John L. Loth

John L. Loth

West Virginia University

Title: CC blowing to add range with stol capability to a cessna 310


John L. Loth, received the following degrees from the University of Toronto, Canada. B.S. 1957, M.S. 1958 and PhD. 1962, with dissertation titled: Radiation From High Temperature Plasma's. From 1958-1959 he was on a Fellowship at the CNRS in France, where he designed, build and tested their 1st steady flow, magnetically stabilized plasma generator. In 1962 he was appointed Assistant Professor in the Dept. of Aerospace and Aeronautical Engineering at the University of Illinois, where he taught: Aircraft Propulsion, Supersonic and Hypersonic flow. In 1967 he joined the faculty of Aerospace Engineering at West Virginia University as an Associate Professor and was promoted to Professor in 1969, a position he held till his retirement in 2013. In addition to the above mentioned courses he taught flight testing during his 1st 15 years at WVU. In 1970 he designed the 1st CC Technology Demonstrator aircraft. This aircraft was completed in 1974, and flight tested by Shawn Roberts. This Circulation Control Technology enabled STOL flight at 33 knots, and accelerate to cruise at 160 knots. See movie of 1st flight on Google: "WVU Circulation Controlled Aircraft.avi" This new STOL technology was installed 5 years later, on a Navy A6A Crusader, at Grumman Aerospace. This also provided excellent STOL flight. After 52 years of teaching Aerospace Engineering, Loth retired in 2014. Now he does research on UAV's at the rank of Professor Emeritus and holds 18 US Patents.


Turbocharged propeller aircraft like the: Cessna 310; Beechcraft Bonanza and Cessna Cardinal, all have a wing area which is about 30% larger then is optimum for maximum range, when cruising at 20,000 ft altitude, which is the limit for turbocharged piston engines. The reason is that FAA- FAR 23,49 (a)(6), requires that all propeller driven aircraft, weighing less than 6600 lbs, must have a stall speed of no more then 62 knots (71.3 mph), in order to assure safe landing and takeoff, from airports with only a 2500 feet long runway. This FAR 23,49 does not apply to Jet Airliners. As they begin to cruise efficiently at 30,000 ft for maximum range, at CLoptimum = 0.6. As the weight of the aircraft reduces with fuel usage, it must climb, to higher altitudes, to maximize range by flying at its most efficient wing lift coefficient: CL = 0.6. Due to turbocharger limitations, propeller driven aircraft are limited in climb to a cruise altitude of 21,000 ft. Therefore, the large wing area Cessna 310, is equipped with flaps, which can be deflected to 45º, to provide CL up to 2.6, which enables take-off and landing on a 2500 ft runway. Such an excess wing area, is not fuel efficient for cruise at 20,000 ft altitude. This paper describes a solution to this problem, which is to incorporate: an in flight deployable and retractable: “Circulation Controlled, blown round trailing edge.” To provide the extra lift needed during take-off and landing, to satisfy FAA- FAR 23,49 (a)(6)”. To increase cruise speed and range, by flying with a reduced wing area