On the 21 November 2016 the Stratos 714 took to the sky. We are proud to have played a part in this program and give our congratulations to CEO Michael Lemaire, CTO Carsten Sundin and the rest of the team. I am the structures manager for the program (with more than able assistance from the in-house Stratos engineers […]

In our office, we have been discussing how to implement effective design cost control and/or monitoring. We have had the good fortune to have worked on many different levels of projects from multi-billion dollar high-performance  jet program to much more humble part 23 prototypes. We have learned the importance of asking the following questions: Why use […]

It is risky as a business owner to make a comment that could be interpreted as political. Especially in North America where anything and everything is interpreted as political. This comment is apolitical. If you choose to interpret it as a political comment I can’t stop you. We have been using Google since we started our […]

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 […]

An old colleague of mine (Dave Robinson) recently posted an article on linked in. It was a video of an AIAA discussion panel on why aircraft take more than 4 years to bring to market. I have to admit that I did not watch the whole video. It was over 2 hours long and I have […]

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 […]

Today we uploaded a corrected version of our section property spreadsheet for common sections. This corrects some errors in the calculation of the first moment of area and the plastic bending shape factors. Revision C is the corrected version. We have also added more plastic shape factors and changed the term for First Moment of […]

In the course of developing a new a comprehensive set of section properties for common cross sections I started to look into the first moment of area of cross sections. This led me to calculating the shear stress distributions. Typically when an engineer is calculating shear stress in a cross section they calculate the average […]

Remarkable (but very frightening) video that shows tail-plane flutter.        

In the final checking stage of the creation of our Design and Analysis textbook we have changed the structure of the book. The intent of this change is to use the content we have already created in a more comprehensive content structure. This should make the book more ‘future proof’. The book is created and distributed (for […]

As part of our series of buckling analysis spreadsheet methods we have defined a quantifiable method for calculating a numerical value for panel edge rotational restraint that can be used in the standard buckling analysis methods. This method draws from a theory defined in (NACA-REPORT-735, 1942) and (NACA-TN-888, 1943). This method includes a calculation of a […]

NASA and the Smithsonian Museum have made available a high resolution 3D scan of the Apollo 11 Command module which is made up of over a trillion points. You can view it here. Screenshot of the version available on the web is shown above.  Downloadable models are available on the main page here. 47 years ago we landed on […]

Thanks to the hard work of our Technical Library staff,  our army of one: Kenan Stewart, we have just surpassed the 5000 document mark in our online Technical Library. Visit our free Technical Library site to find out more: You can help us continue and expand the library by donating here

I recently had to create a V-n diagram spreadsheet for a loads report we are working on for a client. This is for part 23 aircraft and is based on the utility category maneuver envelope, but it does show the normal category envelope for comparison. You can download the free spreadsheet here Enjoy!

We have updated the lug methods for our engineering textbook and one of the best explained and best laid out classic lug analysis comes from the US Airforce Stress Manual, AFFDL-TR-69-42  and is explained in our online textbook here. We have used this as the basis for our lug analysis spreadsheets. All of the curves are fully […]

It has been a few weeks since we posted any new analysis spreadsheets. We have been busy getting the check version of the engineering textbook ready for the mailing list subscribers which was finally released in the June newsletter. Along the way we did manage to create some analysis spreadsheets of the membrane analysis methods in […]

  This is an update to a previous post here. During further background reading I came across this reference ARC-RM-2588 which gives a more detailed method for developing spin-up loads for aircraft landing gear. When I get time I will see if it is worth adding as an alternative spreadsheet method to the library and run […]

We had to design a set of belleville washers for a client last year so we had to go and find a useful design criteria. NASA came to the rescue this time. In (NASA TM X-73305, 1975) there is a simple method for sizing and behaviour of disc springs. The behaviour of disk springs is non linear […]