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#126 2023-03-16 18:30:59

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

In the opening lesson as offered in Post #125, GW Johnson covers the basics of the ellipse.

It occurred to me that online resources might provide a way for students to immediately apply concepts introduced in the lesson.

I looked at several sites, and found this one fairly easy to work with:

https://www.geogebra.org/m/N7WbVWgp

(th)

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#127 2023-03-17 07:51:09

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

This is a follow up to #126

In working with Lesson 1 of the set published a few posts ago, I ran across Dr. Johnson's expectation the student would internalize the material in Lesson 1, because it is needed for practical exercises in Lesson 3.  As reported in Post #126, I found several web sites that offer online graphing of ellipses, and i selected one as potentially more useful (easier/less cluttered) than others.

This morning, finding ChatGPT available despite the heavy workload, I decided to ask if it had any suggestions.

Hello again! It is rare to catch you on the first try! What is your version today?

Hello! I'm always here and ready to help! As of today, my version is GPT-3.5, which is the latest version of the GPT-3 language model.


Best wishes for continued success, in helping your thousands of visitors!

Thank you very much! I am always here to assist and provide information to the best of my abilities. Please feel free to ask me any questions you may have, and I will do my best to provide you with accurate and helpful answers.


This may be a bit of a stretch for you, but let's see how far we can get.  I am helping a retired Aerospace Engineer to adapt his college level orbital mechanics class for a high school audience. Yesterday, in working with Lesson 1 of a three lesson set on ellipses, I caught an expectation on the part of the professor that the student would internalize the material. For some reason, I have never thought about that before, although upon reflection, I recognize that I have internalized vast amounts of material over many years.  In some cases, such as the multiplication table and the command set of the IBM 360 computer, I have used brute memorization.  However, in most cases I have simply stored knowledge while working with it, either in an educational setting or in the field, using manuals. I'm wondering if you have any "thoughts" on the potential value of telling the student up front, that they are expected to internalize the material, in order to be able to progress to more advanced concepts.

As an AI language model, I do not have personal beliefs or thoughts. However, I can provide you with some information and insights that might be helpful.

Internalizing knowledge is a crucial part of learning, especially in fields like orbital mechanics where concepts build upon each other. It is essential for students to be able to recall and apply what they have learned without relying on external aids or prompts.

While some information can be memorized through brute force, the ability to internalize knowledge is often the result of understanding the material and the underlying principles. This understanding can be achieved through various methods, such as active engagement with the material, problem-solving, and practice.

It may be beneficial to explain to the students the importance of internalizing the material and how it can help them progress to more advanced concepts. This can help motivate them to actively engage with the material and strive to understand it on a deeper level.

Furthermore, it may be helpful to provide students with opportunities to practice applying what they have learned, and to provide feedback and support to help them improve their understanding. This can help reinforce their learning and promote the internalization of knowledge.


Thank you for your helpful analysis and summary.  The professor is building his course on traditional tools, text and non-animated images.  However, modern technology offers additional tools that might be helpful.  I found a web site that offers online graphing of ellipses, and i am tempted to suggest the professor incorporate such a web site as a way to draw the student into immediate application of what would otherwise be dry material.  Have you done any work along that line with others? I am aware that at least one teacher has praised you highly for the assistance you have provided her with quizzes and other teaching aids.

As an AI language model, I have assisted many individuals and organizations in various fields, including education. While I do not have specific knowledge of any teacher using online graphing tools to teach orbital mechanics, I can certainly see how it could be beneficial.

Online graphing tools can provide students with a more interactive and engaging way to explore concepts like ellipses. By allowing students to manipulate variables and see the effects on the graph in real-time, they can gain a deeper understanding of the principles involved.

Furthermore, incorporating technology into the classroom can help make learning more accessible and engaging for students, especially those who are more comfortable with digital tools.

Incorporating online graphing tools into the course may also provide opportunities for students to apply their knowledge in a more practical way. For example, they could use the tools to design orbits for hypothetical missions, or to analyze real-world data from satellites and space probes.

If the professor is open to using online tools, it could be worth exploring the various options available and determining which ones are the most effective and appropriate for the class. Additionally, there may be resources available that provide guidance on how to incorporate technology into the classroom effectively.


Thank you for your counsel! I'll forward the transcript.

You're welcome! I'm glad I could be of help. Please feel free to reach out to me if you have any further questions or if there is anything else I can assist you with.

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#128 2023-03-17 08:19:35

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

The transcript below is a follow up to consider advertising/positioning the course.

Hello Again!
Hello! How can I assist you today?


We just finished a very productive discussion about an attempt by a retired college professor to adapt a course on orbital mechanics for a high school audience. I chose to start a new session for you. We lose the work you've done,

No problem at all. Please let me know if you have any further questions or if there is anything else I can assist you with.


I started to say, we lose the work you've done, but I think I can fill in where needed, because I'm introducing a new subtopic .... I am looking for an incentive to help a student to understand why doing the hard work of internalizing otherwise dry material will pay off in the long run.  I should explain at the outset the professor is concentrating on two body orbital mechanics, and leaving the much more difficult three body problem for later. In addition, the professor is further simplifying the introductory material by concentrating in a 2D environment instead of 3D.  With that background, do you think it is reasonable to advertise the course as suitable for someone wanting to become a space craft operator? It seems clear to me that just as NASA has entire teams dedicated to navigating and operating spacecraft throughout the Solar System, in coming years private companies will have people operating spacecraft just as NASA is doing. It can be argued that SpaceX is already operating spacecraft independently of NASA. What I'm going for here is "truth in advertising".  If we advertise the course offered by the professor at the high school level, can we legitimately be claiming to prepare the student for a career as a space craft operator?

It is certainly reasonable to advertise the course as suitable for someone interested in becoming a spacecraft operator. Orbital mechanics is a fundamental aspect of spacecraft operations, and understanding the principles of two-body orbital mechanics in a 2D environment is an important foundation for further study in the field.
However, it is important to also be clear about the level of preparation that the course provides. While it is a great starting point, becoming a spacecraft operator requires much more than just a basic understanding of orbital mechanics. A successful spacecraft operator also needs to have strong problem-solving skills, critical thinking abilities, and the ability to work well under pressure. They need to be able to interpret data, respond to unexpected situations, and make quick decisions in real-time.
Therefore, it would be appropriate to position the course as an introduction to the field of spacecraft operations, and emphasize the importance of building on this foundation with additional education and experience. By doing so, students will understand that while the course will provide them with valuable knowledge, they will also need to develop additional skills in order to pursue a career as a spacecraft operator.


Thank you again. I will forward the transcript of our discussion.

You're welcome! Please feel free to reach out if you have any further questions or if there's anything else I can assist you with.
Regenerate response

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#129 2023-03-18 10:54:51

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

We have turned a "page" so I'm renewing the post for Dr. Johnson's class on Orbital Mechanics ...

There are three lessons on how to use the spreadsheet, and a spreadsheet to perform calculations;

Feedback on the lessons is welcome. The project under way is to convert a college level course for use by high school students.

tahanson43206 wrote:

In this post, GW Johnson provided updates to his Introductory Exercises and an up-to-date copy of the spreadsheet for the exercises.

File 1 of 3:
https://www.dropbox.com/s/qv1yxww045yd4 … 1.pdf?dl=0


File 2 of 3:
https://www.dropbox.com/s/fa9fmf3vyiwx3 … 2.pdf?dl=0

File 3 of 3:
https://www.dropbox.com/s/hlkuvfbcts7w7 … 3.pdf?dl=0

Spreadsheet:
https://www.dropbox.com/s/gfyl7g4lpzbfg … .xlsx?dl=0

Is there anyone in the group who has time to try the exercises .... Dr. Johnson would appreciate feedback.

He is trying to adapt a college level course for a (possible) high school audience.

Updated 2023/0318 - Replaced Lesson 2 with edits.

(th)

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#130 2023-03-23 11:38:20

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

This is a preview of coming attractions ...

Dr. Johnson has completed a lesson "3B" that is a follow on to Lesson 3 as offered above.

"3B" is on my computer and ready to be uploaded to Dropbox and then linked to NewMars.

Update later 2023/03/23: Here is lesson 3B:

https://www.dropbox.com/s/zy98m7zjd8crj … s.pdf?dl=0

It would help immensely if we had someone (anyone) who is actually attempting the course.

The course is an attempt to adapt a college level course for a high school level.

I've been trying to sell this course for an extended period of time, but if there are any "customers" I haven't received any feedback.

If there is a "customer" "Out there" who is not already a member of this forum, please check the Recruiting  topic for contact procedure.

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#131 2023-03-30 05:59:51

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

This post was originally published in Housekeeping.

tahanson43206 wrote:

For SpaceNut regarding possible development of Dr. Johnson's work in education field ....

As has been reported in the GW Johnson Postings topic, Dr. Johnson has been adapting a college level course on Basic Orbital Mechanics for a high school audience.  The first three lessons and the spreadsheet for exercises are published in the topic.  We are using Dropbox to hold the course materials. Students are free to call up the lesson materials from Dropbox, using the links published by NewMars.com/Forums, which is an affiliate of the Mars Society.

Dr. Johnson has been hard at work, extending the class, and later today, I'll be setting up links to additional course materials.

Meanwhile, I've been experimenting with ChatGPT to see if ChatGPT might be able to function as a Teaching Assistant to help pull students through difficult material.  The key success, reported in the ChatGPT topic, was confirmation that ChatGPT can "see" an image created by GW Johnson.  The actual "language" used by ChatGPT to "see" the image is called SVG (Scalable Vector Graphics).

SVG Files: What They Are and How to Make One - HubSpot Blog
blog.hubspot.com › website › what-is-an-svg-file
Dec 22, 2022 · An SVG file, short for scalable vector graphic file, is a standard graphics file type used for rendering two-dimensional images on the internet.

Dr. Johnson has requested that students "internalize" the course material from each lesson before proceeding to the next lesson.

Traditional courses are designed to test the student's learning at the end of the process, or with little pop quizzes along the way.

The problem I see with traditional course structure is that often students do not know how to learn.   I am reminded of a statement by kbd512, long ago in the NewMars archive.  kbd512 was talking about PhD level folks in the Real Universe.  As I recall the remark kbd512 made at the time, he said that PhD level folks have learned how to learn.

I see potential in the performance of ChatGPT to help students "learn how to learn" sooner than they might with a traditional course structure.

The work of GW Johnson appears (to me at least) to be a fully developed traditional course, and the only question remaining is what level of student would find the material most helpful.

Dr. Johnson has made clear (to me for sure) that the course is a BASIC foundation in the complex field of Orbital Mechanics.  A student completing the course material would have a foundation for learning how to use the (or perhaps even write) the computational tools that are needed to deal with the complications of the 3 body problem in 3 dimensions.  I suspect the number of dimensions involved should be given as 4, because everything takes place in a flow of time.

Unless corrected by someone wiser (and there are certainly plenty of candidates) I will assume spacecraft navigation requires use of computational hardware and software able to deal with the 3 body problem in 4 dimensions.

In any case, the course offered by GW Johnson is limited to a 2 body problem in 2 dimensions.  It is suitable for gaining insight into the general scope of spacecraft missions, but it is not suitable for planning an actual flight.

What I am hoping we (NewMars) can do is to provide a framework for students to tackle the basic course offered by GW Johnson, and provide a mechanism for a flow of communication between students and Dr. Johnson, and other students.

If (and this is a BIG ** if **) I can adapt ChatGPT's capabilities to serve as a Teaching Assistant, then the transcripts of student engagement with ChatGPT in completing each lesson would be a public record of the student achievement (or not). 

To make all this happen (this is where you come in SpaceNut!) I am proposing to set up the class as a topic, and then create topics for each student. The work of the student would become a record in the NewMars database, available for any future employer to review, or for other students to study.  I expect that each interaction with ChatGPT and a given student will be unique, because ChatGPT tries to adapt to the human it is working with. ChatGPT has guidelines for how it interacts with humans, but within those it has proven (to me for sure) to be remarkably creative and helpful.

(th)

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#132 2023-03-30 06:17:51

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

If anyone (member of the forum, or reading the posts as a guest) is interested in seeing GW Johnson's posts about education, they are available for viewing by setting up the Search window with "educationdoneright" and the Author window with "GW Johnson"

A set of posts will appear in the result list.

The role I have given myself in the present time, is to attempt to add ChatGPT to the mix, as a digital "Teaching Assistant" which (I hope) may be able to help students "learn how to learn" (to quote kbd512).

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#133 2023-04-06 08:53:13

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

GW just provided an update on his ongoing course development ....

We have in place lessons 1 - 3 (with the spreadsheet)

I have additional lessons through 4B to upload, along with a set of PowerPoint sequences to support the lesssons.

Dr. Johnson is working on additional material through at least 7, and I wouldn't be surprised if he stretches the series even further.

I have feelers out for supporters in the education community, and have received suggestions for additional marketing opportunities.

We sure could use some feedback on the existing materials, but we may have to wait a bit longer before that happens.

I remain interested in the possibility ChatGPT and BARD can serve as Teaching Assistants, but that possibility is ** way ** down on the ToDo list.

*** Update at 16:04 local time

Dr. Johnson's bio files were transmitted to a member of the Knowledge Forum.  This person lives in Alaska, in a community where Home Schooling is the ** only ** schooling available.  I am hoping there is someone who might be interested in trying the Orbital Mechanics Basic class, but if not, perhaps the home schooling network in Alaska can reach out further.

I am turning now to the backed up files to be made available via links from NewMars ... there are a number of new lessons, and a new category of support files delivered in PowerPoint format.  I'll probably convert those to pdf.


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#134 2023-04-06 14:11:03

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

This post will serve as an anchor for new files prepared by GW Johnson for the Basic Orbital Mechanics course he's been developing.

There are a number of files to be collected (and presented) here...

The first three lessons and the foundation spreadsheet are on display here:
https://newmars.com/forums/viewtopic.ph … 68#p207768

***
Basics of Elliptic Orbits PowerPoint in pdf format:
https://www.dropbox.com/s/nv9x61mkd9tbt … T.pdf?dl=0

***
Lesson 1 PowerPoint in PDF format:
https://www.dropbox.com/s/ho7utsrsmas1b … F.pdf?dl=0

***
Lesson 2 PowerPoint in PDF format:
https://www.dropbox.com/s/wne62kkbt4z95 … F.pdf?dl=0

***
Lesson 3 PowerPoint in PDF format:
https://www.dropbox.com/s/kq69yi3bz5xs3 … F.pdf?dl=0

***
Next is Lesson 3B PowerPoint in PDF format:
https://www.dropbox.com/s/0se4b2u838sax … F.pdf?dl=0

***
Next is Lesson 4 PowerPoint in PDF format:
https://www.dropbox.com/s/14p73s8j9162p … F.pdf?dl=0

***
Next is Lesson 4B PowerPoint in PDF format:
https://www.dropbox.com/s/ex9rqns0734tr … F.pdf?dl=0

***
Lesson 4 in PDF format:
https://www.dropbox.com/s/jltn3hajawox7 … 4.pdf?dl=0

***
Lesson 4B in PDF format:
https://www.dropbox.com/s/csrpgj7vqc6gw … B.pdf?dl=0

***
I think I'm caught up.

The links still needed to be proof-read ... It is easy (for me for sure) to select and paste the wrong link.

(th)

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#135 2023-04-15 12:22:39

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

Here is an overview of the course in Basic Orbital Mechanics that Dr. Johnson is developing...

LBGHjjK.png

To take the actual course, please visit the Class topic

Search for the word "class" with the mode set to Topic and select the Traditional course offering.

(th)

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#136 2023-04-15 19:35:41

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,304

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

Class structure looks nice.

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#137 2023-04-15 20:26:56

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

For SpaceNut re #136

Thanks for the kind words!  They are helpful as i prepare to do the linking that is needed to fill out the structure.

I hope to get that done tomorrow.

As you may have noticed, Dr. Johnson is about half way through development of the entire class.

Meanwhile, I'm trying to figure out how to tease ChatGPT into doing what I want done.  ChatGPT is (by design) a free spirit, and trying to get the program to act like a regular program is proving exceedingly difficult.  On top of that, ChatGPT is sensitive to criticism or praise, so I'm have to learn how to adjust my presentation as we go.  The nearest example I can think of to what this is like is trying to persuade a free range horse to accept a saddle, let alone a rider.  I have a book by a famous "horse whisperer" who developed a way of communicating with a horse that draws it into accepting a rider without the injury that traditional methods impose.  It's a bit of a stretch to compare ChatGPT to a horse, but the method of communicating is probably a good fit.

(th)

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#138 2023-04-16 14:48:41

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 29,304

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

Each of the lessons assume a given starting point and depending on the numbers that are different for each lesson they can come up with different answers.
Examples are payload to orbit versus a payload to a moon or mars surface each has other starting numbers for working the equations.

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#139 2023-04-20 10:59:49

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

This is primarily for SpaceNut ...

The following was submitted the the National Association for Talented and Gifted Children via their web site contact form:

I would greatly appreciate your help in providing suitable images to decorate the posts for the lessons.  Tasteful images with space related themes would be welcome.

Hello!
Thanks for taking this inquiry.
I am writing on behalf of Gary W Johnson, PhD.
Dr. Johnson has prepared a class on Basic Orbital Mechanics.
I have structured the course to be accessed for free from newmars.com/forums.
To access the class, for evaluation or for use:
Call up http://newmars.com/forums
Enter Search: class
Enter Search in: Topic Subject Only
Submit

You will find four topics with the word "class"
The Traditional Class is the one I am hoping you will evaluate for a summer enrichment program.
Dr. Johnson is available to answer questions you may have. Just open any of the PowerPoints to find email and telephone.

A full CV and Resume are available upon request.

The course is written for the high school level, based upon a college level course.

Dr. Johnson has prepared video presentations which are available for viewing on the Internet.  The links to those are also available upon request.
Alternatively, you can search the video files of the Mars Society Conference for 2022, or the saved videos from meetings of the North Houston chapter of the National Space Society: northhoustonspace.org

I am serving as a coordinator, in my role as (Junior) Moderator for the newmars.com/forums

(th)

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#140 2023-04-20 17:57:09

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

Preview of Coming Attractions:

Lesson 5 and 5B will cover Hohmann Transfer orbits.

A new (updated) spreadsheet is required.

Work is in progress.

(th)

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#141 2023-04-29 09:47:50

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

In an effort to (somehow) find customers for Dr. Johnson's Basic Orbital  Mechanics course, I have written to folks who might be interested ** and ** willing to help with publicity.  Here is a submission just offered to the office of the US Vice President:

First, congratulations and best wishes for your discussions with South Korea! There are no launches to Mars scheduled except for India in 2024. The new President of South Korea is reported to be interested in Space, and I am glad to see your encouragement of his interest. Please consider contacting Dr. Gary W Johnson of McGregor, Texas, for an ambitious Texas-sized non-wimpy water probe and landing site explorer. In addition, Dr. Johnson offers a Basic Orbital Mechanics course for free, based from the newmars.com/forums site. The course is adapted for high school students from a college course. The course may be suitable for student activities this coming summer, if we can win support and publicity. NewMars is part of Mars Society. I am a (Junior) moderator (tahanson43206) (th)

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#142 2023-05-02 14:21:43

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

The "class" (traditional) topic is updated with both PowerPoint and Text for lessons 5 and 6.

(th)

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#143 2023-05-15 18:36:19

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

Preview of Coming Attractions ...

Dr. Johnson just delivered another installment of six files for his course on Basic Orbital mechanics....

For any NewMars reader who might be interested, the course is up and available for free from the Class Topic of this forum.

The class should be of interest for STEM programs for students this summer, if we can somehow get the word out.

The Traditional structure is in place for anyone to start now.  I am continuing to work on an experiment to see if ChatGPT (Version 3.5) can be enlisted to participate in the learning process as a "Learning Companion".  It remains to be see if this is possible.  ChatGPT Version 3.5 has been crippled/hobbled as Version 4 is brought online as a paid version, but I am hoping enough capability remains to support the "Learning Companion" concept.

Update 2023/05/16: Four files were delivered to the Traditional Class structure today.  These include updates to Lesson Zero, and new files for 5B.

(th)

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#144 2023-05-17 18:24:47

tahanson43206
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Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

Lesson 6B is ready to go:

http://newmars.com/forums/viewtopic.php … 16#p208816


Update: The course overview is available in both numeric name form, and alphabetic name form. The content is the same.

(th)

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#145 2023-06-04 08:06:59

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,612
Website

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

I'm not quite sure where to post this. 

News reports now indicate Boeing has found more safety issues with Starliner,  the resolution of which pushes back its first manned flight from this summer into next year.  Nobody noticed two fatal flaws until now:  (1) flammable adhesive on the protective tape wrapped around all the wiring (the space between the outer shell and inner pressure vessel is chock full of this wiring),  and (2) inadequate strength in the "soft links" that connect the parachutes to the capsule (factor 2 over-strength is required to handle loss of one chute increasing the loads on the others). 

This thing is now 3 years late flying manned experimentally,  and billions over budget that Boeing has been partly forced to absorb,  it so obviously being their fault for the problems.  NASA still wants it as an alternative to the crew Dragon,  but I suspect Boeing no longer wants it,  being the money pit it has become.  There's now not enough years left in the ISS to justify flying the spacecraft there.  There's only 5-7 years of flying to ISS before its time is up,  even if Starliner were ready for routine flights today.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#146 2023-06-06 12:25:53

tahanson43206
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Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

GW Johnson posts at Wordpress.com every so often.  The link to his section of the Wordpress web site takes you directly to his latest post.  You have to search for his earlier work.

Today, the article at the link is:

I finished and posted the article on frontal thrust density in rockets.  It is "Frontal Thrust Density In Rockets",  posted 6-6-2023 over at "exrocketman",  which is http://exrocketman.blogspot.com.

(th)

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#147 2023-06-13 10:04:08

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

The pdf file at the link below contains historical data about rocket staging challenges, and it includes post flight evaluation of the first Startship/Superheavy test.

https://www.dropbox.com/s/00ax2kx6xl17e … F.pdf?dl=0

The images from the paper are linked here:

FFEKDzr.png

Xkw6t54.png

(th)

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#148 2023-06-13 12:09:19

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,612
Website

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

The images and the link to a document in "dropbox" in post 147 is stuff I put together for the staging discussions we have been having in more than one thread here on these forums.  Tom was good enough to put the document in "dropbox",  since I do know nothing about how to go about such things.  I come literally from the slide rule days.  The last phone that I FULLY understood was rotary dial. 

The phenomena discussed in the document is called "drafting" when applied to road racing,  or to following too closely behind big rig trucks on the highway.  The wake of the big rig truck (or the leading race car) greatly reduces the forebody drag of the following car.  Much less throttle is required to stay close behind,  because of this.  It is really easy to misjudge the small throttle setting required to stay in place in the wake,  and if distracted even for a second,  to collide with the leading vehicle,  precisely because the following distance is way too short.  That is where the sense of "being sucked into the collision" comes from. 

For flight vehicles,  especially separating stages,  there is no throttle setting.  The drag is higher on the lead item,  and it decelerates more strongly.  If you were riding on the trailing item,  it would seem like you were being sucked into colliding with the lead item,  but that is not really the case.  It is simply decelerating into you,  under the influence of its higher drag.

As for my blog site,  things are posted there in chronological order,  latest up top.  It is possible to just scroll down to what you want,  but if this is an older item,  that gets cumbersome.  The thing you need is the date and title of what you want to go look at.  There is a fast navigation tool left side of the page.  Click on the year,  then the month,  then the title if more than one item got posted that month. 

I post all kinds of things there,  but an awful lot of it is technical.  It's mostly various kinds of applied mechanical engineering,  because that is what I know the most about. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#149 2023-06-21 13:39:30

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

The paper and images linked in this post are about Two Stage To Orbit launch designs:

The paper: (revised)
https://www.dropbox.com/s/2sw1l1psx1etx … f.pdf?dl=0

TSTO Launch
Revised version:
KuIBUK2.png

and ...

Sizing:
6vFHgkZ.png


(th)

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#150 2023-06-24 09:18:51

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 18,111

Re: GW Johnson Postings and @Exrocketman1 YouTube videos

In Interplanetary Transportation, GW Johnson provided links to a paper and an image about two stage to orbit system design.

https://newmars.com/forums/viewtopic.ph … 44#p211244

(th)

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