This is a question many customers have asked us over the years. Motion RC Senior Product Developer Alpha Enos explains:
"To answer the question to me regarding size, bigger birds cost more to produce and more to ship, and "Free Shipping" for our customers obviously isn't free for us. Shipping cost is a sizable consideration, as is the production cost of molding an airplane that exceeds the maximum standard mold size that many industrial molding machines are designed to handle. One could chop up a larger airplane's design into more puzzle pieces, but the overall volume would still have to be distributed across more molds, which, again, raises costs considerably. And so I must often restate that there are, unfortunately, clear reasons beyond market demand why there do not exists many foam models beyond a certain overall displacement (not just length or wingspan but total volume).
Mold frames are fixed, and maximal dimension limitations from shipping carriers are often brutal. Eflite's Carbon Z T-28 was one of my favorite Horizon planes in any material because it was such a wonderful flyer and I'm certain it was popular with most of its owners, yet it was cancelled after, what, just a couple of years? LX's beautiful 2200mm B-25 (retracts aside) cost $100+ to ship, and far more per unit to mold. Starmax's 1800mm girthy A-1 Skyraider, was about the same with ordnance. The cost/quantity just isn't there for foamies approaching true Giant Scale. For obvious reasons we can't get too deep into costs, but we've summarized in the past that it takes six figures to get a model off the ground. Imagine that. These are high hills to climb in a hobby this size, and making two or even one miscalculated big model can lead to... well... look at how many foam RC manufacturers are still growing.
Meanwhile, we've tried to push the boundaries of what we can fit in a box that still costs less than $60 to ship. That doesn't just mean making models bigger such as with our 90mm series of jets, but also in optimizing cheaper 80mm size jets to fly 90mm-sized airplanes, such that the user's overall value of size/cost increases. Getting creative with puzzle pieces has become our unintended specialty, also, with the boxes for the A-10 and F-22 being notable examples of big birds in small-but-safe boxes.
Bottom line is that there are multiple levers to balance before, during, and after an actual subject matter is selected. We do our best to balance them all for you."