The history, early developments and achievements of soaring in the United States would not be complete without mention of Dick Johnson's RJ-5 and Leonard Niemi's Sisu 1A.
The subject of an email I received today from a modeler in Australia illustrates their importance, "Are you aware of anybody that offers a 1/4 scale plan for the Ross Johnson RJ-5? So far I have not found one, which amazes me as it was one of the outstanding American sailplane designs, together with the Sisu . It is a design I would like to build. Maybe somebody is offering models of these designs in the US, but not promoting them overseas!"
The record-setting RJ-5 hangs from the ceiling in the collection of the National Soaring Museum while directly below it, and not coincidentally, the equally important Sisu 1A which finally broke its distance record can be seen.
My response was that unfortunately and as far as I am aware, no one has drafted either ship for modelers. In fact they have likely never been built from scratch and remain two important sailplanes that have never been built in scale as flying replicas. And like Harland Ross' earlier gull wing sailplane the Zanonia, this aircraft was also a commission by a pilot that went on to win more achievements than almost any other single sailplane is U.S. or World history. Its no coincidence that its story follows that of the RS-1 in this blog.... from the http://www.wikepdia.com:
The RJ-5 sailplane has been described as one of the most famous sailplane designs, as it was one of the first to utilize a laminar flow airfoil, and the first to achieve a glide ratio of 40-to-1 (forty feet of horizontal travel for 1 foot of altitude loss). In 1948 Dick Johnson contracted with Harland Ross to design and build the glider (originally designated R-5). One key design decision was to use a NACA 63(2)-615 laminar flow airfoil selected by Dick Lyon. The NACA laminar airfoils were developed in secret during WWII, and subsequently released for public use after the war, but it its use here was unproven because no sailplane had used such an airfoil before.
However, other obligations prevented Mr. Ross from completing the project under the contracted one year schedule, so Dick Johnson took delivery of the partially completed sailplane in 1949. He completed the construction in 1950, and under the direction of Dr. August Raspet of the AeroPhysics Research Laboratory of Mississippi State University (where Dick was then obtaining a BS degree in Aeronautical Engineering) measured the glide ratio performance of the initial design at 33:1. With the help of Dr. Raspet, Dick made several modifications which in 1951 resulted in a better than 40 to 1 glide ratio - the first sailplane to achieve that milestone. At Dr. Raspet’s suggestion, the name was changed to the RJ-5. Dick Johnson flew the RJ-5 to win the US Open Class Nationals in 1950, 51, 52 and 54, to break the World Distance Record in 1951 and to break the 100 km Triangle World Speed Record in 1952. The World Distance flight of 535 miles from Odessa, Texas to Salina, Kansas was the first glider flight beyond 500 miles and exceeded the previous world record by 70 miles. This record held for 12 years, until broken by Al Parker in a Sisu glider that used a more refined laminar flow airfoil. The RJ-5 has been restored and is on display at the National Soaring Museum in Elmira, New York.
The Ross-Johnson Sailplane at Mississippi State in the 1950s.
Comments