Discussion in 'LDRS Questions & Answers' started by JonathanOtt, Aug 14, 2018.
What is LDRS?
Irony.. When a group dedicated to making rocketry safe names their signature event "Large Dangerous Rocket Ships".
When you just google LDRS, nothing rocketry comes up in the first couple pages (on my browser anyway... of 580,000 hits)
Name goes back many years............
LDRS quite simply is the national annual high power rocket launch in the U.S. hosted by one (or more) of Tripoli Rocketry Association's member prefectures.
Those words that the letters represent are just that. Words.
What you need to know is the event is high power rocketry and fun.
And if anyone wants to see a well run LDRS, get yourself to LDRS 38 in Argonia, KS next year.
Every year I hear people who are concerned about the name “Large Dangerous Rocket Ships”. As so well told by Chris Pearson, the name was initially a tongue-in-cheek reference to how motors exceeding the E and F and the rockets they could carry were viewed by orthodox model rocket flyers.
The hobby shop I go to for plastic models used to have a guy there who thought D motors were HUGE. They don't have any rocketry stuff these days and I haven't seen that guy in quite a while. He was having health issues a few years ago; his eyes. Man, did I get an earful about that the one time I went in there. He just went on and on and on; and then he apologized for doing it - sort of. You don't get service like that at Wal-Mart.
Lose Dollars Really Soon
What is LDRS?....My goal for next year. (I hope it's on the East Coast.)
Umm. Argonia next year.
Crap! I had it confused with the upcoming Airfest. Well....looks like I need to convince my wife I need a trip to Kansas in 2019.
Tell her I said it's ok.
Let's Do Rockets Safely!
Tell her you have the urge to go to a flat, featureless, seemingly never-ending landscape; its Mars or Kansas, her choice.
That flat, featureless, seemingly never-ending landscape you refer to we call recovery area. With that in mind it’s certainly not a bad thing!
It’s only a safe hobby because of the respect and precautions taken for how dangerous they can be.
Is it possible to go there next year with my 10 year old son? We want to look at the launches of really big rockets. Are there any age limits for viewers?
Spectators of any age are welcome. It might be a bit overwhelming, there will be hundreds of fliers and possibly a thousand spectators next year. The Kloudbusters put on a great launch, and have done LDRS many times before.
Thank you, Wayco. I'll plan a vacation for the time of the event.
Tomahawk, there are high power rockets flying somewhere almost every weekend. You can probably find a launch in California sometime within the next month.
Yes. There's a launch planned at our Holtville launch site on October 6. http://www.tripolisandiego.org/ The rockets probably won't be as large as at LDRS, but it's a much shorter drive.
There's a launch this weekend at Lucerne. https://rocstock.org/
Here is the history of LDRS ( PDF below )
The LDRS Story
(Originally appearing in SNOAR News, and reprinted in the Tripolitan. It is reprinted
here as an updated version.)
By Christopher T. Pearson
The story of the first organized national high power sport launch, the first to get a FAA
waiver, and the first to cause the NAR to expel members.
About the author: He got started in model rocketry in 1967, at the tender age of 13 years
old while the US and the USSR were at the height of the Moon race,. By 1976, at the ripe
old age of 22, he was ready for something more than NAR competition and Estes’ rocket
kits. Having been introduced to motors “bigger than a D” by Flight Systems Inc., he
entered the forbidden (at least as defined by the NAR) realm of what was called “illegal
amateur rocketry”, that was, at the time, anything weighting more than one pound and
having more than four ounces of propellant. Clusters of D, E and F black powder motors
soon gave way to early composites. Reinforced Estes and Centuri model rocket kits
adapted to take high-power motors quickly evolved into what was considered “big” for
the time, four inch diameter rockets of original design and later those produced by the
first high-power rocket kit companies. The rest is history.
The LDRS story actually got started a number of years before the first LDRS was held in
a northern Ohio farm field. Here’s how it began:
As with many people, I started into model rocketry as a teenager, but more adult things,
like cars, motorcycles, girls, a job and college forced me to put rocketry on the back burner
for a while. When I got back into rocketry, even though I was heavily involved in
NAR competition until 1978, I wanted to try something different. I got started in high power
rocketry, as it existed then, back in 1976. I quickly made contacts with people all
over the country that were involved in the emerging high-power hobby. Some of these
people were Gary Rosenfield (then of Pro-Jet, predecessor of Composite Dynamics and
Aerotech), Roger Johnson (aka: The Rocket Clown), Korey (the Ace from Space) Kline
of Ace Rockets, the first high power rocket kit company, Mark Mahyle of Small Rocket
Sounding Systems, another composite motor and kit company, along with others who
were, at the time, taking “model rocket technology” to the limits. MRT, as it was also
called, referred to high-power rockets made from model rocket components.
Between 1972 and 1978, unless you had an “in” with a motor manufacturer, about the
only thing there was for the high power crowd was either clustering D12's or using FSI
motors. Centuri/Enerjet had ceased motor production, although limited motors were still
available and being used. This was before any of the early composite rocket motor
companies arrived on the scene. Some of the people that were visible in the early high
power community were Scott Dixon of Vulcan Systems, and Irv Waite, formerly of
Rocket Development Company, father of the Enerjet line of composite rocket motors.
They were both producing professional rocket motors for military and industrial use, but
for the right amount of $$$, they could be persuades to make motors for you.
Before this time, there were many notable, and now very rare and collectable, high power
rocket motors. Pro-Dyne, maker of F thru G class motors. Coaster, who made large E, F
and G black powder motors, and Centuri Mini-Max, also D, E, and F black
powder motors. They had all vanished from the rocketry scene by 1970. Gary Rosenfield
was one of the new breed of composite motor manufacturers, as his first company, Pro-
Jet, produced F and G composite motors. Mark Mahyle of SSRS (later known as
Crown Rocket Technology) entered the foray with E thru H composites motors, and a
little known company called Plasmajet, run by John Krell and Randy Sobczak, made F
thru I motors. So with those new motor manufacturers producing a new generation of
motors, a number of high-power kit manufacturers soon followed suit. Unfortunately, as
with most hobby-type businesses, many people entered the hobby and left just as quickly.
Gary Rosenfield joined forces with John Davis and formed Composite Dynamics, which
gave rocketry mass-marketed composite 24mm E and F motors, as well as the first end-burning
composite, the 29mm E9, a motor which, ten years earlier, Enerjet had called
“impossible”. Other early companies produced specialized items for the high-power
community such as launchers, pads, etc.
Unbeknownst to the NAR, a number of people at the time were flying high-power rockets
at local sport launches or side by side with competition rockets at NAR events. Unlike
NARAM’s today, where the sport range is busier than the competition range, sport flying
was almost unheard of at a NAR launch. At one of our regional meets early in 1980,
several uncertified F, G and H motors were flown in overweight rockets. Somehow,
word of this leaked out and later that year while at NARAM-22, another SNOAR
member and I were called on the carpet by Mark Bundick, the National Contest Board
Chairman and questioned about it. This is where the famous, "Who flew the G?" quote
My high-power contacts in California told me of all the extreme rocket flying that was
happening out there: huge clusters of F and G motors, real metal vehicles, special effects
rockets and so on. I wanted to observe what was going on in high-power rocketry on the
west coast, so, in 1981; I journeyed to Smoke Creek, Nevada, to attend the annual
Memorial Day Amateur Rocket Launch. This was sponsored by the Rocket Research
Institute, and is primarily for the zinc/sulphur crowd, but they allowed the launching of
large model rockets and MRT vehicles, along with a lot of professional pyrotechnics
people who lit up the nighttime sky with fireworks demonstrations. While there, I heard
Roger Johnson say something that was to stay with me long after the launch, and that was
“We’re going to fly some large and dangerous rocket ships!”
To tell you the truth, I was actually somewhat disappointed by what I saw flying out at
Smoke Creek. Except for the zinc/sulfur and asphalt/perchlorate rockets being flown
by Dr. Key’s high school group, it was rather mundane. It was nothing like what is flown
at LDRS today. Primarily a lot of four-inch stuff with clusters of F and G motors, and an
occasional H or I motor. And as for the launch facilities, you walked out away from the
cars, stuck a rod in the desert floor and ignited the motors with fuse and a match!
Nothing like I was led to believe was flown.
Later that summer, the NAR section that I belonged to ran a regional meet in which we
flew a number of E and F competition events, which was very rare for sections even
today. We advertised it as a meet for "you Large and Dangerous Rocket Ship fans." Also
flown during that event were actual high power rockets powered by non-certified motors.
It was only a few months later that I let my NAR membership lapse after being a member
for 14 years. When other NAR members asked me the reason, I explained that it was
because I wanted to fly rockets that would exceed the NAR's limits, and I didn't want to
cause problems by doing so. I was later told by a NAR official that this was probably the
best way to have done it, rather than openly flying high power and daring the NAR to do
something about is, as some people did.
Shortly after that I began planning what would later become the first national high power
rocket launch, LDRS. The name LDRS was an acronym for “Large and Dangerous
Rocket Ships”, just as I had heard Roger Johnson say it at Smoke Creek the year before.
LDRS was the first MRT or high-power rocketry event that was promoted as such. I
found out what I needed to do to get a FAA waiver to legally fly “amateur” rockets.
When I contacted the Oberlin Air Traffic Control Center about the waiver, they were
baffled! They had never issued a waiver before! So it was a learning experience for both
Feeling rather the rogue at the time, I even managed to get the event listed in the contest
events schedule in the Model Rocketeer, the NAR’s magazine for one issue before they
discovered its true nature. The following is how it appeared.
CONTINUED BELOW . . .
CONTINUED . . .
Then, late one night a couple of months before the launch, I received a rather nasty phone
call from a very PO’ed then-editor of the magazine, Chris Tavares, questioning me about
the true nature of the launch. So I told him. Needless to say, he was not pleased. After
that, they ran a disclaimer in the next few issues warning about "intentional amateur
activities" and urging NAR members not to attend.
LDRS-1 Sport Launch, 24-25 July, 1982, Medina, OH
(SNOAR). Three unofficial “events,” prizes to be awarded
(no national contest points). Contact: Chris Johnston,
26481 Shirley, Euclid, OH 44132; (216) 731-3839.
-From Model Rocketeer, May, 1982 Con Calendar
LDRS-1, previously appearing in this space has been
determined to include intentional amateur activity not
announced in the original notice sent to the Model
Rocketeer. NAR members are urged not to participate
-From Model Rocketeer, June, 1982, Con Calendar
We were under a great amount of pressure from the NAR officials, after all, in their
arrogance they thought that they were in control of all model rocketry (at the time even
Estes bowed down to them) and here was someone who was organizing a launch to
publicly do what they specifically forbade. This was something that they never had
happen before. Frantically, Pat Miller, the president of the NAR at the time offered to
send me a list of all active NAR members so I could check to see if the attendees were
members and forbid them to fly. Yeah … right! NAR officials attempted to coerce
certain members that they knew would be attending, asking them to write down names,
take photographs, and generally "rat" on everyone that was there. To the best of my
knowledge, no one volunteered to fink either before or after the launch.
LDRS-1 as well as LDRS-2 through 5 were all held on a farm field near Medina, Ohio.
And not a real great flying field, either. There were houses nearby and lots of trees a
short distance from the launch site. “So why did we launch there?” one might ask.
Simple! The field was owned by Mike Wagner, who was a member in the local NAR
section (SNOAR, or the Suburban Northern Ohio Association of Rocketry). It was
actually listed as a private airstrip, so it was uncultivated, smooth, and big enough for
most model rocketry activity.
LDRS-1 went off without a hitch. People came from all the surrounding states and one
as far away as California to attend. There were a grand total of 47 people at the launch.
Not 47 flyers, 47 people! For launching hardware we had the SNOAR model rocket
racks and one launcher with interchangeable rods up to ½”! A far cry from the launch
range at LDRS today! A lot of FSI E and F motor clusters were flown, along with
clusters of D12’s. Left-over Composite Dynamics motors were flown, along with
Plasmajets and SSRS motors. The highlight of the launch was rockets flown with single
composite Rocket Development Corp. H and I motors! Wow!
After the launch, the club newsletter, SNOAR News ran an article on LDRS-1 complete
with pictures. As a result, every NAR members pictured was contacted by NAR officials
about alleged "safety code violations," and several were expelled after so-called
With the success of LDRS-1, plans were quickly made to continue the launch. More
launchers were added and better crowd control was implemented. The following year,
more people came from the west coast, notably Gary Rosenfield and Korey Kline.
LDRS-2 featured the first composite J motor flown at a LDRS, courtesy of Scott Dixon
of Vulcan Systems, who attended, which was flown by the author. It also featured the
first power shred at an LDRS, also by yours truly. Korey Kline flew a bunch of his high power
Ace Rocket kits. Aerotech flew a number of prototype high-rate motors.
In the next two years, the NAR zealots tried every which way to prevent LDRS from
happening. They threatened to contact the FAA to check the waiver (I told them to go
ahead), got in touch with the Medina city prosecutor, fire and police departments, even
the Bureau of Alcohol, Tobacco, and Firearms (otherwise known as the ATF), in attempts
to shut it down. They failed.
Each year LDRS got bigger, the motors and rockets got bigger, and the NAR saw its
senior membership shrinking as more and more of them left model rocketry, ceased
model rocket competition and entered the high power rocketry sport.
By the time LDRS-3 rolled around, the NAR was forced to admit that we might be right
and started the first "Blue Ribbon Commission" for the study of high power rocketry. Pat
Miller attended LDRS-3 to observe and walked away very impressed with what he saw.
At one point during the fist day’s activities, I offered to let him launch my rocket with
clustered F100 motors, but he politely refused. It was only 150n-sec ! Later, he told me
privately that the degree of craftsmanship that he saw at LDRS, along with the way
the range was operated was better than any NARAM he had been to.
Negotiations began after that with the HPR/LDRS committee, which had such notable
high power people like Chuck Mund, Jim Dunlap, and SNOAR members Chris Johnston
and Bob Geier. Guidelines were drawn up by the committee, along with a proposed
safety code, and submitted to the Commission. Experiments were conducted by Trip
Barber to ascertain the power limits of the new composite motors. Some high power
manufacturers, including North Coast Rocketry, were contacted to give their input in
certain subjects, such as motor design and airframe construction. Others donated
materials for the testing. The Blue Ribbon Commission gave its findings, and out of this
came the new revised NAR/HIAA Safety Code, which was undoubtedly the most
profound change in the hobby since its inception.
At LDRS-4 the crowd on the field was exceeding 100 people. It featured the first
Aerotech K motor flight and the first L motor flight, another Vulcan Systems motor in a
minimum diameter airframe, which we never saw again.
Soon after this, the so-called "Son of Blue Ribbon Commission" was formed to study the
true LDRS type of rockets, over and above the 3.3 pounds which were now called Model
Rockets. Members of the Commission visited LDRS-5 and were impressed by the
quality of workmanship of the rockets, the reliability of the motors, the vehicles in flight,
and especially the strict safety rules which were enforced at the meet. The result of this
was the new NAR code for high power rocketry which allowed NAR members to fly
high-power rockets beyond the 3.3 pound weight limit.
After LDRS-4 we realized that because of motor and vehicle development, we had far
exceeded the limitations of the flying field, and for the next year there was an attempt to
hold LDRS-5 at El Dorado Dry Lake near Las Vegas Unfortunately, the FAA waiver
was refused and hastily plans went ahead to hold it once again in Medina.
Unfortunately, LDRS-5 was the last national high power launch to be held in Medina, as
the field we flew on was leased to a local farmer soon after that and plans were made to
plow it for crops. As a club, we had just one more high-power sport launch there, just a
couple of months after LDRS-5. I’m sure that we probably put a few rockets into the
Medina town square, and I think that we were really beginning to scare the locals!
Also, after the problems that happened that year, both on and off the launch range, I was
reluctant to organize any more events. Several people had attempted to use the launch to
further their personal and political agendas and I became very discouraged, not to
mention, totally burned out. Furthermore, North Coast Rocketry, the company that I
founded and was operating out of my house was consuming increasing amounts of my
spare time. With the request of Tripoli officials, I allowed the copyrighted term "LDRS"
to be used by the Tripoli Rocketry Association for the name of their national launch.
Others have followed the example that was started by LDRS and have organized other
regional type events, some with more success than others. LDRS-6, held in Hartsel,
Colorado, was the first national event sponsored by Tripoli in conjunction with Vulcan
I would like to believe that LDRS was a deciding factor in the Model Rocket Safety Code
change, and that it was also a factor for the emerging interest in high power rocketry, as
with LDRS came the development of many of the leading high power rocketry
companies that changed the face of rocketry as we know it. Never again would we think
of Estes-type model rockets when discussing rockery, Motors evolved from 13, 18 and
24mm “toy” black powder motors to 2,3, 4 inch diameter and larger professional
expendable and reload-able composite motors. From clusters of D12’s to clusters of M
motors. We now have a variety of “alternative fuel” hybrid motors. Rockets leaped from
ounces, to pounds, to tens and then hundreds of pounds. From paper and balsa wood to
fiberglass, carbon fiber and Kevlar. And there is no end in sight.
LDRS was the first, and set the example for others to follow. I can only hope that the
number of high power launches continues to increase all over the country, as the sport of
high power rocketry continues to grow
I urge the sponsors of future LDRS's to continue the tradition of well run meets stressing
safety, as LDRS is the standard all others are judged by.
Thanks for sharing, Dave. I am glad that the NAR and TRA have ironed out their differences and now allow cross-participation at national launches. also glad the NAR and TRA were able to work together to get APCP motors deregulated. We are stronger together!
The bigger question is : When are they gonna archive these threads and get up to speed. Aren't we coming up on LDRS 38??? And these threads are for LDRS 34 and 35???
LDRS Addition. The photo to the left was my 169 motor cluster record attempt. 168 A10-0t, 1 C6-7. I power. at LDRS-1. The Slobovian Avenger below, was Two records in one at LDRS-2. Full J power with black powder and it had three Cinerocs on the little bt60 pods. Motors: 12 D11-9, 20 D20 (FSI), 20 E5 (FSI) delay was too short but the rocket and all the Cinerocs recovered safely. It took some persuasion to get the range safety officer to launch this rocket due to the inherent dangers, cinerocs cannot be turned on remotely, Herb Desind an I had to stand next to the rocket and turn them all on a t minus 3 sec, with a half pound of black powder under the rocket in the flash pan... Not mentioned above, was my Short lived company, High Altitude Research and Design. HARD... coined from Moose Lavigne's signature saying for an awesome flight, "it was a real HAAAAAARD on"....I made a small number of G and H motors, including the first black smoke motor since the FSI thunderbolts. ThunderJet Macrothrusters. My unique grain geometry, part core, part quad slot gave a relatively neutral thrust curve. This grain geometry was utilized in an Industrial Solid Propulsion commercial motor for Orbital Sciences Space Data Division that went into space. The Viper V Motor (data not publicly available) The motor is about 7" diameter and has approximately 30,000 lb-sec vacuum total impulse.
Too many ways to finish that statement.
Separate names with a comma.