My Project Calliope satellite will be launched on an Interorbital Systems (IOS) rocket-- but IOS hasn't yet launched into orbit. Where are they, how close are we to launch, and what's the risk?
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The people who know are Randa and Rod Milliron, of Interorbital Systems (IOS). The person who asked is David Livingston of The Space Show. And I, your humble writer, will present this summary of the April 24th hour-long podcast.

Note to the world: if you produce a podcast, include a text transcript, please. I do with 365 Days of Astronomy and it hasn't killed me yet.

I've talked about IOS before-- their Tubesat concept is the very basis for Project Calliope. I've shown early launch rail and rocket photos, and even discussed what I can do if IOS fails. Today, I'm happy to relate the positive.

IOS's modular rocket system (the Neptune) is about to test a 1-module Common Propulsion Module (CPM) as a sounding rocket/flight test. They have a completed rocket, mobile launch rail, and FAA permit. Case closed.
IOS rocket for test flight
Suborbital for tests (only)

Oh, wait, maybe some more details will help. All their rocket plans use 1 or more CPMs, bundled for the mission needs. 1 CPM is a sub-orbital (ballistic) launch, but IOS is not interested in sub-orbital. Both host and the Millirons agreed: sub-orbital is not a natural progression to orbit, it can be a dead-end. Orbital is where it's at.

Noted Randa, "I can't stand to see things stop at suborbital, like it's the be-all end-all definition of spaceflight. It's fine as a start, if you consider moving up from that."

The 1-CPM "SR145" will list 145 kilos to 310km ballistic. Bundle together seven CPMs, you get the Neptune, doing Low Earth Orbit (LEO) missions. More, you get the Moon. But we're getting ahead of things.

Right now, they use a mobile launch system. Tests are currently at north of Mohave, in the Mohave Test Site. Tests use a FAA Class 3 waiver, so it's not a fully fueled launch. Their tests will include payloads from orbital clients who want to test communications systems (and I would presume, flight resiliancy).

Orbital launch licenses for over-ocean launches in progress. IOS, the FAA, everyone likes over-ocean launches-- fewer liability issues. For ocean type launches, condensation and icing and valves freezing is also minimized. IOS is using multiple facilities, and looking at using Wallops or Kodiak island for launches, too.


Their rockets use white fuming nitric acid, turpentine, and furfuryl alcohol. Sounds nasty, but ends up being both cheap and ecological. They note it's pretty eco-friendly: it can thrive on pine trees.

The white fuming nitric acid, specifically, is pure and concentrated, 99% pure, bought in trucks along highway, a standard industrial product-- not exotic, fairly cheap (as well as safer). It's similar in price to liquid oxygen. It has moderate performance, high density, easy storability, easy availability. In short, it's a great oxidizer.

As a bonus, they can pump it out of rocket back into storage if a mission scrubs (unlike LOX).

The turpentine is basically the regular paint-store product. Turpentine is also a renewable fuel. Its isp is 240 sec or so at sea level (using nitric acid), and it's slightly denser than kerosine. They use furfuryl alcohol for ignition-- made by Quaker Oats.

For cost, fuming nitric is about the same cost as LOX, forty cents a pound. Turpentine is less than gasoline. Furfuryl, they use only use a few pounds, at around $3/pd. So all three are very economical.

In contrast, nitro tetrox is around $25/lb, other hybrids can be higher (mostly because only 1 company makes hte hydrozine-based propellents), they're also environmentally difficult. They don't use kerosine because they want to stick with easily stored fuels and avoid cryogenics, plus kerosine doesn't burn smoothy with nitric acid.

For fuel handling, they use a closed pressurized system to transfer fuel to avoid contact with the air. Nitric acid is an irritant, not poison like red fuming nitric acid (which includes nitrogen tetraoxide). They use protective clothing and breathing apparatus in case of leak/vapors, but those are more benign than, say, hydrozine or nitrogen tetraoxide.  Full fuel specs&stats are at IOS's rocket test page.

Rockets and Payloads

The rocket is complete, the one in the photo is real! This summer: the first 2 flights. For their test/orbital flight timeline, Randa notes "everybody thinks they'll have their flight 6 months earlier", with Rod adding "our pace of development is based on our funding stream". Their current milestones are based on events and achieveables, not dates-- dates only get people in trouble.

The two emphasize being a small company. Randa: "I'm the CEO and I help make the ablative liners, I apply composites. Everyone is involved here", "it's as lean as you can get, everyone here is hands on and enthusiastic and tha's the way it should be". She addes, "those haters out there... they know what they can do.".

IOS's Rod invented the Tubesat kit, the famous $8K satellite platform + launch that Project Calliope favors, the kit that uses off the shelf parts. Rod's Tubesat is a kit he designed to work with COTS parts. IOS has also added Cubesat kits, at $15K including launch.

And as a super-secret breaking news, IOS will fly Olav Zipster up to 40,000km using a single CPM to break the high altitude fall record. It's called the free-fly astronaut mission, and I'm not making this up. This is seriously good crazy.

Upcoming milestones

  • main engine firing (completely throttleable engine design)
  • control thruster firings
  • testing guidance systems
  • launches (CPM unguided, then guided)
  • orbital 'sometime before the end of this year', date and location tbd, carrying 25-30 small satellites
Randa's closing words apply to us all: "don't ever let anybody stop you."

Until next week,

projectCalliope, converting the ionosphere to music