This is The Major, from the Scientific Model Airplane Company. I purchased this WWII era kit at Hobbyland in Hackensack, NJ in the 1960's, when I was 12 years old. I never finished building it then, but kept the plans. I finally built it in 2020. Wingspan is 25 inches.
I have flown this indoors at the Teaneck Armory. Hit the rafters one time. A great flyer. Power is 2 loops of 1/8 rubber. The next indoor flights will use one loop of 1/8.
I flew outdoors at Barron Field in Wayanda, NY. It flew very well.