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Post by Tom Goodrick on Nov 3, 2012 8:26:57 GMT -5
I am very saddened. The US has allowed a substantial amount of knowledge and expertise to fall into decay. I define "expertise" as the ability to resurrect the knowledge need very readily as when an expert does not need to work a problem from the beginning. He has solved the problem before on paper and he just has to dig through some notes and then he resumes his prior work, perhaps directed more specifically at new program parameters. In 1990, I was assigned to begin work on aerobrakes. I knew nothing about it but everyone assummed that, since I had some expertise in parachutes, I could pick up on aerobrakes. It was a hassle. Parachutes involved mainly aerodynamics and structural analyses of light-weight fabrics. Aerobrakes are fairly heavy, rigid, and involve aerothermodynamics and research in heat dissipation. But I found some local scientists in Huntsville who had worked the problem 20 years earlier for robotic landings on Mars and Venus (that worked fine). I read their papers and we called them in for briefings and conferences.
The Apollo Lunar Return problem is an example of aerobraking although it relied partly on chemical braking. Aerobraking is the process of building a spacecraft to handle entry heat and to manage trajectories so that the orbital energy is dissipated. Weight penalties raise launch costs for both chemical and aerodynamic braking. Studies have to be made as to which is best for a given mission.
I remember walking to the rental car in parking lot with two of these experts noting that I was a "young 49-year-old" while they were in their 60's. We had attended a conference in Washington at which the people at the top had said our aerobrake efforts were too extotic and would probably be cancelled. I had also recently given a paper at an international conference in Montreal on aerobraking where I presented a new empirical relation that was well-received. I remarked to the older guys that I felt I was just beginning to understand the problem they had worked years earlier and now my work as well as theirs would be shut down and would collect dust for another decade. (Try two or three more decades.) Then some other young people would take it up.
After shutting down my aerobrake work, I had time to develop a new general purpose entry trajectory program that could be used for many things, including the study of aerobrakes. But I left rather abruptly 4 years later when I saw most of areas of work being defunded. I have little hope that my program will ever be used. First because it relies on an operators thought and actions during the computation based on what he sees. Modern engineers don't like that. They set up a program and let it run itself until it hands them a solution. Curiously that was the mentality I found at NASA left over from Apollo. Secondly I used compiled Microsoft Basic which has been abandoned by Micosoft. I used it because it let me build complex elements much faster than other languages.
So it goes.
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Post by Tom Goodrick on Oct 29, 2012 6:24:03 GMT -5
Orbit speed is about 7.2 km/sec. That is at least 100 x more energy than this guy started with. Getting down to his starting energy at his starting altitude would mbe a very big job requiring a lot of deceleration using rocket fuel (a significant retro burn) or entering the atmosphere while still at or near orbit speed and then using drag to decelerate. That would generate a lot of heat that a simple suit could not handle. He would need a capsule with thrust for both attitude control and deceleration. He would need considerable thickness between himself and a special hard composite nose cone, perhaps an ablative nose cone. That gets to be a lot of weight to launch.
I have looked into that for NASA both as a worker and as a consultant and found it quite difficult. The last thing I looked at was the X-38 which was a capsule for getting the crew back from the ISS in cases of injury, illness or malfunction. The people at Houston who worked this directly could not solve the problem. They needed a big parachute. They chose a big gliding parachute so the people could have some additional control of where they land. The project was unsuccessful. Last I heard the capsule weighed just under 30,000 lbs. That's a lot of pounds to launch.
This morning a contractor landed a Space Dragon cargo capsule in the Pacific under round chutes. I heard it went well. It had 8,000 lbs of cargo from the ISS. It's a big ocean. The cargo does not care how long it rides the waves. That is the solution I advocated for the X-38 but I advocated enough on-orbit power to phase the landing, getting toward a desired spot on land with a cushioned landing.
The current Soyuz capsules have inadequate capacity.
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Post by Tom Goodrick on Oct 16, 2012 8:15:43 GMT -5
That was a significant accomplishment. He overcame the spin and made a great landing. The inflation of the parafoil canopy was a very significant thing. Hard to say what the chute deployment speed was but it was well above the normal deployment speed.
This feat does not indicate the feasibility of an entry from orbit using just a suit. The energy level that would have to be dissipated is far greater than in this jump. Speed from orbit at initial entry to the atmosphere (close to this same jump altitude) would probably be above Mach 10.
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Post by Tom Goodrick on Oct 13, 2012 6:30:05 GMT -5
From what I hear, he's still waiting. That's a tough wait. But I give him only about 30% chance of living. He'll be going pretty fast when he gets enough air to stabilize so he could easily get into a tumble. When he does get air, falling vertically, it will come as a sudden blast that can make him tumble worse. He could lose an arm.
I have advocated that people trying to get home this way ride in a small capsule with attitude-control rockets to keep them straight with some lift/drag so they can come in at an angle avoiding a big crunch.
In practical considerations, you have to wonder how a person gets to that situation anyway. Stepping out from a balloon capsule (which could be the entry capsule) is not very realistic. Anyone escaping from an orbiting device (like a space station) would have a whole new set of problems with excessive energy.
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Post by Tom Goodrick on Sept 28, 2012 13:51:36 GMT -5
If that was a joke, it was a very strange one. I don't think the guy knows what he's talking about.
I watched the whole sequence as he talking about his wife's dangerous encounter. It certainly was serious enough not to be a joking matter. She didn't act like she thought he was joking. Joe's quote above shows clearly Romney was not trying to make a joke.
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Post by Tom Goodrick on Sept 27, 2012 6:14:26 GMT -5
I trained the kid well. In a recent phone conversation, with Dr Scott L Goodrick, head of the Smoke and Flame Branch of the Southeast Research Branch of the US Forest Service, he mentioned he had been able to use some end-of-year funds to get a new tool to use in obtaining data from some "controlled [forest] burns" he does. Fortunately, he bought more than one. Here's an email he sent me this morning:
" Got to pick up my rc multi-rotor copters today !!!
Had a whole lot of fun training on how to operate (they even had a simulator program that used an rc control box for the input). We spent the day flying them around the parking lot at the hobby store that put them together for us. It is really fun flying them using the live video feed from copter (it is on a controllable gimbal that allows us to tilt the camera to look at different things). We also get data streamed back in real time that overlays the flight info on google earth. The best part is we can click a point (or a bunch of points) in google earth and tell it to go. The coordinates are sent to the copter and off it goes. When we want it back we just flip a "home" switch and the thing comes right back and lands where we launched it. Work just got a whole lot more fun."
Of course it remains to be seen what sort of problem heat and smoke present to the copters. I asked if he has a thermometer on board to warn him when it gets too hot.
During my last years at Natick Army Labs (Massachusetts) I used RC aircraft to carry small experimental parachutes to drop points and recorded dynamic descent data. That was 25 years ago. I had to use the services of an expert model flyer. Now any fool can do it.
Since his office is on the campus of the University of Georgia, this probably won't stay quiet long! Then he can learn about Politics.
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Post by Tom Goodrick on Sept 25, 2012 16:15:53 GMT -5
Today shows why it is so difficult to fly these days. I slept most of the morning. I sleep better in my easy chair in the morning than in bed at night - no complex dreams, just simple sleep. So after lunch and some Iced Coffee I decided to fly a Falcon jet. I started up FS9, set today's date and weather (beautiful). Then I started setting the fuel, passengers, etc of the Falcon 900. I found neither my keyboard nor my joystick worked. I have spent over an hour fussing with this. I have shot down and re-started the computer and reloaded FS9. I have checked the obvious - controls, etc. It is still mixed up. I am running out of time to do anything today. I have shut down FS9. I might try tomorrow.
Yesterday I spent a couple of hours getting my Songza to work. I finally did but then it had to be fixed again today. My fix for that is to fiddle with the key inputs until I get a LOGOUT tag and I log out. Then I restart and go in as a guest. That way I can legally listen to the musical playlist I organized or "created". "You cannot listen to a playlist you created. It is illegal."
Has everyone gone crazy?
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Post by Tom Goodrick on Sept 25, 2012 15:53:48 GMT -5
Yes. Any comment I would make would be construed by some as a political remark. So I won't say what a dumb nincompoop he is.
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Post by Tom Goodrick on Sept 18, 2012 18:56:14 GMT -5
Flight Aware cancels out a flight that crashes very quickly after a crash. The NTSB prelininary should be out in a few days. But it has been a busy time. We had three crashes in the last few days and then a local TV station dug out the final report on a crash from 14 months ago so they had more to talk about.
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Post by Tom Goodrick on Sept 18, 2012 18:46:51 GMT -5
Is there a difference between Real WX on FS9 and FSX?
I got it on FS9 just the other day and during the last hurricane.
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Post by Tom Goodrick on Sept 15, 2012 17:32:47 GMT -5
Yesterday I finally completed an acceptable review of the FAA Handbook mentioned above. Amazon kept bugging me for it. I guess they know something about my background. My first draft had 6367 words. A "good review" is 20 to 300 words. I had covered every topic noting what I thought was good and what I thought was not so good. I filled in more info on those topics I thought they didn't treat very well. I also said a few positive things about learning to fly and how best to go about it. Finally I realized I could not say anything about using the Flight Simulator to back up the Handbook and I had to dump all the personal opinions. there was no room for them. So after working for many days on the long version, I killed it and went through a quick summary of my original.
A few things stood out. This FAA Handbook on Flying Airplanes tells people how to take off, climb, turn, descend and land. They show photos of the common instruments. They never explain what how the instruments work. They never explain what the instruments say about the status of the airplane when shown during a flight. Once you have taken off, climbed and leveled off, they don't tell you how to go to the place where you want to land ie- how to navigate. They do tell you how to fly circles around a fixed point on the ground in a wind, how to fly S turns along a road, how to do some mild maneuvers like chandelles, figure 8's along a road and Lazy 8's. But you'd better not try to go anywhere! They discuss a number of useless things that pilots will never do after getting a ticket. They seem to be inordinately concerned that a pilot be able to fly precisely over several spots on the ground. The only time I was concerned about a spot on the ground was when I was about to land on it.
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Post by Tom Goodrick on Sept 4, 2012 16:05:11 GMT -5
Yes, that is neat. I keep forgetting to check that map when there are hurricanes.
I did make some flights in FS9 north out of Marathon when Isaac was passing near the Keys. It is always interesting to do that. As the wind got stronger, I had to move from a Baron to a King Air and then to a G IV.
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Post by Tom Goodrick on Aug 30, 2012 19:14:25 GMT -5
A friend and I took the afternoon off and watched it at my apartment. I filmed it on Super 8 so my two boys would be able to remember it. (Yes, it was in black and white. My TV only showed black and white.) The two boys were playing on the floor as we watched it. now they're grown men in their 40's. The Super 8 film ruined itself years ago. But that's okay because my Super 8 projector died first. The replays of the event we see today are much better than my films of the TV.
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Post by Tom Goodrick on Aug 15, 2012 19:05:44 GMT -5
I sure hope they don't cancel the project just because of this little problem. It really was irrelevant. The thing to be determined is if they can make all components hold together against the heat. they have been trying to get this sort of thing tested since before I retired (16 years ago). The problem has been keeping temperatures low enough so materials hold together for the control surfaces and for parts of the engines. it is the sort of thing they just have to try again and again with little improvements after each failure. First they have to determine the temperatures seen on all parts and then find ways to make the parts to withstand the heat. They are dealing with totally unknown phenomena.
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Post by Tom Goodrick on Aug 12, 2012 7:36:05 GMT -5
I still have some work to do. I have not yet visited every airport in every country in the FS2004 world. Presently, I am finding routes to Orr, Minnesota where the average high temp in summer is about 70F. Pelican Lake is a pretty place.
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