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Originally Posted by dwmzmm
Yes, I remember wondering about that when I had that catalog back in those days; to me, it
looks like a different prototype of the Centuri Space Shuttle that probably never made it to
kit status. Maybe if someone in this forum can get a hold of Leroy Piester he can provide a
definitive answer.
Wow, those WERE the good days!!
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*Flares nostrils* Ah...they were indeed! I'm going to write to him at one of his Hobby Bench shops and include a print-out of that picture to jog his memory. I have often thought of ways that one could build a Future/Fiction scale Faget-type Space Shuttle model that could dispense with the streamer-recovered motor pod used in the Centuri kit. There are two basic ways to do it:
The model could be built as a front-motor boost-glider as the Centuri kit was, but with one difference. The forward-mounted gliding orbiter would be trimmed to glide with an expended model rocket motor in its motor mount. If the orbiter fit loosely enough atop the booster using a dowel "hook" on the orbiter engaging a mounting lug on the booster (or vice-versa), the orbiter could simply slip off via drag after the motor stopped thrusting (although this would significantly limit both models' maximum altitudes and glide durations). In this version, the motor's ejection charge would be vented out of the sides or even out of the rear of the orbiter (using vents on both sides of its motor mount), and zero-delay booster motors and plugged motors could be used in this model as well.
By using either a tighter orbiter/booster fit or (preferably) a latching/unlatching pylon of the type used on pop-pod boost-gliders, the orbiter and booster would stay together and coast upward until the motor's ejection charge fired. Since the early Faget orbiter design had jet engines mounted in the forward fuselage for landing and for ferrying operations, the motor's ejection charge could be vented out through the scale nose air intake or intakes (different iterations of Faget's design had one or two nose air intakes). This would kick the orbiter backwards and free from the booster, and both would begin their gliding descents.
The other method is a bit trickier to implement. This model would look the same, but it would be configured as a rear-motor boost-glider, with the model rocket motor in the booster. In this arrangement, the booster would be trimmed to glide with an expended model rocket motor in its motor mount. The unpowered forward-mounted orbiter would serve as "nose ballast" for the booster during ascent to keep the booster/orbiter combination stable. Because the orbiter also has wings and tail surfaces (albeit considerably smaller than the booster's) and is mounted near or ahead of the combination's Center of Pressure (CP), the orbiter would have to be fairly heavy in order to move the combination's Center of Gravity (CG) far enough ahead of the CP for a stable ascent.
Also, the location of the rear-mounted motor's thrust line in relation to the booster/orbiter combination's CG point would be an important consideration. If the thrust line did not pass through (or quite close to) the CG point, it would cause the booster/orbiter combination to rotate around the CG point and pitch up or down while the motor was thrusting. The best location for the booster's motor mount would be up against the "roof" of the booster's body tube (as viewed when looking at the model from the rear). This would ensure a fairly even distribution of the orbiter's mass and the booster's mass on either "side" of the motor mount (actually, above it and below it).
In addition, the alignment of both models' wings and tail surfaces as well as their pitch trim would be important for either version, but they would be especially critical for the rear-motor version.
For the "mystery boost-glider" in the 1971 Centuri catalog, my guess is that they may have tried the rear-motor design (the orbiter in the picture isn't mounted far enough forward on the booster to work in a front-motor arrangement) and found it too tricky to be reliably built and safely flown by the average modeler.