The Secret SR-72 Darkbird Missions Launching Rockets in

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APOGEEAPOGEEP E A K O F F l I G H T

The Secret SR-72 Darkbird Missions

{Ed -- This document has been circulating around theinternet recently. It appears to be a briefing by CIA aircraftpilot for a member of the Senate Arms Services Committee.}

Senator, I know there are many taxpayers that are won-dering about the SR-72 Darkbird, and its secretive missions.I'll leave it up to you to decide what information to release tothem, but I'll give you a little history of the plane. I'll followthis with a briefing about the type of top-secret missions weCIA pilots performed, and conclude with our recommenda-tions about the bill that has come before the Senate.

You may know about that other aircraft called the SR-71.It was a fast plane - with speeds around Mach 3.3. With theSR-72, the original objective was to fly even faster, and to bein the air longer without having to perform mid-air refueling.

The SR-72 was designed the a CIA front company calledApogee Components. The development of the black programwas hidden quite easily in the CIA's budget. Until recently,you might not even have known it existed. The first flights ofthe aircraft took place in the early 70's over sparsely popu-lated island chains in the Pacific Ocean. To this day theairplane's top speed is considered a national secret. But let'ssay it is well over Mach 4.4.

Suffice it to say, it is very difficult to reach these speedswithout the assistance of rocket power. That is why the core

module of the SR-72 houses the powerful and ultra-efficientJ7 rocket engine. It is a remarkable engine, as it is able to useatmospheric oxygen that is ducted in from the two outboardengine cowlings. This saves a lot of weight, since separateoxidizer is not needed for the rocket power portion of the flight.This allows the plane to carry much more fuel, giving it theloiter time over the target that is required for many of its mis-sions.

As you know Senator, the old SR-71 did not carry arma-ments, whereas, the SR-72 is a CIA airplane, it does. The pri-mary weapon is a large Bolaero/Z Air-to-Space missile. Be-cause of the high launch speeds of the SR-72, the missile canreach targets that may be in geosynchronous orbit.

Initially, early missions of the plane where to take out"ORANGE Country's" space launchers. You probably remem-ber that the success rate of those launches appeared to be dis-mal. Most people thought that the "ORANGE Country's" spaceprogram was run by a lot of incompetent engineers. But inactuality, we took out the launchers with air-to-space missilesfired from the SR-72 Darkbird.

That's why the need for extra speed was critical. We'dloiter over the mountains waiting for a rocket launch. If ev-erything went right, we pilots would get a message from CIAheadquarters about the countdown. As you know, it was partof the CIA's job to have intelligence agents on the groundmonitoring all their launches.

If the launch looked imminent, we'd ignite the J7 rocketengine to full thrust. It was a real kick in the butt as I'd burnthrough the upper layers of the atmosphere and try to be in aposition to launch my own air-to-space missile. Our objectivewas to get a good run on the rocket just as it cleared 30,000feet. The faster we went, the greater the possibility of a suc-cessful termination, since the window of opportunity was sovery short.

We SR-72 pilots weren't successful every time, but wehit enough of the rockets in the first few months of operationto make their space program very expensive. Because of this,they had to divert money from other military programs. It wasa double bonus for our side.

Did "Orange Country" know what we were up to? You

cont. on pg.3


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cont. from pg .2

PAGE 3



other F4 flying in forma-tion witnessed whathappened. A Unidenti-fied Flying Objectswooped down on thefirst F4, and launchedsome type of hi-speedprojectile. After thatplane was destroyed, itcame after the secondF4. It was also hit by aprojectile, but the pilotwas able to eject suc-cessfully.

To this day, wedon't know where theUFO came from. Butthis was a far bigger na-tional security threat tous than "Orange Country." We are dealing with an advisorythat is much more technologically advanced than we are. Sowe ceased SR-72 missions to destroy "Orange Country's" spacelaunchers.

Heck, Senator, we knew that our entire planet was at risk.So we devised a plan to get the assistance of "Orange Coun-try" to aid us in defending humanity.

Do you recall that link-up of astronauts in space in 1975?It was the only way we could think of to share informationwith "Orange Country" about the threat from the aliens. Toour knowledge, they hadn't yet encountered the aliens; so weneeded proof that they existed.

Some crazy scientist at Apogee Components figured outthat the aliens would be monitoring that space link-up mis-sion. And sure enough, they did show up. It was profoundevidence, and we were able to convince "Orange Country"that the threat from the aliens was real. That day was the be-ginning of the end of Cold War.

Senator, it was pure luck that we did have the SR-72Darkbird in our arsenal at the time. It gave us some limiteddefense against the aliens when they flew down into our at-mosphere. It was fast and maneuverable enough to chase away

bet. Once we ignited the J7 engine, we were very easy to track.But by that time we were already chasing their rocket. Andyes; they did all types of things to try to circumvent our plans.Launching decoy rockets worked for a while, so did having afake countdown. But a lot of times, we knew they had limitedlaunch windows for their rockets, so those missions were a bitmore successful.

We never went after manned vehicles; and they knew it.It would have drawn too much attention to their space pro-gram. People would have demanded answers, and we mighthave ended up exposing our own SR-72 aircraft.

They couldn't protest against our flights publicly; prob-ably because they couldn't face their population with the newsthat we had a plane capable of such performance. They tookgreat pride in their aviation industry, and they just couldn'tadmit they weren't able to create a plane with similar capabili-ties.

Also, until 1994, it was a federal crime to take any photo-graphs of the SR-72, so the "Orange Country" had no ideawhat the plane looked like, nor how big it actually was. Whilethe SR-72 has a similar shape to the SR-71, it is a much biggeraircraft. It is almost twice the size!

It was a very stealthy aircraft while operating under nor-mal scram-jet power; although it is a bit noisy. But flying upabove most of the atmosphere muffled the ground noise to asignificant extent. But once we ignited the J7, we were veryeasy to spot on radar, and with infrared tracking systems.

By around late 1974, the "Orange Country" had devel-oped significant countermeasures that made our missionsnearly impractical. They figured out how to stage their rocketsat critical times in the flight, which would present multipletargets to the missile we fired at them. This would confuse themissile's guidance system, and it usually went after the largeportion of the rocket. Obviously, that was the wrong part asfar as we were concerned.

Senator, now I'll get to the part about the aliens.

On April 1, 1975 an Air Force F4 Phantom jet mysteri-ously exploded while operating a routine training flight overColorado. That is what the news reports said anyway. But an-

The Secret SR-72 Darkbird Missions

cont. on pg.4


I S S U E 8 1 - M A Y , 1 7, 2 0 0 2

PAGE 4



the alien UFOs. We haven't been able to shoot any of themdown, but we are getting close to that point.

The scientists at Apogee Components are working on somenew weapons that they think will be able to terminate the UFOthreat. That is why you need to spend money on their non-military rocket vehicles; so they can funnel the profits into theblack programs the CIA has them working on. Senator, they'redoing great things for our planet, and they need to be rewardedfor it.

Senator, this gets us to the legislative billcoming before congress this week. As youknow, this bill would authorize; or rather"force" NASA to send astronauts back to themoon. In the CIA's opinion, this would be aterrible mistake. We know the aliens are outthere in space. We can defend ourselves whenthey enter our atmosphere; but we cannot de-fend astronauts when they leave low earthorbit. They would be sitting ducks for thealiens.

So Senator, it is our opinion that the USpopulation would be horrified if our astronautswere blown up on their way to the moon. Itwould be better for the time being to kill thebill in congress. You might say that money isbetter spent giving the elderly more healthcare.

As you might guess Senator, the alienthreat has been a reason why NASA has notsent men to the moon since 1972. There has been a lot of pres-sure from space geeks, but the CIA, acting with previous ad-ministrations have been able to thwart those efforts up to now.

We fully expect that we'll develop a way to protect theastronauts in the future, but for now, we can't admit the aliensexist -- not yet anyway.

We need the status quo in place a little while longer yet.We need to continue to send men into low earth orbit to con-struct the new particle weapon being placed aboard the "Inter-national Space Station." It will become our staging point forfuture operations against the aliens.

But we can't risk going to the moon right now. It might

The Secret SR-72 Darkbird Missionsexpose everything and send the planet into a terrified panic. Ifthat happens, who is going to pay their income taxes? Withoutmoney Senator, we won't be able to pay contractors like Apo-gee Components to develop the technology to defend ourplanet.

Senator, please vote "no" on the NASA appropriations billthis week.

Obviously, the above article is pure sci-ence fiction. I wrote it myself. (©2002 - TimVan Millligan)

But the Apogee Components' SR-72Darkbird model rocket kit is real! And youcan own one today.

If you are like most modelers, you likerockets that have a swoopy aerodynamiclook to them. The "SR-72 Darkbird" is onesuch model. It may look like an airplane,but trust me; it's all rocket power.

The stealthy SR-72 aircraft blasts offon rocket power,taking you along on its su-per-secret mission. It is a awesome launch,capable of defending our planet againstthose pesky alien invaders. And when itsmission is completed, it glides gracefullyback to the ground; ready to take on the nextadvisory. You'll like flying it again and again.

Order one today at:

http://www.ApogeeRockets.com/SR72_Darkbird_Kit.asp

Specifications: Skill Level: 4 - Slightly ChallengingPrice: $12.95Length: 35.6 cm (14.0")Diameter: 18 mm (0.736")Weight: 30.0 grams (1.05 oz)Recovery Type: Glide with a streamer for power pod.Recommended 13mm Rocket Motors: 1/2A3-2T (first flight),A3-4T, A10-3T,B7-6

cont. from pg. 2


http://www.apogeerockets.com/sr72_darkbird_kit.asp.

PEAK OF FLIGHT

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Websites of the WeekI've been trying to make this a regular feature of the Apo-

gee rocketry e-zine newsletter. There is so much good infor-mation on the internet, that But I keep getting other articlesthat have more urgency. Since this issue has a orbital mechan-ics theme to it, I thought it would be cool to review some realspace projects.

Recently, NASA put up a web site showing concept draw-ings of the follow-on rocket to replace the SpaceShuttle. This new vehicle is currently under a projectcalled the "Space Launch Inititive." You can find somereally neat photos of the concept vehicles put forthby various NASA contractors at: http://www.slinews.com/concepts.html

It is interesting to note that nearly all thenew concepts are winged vehicles; much likethe current Space Shuttle. If you're a builderthat likes glider rockets, you're going to lovethis web site. There are lots and lots of thingson this page that will give you inspirationalideas.

I've downloaded a couple of the movies from the site.They are sorta neat to see, even though the ones I downloadeddidn't have any sound.

Our second site on this weeks list of ones you should takea look at is an article written by Robert Truax. Mr Truax is anoted aerospace engineer, that worked on a variety of the

launch vehicles of the 50's and 60's.In his article called: "The Future of Earth-to-Orbit Pro-

pulsion," he gives his opinions on what it will take to lowerthe cost of placing rockets into orbit. It is worth reading, be-cause it is a direct contrast to the direction that NASA is tak-ing with the Space Launch Inititive.

About winged spacecraft, he writes: "The only justifica-tion is the unprovenassumption that ifthe configurationlooks and acts likean airplane, it willhave operating costslike an airliner's.This is the argumentthat NASA used forthe Space Shuttle,but there was nobackground of ex-perience to supportthat assumption. Ithas been proven tobe a very costly er-ror: The SpaceShuttle represents a

truly marvelous implementation ofan absolutely absurd concept. Its de-velopment and use have cost some$20 billion-$40 billion, and it has setback economical access to spaceabout 35 years."

It makes you wonder if theSpace Launch Inititive will be a suc-cess, or if it will be another footnote

in the history of rocket programs.The web site where you can read the entire article is at:

h t t p : / / w w w . r o c k e t r y o n l i n e . c o m / S e a r c h /db_search.cgi?setup_file=Opinion&submit_search=yes&db_id=36


http://www.slinews.com/concepts.html


http://www.rocketryonline.com/search/db_search.cgi?setup_file=opinion&submit_search=yes&db_id=36



http://www.rocketryonline.com/search/db_search.cgi?setup_file=opinion&submit_search=yes&db_id=36

I S S U E 8 1 - M A Y ,1 7, 2 0 0 2

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cont.on pg.7

Mercury TransportArticle by: Nick Esselman,Introduction by: Tim Van Milligan

Nick Essleman recently sent me a prettyunusual rocket design called the "MercuryTransport." The picture below shows whatmakes this design unique. The fin spans thelength of the rocket, the middle part of the findoesn't touch the rocket's smaller diameter tube.

Obviously, this configuration is a violationof the Barrowman Stability Equations thatwe've all used to find the Center-of-Pressure(CP) of the rocket. But, as Nick describes inhis article, he found that the RockSim softwareis able to calculate a CP location of the design.And to prove it works, he's successfully flownthe rocket. Since Apogee Components sells theRockSim software, I really like the article as itpoints out yet another good reason why youshould buy the software. If you don't alreadyhave it, you can download the free demo ver-sion from the Apogee Components web site at:http://www.ApogeeRockets.com/rocksim.asp

Unfortuantely, due to space limitations inthis newsletter, I had to trim the article. Thepart I cut out was the step-by-step instructionson building the model. Fortunately, Nick didput these on his web site at: http://www.rocketreviews.com/reviews/scratch/mercury_transport_18mm.html On his site, youcan also download the RockSim .rkt design filefor the model. Take a look, its pretty neat.

The rest of this article is by Nick Esselman.

The Mercury Transport is a new designfrom Essence Aerospace Technologies (EAT).Its main purpose is to transport 4 passengersthe 91.8 Million Kilometers to the planet Mer-cury for observation, study and experimenta-

tion in a high temperature, zero gravity, highsun-radiation environment. The Mercury Trans-port has fins that are suspended over the innerFusion Proton Rod Reactor Core. The fins arein a test configuration for future interstellartravel and to assist in cooling the core as theship passes close to stars (such as our Sun). Theship is primarily designed for long distancetravel. In fact, 95% of the entire ship is a reac-tor to allow the ship to travel the distanceneeded.

I began preparing to build a Mid-HighPower rocket with this unique (at least I've neverseen anything like it) fin and body configura-tion. So, in preparation I wanted to build asmaller 18mm prototype to test design and sta-bility. This article describes the assembly andperformance of the prototype which turned outto be a nice rocket in itself. There is also a threadon The Rocketry Forum (http://w w w . r o c k e t r y f o r u m . c o m /index.php?referrerid=35) that I initiated whenI started this process.

Before I get into the flying of the MercuryTransport, I want to discuss a new finding forme about RockSim Free Form Fin Design. WhatI found is that when you go into the Free FormEdit page the point at "0, 0" and the farthestpoint to the right at "x, 0" are set. In other wordsthe "0" on these two points is the establishedbase line and are not changeable in RockSim.If you go ahead and draw out your fin patternwith the right-most point remaining as the "x,0" then the fin will "touch" the body tube forthe entire length of the root edge. In the Mer-cury Transports case, the fin spanned across thetwo different diameters of the tubes and there-fore this made the root edge conform to the in-ner tube as well as the outer tube.

My design was for it to "bridge" the innerRockockSim

Created in


http://www.apogeerockets.com/rocksim.asp

http://www.rocketreviews.com/reviews/scratch/mercury_transport_18mm.html



http://www.rocketryforum.com/index.php?referrerid=35



I S S U E 8 1 - M A Y , 1 7, 2 0 0 2

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tube, not touch it. To make this work, I had to move the right-most point to be the second point from the left (in my case"0.5, 0"). The third point from the left had to be right abovethis point (in my case "0.5, 0.001"). By setting this to be"0.001" on the y-axis I was able to create the "bridge".After spanning the inner tube length including transitionsI had two points again. One was at "14, 0.001" and theother right below it was "14, 0" which brought the finsroot back into contact with thelower tube section.

What difference does itmake? Major! The position ofthe CP with the root touchingmade the rocket appear, by cal-culation, to be unstable or mar-ginally stable. With the fin trueto design the rocket, by calcu-lation, was over stable.RockSim calculations still hadthe CP on the rocket, whileBarrowman had the CP way offthe back of the rocket. Flightproved the stability of the de-sign!

FLIGHT/RECOVERY:

My first flight was on anEstes B6-4. It was absolutelyperfect and I can't describe itany differently. Stable andstraight. It is a little heaviermodel so the lift-off is not light-ning fast allowing you to enjoyit. At apogee the rocket seemedto hang parallel with the groundand just as it appeared to stopand start down ejection oc-curred. The 'chute opened and it descended safely to recovery.

The second flight was on an Estes C6-4. Again stable and

straight, just higher. At apogee it again was parallel to theground when ejection occurred. One panel on the plastic 'chutestuck to itself causing less than full 'chute opening. That wasokay because it was a little windy and this thing drifted down

the length of the field. Whilereloading the 'chute Isqueezed the Cooling Fins abit too hard and cracked oneat the attachment to the uppertube. Not broken through.

The third flight was backon the Estes B6-4 for anotherrepeat of the first flight. Thistime my 'chute got tangled inmy heat shield and did notopen. Recovered with nodamage.

SUMMARY:

The Mercury Transporthas inspired me to press onwith my 4" / 2.6" / 4" version.Can you scale up a rocketwithout impacting CP/CG re-

lationship? Read Apogee's Newsletter Issue 80.(http://www.night.net/apogee/Newsletter80.pdf)

I would suggest that you strengthen the fins byCA'ing or a light paper cover. Whatever your favor-ite method is. Other than that, I think it is a nicerocket and would love to hear and see any experi-ences that you have building and flying this design!

About the Authoer: Nick Esselman is thewebmaster of Essence's Model Rocketry Reviews(http://www.rocketreviews.com) and has been usingRockSim for 4 years. Nick can be contacted [email protected]

cont. from pg. 6Mercury Transport

http://www.rocketreviews.com


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Launching Rockets in SpaceBy George Gassaway & Tim Van Milligan

{Ed. This article first appeared in theJanuary 1991 issue of Space Coast Rocketry.This was a club newsletter edited by PatrickMcCarthy and Tim Van Milligan. Some of theacronyms may have changed since 1991, butthe laws of physics haven't -- therefore, theidea of launching a rocket in space are stillvalid.}

Launching a small satellite from theshuttle cargo bay is not a novel idea. But ifthe satellite was very small, it could belaunched with the aid of a model rocket mo-tor.

One method of deploying a satellite isusing the Payload Assist Module (PAM) con-cept.

This approach has been found by NASAto be extremely reliable. It involves pushingthe satellite directly out of the cargo bay bysprings in the direction of the desired orbit,and then firing a solid rocket motor to boostthe payload into an elliptical transfer orbit.

As simple as the shuttle PAM-type sat-ellite deployments are, a model rocket can dothe same type of thing for the initial boostphase. The aspect which is not so simple iscircularizing an orbit since that would requirea second precise firing at the proper time.While that might be possible to do with a spe-cialized small motor and an on-board elec-tronic timer, this article will concentrate onthe initial boost phase only.

We make the assumption that the modelwould be deployed from the payload bay ofthe space shuttle from low earth orbit. NASAwould have to relax the Get-Away Special(GAS) rules to actually allow such a thing, ifit were done as a GAS experiment. Other-

wise, the only other likely scenario wouldbe to develop an actual scientific missionthat would interest NASA in launching theirown model-rocket-powered micro-satellites.

As for the deployment, the model rocketwould include its own launch platform in-side the GAS can.

The launch platform would be disc-shaped, perhaps with extra mass at the rim,so that when spun up it would be spin stabi-lized.

To alleviate small thrust-line errors inthe engine, everything would be spun up fastenough so that any misalignment could beevened out. This likely would requireslightly higher rotation rates than PAM-typedeploys, due to the small rotational inertiaof the engine/payload combination.

The model rocket/micro-sat would bedeployed from the shuttle just as a PAM.Also like the PAM, aiming of the micro-satprior to deployment would be accomplishedentirely by aiming the shuttle's payload bay,since the satellite carries no attitude controlequipment.

At the proper time and pointed in theproper direction the shuttle would release themodel rocket which would slowly rise upout of the bay, and the shuttle would moveoff. The payload is pushed out of the canis-ter and off the spin-table by a group ofsprings. The tolerances on these springs mustbe very critical! If one spring should pushharder than the others, the satellite wouldbe aimed in the wrong direction at the timeof motor ignition.

An electronic timer (or timed ordinancefuse) in the launch vehicle (i.e. the satellite)would fire the model rocket at the propertime, just as PAM's typically fire 45 min-utes after deployment, so that the shuttle isfar enough away. The model rocket would


cont. on pg.9

PAGE 8

Satellite vehicle chechoutand spin-up sequenceinitiated

Satellite deployment and coast

Automatic Ingition and spin-stabilized burn of upperstage


PAGE 9


minutes after deployment, so that the shuttle is far enoughaway. The model rocket would go on its way, leaving the launchplatform behind.

If desired, the launch vehiclecould include a retrofire modelrocket motor to bring it out of or-bit, so that the payload might be re-trieved, or bring it into a lower or-bit where it could decay and re-en-ter the atmosphere in a shorter time(Space junk is becoming a very se-rious problem, so we would notwant to be considered a litter-bug).

The model rocket could benothing more than a model rocketengine, but it probably would needa special nozzle for vacuum opera-tion, and it would also have to betested in a vacuum chamber (a airbubble inside the propellant couldcause the motor to explode beforeit is ever ignited).

Except for the novelty of fir-ing a model rocket in orbit, launch-ing the engine alone would not beof much note (unless done as partof a speed record where payloadmass would hurt too much). Formore performance, it could also bestaged.

One possible scientific use ofan engine casing by itself could beto hit the moon. If the Apollo seis-mic sensors still worked and theimpact of a 2-3 ounce mass at highvelocity could provide a readable and useful result. That's areally CHAD way to try it (although this might require a veryclose hit though - maybe less than 50 feet). Given the crude-ness of how the old Juno-II took pot-shots at the moon usingspinning solid powered upper stages, it seems reasonable tobelieve a model rocket could do it. It might even have a betterchance of working since it would have the accuracy of a shuttle

PAM type deployment rather than the more error-prone guid-ance aiming of the Juno-II.

From the equations of orbital mechanics given in the Sep-tember - October issue ofSCR, it is possible to find outthe size of the motor neededto put a specific size payloadin any desired orbit. For ex-ample: to put a payload intoan orbit with an apogee at384,000 Km (the orbital ra-dius of the moon), and assum-ing the motor is of the ad-vanced composite type (Isp =2100 m/s), you would findthat you would need 1.29 Kgof propellant for each kilo-gram of payload. So if youhad a satellite of 9.75 Kg(21.5 lb), you would need atleast a size "N" motor (totalimpulse = 20,480 N•s). Thatwould be a little too much im-pulse to send it to the moonthough, because the moonwould exert a gravitationalforce that would increase thevelocity of the satellite whenit got close enough (see side-bar for an explanation of thisgravitational effect). It mightbe possible to use the extra ve-locity to sling the payload outof earth orbit and into a plan-etary rendezvous mission.

Regardless of the type of mission, you probably couldn'tconvince NASA to let you accomplish any mission if the mi-cro-sat would be in a orbit less that 10,000 miles. For orbitsunder this altitude, you could likely use the tethering tech-nique to place a small payload into that orbit. If you couldsomehow use the PAM concept launched from a tethered sat-

Launching Rockets in Space

I S S U E 8 1 - M A Y , 1 7, 2 0 0 2 APOGEEAPOGEEP E A K O F F l I G H T

get-away-special launched micro-satellitesingle rocket motor (no apogee kick motor)

Satellite

Rocket Motor

Top View of Satellite & Rocket Motor

Satellite

Model Rocket Motor

Push off Spring

Spin table

Spin table electronics

Spin Axle

cont. on pg.10

cont. from pg. 8


ellite, you could really get some exceptional velocity changes(launching from a tethered satellites is similar to slinging asmall stone from slingshot - like David and Goliath).

A model rocket could not boost much of a payload, sopayloads would have to be very miniaturized and lightened,or special type of payload and missions considered. NORADmight have trouble tracking something as small as an enginein high earth orbit, especially if it were to leave earth orbit.One possible payload would be to carry an Echo-type mylarballoon. A balloon 1-3 meters in diameter would weigh rela-tively little, most mass would probably concern the device forinflating it properly without bursting. The aluminized coatingwould help reflect radar waves very well, making it fairly easyto track (though I have no idea how well it could be trackedbeyond a few hundred thousand of miles). If sent off at be-yond Earth escape velocity, it could be sent in a general direc-tion within the solar system, early tracking before getting toofar could establish its likely course, though it could not beexpected to reach a specific target without additional naviga-tional capabilities.

Or could it? If a person is riding in a car moving at 10mph and throws a ball horizontally backwards at 10 mph, theball will essentially fall straight down, with no horizontalmotion in respect to the ground. Now imagine the earth beingthe car and the rocket being the ball. If the rocket is fired at theproper point in Earth orbit, it could be made to in effect be"thrown backwards" from the Earth's orbit around the sun, inrelation to the sun it would accomplish a major retrofire ac-tion that would result in a net orbital velocity around the sunof near zero. That done, it would pretty much fall straight to-wards the sun. I know the orbital mechanics are a bit trickierthan that such that leaving the Earth would have to take intoaccount the Earth's gravity until it gets out of its influence, butit seems not to be too difficult for someone to figure out. Thisapproach would seem to allow a large enough margin of errorfor too little or too much performance by the engine so that itwould still have a good chance of going into the sun.

Guess it could the called the "Solar Minimum Mission?"What scientific purpose? I don't know. Perhaps as little as be-ing able to say a manmade object hit the sun (or more accu-rately was enveloped, vaporized, etc.). When an early lunarshot missed the moon a big deal was made out if becoming the

There is still time left, and since only a few entries havecome in, you're odds of winning the prize is pretty good.

Shrox has been creating some awe inspiring rocketry art-work in the Apogee e-zine newsletter. You see examples of itwith the free rocketry plans. I thought that the story behindthe artwork is missing. For instance, what is the story of therocket, and how did it get to the point where it is shown in thepicture?

To find out, I'm holding an essay contest. Pick a rocketpicture from the list below, and write a fictitional story aboutit. I know you daydream about these rockets, since I do it too.So just write down your story and send it in for your chanceto win a cool prize!

SHX/TVM-01 - newsletter #73Stonebreaker/AX - newsletter #75Bolaero/Z - newsletter #76Orion Luxury Shuttle - newsletter #78There will be two age divisions: 17 and under, and 18

and older.First Prize: $50 Apogee Gift CertificateSecond Prize: $25 Apogee Gift CertificateGuidelines:Maximum word count:1000 words.Deadline for Entries: May 17, 2002Format: electronic *.txt files.Email the stories to: [email protected]

Apogee Components reserves the right to re-print the es-says in the free e-zine newsletter so that other readers canenjoy the stories too.

Rocketry Essay Contest $150 in prizes!



first manmade object tofly past the sun. But Idon't think anything has

actually gone directly towards the sun.Oh well, some pretty wild stuff. There might be some

very good uses for a model rocket in orbit but none of theright people are thinking about anything like that. Possibly abit like the laser, nobody knew what to do with it when firstcreated, but there have been many uses developed.

So, there it is. The Getaway Special that really gets away.

Launching Rockets in Space

PAGE 10




Three Body Problem

Archives of this NewsletterAll the articles that have appeared in this newsletter are archived athttp://www.apogeerockets.com/education/newsletter_archive.asp

By Tim Van Milligan

The trip to the moon is more complex than tossing a ob-ject into the vicinity of the moon. The problem is termed byastrodynamicist as athree-body problemalthough, more cor-rectly it would be themulti-body problembecause in manycases there is morethan three masses ex-erting a force on thebody in question.With the help of sometext from Principlesof Astronautics by M.Vertregt, I will at-tempt to show the dif-ferent forces acting ona space ship travelingfrom the earth to themoon.

In figure 1 theaccelerations causedby the forces of attrac-tion of the Earth, theSun, and the Moon ona space ship, areshown as fractions ofthe acceleration on the Earth’s surface (go).

We can see from this that the attractive force exerted bythe Sun on Earth’s surface is only about 1/1600 of the forceof attraction exerted by the Earth. At a distance of about260,000 Km (161,500 miles) from the Earth, the Sun’s at-traction is equal to that of the Earth, and the Moon’s attrac-

tion is still about 100 times smaller.At a distance of 346,000 Km (215000 miles) from the

Earth and 38,000 Km (23,600 miles) from the Moon, at whatis called the neutral point N, the attraction exerted by the Earthis equal to that exerted by the moon (this is not L1, one of thefive Lagrange libration points; L1 is actually located 58,000Km from the Moon’s surface). The two forces are here in equi-librium, but one must not assume that there is no attractive

force in this area, be-cause we can see thatthe Sun’s attractiveforce at this point isalmost twice as largeas that of the Earth orof the Moon, takenseparately

At a distance of30,000 Km (18,600)miles from the Moon,the attraction exertedby the Moon is equalto that of the Sun, andmuch greater thanthat of the Earth, andat a slightly greaterdistance from theMoon’s attraction be-gins to predominate.At the Moon’s sur-face the gravitationalforce is about 1/6 ofthe gravitationalforce on the Earth’ssurface. The Sun’s at-

traction remains approximately constant during the entire tra-jectory, and the graph showing the Sun’s gravitational attrac-tion remains practically horizontal. In any case, this showsthat the space ship is attracted on its way to the Moon not byone body, but by several bodies.

Moo

nEarth

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 x 10 km4

Distance from the Earth's center

Earth's surfaceMoon's surface

Distance from the Moon's center

1x 10 km

1.65 x 10

6.07 x 10

2.75 x 10

-4

-4

-4

-4

-1

-1

Sun

N

7 6 5 4 3 2 1

age

10

10

10

10

-3

-2

PAGE 11


http://www.apogeerockets.com/education/newsletter_archive.asp


I S S U E 8 1 - M A Y , 17, 2 0 0 2 APOGEEAPOGEEP E A K O F F l I G H T

SR-72 Darkbird - Edge of Space Research Plane

Conduct some high altitude

researchwith this decal

conversion for the

Apogee SR-72 Darkbird.

http://www.ApogeeRockets.com/shrox/sr72.asp

PAGE 12


Documents

The Secret SR-72 Darkbird Missions Launching Rockets in