Mark I (oz9071)


Mark I (oz9071) by Courtney Smith 1964 - plan thumbnail

About this Plan

Mark One. Radio control Class I model, for .45 - .49 engines.

Quote: "The Mark I was specifically designed to take advantage of the 1963 AMA rule change allowing the use of multi-channel or proportional radio systems in Class I.

Prior to this change in rules, you will recall the rudder only model as a small craft of 300 to 400 square inches of wing area, powered by a .15 to .19 cubic inch engine, a single channel super-regen radio system linked to a compound escapement providing only limited power to move the rudder surface. All of this added up to quite a package to keep flying during the demanding contest season!

In the fall of 1962, when the current rules were still in the proposal stage, I decided to work out a basic design configuration that I would use if the new rules did materialize. Here are the features I wanted for the approaching (1963) contest season:

1. A craft strong enough to utilize the .45-.49 cubic inch engines being used so effectively by Class 3 flyers. With this size engine one can expect a dependable low idle with the power at full throttle that's so important in Class I competition.
2. A design large enough to accommodate the heavier engine and radio equipment, while at the same time maintaining the proper wing loading.
3. Good ground handling characteristics.
4. A plane with ail the above, plus the ability to perform well acrobatically and penetrate our strong midwestern winds, ever present at contests.

Our final aim was a design that would be easy to build, with a pleasing semi-scale appearance and finally to he strong and able to take the rough treatment and flying mistakes that sometimes grounds other planes.

The design was completed during November of 1962 and test flown during the winter months that followed. The Mark I exceeded all my hopes during these innumerable test flights.

The use of up-thrust in the engine has really proved to be a big help in Class I flying. With a .45 engine, the Mark I will pull into loops and other similar maneuvers without the usual spiral dive to gain the zoom speed, and yet at a fast idle the Mark I will penetrate a small gale. During the touch and go and landing maneuvers, a tap of engine speed just before touch down will bring up the nose and flare out the approach for a nice landing..."

HobbyHouse 140A or 140.1

Quote: "This is one of the few Hobby House plans that turned into an RCM Article. The Hobby House Plans Service numbering system was carried over into the RCM Plans Service. In the Plans Service advertising, it has the same 140 plan number as the MAC SEVENTEEN, published in Jan-65. So, I labeled this plan 140A or 140.1"

Supplementary file notes

Article pages, thanks to hlsat.


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Mark I (oz9071) by Courtney Smith 1964 - model pic


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