Paper airplanes from space?

[CraigD]

New stories of a team headed by Takuo Toda of the Japan Origami Plane Association and Shinichi Suzuki of the University of Tokyo to throw about 100 paper airplanes from the ISS (see BBC NEWS | Asia-Pacific | Can Japan's paper plane fly in space?, Paper aeroplane to be dropped 240 miles from International Space Station to Earth | Mail Online) passed largely without discussion when they appeared in early 2008. I just stumbled upon an article in, of all places, the 2008/11 issue of Funny Times.

Reaction to the story in early 2008 appears mostly to note that the proposed test is, for lack of a better word, silly. I’m intrigued by questions the idea raises, such as:

• can a 0.2 m, 0.3 kg plane made of “heat resistant paper” survive reentry?
• if so, would 100 of them bearing multi-language instructions to return them to JOPA give a reasonable expectation of at least one of the planes being recovered?
• Is the proposed experiment worthwhile?
• If successful, what are the practical implications?

[Roadam]

If I think of it quickly, I would say that it is possible that a paper plane would get down to earth in one piece. As it is very light its terminal velocity is low and so it wouldn't just burn when descending.

I would have to investigate though.

As for throwing paper planes out of ISS. It may take some time before they make it down to earth, I think quite many orbits. And it may be easier to just bring a stack of A4 papers up there and let astronauts make paper planes in their free time.

[freeztar]

Originally Posted by CraigD

If successful, what are the practical implications?

This is the overarching question in my mind. I don't see how it could be useful.

Perhaps very small payloads could be sent to Earth this way, but why not just piggyback those payloads on other return missions? (like they are already)

Tracking would be a major issue as well...

[CraigD]

Originally Posted by freeztar

This is the overarching question in my mind. I don't see how it could be useful.

Perhaps very small payloads could be sent to Earth this way, but why not just piggyback those payloads on other return missions? (like they are already)

It takes some stretching of the imagination, but the following ideas come to mind:

If “paper airplane” reentry vehicles work, I suspect they’d be very reliable. Presently, reentry and recovery of small, valuable payloads is a critical point of failure. The Genesis solar wind sampler, which crashed, contaminating its returned material and significantly reducing its scientific value, comes to mind. In case like this, a “paper airplane” system, even one in which some or most of many vehicles were lost, might be a better design.

The same reasoning applies to atmospheric entry on bodies other than Earth. In particular, might a “paper airplane” system be able to deliver material to Mars, without the material cost and points of failure required by current aerobraking techniques?

Finally, speculating pretty wildly, can the approach be scaled up to larger payloads? Could a “dandelion puff” vehicle made of some large, diffuse material reenter a manned vehicle? Could an even larger, similar system land something beyond current technological means, such as a valuable metal-rich asteroid?

Originally Posted by freeztar

Tracking would be a major issue as well...

Somewhere in the articles describing Toda and Suzuki’s plans, a “next generation” vehicle including miniature tracking and guidance systems, is mentioned. Given that without such systems, a surviving vehicle can end up literally no-one-knows-where anywhere on Earth, such systems seem critical to the approach having any practical value.

[freeztar]

Originally Posted by CraigD

If “paper airplane” reentry vehicles work, I suspect they’d be very reliable. Presently, reentry and recovery of small, valuable payloads is a critical point of failure. The Genesis solar wind sampler, which crashed, contaminating its returned material and significantly reducing its scientific value, comes to mind. In case like this, a “paper airplane” system, even one in which some or most of many vehicles were lost, might be a better design.

Thanks for the reminder of Genesis and the excellent wiki link on it. Genesis had a mass of 275kg. Could a 275kg "paper airplane" survive reentry without extensive "non-paper" (which would increase mass) altercations? (Given, the airplanes are heat treated paper that withstood temps of 300C in the lab.)

The same reasoning applies to atmospheric entry on bodies other than Earth. In particular, might a “paper airplane” system be able to deliver material to Mars, without the material cost and points of failure required by current aerobraking techniques?

That's a good point, but again, I think the whole idea is very "mass dependent".

Finally, speculating pretty wildly, can the approach be scaled up to larger payloads? Could a “dandelion puff” vehicle made of some large, diffuse material reenter a manned vehicle? Could an even larger, similar system land something beyond current technological means, such as a valuable metal-rich asteroid?

You lost me here. How could this design benefit from any other in reaching an asteroid? It seems to me that the whole point of having the "airplane" design is to be capable of working with air, or some form of atmosphere.

Somewhere in the articles describing Toda and Suzuki’s plans, a “next generation” vehicle including miniature tracking and guidance systems, is mentioned. Given that without such systems, a surviving vehicle can end up literally no-one-knows-where anywhere on Earth, such systems seem critical to the approach having any practical value.

I must have missed that reference in my skimming, I'll look again (though I haven't seen the "funny times" link yet as the link you gave directs to the home page).

I agree that it seems critical for practical value. The system described in the articles, marking 100 'darts' with different languages, seems gimmicky.
It reminds me of when my 3rd grade class let loose ~30 helium-inflated balloons with messages attached urging the wayward recipient to return the message via mail to each child's home address. All of us were thrilled when one of our classmates actually got a letter back! I found out later that the kid got his mom, a teacher at the school, to forge the fake mailing. It became obvious that something was fishy when the return and mailing address were the same.

On a side note: Kids are not as stupid as people think! They figure stuff out!