Hello All,

I’ve been reading up on the now-defunct American Rocket Company’s (Amroc’s) Industrial Launch Vehicle (ILV) satellite launch vehicles (later named Aquila), which would have used “bundled” (clustered and staged) common hybrid motors (with some versions using available solid propellant final-stage motors). The ILV-1 even had an innovative plug-nozzle first stage, made up of 12 of the common hybrid motor case/fuel grain/nozzle units arranged around a short, squat LOX (liquid oxygen) oxidizer tank, from which they all fed. (I have included links to information on—and illustrations of—the ILV/Aquila rockets below.) Also:

Before Amroc co-founder George Koopman died from injuries sustained in a car crash in 1989, the company had developed flight-ready hybrid motors of the type intended for use in their ILV/Aquila launch vehicles. Ironically, the 1989 launch failure of their SET-1 (Single Engine Test) sounding rocket/ILV motor proof testing vehicle at Vandenberg AFB (which occurred due to a frost-stuck LOX valve) demonstrated the great inherent safety of hybrid rockets:

After failing to develop enough thrust to lift off, the vehicle burned through its hold-downs, fell over, and then merely smoldered, slowly burning over the next several hours (the old ballistic missile launch pad's water deluge system wasn't operational). The base commander expressed amazement, commenting that it was the most benign launch failure he had ever seen! Sadly, the company never recovered from Mr. Koopman's death or the test launch failure, but SpaceDev acquired Amroc's intellectual property and hardware, so its achievements were not in vain. In addition:

With today’s electronic staging and recovery system deployment timers (as well as actual hobbyist hybrid propellant rocket motors), realistic Concept Scale (previously called Future/Fiction Scale) models—and even kits—of these vehicles could be created. Below are the ILV/Aquila links:

http://space.skyrocket.de/doc_lau/amroc.htm
(Amroc vehicles summary)

http://www.secretprojects.co.uk/for...mupm51d8mhkmde1
(Secret Projects UK Amroc discussion thread)

https://www.flightglobal.com/pdfarc...20-%200756.html
(Original ILV-1 design)

https://www.flightglobal.com/pdfarc...20-%200017.html
(Revised ILV-1 design)

file:///C:/Users/Owner/Downloads/Getting_Into_The_Launching_Business.pdf
(Amroc history presentation given by the late George Koopman, Amroc co-founder)

https://www.google.com/webhp?source...+launch+vehicle
(Google Amroc Aquila ILV citations)

I hope this material will be helpful.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
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All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

Having made hybrids 18" diameter with a SL ISP of 240 and higher density impulse than the Amroc designs, I can say the design is inherently practical. As with all large rocket projects funding is the biggest hurtle followed closely by ridiculous and prescriptive regulations.

If anyone wants to throw $100k at a much larger hybrid I would cheerfully build it, do all the logistics and static test it at our site with them.

Jerry

http://www.bloodhoundssc.com/sites/...g?itok=9-R5xzD8

Thank you for posting this (and for confirming what I thought was the case)! Amroc's "bundled" common hybrid motor concept (including using your 18" hybrid motor) certainly looks like it would achieve great economies of scale, through large-quantity production of the common motors. Plus:

Even "just" the safer, much simpler handling requirements for hybrids (we have expensive safety warning "motorcades" to Poker Flat every time the sounding rocket motors for each campaign season arrive) would make such vehicles much cheaper to handle, prepare, and launch. (Not having motor or igniter storage magazines out there [just a metal storage/prep building--that's all hybrid sounding rockets would need!], the Fire Chief always gets antsy about the built-up rockets staying in the building for any extended lengths of time--it's like a big game of "hot potato" every sounding rocket campaign season.) ALSO:

You're also just the one I wanted to ask the following (regarding hybrid reusability for space applications):

I posted a longer query (with ruminations) *here* (see: http://www.oldrocketforum.com/showt...4908#post204908 ), but my question is as follows:

Hybrid rockets, like liquid rockets, are throttle-able. Could a large hybrid rocket--like Blue Origin’s www.blueorigin.com LOX/LH2 New Shepard booster and SpaceX’s www.spacex.com LOX/RP-1 Falcon 9 first stage—be throttled deeply enough and quickly & smoothly enough to achieve the same vertical landing performance? (The Falcon 9 first stage apparently can’t perform a helicopter-like hover as New Shepard’s propulsion module can, but instead manages its propellant consumption [and thus its mass reduction] and its engine throttling range so that it lands gently nonetheless.) If hybrid rockets can also do this, then:

Such hybrid rocket stages could be used to create very safe--and partly or wholly reusable--suborbital and orbital launch vehicles for carrying human crews and passengers. (Their fuel grains could even be re-loaded [almost like liquid rockets' propellants] if they were loaded in a gel-that-cures-to-solid-form.) Aerojet developed this "at the pad" gel-to-solid propellant fueling concept for solid propellant Nova stages that they studied, which I described more fully in the other, above-linked YORF posting.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR