman Spacecraft & Propulsion Company, is a former Aerojet engineer. He and Hermann Oberth's son developed a new, low-cost solid propellant that uses phase-stabilized ammonium nitrate, and he teaches amateur rocketry courses and sells publications on making these rocket motors (see: http://www.space-rockets.com/ ). Unlike G. Harry Stine, who categorically stated "There is no safe way to make a rocket motor of any type," Mr. Wickman counters (and has demonstrated numerous times, through his motor-making courses) that anyone who takes prudent safety precautions can make his or her own successful--and reliable--rocket motors (his students static fire and flight test their motors as the "final exam").

Doug Sams
05-16-2013, 02:29 PM
Euro booster motors are designed to be augmented with a pinch of black powder on top that serves as the flame propagator for sustainer ignition.While I haven't yet adulterated any motors, it's on my radarscope for some future projects, as discussed in other threads here, often with Ted Macklin in the game plan :)

Anyway, I usually pre-emptively scrape the nozzles of my sustainer motors using an appropriately sized drill bit. I suspect this results in a small amount of BP dust being left behind in the nozzle which enhances the ignition process. At least, that's my theory.

The dust is in the nozzle, and not in the booster, but it's otherwise similar to what is described.

Dust particles have the benefit of increased surface exposure (ala grain elevator explosions) and thus only a tiny bit of flame is necessary to light them up.

Doug

.

Doug Sams
05-16-2013, 02:35 PM
My measurement of later "B14" motors show them to be almost identical to the first "B8" motors. It seems to me that this was the first example of a redesign (from drilled core to pressed core) where they attempted to keep the same designation, but then had to change (probably when the motors came up for re-certification after a three year term).Yes, and my pics and measurements support this. Later B14's appear to have the same, smaller diameter nozzle of the B8's, altho they were still deeper cored like the B14's. In the pic below, the last number is the measured nozzle/core depth. Doug .

http://www.doug79.com/motors/B14-vs-B8-3.jpg



.

Doug Sams
05-16-2013, 02:38 PM
Final note. Wick is useful in a sustainer nozzle when you are trying to delay ignition by a second or so. The wick fills the sustainer nozzle preventing the ball of flame from directly igniting the sustainer. Instead, the wick ignites and then takes a second or so to ignite the sustainer. Useful if you are going for altitude, but it adds a whole extra failure mode and can be tricky.So you're saying I'd be better off forgoing the staging ignitor when (if) I ever finally get around to using my A2 and B2 sustainers? :):o

Doug

.

Gus
05-16-2013, 08:29 PM
So you're saying I'd be better off forgoing the staging ignitor when (if) I ever finally get around to using my A2 and B2 sustainers? :)

.Doug,

I've never found it necessary to use a staging igniter. To give you an idea of how tiny the sustainter nozzles are we are igniting, look at the photo below. An Estes A10 nozzle is the Grand Canyon compared to a Delta A1. And the amount of flame produced by a standard Estes booster is just huge compared to what you get from a pinch of black powder (see previous pic).

As for scraping out the sustainer nozzle, I know a lot of folks do it, and some of my teammates think not doing so borders on lack of patriotism :), but I've never found it necessary. My fear is that I will inadvertantly scrape a smidgen out of the clay nozzle itself, leading to off-center thrust. Probably not a realistic fear on Estes-sized nozzles but more probable on a Delta or Ultra.

Vanel
05-16-2013, 08:35 PM
Steve,

My talk will also include mention of various staging/clustering techniques, so you are not off topic at all! I very much appreciate the information...

GH,

I was wondering when you were going to weigh in. Hard to imagine you not commenting on any thread that includes mention of the B14 :D

However, I do agree with you in that I miss those motors. A proper 18mm 3 stager is almost impossible without them.

ghrocketman
05-17-2013, 09:15 AM
Vanel-
I had some comments above about the B14/B8....

On a nearly windless day, one could get away with a C6-0 to C6-0 to C6-7 flight in an astron Farside, but I would not try it with a Farside-X.
Of course if the C5-0 still existed it would also be acceptable along with the B14 or B8 in the bottom stage of a 3-stager. The old 18mm Cox D8-0 was good too.

If I was to build an Astron Farside now, I would just leave the first stage booster 24mm and use C11-0's or D12-0's in it.

I used to like to fly my Old Astron Avenger on an A8-0 or B6-0 to B14-5 or B14-7 flight. Would liftoff slow and stage low, then crazily take off like a shot when the B14 ignited.
Was neat for school demos too.

Gus
05-18-2013, 01:01 AM
...I used to like to fly my Old Astron Avenger on an A8-0 or B6-0 to B14-5 or B14-7 flight. Would liftoff slow and stage low, then crazily take off like a shot when the B14 ignited.
Was neat for school demos too.
GH,

Thanks for that nice explanation. I could never figure out what anyone would use a B14-7 for. Makes sense, and sounds fun.

Steve

Randy
05-18-2013, 09:39 AM
(July 16) - NARAM-1: 21 rocketeers from state of Colorado at the "Hogback Rocket Range". Available rocket motors were Type A, Type B and Type B Booster, made by Estes for Model Missiles, Inc; equivalent to A.8-3, A.8-4, B.8-4, and B.8-0. "Honest Ivan" 7 engine cluster flown just after 2 in the afternoon by Bill Meller. Norman Mains, Jr. (NAR #61) was 1st U.S. National Champion with 33 contest points.

1961 - 2 stage "Pee Wee" by Tom Rhue (NAR #50); plan only. Estes releases their first kit, the Scout. Centuri Engineering founded by Lee Piester.

1962 - Centuri Black Widow 2 stage kit

1963 - Estes 2-stage Apogee and Ranger 3 motor cluster kits, Centuri 3-stage Aero-Dyne

1964 - Estes Apogee-2 and Farside 3-stager

1965 - Parallel staging successfully demonstrated by Pat Artis at NARAM-7

1971 (April) - 1st successful demonstration of flashbulb ignition by John Langford.

1972 - Competition Model Rockets (CMR) introduces the Marcus 'strap-on booster' kit
(June) - 21 motor cluster "UPrated Igor" is successfully launched via flashbulb ignition (NGRM-3 in Atlanta)

Motor notes:

A.8-4 would be equivalent to a A4-4 in today's notation. B.8 would be B4.

1962 Centuri catalog shows the B3-0 and B3-5, roughly equivalent to a B14
No "heavy lift" 18 mm BP booster since 1997.


Bill,

Impressive list.

Any listings for the first date and person to gap stage 5 to 5 to 1 over 10.5 inches twice on the same flight? Does it HAVE to be at a NAR NARAM launch to count in the record books? I think Verna made her first successful 5-5-1 flight back in 2004 (I think) but I would have to dig to get an exact date. I do know it's been done since by someone at a NARAM, I think the following year or maybe 2.

Her first successful Saturn V 5-5-1 flight was at the BRB field in Birmingham on a Tuesday or Wednesday afternoon and was witnessed by then NAR 665 pesident Ron Witherspoon, and me & my son. Like I said I may be able to come up with the exact date. We just never thought about getting some kind of official recognition for it. The actual liftoff photo is on our site on the Bad Girl page.

Randy
www.vernarockets.com

Vanel
05-18-2013, 09:26 PM
Hi Randy!

There are statements about large staged clusters, but nothing very specific as to date/launch. However, I am sure that there were staged clusters with a fair number of motors by the mid-70's, especially with the advent of flashbulb ignition. The staging of Saturns was discussed in at least two MR/AS articles starting with Gary Cole's article in the Dec 1976 MR issue; also Bill Dye's article in American Spacemodeling, July 1986. It also featured a 5 motor cluster in the 1st stage.

I am very impressed by Verna's accomplishment - I have never built or flown a model with a clustered 1st and 2nd stage, much less a Saturn. I wish I had seen it launch!

Randy
05-19-2013, 08:26 AM
Bill,

Thanks for the reply. As always I should have asked Verna if she had any notes. She used parts from 2 different 2157 kits over the 4 flights, mostly the flimsy fins. If she did it again she'd use the Sirius resin fins on the first stage.


Flight results notes from her notebook 4 flights total:

4-27-04 All engines of 1st stage - free fall but no damage. Got 2 of 2nd stage, 1 of the 2 chutes brought it down nicely. 3rd stage seperated from the burn thru but did not light. Slight damage to 3rd stage paper wrap. Easily repaired. Slight damage to 3 of the vaccuform fins, easily repaired. Flown at strip mine in north Jefferson County, just us.

9-4-04 All 5 first stage, all 5 2nd stage - nice kick at staging but still missed 3 rd stage engine again and no chute. 3rd stage vaporized on impact,. Repaired 2 fins of first stage. Flown at BRB 665 field in North B'ham with our son and Ron Witherspoon.

11-17-04 All 5 of 1st and 2nd stage recovered no damage. GOT the 3rd stage this time! Very long walk to recover. Drifted almost to the north tree line about 600 yards. NO Damage! She credits complete success to using slightly more Scotch between 2nd & 3rd stages. 100 % success! Witnessed by Ron Witherspoon and our son.

3-12-05 All 5 of 1st stage, 4 of the 2nd stage but missed core engine so 3 rd stage no chance to light. Recovered missing 2 fins of the 1st stage, second stage drifted down nicely no damage. 3rd stage tumble deployed the chute, no damage. Witnessed by Ron Witherspoon.

Rocket repaired for static display.


So it took 3 attempts to get it right once but she did get it. It sits ready to go right now, but I doubt she'll ever fly if again. She would tell you that "itch" has been scratched. Maybe if one of the grandkids asked her... she might. ; )

Randy
www.vernarockets.com

Earl
05-19-2013, 12:17 PM
Randy-

Do you recall the motors used in each stage? I assume 18mm BP of some type, but would be interested to know which, if you/she remembers.

I've done clustered five engine AP/BP single stage Saturn V flights and have long wanted to do a 'full up' Saturn V three stage flight......just never got it 'on the books' to try yet.


Thanks,

Earl

Randy
05-19-2013, 04:28 PM
Earl,

After a considerable development and research process was added to her own experiences, on the 100% successful launch she decided to go with:

1st stage 4 C6-0 & 1 D12-0
2nd stage 4 B4-2 & 1 B6-0
3rd stage 1 B4-4

The D12-0 & B6-0's were the core engines.

Her build, with photos and some narrative, is posted to the SEARS 572 website. http://www.sears572.com/supersaturnv.htm

Scroll the pages and follow the links at the bottom to see all 7 pages and the flight report to that date.

Randy
www.vernarockets.com

Gus
05-20-2013, 03:16 AM
Randy,

You indicate there was a 100% successful flight, but it is not covered in the flight report. Was Verna really able to gap stage 5 motors at once (1st to 2nd stage) and get all 5 second stage motors to ignite?

Steve

Earl
05-20-2013, 09:09 AM
I routinely gap stage 10.5 mm motors, both old Apogee motors and European motors. I also routinely gap stage Estes 13 mm motors. I have done a great deal of experimentation and high speed photography and here is what I have learned. (Doug, you and I discussed this in another thread ~4 years ago but I've experimented a lot since then so this info is slightly different)

Contrary to what G. Harry thought, staging, including gap staging has little to do with flying burning particles. In standard, non-gap staging, when motors are taped together booster burn-through results in a jet of flame entering the sustainer nozzle. Ignition depends on the nature of the flame jet and, more importantly, whether the force of the tape holding the motors together is enough to overcome the pressure buildup between the booster and sustainer long enough for the jet of flame to ignite the upper motor. Booster burn-through is an inconsistent process so the jet produced is quite variable.

The top of an Estes booster motor is simply the upper end of the pressed propellant slug. If you view it from above at ultra high speed burn through may occur in the middle, or closer to an edge. It may resemble a cross burning out from the middle of where the bars cross or be more like a widening circle. The variability of this burn through is completely random resulting in very different jets being produced. A booster that burns through closer to the edge will produce a flame jet which may not be centered near the sustainer nozzle opening. As the booster continues its burn-through the flame jet widens. If the tape can hold the motors together long enough for the flame jet to reach and enter the nozzle, then sustainer ignition will occur. In most cases taped together motors do a fine job and ignition occurs.

In gap staging, the tube between the booster and sustainer motors acts like fireworks Quick Match, propgating a ball of flame from booster to the sustainer almost instantaneously. A pressure wave of gas precedes the flame by milliseconds and, if not vented out the upper sides of the tube, will push the sustainer motor off the tube before ignition occurs. But what travels up and ignites the sustainer is not little burning embers, but a ball of flame that envelops the aft end of the sustainer motor causing it to ignite. Part of the flame ball also exits the vent holes. The ball of flame is long (in milliseconds) gone before noticeable flame begins exiting the sustainer nozzle.

This is why it is possible to reliably ignite gap staged European sustainer motors with VERY tiny nozzles, without any wick. Be aware, though, that European competition 10 mm booster motors are slightly different from Estes or old Apogee motors. Euro booster motors have a forward cap with a very tiny hole in the middle. When the booster motor burns through it is only a very tiny spurt of flame that exits the top end of the motor. Euro booster motors are designed to be augmented with a pinch of black powder on top that serves as the flame propgator for sustainer ignition.

The fact that gap staging depends on a moving ball of flame, rather than burning embers, allows you to do interesting things. You can actually gap stage around gentle corners. The sustainer motor does not have to be located in a straight line directly above the booster motor. My daughter's Little Joe 1A which she flew in Slovakia used this technique to have one of the 4 18mm booster motors located at their scale outward locations in the booster to ignite a 13 mm motor in the center of the base of the Mercury capsule (to simulate the escape motor). Photo of the LJ1A internals below. This system used standard Estes motors, no augmentation. Very reliable.

Final note. Wick is useful in a sustainer nozzle when you are trying to delay ignition by a second or so. The wick fills the sustainer nozzle preventing the ball of flame from directly igniting the sustainer. Instead, the wick ignites and then takes a second or so to ignite the sustainer. Useful if you are going for altitude, but it adds a whole extra failure mode and can be tricky.

Hope this info is useful,

Steve

Steve-

Interesting info. Sounds like the basis for a good tech article for Tom Beach to run in Sport Rocketry mag. I'm sure many would find it enlightening.

Earl

ghrocketman
05-20-2013, 09:58 AM
I would tend to believe that top stage needed a B4-6 or B6-6 instead of a B4-4 !

Randy
05-20-2013, 11:32 AM
Gus,

She made 4 flights in all. Look back on this thread for the flights and dates. There were two attempts prior to the successful flight. The report on the SEARS website was about the April 2004 attempt and the build article was posted in May of 2004. The article there has not been updated since the original posting, 9 years ago.

Yes. Her 3rd flight was indeed 100% successful -- and came after the build article on November 17, 2004 - 6 months after the report that goes with the 7 page build was posted by SEARS president Greg Lane. In addition to Verna & I, the flight was witnessed by our club president at that time, Ron Witherspoon and my son.

Because the build article had already been posted to the SEARS 572 website, SR was not interested in an expanded article on her Saturns. There's a rule or something about any part of an article and previous postings but - Verna and her Saturns were featured in a brief article I did on another topic for SR that appeared April 2006 and it featured her and her Saturn V's .

Randy
www.vernarockets.com

Gus
05-20-2013, 04:18 PM
Randy,

I fly gap staged rockets more than almost anyone else I know. Simultaneously igniting 5 clustered gap-staged motors is a truly spectacular accomplishment! I've seen lots of multi-staged Saturn V's fly, but they all used electronics. Honestly, it never occurred to me that "going native" was possible.

I remember reading about Verna's Saturn a long time ago, long before I started gap-staging, so I wouldn't have truly understood how amazing it was.

I'm particularly intrigued that she got the D12 and C6's to work in harmony. The C6s actually burn slightly longer than the D12 so I would have thought the central motor in the second stage would have lit before the outboards. I also would have thought the likelihood of 1st and second stage torquing and preventing separation would have been really great.

Can you tell us what the failure modes were on the first two flights?

Again, thanks for sharing this. You just really expanded my envelope of what is possible.

I love this hobby.

Steve

Randy
05-20-2013, 07:10 PM
Steve,

Back up just a bit to post 40 of this thread where I typed up some of her notes; for some detail on all 4 flights.

Obviously you've got some good experience from your flights, as your last post on flight characteristics are very close to what we saw on her flights. The engine burn through times are miliseconds apart for the boosters but there is a small difference. On the first flight they were obvious, not as much so on the 3 that followed. There was mild torquing on all 4 but not enough to spoil the flights.

The thing I found the most interesting was what she took away from each attempt as to why things went the way they did and how she decided to adjust the next attempt. I think it was mainly the difference in how women think and the way men think. We often came to the same conclusions but differed on how to adjust. Her rocket/her choice.

Part of her adjustment was to use engines with the largest nozzles in the 2nd & 3rd stage, hence her selection and visual observations of what she was holding at the time. What we found VERY interesting in our motor selection and research was that there can be a big difference in diameter between nozzles of the same designation. Was it a screw up at the factory? We don't know but when they were used, they performed the same. Most lilkely every old timer here will say "It's not possible" but I'm telling you we saw it and in actual use.

I do not recall the exact engine so just for an example, say you had 5-6 packs of B6-0's. Upon inspection, you see all engines in each pack are the same, but when compared to another pack from another batch, the nozzles of pack #2 are easily larger in diameter, at least on the exterior surface. They look and perform identical in every way but one pack seems to have at least a 50% larger opening. I even took a photo and posted it for comment someplace, maybe RMR when it was still fucntional, I don't remember, definately not YORF or TRF. Almost had to be RMR/ABMR.

Maybe Jerry can shed some light on how to get the same thrust profile on 2 different engine nozzles.

Again, the torque factor was nominal but there was a definate change in angle after staging. The flights that were not successful mainly came down to simply missing a core motor all 3 times.

Verna would tell you the one that worked had the largest nozzles she could use, double the tape where they mate (about 1/2" wide by 1.5" long) 4 places spaced equally around the bt. (Lots of venting going on too) But she also said that when everything is perfectly built and the conditions are optimal there is still one major factor in being successful and that is LUCK!

Once I reminded her of what Bear Bryant and Knute Rockney used to say: "Luck is when preparedness, meets opportunity, so it tales your best effort and then a little help from God, Karma or whatever you happen to believe in. In this case she said she had some help from CHAD. ; )

With all said and done she feels that even in the best case senario it's still a 50/50 shot but when it works, it's truly amazing and satisfying.

Oh, one last thing, perhaps what sets her accomplishment apart from all the others, is that she didn't use electronics. She decided before she broke open the box that she wanted to do it old school.

Randy
www.vernarockets.com

modeltrains
05-20-2013, 08:29 PM
Looking at thread title "Significant events in clustering" and keep thinking that Gunnery St. Highway might have a different take on the mental image created.

ghrocketman
05-21-2013, 10:59 AM
Gy.Sgt. R. Lee Ermey would most likely be of the same opinion as Gunny Highway and he is a REAL Gy. Sgt.