Lockheed Vega (oz14578)

About this Plan

Lockheed Vega. Free flight scale model. For Cox .049 engine.

Direct submission to Outerzone.

Update 29/5/2023: Added article, thanks to RFJ.

Quote: "The Lockheed Vega presented here as a free flight scale model is adapted from one of the most popular airplanes ever built. The Vega became a major name in aviation circles, beginning in 1927, because it was the 'cleanest' and most advanced commercial airplane of its time. Horsepower for horsepower, it could outfly them all. John K Northrop and Gerry Vultee surely deserve the credit for creating this outstanding lineage of planes.

The first Vega was flown in July 1927 and christened the Golden Eagle. Ironically this plane vanished during the Dole 'Hawaiian' race of that year, but because of its unusual design and performance, many famous fliers of the day clamored for copies of it. Sir George Hubert Wilkins flew a Vega on his arctic exploring trips. More powerful versions with the 400-425 hp Wright J-5 replacing the original Whirlwind of 220 hp came into being several years later and were known as the 'Wasp' Vegas. Art Goeble and the 'Yankee Doodle' became a famous team in 1928. Frank Hawks flew an 'Air Express' version of the Vega. The most famous of all Vegas was Wiley Post's 'Round the World' flier.

It is generally believed that about 130 total Vegas were built in about 5 or 6 configurations. The last version was a 6-place transport type powered by the 450 hp Wasp engine. Since so many versions of the Vega were built as customized planes, it is difficult to arrive at any specific set of performance values, however, it can be said that some versions reputably hit over 200 mph in level flight, when equipped with all the drag reducing items, such as full NACA cowl, wheel pants, etc.

The model presented here was built from the William Wylarn series of Lockheed scale drawings which appeared in Model Airplane News in the November 1955 through February 1956 issues. Further details on a Lockheed Vega of the type presented can be found in Flying magazine for September 1965. Since the authors of this article are residents of Southern California and have seen Frank Talman's famous rebuilt Continental Airlines Vega many times, it was only natural that this would be the version copied. Hence, the Varney Speed Lanes, a predecessor of Continental. One of the authors remembers his first Vega model built in the early 1930s. Large tails, excess dihedral and rubber band-powered. It flew but only vaguely resembled the Vega. In this model, true scale proportions have been faithfully followed, including the dihedral.

Because of these requirements the model has been designed with as many breakaway features as possible, and with that all important trim requirement, a trimmable stabilizer that stays put. The authors are members of the North American Aviation 'Flight Masters' flying scale club in Inglewood, California, and have generally mastered the ability to get true to scale models to fly well.

All our ideas are not necessarily shared in by all true scale builders, but here are a few of the more important philosophies. If the real airplane was a good flyer, the model will be also, without aerodynamic changes. The model must be extremely strong, knock apart, and as a result, fairly heavy. This latter point has definite advantages as noted in meeting the following condition. The model must be capable of penetrating with no difficulty at 10 mph wind. Provide only enough power to permit a fairly medium rate of climb. No zoom power ability is permitted. The model must fly under power in about a 100 to 200 ft diameter circle with the torque, ie to the left. It should glide in 350-500 diameter circles, usually to the right. Tight turns in glides usually result in bad landings. No float in the glide, always a gentle nose down tendency.

The model must balance slightly nose heavy, usually at the 25% point so that a down load on the tail is required to maintain a steady glide. The big problem with a flying scale model is the difference between power-on and power-off trim. The weight and power loading now comes into play. A heavy model with minimum power glides fast, and if properly balanced, will use a bit of up elevator to trim out in the glide. If the CG is in the 25-30% region, the added power will provide enough nose up tendency to make the model climb and will keep the nose up in a tight turn. If the model gets into a spiral the up elevator will tend to pull the nose up as the spiral speed increases. The maneuver may look as if it is generating into a catastrophic crash, but surprisingly, it will keep the altitude position until the fuel runs out. If a scale model, with no dihedral and scale surface areas, requires down elevator for power flight as measured to the chord line of the wing, you are in trouble.

Another must for a true scale type is about 4° wing tip trailing edge up twist on the wing. This offers spiral stability and plain old stall minimization. lithe power ratio and CG are correct, you can forget all side thrust and down thrust corrections. And then the final must. A positively trimmable and fixable horizontal fin and rudder. No bend tabs, soft wire hinges, or warping surfaces. The model must be able to survive a good hard cartwheel type of landing without any changes to surface trim. If you have to bend the tails back to a guessed at position, after each landing, forget it.

The first dozen flights with a true scale model are the rough ones. It must be strong enough to survive through the adjustment period and necessarily so in one day. Do all the patching after the first day, not in between each flight on successive days. By the fifth or sixth flight, the Vega was flying like a veteran. No changes have occurred since the first day and all the damage was repaired the first night. Clay is needed to get the balance correct, and then lead is poured in to finish it up. Incidentally, there are about 4 ounces of lead in the cowl to 'balance the model as it stands. The Vega as shown can be heaved like a baseball for practice glides and will reward you with a good 50-foot distance including a good three or four foot climb..."

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