Author Archives: mathscinotes

Gravity on Von Braun Station

Posted on 25-April-2020 by mathscinotes

I have been reading about Wernher von Braun's work with Disney on popularizing the idea of spaceflight with the public. He was a genius at marketing and a tireless champion for space flight. In addition to his television work, he also gave numerous speeches to any group that would listen. I smile as I think about my high‑school physics teacher beaming with pride when he spoke of von Braun arriving in a helicopter to speak to local physics teachers about space and flying to the moon. My physics teacher could not remember the details of what von Braun spoke about, but his entrance and exit in a helicopter made a huge impression on a town of 1800 people! Continue reading →

 
Posted in Space | 1 Comment

The Amazing de Havilland Mosquito

Posted on 18-April-2020 by mathscinotes

During the routine demolition of an old de Havilland Aircraft building in 2017, a treasure trove of 20K aperture cards (a microfilmed archive) was uncovered that contained plans for the Mosquito fighter-bomber (Figure 1). These plans have been lost since Mosquito production ended in  1950. Continue reading →

 
Posted in History Through Spreadsheets, Military History | 2 Comments

USNS Comfort Bed Count Relative To Other US Hospitals

Posted on 4-April-2020 by mathscinotes

Because of COVID-19, I am currently sheltering-in-place at my cabin in northern Minnesota. I was reading news reports of the USNS Comfort docking in New York City to provide the city with another 1000 bed hospital. I had no idea as to the average size of a hospital and decided to take a quick look at the number of beds in hospitals around the United States using a histogram. Continue reading →

 
Posted in Civics Through Spreadsheets, Excel | 3 Comments

Maple Sap is Sweet This Year

Posted on 26-March-2020 by mathscinotes

I am being a good citizen and am socially distancing at my cabin in northern Minnesota – avoiding people is easy in the dense forests that surround my residence. When I went out for my daily walk and I saw the maple sap bags that my neighbor put out (Figure 1). Most folks around here collect their sap in these blue bags. Continue reading →

 
Posted in Cabin, Personal | Leave a comment

WW2 Fighter Aircraft Fuel Fraction

Posted on 22-March-2020 by mathscinotes

I recently read a book called Boyd: The Fighter Pilot Who Changed the Art of War that documents the life of John Boyd, a fighter pilot who was critical to putting fighter aircraft design on a firm mathematical footing now called Energy-Maneuvering Theory. He was a key member of the Fighter Mafia, a group of military and industry experts in the 1970s that advocated for a lightweight fighter alternative to the large, heavy fighters like the F-111 and MiG-25. Their concepts played a significant role in the final designs of the F-16 and F-18. Continue reading →

 
Posted in Excel, History Through Spreadsheets, Military History | 2 Comments

Combined Excel Timeline/Column Chart using WW2 Naval Air Data

Posted on 10-March-2020 by mathscinotes

I recently needed to generate a graph in Excel that combined a column chart with a timeline. The graph turned out well and I decided to share my work here. As my original work is proprietary, I will share the technique here using some US Navy (USN) air operations data from WW2. Continue reading →

 
Posted in Excel, History Through Spreadsheets, Military History | Leave a comment

Web Scraping Sailboat Reviews Using Power Query

Posted on 25-February-2020 by mathscinotes

While it is true that I worked on US Navy contracts for twelve years and spent some time on ships testing new underwater vehicles, I know very little about recreational boating. However, I have always been fascinated by sailing, though this fascination has been limited to reading books about the Age of Sail. Continue reading →

 
Posted in Excel, Personal | Leave a comment

Visualizing House of Representative Data Using Power Query

Posted on 18-February-2020 by mathscinotes

I have been following certain bills through the US House of Representatives and wanted to know how the voting varied by US regions and political parties. I also want to generate tables that show how my state's representatives vote (Figure 1). Fortunately, the votes are documented online and Power Query was able to easily grab and process the data. Continue reading →

 
Posted in Civics Through Spreadsheets, Excel | Leave a comment

Power Query Regular Expression Hack

Posted on 12-February-2020 by mathscinotes

I use Python, R, and Excel every day in the course of my work. Because many corporations are focused on the Microsoft Office suite of tools, many businesses require that I use Excel/Power Query so that they can work with the tools I develop after I am done. Fortunately, I really enjoy using Power Query, but I find it irritating that it does not support regular expressions. I must admit that Power Query's standard functions can do a good job of extracting strings, but the process is a bit tedious.  However, I have a large library of regular expressions for extracting email addresses, phone numbers, social security numbers, and the like that would be efficient for me to use. Continue reading →

 
Posted in Excel | Leave a comment

US Navy WW2 Aviation Statistics Cleanup Using Power Query

Posted on 4-February-2020 by mathscinotes

was reading a forum post on fighter kill ratios during WW2 and decide to compute some  Imperial Japanese Navy (IJN) vs  US Navy (USN) ratios for myself. I should point out that these ratios are generally viewed as inflated because of the difficulty of confirming downed aircraft. However, the inflated numbers continue to be quoted. The published reports state that the F6F Hellcat had the best kill ratio of the USN/Marine fighter at 19-to-1, followed by the F4U Corsair at 11-to-1, and the F4F Wildcat at 7-to-1. Continue reading →

 
Posted in History Through Spreadsheets, Naval History | 2 Comments