We have been working out way through the beam analysis methods of in the NASA-TM-73305. analysis manual. This latest set of spreadsheets is for combined tension and flexure of simple beams and have been authored by my talented daughter who is an engineering student at Ryerson University in Toronto. I have checked than so any remaining mistakes are […]

Many thanks to Surya Batchu for the following correction to our free textbook. At the top of Page 91 of the textbook the phrase “The interaction equation for fasteners loaded in the unthreaded shank is:” should read “The interaction equation for fasteners loaded in the thread is:”. This will be corrected in the much anticipated […]

We have corrected and updated our translational and rotational mass balance spreadsheet here. The way the additional force component due to the rotation was being calculated was not correct. We have also added a cumulative moment calculation and moment diagram. Enjoy!

An eagle-eyed engineer using our free textbook has spotted an error. We rely on the community of engineers who use our original and hosted materials to help us correct mistakes and improve the quality of our output. If you see anything that is incorrect or can be improved please comment on this post or contact us […]

We have taken a copy of the Part 23 regulations as they were on the 25th August 2017 and have reproduced them below: All of the regulations are included in the same page. You can use ‘find’ or ‘search text’ to find the information you want. To the best of our knowledge the ‘old’ part […]

Free Structures Analysis Spreadsheets Update: One of our stress engineers found an improvement to be made in the method for determining stress due to an interference fit bushing the difference between the material strengths for the lug and the bushing are now clear. We have also improved the layout and made it easier to use. Please update your […]

One of our users has found an error that under-predicts the peak stress ‘f’ in the disc washer. Revision C with the corrected expression for ‘f’ has been up loaded at the link below. Makes sure that you update your personal library with the latest version. AA-SM-042-001

We have uploaded our next set of free engineering spreadsheets. These are for three-member two-dimensional rigid frameworks. These spreadsheets are written by Sophia Abbott (my daughter) who is starting at Ryerson University in Toronto this year studying Mechanical Engineering (thankfully, she gets her talent and her looks from her mother). I have checked all of them […]

Thanks to the hard work of our esteemed technical librarian – Kenan Stewart – we have reached the milestone of 15000 unique items in our free technical library. We are building towards our aim of being the premier online aerospace technical reference library. We now average between 1500 and 2000 downloads per day from all over […]

As part of the inclusion of a Torsion chapter in the third edition of the textbook, we have revamped and broken out the torsion of regular section analyses into different spreadsheets. This also has given us the opportunity to check and make some minor corrections. Links to the spreadsheets are below.   AA-SM-002-011 Torsion – Regular […]

We are very happy to announce that the second edition of our free engineering textbook “Analysis and Design of Composite and Metallic Flight Vehicle Structures” is now available. We have also added many new free spreadsheets to our collection and now have over 200 free spreadsheets available to complement the textbook available in the Technical […]

This method is taken from our free textbook “Analysis and Design of Composite & Metallic Flight Vehicle Structures” and gives a way to calculate the shape factor in the plastic range for a ductile material. The Ramberg-Osgood Stress-Strain Curve Shape Factor in the yielding region (NACA-TN-902, 1943) can be found for most common ductile materials from  (MIL-HNDBK-5H, 1998). A more […]

This post is taken from our free textbook “Analysis and Design of Composite & Metallic Flight Vehicle Structures” and defines a method for calculating the stresses due to an interference fit bushing. The method in this section is referenced to (AFFDL-TR-69-42, 1986) Section 9.16. Note that several errors in the source material have been corrected. The […]

Recently I got pulled into some problem solving on a part 23 aircraft program. It is great to suddenly get thrown into a new group of people and try and unravel all of the technical and personal knots. These were a great bunch of engineers and it was a pleasure to spend an afternoon with them. […]

In my spare time I have been working on the next edition of the textbook. I was aware that the first edition was ‘incomplete’. In essence, every edition will be incomplete as there is always something more we can add. The First Edition was less comprehensive than I had hoped, but we had to release […]

We are happy to announce that our partner company XL-Viking has an improved website and also has a new free trial version that has enhanced functionality with no expiry. The free trial version now has the fully functioning menu with easy to use ways to add mathematic symbols and Greek letters as well as the subscript […]

We have started to catalog and upload our collection of market information to our technical library. There are many thousands of documents and this process will take some time to complete. You can get the latest list of market information documents in the section of the library at this link. Over the coming weeks and […]

I have been working on the new sections for our free engineering textbook and over the weekend I began writing the chapter for stress tensors (principal stresses, Von-Mises) and failure envelopes (Maximum principal Stress, Von Mises, Tresca). As a report writing stress engineer you seldom get the chance to stop and consider how these measures […]

After a month restricted to limited release to the members of our mailing list we are now distributing our free structures engineering textbook to the rest of the world. This book is free for you, your friends and your colleagues to use without limitation. The book links to free spreadsheet methods and all references used within […]

For the next issue of the book, (the current issue will be available to the general public for free at the end of September) we will be adding a beam analysis section. However, as with the rest of the content for the book, we want to give reference to a trusted external source for the methods we […]