Just put chicken wire in it!

Akin’s Laws of Spacecraft Design #19:  The odds are greatly against you being immensely smarter than everyone else in the field.  If your analysis says your terminal velocity is twice the speed of light, you may have invented warp drive, but the chances are a lot better that you’ve screwed up.  

Dr. David Akin is the Director of the Space Systems Lab at the University of Maryland.  I have not met him, but I admire his writing.   I haven’t taken a class from him but the school of spaceflight hard knocks apparently uses his textbook.

A comment to one of my earlier blogs came in last evening.  The writer states that he had personally developed a method of making an immense amount of electricity essentially out of nothing.  We should get together, he continued, so he could share his plans with us, but he had to be careful to protect the patent by not giving out too many details.

Sigh.  Talk about unfamiliar with the basic concept. 

I did not post the comment.  Can you guess why?

When we were in the return to flight phase for the shuttle following the Columbia accident, we actively solicited public input.  We hoped that there were some good ideas out there in the public which might allow us to improve the shuttle and make it safer.  We set up a web page and an e-mail account for anybody and everybody to send their suggestions in.  We got hundreds, thousands of suggestions.  We studied them all, read them thoroughly, and responded to them individually.  It was a lot of work.  A couple of small businesses in the insulating foam world suggested that they had a product that might help.  On review, their formulations were not suited to space flight applications.  Nice thought though.  We got plenty of  . . . how can I say this delicately . . . nut case inputs.  Seriously there are people out there that need medication.  Maybe they are on it and the institution just lets them write letters.  There is the “numbers guy” for example . . . but the really nut case inputs are easily screened out.  What was the number one suggestion we got to improve the shuttle?  It had to do with the foam on the external tank.  The most popular idea – you got it from the title of today’s blog — just put chicken wire in it.

My grandparents lived in a house that was stucco sided.  That is how you put on stucco — cover your wall with chicken wire (or something a lot like it) and then apply the gooey substance that hardens and is held on to the house by the chicken wire.

We finally had to write up a form letter explaining why this was not a good idea.  I am not going to repeat it here.  Just suffice to say that some very elementary tests and analysis showed that having wire in the foam would lead to worse problems. 

I recently talked to the engineer who handled the web page and all our public input.  Out of the hundreds of submissions, did we actually get any ideas that turned out to be helpful.  Long silence on the other end of the phone.  Not really came the reluctant response.

During STS-51 when we tried to retrieve the errant Intelsat V communications spacecraft and had some difficulties capturing it, lots of folks called in to NASA asking why we didn’t just use suction cups on the spacecraft?  Hmm.  Vacuum.  Hmm.  Similarly, the suggestions to use magnets to capture the bird fell short when you realize that neither the structure (aluminum) nor the covering (glass solar cells) were magnetic.

I was disappointed.  But not, I guess, surprised.  Most of the technical subjects related to rocketry, space flight, and orbital mechanics is foreign to the everyday world that we all inhabit.  Not too many folks encounter cryogenic fluids in their day to day job, for example.

So were we wrong to ask?  Were we wrong to spend the time and effort to review all those inputs?  I don’t think so.  There is always the possibility that there is a genius out there that has THE suggestion, or at least the rudimentary idea of a suggestion that could lead to a breakthrough.  But those type of inputs are rare.  Generally, it turns out, folks who have studied and worked for many years on a complex and arcane technical subject really do know what they are doing.  The experts generally do have the right answer, or at least a number of options which may work with associated pro’s and con’s.  Just because the experts tell you that your idea won’t work doesn’t make you the next Edison . . .

I have to admit that this doesn’t sit well with me.  I’d like to believe that there are folks out there that can help us solve our problems if we would just ask for their inputs.  I hope you folks reading this will prove me right and that I am not just a cockeyed wishful thinker.

But you have got to do your homework.  The plan you propose should not violate the fundamental laws of physics and thermodynamics.  If you do propose such a plan — well, as I have heard it said, an extraordinary claim requires extraordinary support.  Handwaving does not cut it.  Oh, Dr. Akin has it again:

Akin’s Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

And there is no shortage of unsubstantiated opinions. 

In fact, another of my disappointments is in the blog-o-sphere.  NPR recently had a book interview with an author who had written an treatise discussing why the internet is so full of vituperation, mis-information, and down right personal attacks.  Being on the internet is not for the faint hearted.  I don’t mind — and in fact welcome — a civil disagreement and constructive discussion.  But some days it seems like the internet is full of people pushing their own opinions with no facts to back them up and then engaging in the most offensive personal attacks possible when people disagree with them.  Whew.  Is there some place that you get points for being clever and vindictive in your responses?

So; I am still looking for good help, good constructive, grounded suggestions or discussions on how to improve things in the nation’s space program:  both technical and managerial.  If you just want to play some nastygram game, we’re not interested.

And if you want to make a technical suggestion, I am all ears — but I’ll really be impressed if your suggestion comes with analysis which doesn’t violate the laws of physics.  And I’ll really appreciate it if the discussion remains civil.

Riding the Phugoid

Phugoid, for the non-aviators, refers to a long term longitudinal oscillation in the flight path of a flying machine. More precisely it is the exchange of altitude for airspeed with constant angle of attack.  Whew, I had to look it up in my old textbooks to get it right.  One of the on-line helps says that the engineer that invented the term “phugoid” took it from the Latin but got the translation wrong.  That figures.  Most engineers don’t know that the ancient Romans studied aircraft control.

We studied phugoidal motion a lot when analyzing shuttle re-entry.  It is most pronounced on an abort entry where the shuttle’s forward motion doesn’t create enough lift until the vehicle falls into the denser part of the atmosphere and then there is too much lift so it bounces upward to where there is not enough lift and then it falls down to where the dense air creates too much lift and causes it to climb up to where there isn’t as much air where . . . .   Well, you get the picture.  Not exactly a roller coaster, but somewhat disconcerting. 

If you are designing a re-entry vehicle with any lift at all, studying the aerodynamics so that lift and drag can be applied in the proper way at the proper time is crucial.  During the early portions of the shuttle entry, phugoids are to be avoided since they can lead to high heating which is . . . not a good thing.  Actually, the shuttle flies something called equilibrium glide for most of the entry phase.  This term refers to a state where the lift generated is exactly equal to the orbital mechanics forces and gravity.  In that state, the shuttle flies at a relatively constant altitude for a fairly long period of time, all the while bleeding off the incredible kinetic energy required to orbit the earth.

This is a good time of year to talk about how to fly through life:  are you riding the phugoid or are you in equilibrium glide?  I know where I am.  Yesterday was a real emotional high when the snow dusted my home and the shuttle flew over on its way back to Florida; then there were the stressful lows — like when I tried to untangle the Christmas tree lights . . . .

My job has continued to move away from the purely technical to a place where people skills are increasingly important.  One of my “other duties as assigned” is to represent the agency from time to time with the folks in the media.   The prospect of having this kind of interaction causes a lot of people in NASA to refuse promotions . . . engineering being generally considered to be more important than talking to the public or dealing with the media.

One of the new phenomenon in media is the blossoming of the blogosphere — exactly where we are today.  The neat thing about the internet and blogs is that anyone can spread a lot of knowledge and insight to many folks in a very rapid and inexpensive way.  The sad thing about the internet and blogs is that there is so much misinformation and personal opinion passing for fact out there.  In the last few months I have become much more involved in the new media. 

Some of it makes me miss the old media.  It is sad to see reputable old style news organizations in financial trouble laying off experienced and professional journalists, for example.  And being over the age of . . .. (ahem) 30 . . . I still prefer the feel of a real newspaper in my hands toreading streaming news off a computer screen.  But, OK, things change and we all have to learn to use the new tools.

My biggest problem with blogs and the internet — and I’m far from being the first to observe this — is the continual flame wars that go on.  Seems like everything posted attracts someone with a contrary view — that’s OK, in fact, that’s a good thing — but too frequently a contrary view stated in the most vituperative and inflammatory way.   A good exchange of views can be enlightening.  A rude exchange of person insults is just depressing.  Sigh.  Makes me want to repeat the old SNL line:  “can’t we just all get along?”  

To participate in this new world of internet interaction, you have to develop a thick skin.  Recognize the valuable components of a enthusiastic exchange of ideas and ignore the ad hominem and personal attacks and general lack of civility that seems to be rampant on the web these days. 

Its hard to avoid riding the phugoid between the highs that happen because of a great and productive exchange of ideas and information, and the lows that come with depressing and inappropriate personal attacks.

So my aerospace analogy, at least for the holiday season, is to avoid the phugoid and try to stay on the equilibrium glide as long as you have the energy. 

Hey, that probably applies to family get togethers for the holidays, too!  Don’t sweat the small stuff.