Wednesday, March 10, 2010

Issue 35


Free Flight Quarterly issue 35 was published in April of 2010.  


Issue 35 of Free Flight Quarterly  continues with the presentation of HLG and CLG glider articles  initiated in the previous issue. Tiny Gliders of 6" to 8" span are very popular in several countries and we look at designs and contest activity in USA, the UK and Brazil, both for the catapult and the hand launched varieties. Semi-scale catapult gliders, following typical 1950's early jets have also a large following and this trend is examined by a keen practitioner, David Mills. This article contains plans of the best performing designs, some of which have a very good performance and flight stability.

In an extremely interesting  related article, Paul Love  describes the use of a simple Digital camera  with Video capacity to capture  the flight of very fast catapult launched gliders. The analysis and depiction of their trajectories, during short time spans lasting less than 2 seconds is very instructive. The whole technique is thoroughly explained to enable the reader to repeat these experiments with ease. The catapult gliders  attain an initial acceleration of about 270 g's , reaching more than 100 mph ,  1/30 of a second after release.
Alternative power sources for flight: compressed air motors  are described by Chris Stoddart. This technology was once very popular, as he shows by looking at the early development of these motors.  Some designs among them  were the precursors of the rotary internal combustion engines widely used in the First WW and were made commercially in several countries. One can still build very sophisticated compressed air engine designs  with  simple hand tools.

Frank Zaic's publishing career had a very little known phase: his articles for the magazine 'Popular Science" during the decade 1935-45. Here we reprint one of his most beautiful efforts, the article he wrote in 1940 on Bower's Canadian Wakefield , second in that epic contest won by Korda the previous year.

The last installment of our envoy to the W/C in Croatia last July concerns the F1C contest, which is thoroughly reported, along with the features of the winning model by Peter Watson.

Hewitt Phillips was a very famous American aerodynamicist and enthusiastic modeller, who wrote numerous and important articles on model aerodynamics. He died last year, age 91. His career and work is remembered here by Chris Stoddart ,and we include in this FFQ issue one of his most intriguing articles: " What can be learned from Paper Airplanes". These were not the folded paper efforts out of a letter-size sheet but  9 m span gliders entirely built of paper, including circular spars, for a student design competition in the early 1960's. In spite of the limitations of the material, the gliders had a surprisingly good  performance.

Several years ago, CD Rushing  wrote  his book on the history of the Wakefield contest, an important publication  now available on-line from the FAI website. Now he has produced a plan book of the Wakefield winners, 1911 to 1956. This book is reviewed by Chris Stoddart.
Gordon Burford, the well-known Australian engine manufacturer of the Taipan and Sabre  Glow and Diesel engines also died late last year. In a short article, his  friend David Owen reminisces on his  work and personality, and Ron Chernich tells  of the legal battle  to secure the commercial names of his motors.

Sergio Montes